Apparatus for collecting, distributing and utilizing solar radiation

Page 1bibliographic recordscan →

Drawings

Page 2drawing sheetscan →

Page 3drawing sheetscan →

Page 4drawing sheetscan →

Page 5drawing sheetscan →

Page 6drawing sheetscan →

Page 7drawing sheetscan →

Page 8drawing sheetscan →

Page 9scan →

cial attractiveness and flexibility of a solar conversion

APPARATUS FOR COLLECTING, DISTRIBUTING system.

AND UTILIZING SOLAR RADIATION The rapidly-growing field of fiber optics furnishes perhaps the most promising solution to the problem of

This application is a division, of application Ser. No. developing a truly efficient solar collection and utiliza 178,784, filed Aug. 18, 1980, now U.S. Pat. No. tion system. Generally speaking, an optical fiber is a 4,411,490. long thin flexible coated rod or core of transparent

Description

material such as glass or plastic surrounded by a second transparent material or cladding. The cladding material 1. Technical Field 10 has a lower index of refraction than the core material. The present invention relates to means for collecting Light travelling down the length of the core at shallow and utilizing solar energy and more particularly to angles with respect to the longitudinal axis of the core is means for collecting solar energy at a remote location internally reflected at the core-cladding interface to and transmitting the energy so collected to a variety of effectively "trap' the light within the core material utilization devices. 15 until the light reaches the end of the optical fiber. It can 2. Background Art therefore be seen that optical fibers offer a convenient Recent interest in establishing public and private means for conducting sunlight from one point to an alternatives to the conventional use of fossil and nuclear other.

fuels for providing heat and power has focused exten The optical solar energy converter disclosed in U.S. sively on the exploitation of solar radiation as a source 20 Pat. No. 3,379,394, issued to Bialy on Apr. 23, 1968, of relatively inexpensive, renewable and non-polluting provides an early example of the use of optical fibers to energy. This interest in turn has led to new advances in receive and transmit solar radiation from a solar collec the art of collecting and utilizing solar radiation. Devel tion site to a thermoelectric unit. Additional examples opment in the field of solar cell technology, for exam of solar collectors with optical fiber networks can be ple, has made possible the realization of ever greater 25 found in U.S. Pat. No. 3,780,722, issued to Swet on Dec. efficiencies in converting sunlight directly into electric 25, 1973; U.S. Pat. No. 4,026,267, issued to Coleman on ity. Numerous improvements have also been introduced May 31, 1977; and U.S. Pat. No. 4,174,978, issued to into systems such as those employing solar heat ex Lidorenko et all on Nov. 20, 1979. In spite of the many changers and solar boilers for extracting and applying advantages to be gained from employing optical fibers the heat of solar radiation. 30 to gather and distribute solar radiation, however, the Notwithstanding the progress heretofore achieved, principal economies of size and cost available through most solar devices continue to suffer from several com the use of fiber optics are not realized in systems of the mon yet serious limitations attributable to the fact that type noted above. Specifically, all of the aforemen utilization of solar energy generally takes the form of in tioned optical fiber solar distribution systems rely upon situ utilization. The collection of solar radiation is gen 35 separate optical fibers or optical bundles to distribute erally undertaken at an outdoor location, and most solar incident sunlight from each focal point or receiving devices are designed to perform their conversion or location on a solar collecting surface. A conventional heat transfer functions at the solar collection site. Thus, solar collecting panel having a large array of solar, most solar devices are exposed to the deleterious effects receiving devices, such as illustrated in FIG. 1 of the of the elements. A particularly serious problem is cre 40 previously cited Coleman reference, consequently re ated when sensitive and fragile solar cells are subjected quires a correspondingly large number of optical fibers to such exposure. The corrosive action of the weather or fiber bundles to conduct light from the collecting significantly interferes with the operation of solar cell surface to the ultimate solar utilization device. The arrays, and the consequent maintenance and replace attendant bulk, complexity and expense of transmitting ment costs appreciably add to the overall expense of a 45 devices having large numbers of fibers or optical bun solar cell conversion system. Additional problems arise dles may, of course, prove prohibitive in many situa when solar heat exchangers or solar boilers are in tions, and it would be of obvious benefit to provide a volved. If the heat exchanger or boiler is designed to means for distributing solar radiation through a rela furnish heat to a residential unit, the solar collector is tively small number of optical fiber bundles each having often mounted on the roof of the unit and the require 50 a relatively small cross-sectional area. To this end, it is ment of close physical proximity between the collector necessary to provide a means for concentrating solar and the heat exchanger or boiler necessitates costly radiation received at a solar collection site prior to reinforcement of the structural members of the roof in transmitting the radiation to the utilization site. order to support the weight of the entire collection and Apart from systems designed to receive and distrib heat exchange system. Alternately, when the solar col 55 ute solar radiation, much recent attention has been de lector is located on the ground away from the residen voted to the development and construction of practical tial unit to be heated, complicated piping and valve devices for utilizing solar energy. Solar battery-type mechanisms are needed to transport the heat exchange arrangements which convert sunlight directly into elec medium from the collection site to heat radiators inside tricity are known, as evidenced by U.S. Pat. No. the unit. The expense of the entire collection and heat 60 4,153,475, issued to Hider et all on May 8, 1979. Al transfer system is again increased, while the process of though of obvious utility, arrangements of the type transporting the heat exchange medium and the accom disclosed in Hider et al are principally intended to func panying heat loss can lead to further costly inefficien tion through direct interaction with incident sunlight. cies. In view of these disadvantages, a means for collect No provision has been made for adapting prior art solar ing and transmitting solar energy from an optimum 65 batteries or other solar utilization devices to receive collection location to a solar utilization device posi solar radiation indirectly from optical fiber distribution tioned in a separate but optimum utilization location systems arranged to transmit light from an optimum would greatly enhance the operational efficiency, finan solar collection site to an optimum utilization site. On 10 the other hand, light utilization devices which have These and other objects of the present invention are been constructed for use with prior art optical fiber accomplished by a solar collection and utilization sys transmission systems, such as the light guide disclosed tem including a solar collection panel comprised of one in U.S. Pat. No. 4,017,150, issued to Imai on Apr. 12, or more solar gathering cells which gather and focus 1977, or the terminal lens sets disclosed in the Edmund 5 incident solar radiation through optical windows into a Scientific Co. catalog, page 59 (Spring/Summer 1979), light gathering chamber. The light gathering chamber have not been adapted to interface with solar radiation in turn employs a plurality of conical mirrors to redirect distribution systems. It is thus apparent that solar utili the solar radiation toward an optical entrance window, zation structures compatable with relatively simple, whereupon a light trap captures and removes the solar efficient and inexpensive solar collection and distribu- 10 radiation from the light collection chamber. Light trav tion systems would prove of great value in a wide vari eling through the light trap escapes via exit windows ety of both industrial and residential settings. formed at the end of the light trap opposite the entrance window and is subsequently focused by a lens system

DISCLOSURE OF THE INVENTION into a lightpipe for distribution to a remote utilization It is therefore a primary object of the present inven 15 site.

tion to provide a practical means for gathering solar One type of utilization device takes the form of a radiation at an optimum collection site and distributing light-to-electricity converter, wherein solar radiation radiation so gathered to an optimum utilization site. received from a solar collection panel positioned at a It is additional object of the present invention to 20 remote solar collection site is transmitted through a provide a means for gathering solar radiation at an light-emitting fabric overlying a plurality of solar cells. The solar cells generate usable electricity from the solar optimum collection site and concentrating the radiation radiation so gathered to enable high intensity transmission of the tricity may leaving the light-emitting fabric, which elec solar radiation through a relatively small number of be removed from the light-to-electricity converter and employed in conventional electric de optical fiber bundles to a solar utilization device located 25 vices. An alternative at an optimum utilization site. form of the light-to-electricity It is another object of the present invention to pro converter utilizes an optical tree-type structure in lieu vide a solar collection panel including at least one radia of a light-emitting fabric to distribute light received tion gathering cell for gathering solar radiation and a from the solar collection panel to solar cells mounted light collection chamber in combination with a light awithin the converter. The optical tree structure includes trunk portion with a plurality of branch portions radi trap for redirecting and removing the gathered solar ating therefrom.

radiation from the solar collection panel. Additional solar utilization devices in the form of a It is another object of the present invention to pro vide a solar collection panel wherein the panel includes asolar welder which focuses infrared radiation to furnish point source of heat suitable for welding operations, a radiation gathering cell for gathering incident solar 35 heat distributing devices for uniformly distributing in radiation and a light collection chamber in combination frared radiation as a general source of heat, and illumi with reflecting elements and a light trap for redirecting nating devices for distributing visible radiation as a and removing the solar radiation so gathered to a re source of usable illumination are also disclosed. mote utilization site with a minimum of optical loss.

It is another object of the present invention to pro- 40 BRIEF DESCRIPTION OF THE DRAWINGS vide a variety of solar utilization devices for use in The various features, objects and advantages of the connection with a solar collection panel which gathers present invention will become more apparent from the solar radiation at an optimum collection site and distrib following Brief Description of the Drawings, wherein utes the radiation so gathered to the utilization devices. FIG. 1A is a perspective view of a solar collection It is still another object of the present invention to 45 panel provide a light-to-electricity converter which receives tion; constructed in accordance with the present inven solar radiation from a remote solar collection site and FIG. 1B is a cross-sectional view illustrating the which thereafter converts the received solar radiation placement of the lens elements of a solar gathering cell into usable electricity. relative to an optical window formed in the light collec It is a further object of the present invention to pro- 50 tion chamber of the solar collection panel illustrated in vide a light-to-electricity converter which employs a FIG. 1A;

light-emitting fabric comprised of woven optical fibers FIG. 2 is an alternative embodiment of a conical to aid in converting solar radiation gathered at a remote mirror for use in the light collection chamber of the solar collection site into electricity at an optimum utili solar collection panel illustrated in FIG. 1B: zation site. 55 FIG. 3A shows a modified solar gathering cell for use It is also an object of the present invention to provide in a solar collection panel of the present invention; a solar welder for converting solar radiation into pro FIG. 3B shows another modified solar gathering cell ductive heat energy suitable for use during welding for use in a solar collection panel of the present inven operations. tion;

It is yet an additional object of the present invention 60 FIGS. 4A, 4B and 4C illustrate an embodiment of an to provide a heat distributing element capable of receiv alternative solar collection panel constructed in accor ing infrared radiation from a remote solar collection site dance with the present invention;

and distributing the infrared. FIG. 5 is a cross-sectional view of another alternative It is still another object of the present invention to embodiment of a solar collection panel constructed in provide illuminating devices for receiving visible radia- 65 accordance with the present invention; tion from a remote solar collection site and for distribut FIG. 6 is a perspective view of a light-to-electricity ing the visible radiation so received in the form of us converter constructed in accordance with the present able illumination. invention, wherein a light-emitting fabric is employed 11 to distribute light to solar cell arrays mounted within solar radiation so received onto an optical window 2 the converter; formed at the top 27 of light collection chamber 3. The FIG. 7 is a detailed perspective view of a portion of two Fresnel lenses are necessary in order to minimize an optical fiber used in weaving the light-emitting fabric the distance required to focus solar radiation on win of FIG. 6; 5 dow 2, and a small air gap preferably separates one lens FIG. 8 is a cross-sectional view of another embodi from the other. A six-sided pyramidal mirror 12 extends ment of a light-to-electricity converter constructed in from the edges of the inner Fresnel lens 11 and tapers to accordance with the the present invention, wherein an the edge of optical window 2. Pyramidal mirror 12 optical tree structure is substituted for the light-emitting serves to direct some of the sunlight improperly scat fabric of FIG. 6 as a means of distributing light to the 10 tered away from the focal point of the Fresnel lenses solar cell arrays mounted within the converter; back toward the optical window. A plastic foam 13 or FIG. 9 is a detailed cross-sectional view of a modified similar material may be used to fill and insulate the optical branch used in conjunction with the optical tree space between the top 27 of light collection chamber 3 of FIG. 8: and the lower surface of the pyramidal mirror 12. FIG. 10 is a side view of one type of heat distributing 15 Again as illustrated in FIG. 1A, light collection element for radiating infrared heat in accordance with chamber 3 extends beneath solar gathering cells 1 and the present invention; comprises a rectangular structure enclosed at the top FIG. 11 is a cross-sectional view of a heat-transfer 27, bottom 28 and three sides 29, 30, 31 by a casing housing for use in conjunction with the heat distributing having highly reflective interior surfaces. A fourth side element of FIG. 10; 20 15 of light collection chamber 3 is open to permit light FIG. 12 is a cross-sectional view of a modified heat to escape therefrom. A plurality of conical mirrors 14 distributing element and heat-transfer housing for radi are secured to the bottom 28 of light collection chamber ating infrared energy in accordance with the present 3 and are respectively positioned to receive solar radia invention; tion passing through the optical windows 2 from the FIG. 13 is a preferred embodiment for a solar heating 25 corresponding solar gathering cells 1. Conical mirrors furnace wherein the heat distributing elements of FIG. 14, which in the preferred embodiment are formed with 11 are employed to supply heat for the operation of the a 90° apex angle, have the effect of scattering incident furnace; solar radiation in a direction parallel to the top and FIG. 14 is a cross-sectional view of a solar welder for bottom planes of the light collection chamber. The solar converting infrared radiation into a point source of heat 30 radiation scattered from the conical mirrors is subse for use during welding operations; quently reflected back and forth between the interior FIG. 15 illustrates one embodiment of a lighting fix surfaces of sides 29, 30, 31 until escaping from light ture constructed to receive light from a remote solar collection chamber 3 at open side 15. Some light passing collection site in accordance with the present invention; through any given optical window 2 will initially scat FIG. 16 is a second embodiment of a lighting fixture 35 ter off the conical mirror associated therewith only to constructed in accordance with the present invention be re-reflected from another conical mirror toward the wherein the lighting fixture is portable; and top surface 27 of the light collection chamber. In such a FIG. 17 is a cross-sectional view of a recessed light case the light may escape through an optical window 2 ing fixture constructed in accordance with the present or simply reflect back and forth between the top 27 and invention for mounting in the ceiling panel of a home, 40 bottom 28 surfaces of light collection chamber 3. In this store, office or other building. event optical loss will occur, but such loss can be mini

Best mode for carrying out the

mized through careful choice of the dimensions in

Invention

volved in constructing the solar collection panel com ponents.

The preferred embodiment for a solar collection 45 Light escaping from light collection chamber 3 panel of the present invention will now be described in through open side 15 enters a rectangular optical en detail with reference to FIGS. 1A and 1B. The solar trance window 16 formed at one end of light trap 4. As collection panel is indicated generally at 24 in FIG. 1A. previously discussed, light trap 4 is designed to remove Solar collection panel 24 includes an array of solar light from the light collection chamber. To this end, gathering cells 1 which gather incident sunlight, a light 50 light trap 4 is fabricated from a single piece of optical collection chamber 3 which coherently redirects light grade plastic which is capable of channeling light from gathered by solar gathering cells 1, a light trap 4 which rectangular entrance window 16 to a series of progres removes the redirected light from light collection sively elongated light guides 17 formed at the end of chamber 3, a lens system 26 which focuses and intensi light trap 4 opposite rectangular entrance window 16. fies the removed light, and a light pipe 8 which distrib 55 Each light guide 17 has an exit window 18 through utes the intensified solar radiation to various solar utili which light can escape. The cross-sectional areas of the zation devices. For purposes of illustration, only four exit windows 18 vary in proportion to the progressive teen solar gathering cells 1 arranged in a hexagonal lengths of the corresponding light guides 17 and all of pattern across the surface of solar collection panel 24 the light guides 17 may be bent, curved and stacked as are disclosed in FIG. 1A. In practice, however, each 60 illustrated in FIG. 1A such that exit windows 18 verti solar collection panel of the present invention may con cally align to face lens system 26. Apart from rectangu tain hundreds of solar gathering cells arranged in any lar entrance window 16 and exit windows 18, all of the suitable pattern, and an actual solar collection device interior surfaces of the light trap are optically coated or may employ several such solar collection panels. processed to render the light trap highly reflective to Turning to FIG. 1B, it can be seen that each solar 65 internal light. Thus, a substantial portion of the light gathering cell 1 consists of two Fresnel lens 10, 11 escaping through the open side 15 of light collection which receive solar radiation impinging upon the upper chamber 3 is directed through light trap 4 to exit win surface of panel 24 and focus substantially all of the dows 18. If desired, the overall bulk of light trap 4 can 12 be reduced by tapering the sides of the light trap as switches can be positioned at appropriate locations indicated at 19 and 20. along the lightpipe network. Moreover, because large Light leaving the exit windows 18 in light guides 17 solar collection panel matrixes may send thousands of passes through lens system 26 where a first series of watts of electromagnetic energy through a lightpipe lenses 5 reduces the angular divergence of the light to 5 network, it may also be necessary to install safety shut form a coherent beam. A second series of lenses 7 re off switches at additional points within the various light ceives the coherent beam from lens series 5 and further channels and lightpipe trunk line. reduces the angular divergence of the light contained Numerous modifications to the solar collection panel therein to focus the beam through an optical coupler 9 of the present invention may be made for the purpose of and on into the end of lightpipe 8. Lightpipe 8, which O increasing the efficiency and/or reducing the costs of comprises a bundle of optical fibers bound together and the solar collection process. For example, the solar surrounded by one or more protective coatings of gen gathering cells 1 illustrated in FIGS. 1A and 1B include erally opaque material, in turn serves to distribute light two Fresnel lens 10, 11 and a pyrmidal mirror 12, but from solar collection panel 24 to various remote solar other combinations of lenses and mirrors can be equally utilization sites. Both ends of the lightpipe are cut and 15 effective. Simplified versions of the solar gathering cell polished to form flat, optically transmissive surfaces. may be constructed using only one Fresnel lens. In Where the flow of light along the lightpipe is generally many applications, the pyrimidal mirrors 12 could be unidirectional, the flat optical surfaces may be referred entirely eliminated without substantial loss of light gath to as optical input and output windows in accordance ering efficiency. On the other hand, a more complex with the direction of light flow. An optical coupler such 20 version of a solar gathering cell using three or more as optical coupler 9 is secured to each flat optical sur Fresnel lenses could be fabricated to gather light ap face and serves to conduct light into or out of the ligh proaching the solar collection panel at non-vertical tpipe depending upon whether the flat optical surface is angles. The Fresnel lenses may be replaced by other functioning as an input or output window. Although focusing elements such as conventional lenses or grated hundreds or even thousands of optical fibers can be 25 parabolic refractive indexed rod lenses to provide lens bound together in the lightpipe, the bundled fibers and systems capable of narrowing the angular dispersion of associated coatings are arranged such that the resulting the collected sunlight focused through optical windows lightpipe exhibits some degree of flexibility. Lightpipes 2. Any of the lenses employed in the various lens sys can vary from one-eighth of an inch to over an inch in tems could be fabricated from transparent glass, plastic diameter. 30 or other suitable optical material and all lenses lying in If desired, a light channel 6 for carrying light from the same plane in a solar collection panel can be molded adjacent solar collection panels (not shown) may be in a single sheet. Baffles would then be placed between positioned atop the stacked light guides 17. Light leav the various solar gathering cells to prevent light col ing the transparent face 22 of light channel 6 is com lected by one cell from crossing over into the lens sys bined in lens system 26 with the light leaving exit win 35 tem of an adjacent cell. The baffles could contain highly dows 18 and is likewise focused into optical coupler 9 reflective surfaces to form in essence, vertically stand and lightpipe 8. Light channel 6 is fabricated from a ing mirrors between each layer of lenses. These mirrors solid piece of optical quality plastic and, in a manner would also serve as structural supports for keeping the analogous to light trap 4, contains surfaces highly re layers of lenses spaced at an optimum distance from one flective to interior light. A rear optical window 21 can 40 another. The various solar gathering cells could addi be formed in light channel 6 to serve as a focal point for tionally be arranged along more than one light gather light beamed from the exit windows in the light trap of ing surface in a solar collection panel, or the panel could an adjacent solar collection panel (not shown) through be shaped to form a curved light gathering surface. an additional series of lenses (not shown) similar to lens A further variation in the construction of the solar series 5. Optical window 21, if employed, has a greater 45 collection panel of the present invention can employ a cross-sectional area than the cross-sectional area of means such as a multiple layer interference film to split optical window 22. light collected by the panel into physical and infrared The output of the solar collection panel 24 illustrated components. U.S. Pat. No. 3,314,331, for example, is in FIG. 1 is focused into a single optical coupler 9 and sued to Wiley on Apr. 18, 1967 and incorporated herein lightpipe 8. In practice, however, a plurality of solar 50 by reference, discloses an interference film suitable for collection panels are usually mounted in a large rectan this purpose. The interference film is mounted within gular matrix arrangement on the roof of a building or light trap 4 and the electromagnetic components de other solar collection site, and the simple optical cou rived therefrom are separately directed through indi pler associated with the last panel in each matrix row of vidual light guides and optical networks, each of which solar collection panels is replaced with an optical merge 55 is similar to the light channel 6, lens system 26 and device. A lightpipe trunk line of much greater cross lightpipe 8 illustrated in FIG. 1. The optical network Sectional area than lightpipe 8 can then be strung along carrying visible radiation can supply light for interior the edge of the solar collection panel matrix between illumination in a residence or commercial building, the optical merge devices. Light transmitted through while the infrared optical network may be used to fur the light channels associated with each matrix row, 60 nish radiant heat for a heating or hot water unit in the such as light channel 6, is then combined in the lightpipe building.

trunk line via the optical merge devices with light re A more efficient means for forming a light collection ceived from the light channels of other matrix rows to chamber for use with the present invention may be seen form a single high intensity beam in the lightpipe trunk in FIG. 2. Each of the conical mirrors 14 secured to the line. Thereafter, the lightpipe trunk line distributes the 65 bottom of light collection chamber 3, having 90° apex high intensity beam to solar utilization sites. In order to angles as illustrated in FIGS. 1A and 1B, is replaced by permit maintenance or installation work at various a conical mirror 32 having non-linear reflective surfaces points in the light distribution network, optical "on-off formed in the shape of parabolas when viewed in cross 13 section. The parabolas, such as 33 and 34, have a center collection panel to a utilization device. As is the case of focus F1 located at the center of the corresponding with the FIG. 3A embodiment, scattering of light optical window 35. A lens element 36 positioned above within the solar collection panel is eliminated and the optical window 35 is placed at a predetermined distance radiation gathering efficiency of the panel is corre from the optical window such that any light rays im- 5 spondingly enhanced.

pinging on lens element 36 are focused through point Where the simultaneous gathering of infrared, visible F1 and reflect from the parabolic sides of conical mirror and ultraviolet radiation is desired, solar collection pan 32 in accordance with well-known geometrical formu els 46 as illustrated in FIGS. 4A, 4B and 4C can be las to continue along a perfectly horizontal path relative designed to use curved mirrors rather than lenses for to the floor of the light collection chamber. Thus, light 10 gathering the radiation. Incoming radiation waves R1 losses due to reflection between the floor and the top of and R3 first strike a parabolic mirror 48 and are re the light collection chamber are minimized, and the flected to a section of a spherical mirror 50 which fo light rays reaching the light trap at the edge of the light cuses the radiation waves through an optical window 52 collection chamber are collimated to a greater degree formed in the center of parabolic mirror 48. A conical than would otherwise be the case. 15 mirror 54 caps the spherical mirror 50 to enable the The preferred embodiment of the solar collection gathering of radiation waves such as Rs which would panel illustrated in FIG. 1A combines a high light gath otherwise be lost. Radiation passing through optical ering efficiency with relative ease of fabrication. A window 52 enters a collection chamber 56 similar to the more complex arrangement of components can never light collection chamber 3 of FIG. 1A and is reflected theless be employed to achieve a theoretical light gath- 20 from a conical mirror 58 similar to conical mirror 14 in ering efficiency approaching 100% for light incident at FIG. 1A. Conical mirror 58 acts to direct radiation from right angles to the panel surface. Turning to FIG. 3A, a collection chamber 56 into a radiation trap 60 which solar gathering cell 37 utilizing a plurality of lenses 38 extends from one end 62 of solar collection panel 46 and collects solar radiation over a wide angular range and then curves underneath the solar collection panel to focuses the radiation so collected into a narrow vertical 25 conduct radiation therefrom. As with light trap 4 in beam B1 with a minimum of angular dispersion. The FIG. 1A, radiation trap 60 may be fabricated from a narrow beam is passed through an optical window 39 single piece of optical grade plastic having an external and into a light collection chamber 40 which is uniquely coating of optically reflective material such that radia associated with solar gathering cell 37 and has a small tion traveling through radiation trap 60 from collection cross-sectional area relative to the cross-sectional area 30 chamber 56 undergoes total internal reflection. The of light collection chamber 3 in FIG. 1A. Curved, mir internally reflected radiation escapes from the trap rored surfaces 41 on either side of optical window 39 through an exit window 64 at the end of solar collection may be employed to redirect radiation inadvertently panel 46 opposite end 62.

falling outside of beam B1 back through optical window As seen to best advantage in the plan view of FIG. 39. A 45 mirror 43 is positioned below optical window 35 4B, exit window 64 is parallel to the longitudinal axis of 39 at the end of light chamber 40. Beam B1, together radiation trap 60. A mirrored surface 66 formed along with any incidental radiation redirected through optical the end of radiation trap 60 at a 45° angle relative to exit window 39 by curved, mirrored surfaces 41, impinges window 64 serves to redirect radiation waves from the on 45' mirror 43 and is reflected in a horizontal direc interior of radiation trap 60 through exit window 64. tion without scattering. Light collection chamber 40 40 For example, a radiation wave R7 traveling in a direc serves as a light guide for conducting the horizontally tion parallel to the longitudinal axis of radiation trap 60 traveling radiation away from the solar gathering cell is reflected by mirrored surface 66 and escapes radiation 37, and all of the interior surfaces of light collection trap 60 via exit window 64 in a direction generally chamber 40 are coated with a highly reflective material. perpendicular to the plane of the exit window. Refer As previously indicated, a light collection chamber is 45 ring to FIG. 4C, the tip of radiation trap 60 containing individually associated with each solar gathering cell exit window 64 and mirrored surface 66 may be rolled 37. Consequently, a single solar collection panel con about a lightpipe 68 as indicated by arrow 70 in order to structed using the solar gathering cells of FIG. 3A reduce the overall space necessary to accommodate the would contain a large number of light collection cham exit window. Lightpipe 68 functions to conduct radia bers such as light collection chamber 40. The individual 50 tion from an adjacent solar collection panel (not shown) light collection chambers meet at the edge of the solar in the direction of arrow 72. Radiation traveling parallel collection panel, where they are all arranged to direct to the longitudinal axis of radiation trap 60, as indicated light toward a lens system such as lens system 26 in by arrows 74, is reflected through exit window 64 by FIG. 1A. It can be seen that the use of lenses 38 and 45 mirrored surface 66 and generally exits trap 60 in the mirrors 43 in conjunction with individual light collec- 55 direction indicated by arrows 76. If desired, a lens sys tion chambers 40 substantially eliminates the scattering tem (not shown) may be used to merge the radiation of solar radiation within the solar collection panel, and leaving exit window 64 with the radiation traveling hence essentially all of the light entering the panel may through lightpipe 68 in a manner analogous to the merg be gathered and made available for subsequent distribu ing of light from exit windows 18 and light channel 6 by tion to solar utilization devices. 60 lens system 26 in FIG. 1A.

FIG. 3B illustrates a modification of the solar gather FIG. 5 illustrates another type of solar collection ing cell of FIG. 3A, wherein like elements are desig panel 78 constructed without lens elements. Radiation is nated by like reference numerals. 45 mirror 43 and admitted to a collection chamber 80, the interior walls light collection chamber 40 of FIG. 3A are replaced by 82 of which are coated with a mirror-type substance, an individual optical fiber 44 which is coupled directly 65 via a simple sheet of optical glass 84 having a relatively to the optical window 39. The various optical fibers low index of refraction. Collection chamber 80 is filled from each solar gathering cell are then merged to form with a transparent optical grade material 86 having a a lightpipe for directing solar radiation from the solar relatively high index of refraction, and a series of coni 14 cal mirrors 88 are suspended within the optical material 3,912,392, issued to Hudson on Oct. 14, 1975 and incor 86. All external surfaces of the mirrors 88 are highly porated herein by reference. Various groupings of opti reflective. In addition, a series of conical mirrors 90 cal fibers are segregated from one another for the pur with highly reflective exterior surfaces are positioned at pose of transmitting light to respective LEC compart various intervals along the floor of collection chamber 5 ments. The individual optical fibers 126 of each group 80. A tapered portion including an inclined, mirrored ing are thereafter arranged within corresponding LEC surface 92 is constructed at one end of the collection compartments to form the warp of a piece of light emit chamber, and terminates in a spiral shaped mirror 94 ting fabric 128, as disclosed in co-pending application having a highly reflective interior surface 96. Mirror 94 Ser. No. 007,592 filed Jan. 29, 1979, now U.S. Pat. No. encloses a cavity 98 which acts as a radiation trap for 10 4,234,907 to the inventor of the present invention. The conducting radiation away from collection chamber 80 woof of light emitting fabric 128 may be formed from and which may also be filled with a transparent, highly optically inert fibers 130 if desired, but in any event refractive optical grade material. One end of cavity 98 fabric 128 is designed to radiate light at a uniform inten may be capped with a flat mirror (not shown) lying in a sity across the entire fabric surface. Two solar cell ar plane parallel to the plane of FIG. 5. The other end of 15 rays 132, 134 respectively positioned above and below cavity 98 is left uncovered to serve as an exit window light emitting fabric 128 function to convert light radi for the radiation conducted therethrough. A radiation ated from the fabric into electricity. Each solar cell wave such as R9 traveling toward solar collection panel array may be comprised of one or more conventional 78 passes through optical glass 84 and is reflected back solar cell elements which generate electrical current in and forth between conical mirrors 88 and 90 and the 20 response to incident solar radiation. Alternatively, solar reflective surface 96 of spiral shaped mirror 94 until cell arrays 132, 134 may utilize various combinations of leaving cavity 98 through the aforementioned exit win photogalvanic cells, such as those disclosed in U.S. Pat. dow. Due to the simplistic construction of solar collec No. 4,080,488 issued to Chen et all on Mar. 21, 1978 or tion panel 78 it should be noted that an occasional radia U.S. Pat. No. 4,138,532 issued to Chen on Feb. 6, 1979, tion wave such as R will enter collection chamber 80 25 to store as well as generate electrical energy. The cur only to be reflected back toward optical glass 84 at an rent from each solar cell array is collected at a terminal angle greater than the critical angle of the glass. Al lug 136 and is conducted along an electrical lead 138 to though radiation wave R11 will thus be lost for useful a female electrical connector 140. The total electrical purposes, if proper care is exercised in formulating the output from all of the LEC compartments is removed dimensions of solar collection panel 78 this type of loss 30 from the LEC via a male connector 142. can be minimized. If desired, two sheets of photochemical glass 144, 146 As previously discussed, incident radiation gathered may be respectively inserted between light emitting and focused by any of the solar collection panels illus fabric 128 and photocell arrays 132, 134. Photochemical trated in FIGS. 1 through 5 may be conducted through glass sheets 144, 146 are highly transparent to low or light pipes such as light pipe 12 illustrated in FIG. 1 to 35 medium intensity light but darken slightly in the pres a solar utilization device positioned in an optimum utili ence of high intensity light. Thus, the sheets act to pre zation site. One such device, in the form of a light-to vent excessive light intensities from damaging the LEC electricity converter 100 (hereinafter referred to as an solar cell arrays. The solar cell arrays can in turn be LEC) is shown in FIG. 6. LEC 100 includes end covers operated at maximum efficiency for a far greater pre 102,104 fastened to top and bottom portions 106, 108 by centage of time, inasmuch as the LEC components can bolts 110. End covers 102 and 104 may be constructed be designed to provide total saturation of the individual from sheet metal or other suitably durable material, solar cells at a light intensity less than the peak intensity while top and bottom portions 106, 108 may comprise of light received from the solar collection panels when thick aluminum extrusions. A plurality of parallel sup the sun is shining brightest. On those days when the sun porting plates 112 integrally fabricated from yet another 45 does produce maximum light intensity, excess radiation aluminum extrusion are placed in sandwich fashion reaching the LEC will be harmlessly dissipated by the between the top and bottom portions 106, 108 to form a photochemical glass sheets 144, 146. series of compartments in the interior of the LEC. For FIG. 7 illustrates in detail the individual optical fibers the sake of clarity, only the uppermost compartment is 126 which together constitute the warp for the various depicted in the cut-away view of FIG. 6. The support 50 pieces of light emitting fabric 128. Optical fibers 126 ing plates 112, which may be secured in position by include a core material 148 surrounded by cladding 150. bolts 114 inserted through appropriate holes (not During manufacture the optical fibers are mechanically shown) bored in a lip 116 on top portion 106, terminate, or chemically deformed by etching, sandblasting, heat on both sides of the LEC in a series of cooling fins 118. treating or the like to create pits or apertures 152 which The cooling fins complete the enclosure of the LEC, 55 penetrate cladding 150 to expose the core material 148. and additionally provide a means to disipate heat gener The resulting irregularities in the core material disrupt ated in the LEC during the light-to-electricity conver the uniform internal reflecting properties of optical sion process. fiber 126 and permit some of the light traveling along Light gathered at a solar collection panel (not shown the fiber to escape through the apertures 152 into the in FIG. 6) is conducted to LEC 100 by a lightpipe 120 surrounding environment. The deformation operation is and passes through end cover 102 to the interior of the controlled such that more apertures per unit length LEC via an optical coupler assembly comprising male occur on the portion of the optical fibers 126 lying coupler 122 and female coupler 124. Light emerging furthest from the source of light. Consequently, the net from the female coupler 124 is next uniformily dispersed intensity of light leaking from or emitted by the optical into a plurality of optical fibers 126 attached to the inner 65 fibers 126 can be kept at a uniform value over the entire end of the female coupler. For this purpose, female fiber length, and the light emitting fabric 128 subse coupler 124 may take the form of a fiber optic bundle quently formed from optical fibers 126 will provide terminator such as that disclosed in U.S. Pat. No. even illumination across the entire fabric surface. "Hot 15 spots" which may be present due to unusually large ally at 154, is illustrated in cross-section in FIGS. 8 and apertures 152 created during the deformation operation 9. LEC 154 includes a housing 156 which surrounds and may be minimized by adjusting the thickness of photo protects the optical and conversion components of the chemical glass sheets 144 and 146 to diffuse any exces LEC. The inner surfaces of housing 156 together with a sive amount of light over larger areas of the solar cell 5 series of support arms 158 projecting inwardly from the arrays 132, 134 positioned on either side of the light sides of the LEC serve to divide the interior of the LEC emitting fabric. into various compartments 160. In lieu of the light emit The optically inert fibers 130 which constitute the ting fabric 128 of FIG. 6, an optical tree 162 is employed woof of light emitting fabric 128 may be fabricated from to distribute light to a plurality of solar cell arrays 164 either transparent or reflective material, but the use of 10 mounted within compartments 160. Optical tree 162 is any type of light absorbing fibers should be avoided in fabricated from a single piece of optical grade plastic order to prevent loss of any light radiated from the formed by injection mold casting, and includes a trunk optical fibers 126. In the preferred embodiment of the portion 166 with a plurality of optical branches 168 present invention, inert fibers 130 are thin metallic wires radiating therefrom. Each optical branch 168 may ex such as chrome plated copper wires which both reflect 15 tend around the entire circumference of the trunk por light and conduct heat from the interior of the LEC to tion 168 in true three dimensional fashion. Alternately, cooling fins 118. Although not specifically illustrated in two sets of branches can radiate from opposite sides of FIG. 6, the ends of the metallic fibers may be attached trunk portion 166 as indicated in FIG. 8 and two addi to the interior surfaces of the cooling fins to assist in the tional sets of branches can radiate along planes horizon heating conducting process. If desired, additional metal- 20 tally perpendicular to the plane of FIG. 8 on either side lic fibers (not shown) may be woven in parallel with of the Figure. The surfaces 170 of optical tree 162 repre optical fibers 126 to further reflect light toward solar sented in FIG. 8 by solid lines are covered with a highly cell arrays 132, 134, and to further conduct heat from reflective mirror coating, while the optical tree surfaces the interior of the LEC. 172 represented by dashed lines are at least partially Numerous modifications of the LEC illustrated in 25 transparent. Light from lightpipe 174 enters the LEC FIG. 6 are possible. For example, an optical mixer ele 154 via optical coupling means 176 and passes into opti ment may be included as part of female coupler 124 to cal tree 162 through an optical window 178 formed at enhance the uniform distribution of light among optical one end of trunk portion 166. Curved sections 180 link fibers 126. Alternatively, the single female coupler 124 ing the optical branches 168 to trunk portion 166 are may be replaced by several couplers arranged at differ- 30 covered with the aforementioned mirror coating in a ent locations on the LEC end cover 102, or female manner such that each optical branch captures some of coupler 124 may be eliminated entirely in favor of a the light received through optical window 178. Light light pipe assembly which runs directly into individual captured by the branches 168 in turn escapes through LEC compartments. Light emitting fabric 128 may be transparent surfaces 172 and impinges upon the solar treated with various coatings having specific optical 35 cell arrays 164 to produce electrical current, Mirrored properties in order to produce more desirable distribu ends 182 of optical branches 168 reflect light reaching tions of light within the LEC compartments, and the the end of the optical branches back toward the trans light emitting fabric may be fused or laminated between parent surfaces 172. If desired, the intensity of light the two sheets of photochemical glass 144 and 146. The escaping through surfaces 172 can be made uniform by photochemical glass sheets themselves may be replaced 40 covering the areas of surfaces 172 nearest the trunk by ordinary glass or other transparent materials such as portion 166 with an optical material having partially soft plastic or glass fiber mats. Sheets formed from soft reflective and partially refractive properties while leav plastic or glass fiber mats will of course compress some ing areas of surfaces 172 furthest from trunk portion 166 what when the LEC is bolted together, thereby forcing completely transparent (i.e., completely refractive). the solar cell arrays 132, 134 into a snug fit against the 45 Photochemical glass sheets 184 may be inserted be top and bottom surfaces of the various LEC compart tween the various optical branches 168 and solar cell ments. If desired, one of the solar cell arrays in each arrays 164 to protect the arrays from damage due to compartment can be removed to simplify the LEC excessive light intensities. Cooling fins 186 formed construction. When only one array of solar cells re around the outside of the LEC 154 assist in dissipating mains per compartment, the light emitting fabric associ- 50 heat generated during the light-to-electricity conver ated therewith will be manufactured such that light sion process.

only radiates from the fabric surface facing the array The enlarged cross-sectional view of FIG. 9 illus while the fabric surface opposite the array will be cov trates one optical branch 168' of an optical tree wherein ered with a reflective mirror to direct light back toward a more complex arrangement of optical elements is the array. 55 employed to distribute light more evenly across the The end covers 102, 104 of the LEC can be enlarged faces of a solar cell array. As in FIG. 8 the solar cell to include electrical components such as storage batter arrays 164 and the photochemical glass sheets 184 are ies in accordance with the particular circumstances of positioned within a compartment formed by supporting LEC utilization. A suitably minaturized LEC could be arms 158 to receive light from the optical branch 168". mounted on a portable appliance and employed with a 60 In the FIG. 9 embodiment of the present invention, flexible lightpipe in a manner analogous to a conven however, optical branch 168' is tapered rather than tional electrical extension cord hookup. When the LEC rectangular in shape, curving toward an apex 188 at the is secured in a stationary mode, heat radiating from the far end of the LEC compartment 160. Transparent areas cooling fins can provide a source of heat energy. Air or 190 on the outer surface of the optical branch are again water can then be circulated around the LEC to effect 65 indicated by a dashed line and mirror coated outer sur a heat transfer function. faces 192 of the optical branch are represented by solid A second embodiment of an LEC constructed in lines. Two optical glass or plastic elements 194, 196, accordance with the present invention, indicated gener each containing a plurality of grooves 198, are respec 16 tively fitted to the top and bottom of optical branch 168 panels such as might be fabricated from flexible trans between the optical branch and photochemical glass parent plastic material or the like, would be designed to sheets 184. Grooves 198 are cut at an angle such that float in water with the light gathering surfaces of the light entering either element 194 or 196 always emerges panel facing skyward. The inherent flexibility of the from one of the vertical faces of the grooves to strike 5 plastic would enable the entire panel array to bend with optical glass elements 184 and solar cell arrays 164. A ease, thus preventing structural distortion or other dam mirrored surface 200 may be positioned at the terminus age by allowing the entire panel array to conform to the of compartment 160. A light ray such as R13 entering motion of the waves. Collected sunlight would be chan optical branch 168' is reflected between the mirrored neled into optical fiber lightpipes and conducted to surfaces 192 at the top and bottom of the optical branch O LEC arrays or other devices for conversion into elec until the transparent area 190 on the surface of the opti tricity, heat or usable light. The solar devices may be cal branch is reached. As FIG. 9 indicates, the curva mounted at fixed locations on either the seashore or ture or taper of optical branch 168 causes light ray R13 seabottom or they may be carried by divers with suit to strike surface 190 at progressively greater angles 61, ably constructed lightpipe delivery systems. Alterna 62, 63 and 64. Consequently, for any given light ray 5 tively, large solar collection panel arrays could be there is a lesser chance that the shallower angles of towed behind a ship to provide some or all of the light, incidence 61 and 62 will be greater than the critical heat and electric power required by the ship. angle (i.e., the maximum angle at which internal reflec Flexible solar collection panel arrays will, of course, tion occurs) of the optical branch. On the other hand, be as usable on land as at sea. When not collecting solar where steeper angles of incidence 63 and 64 occur, the 20 radiation, such arrays can be rolled up for convenient likelihood that the critical angle will be exceeded in transportation and storage. Accordingly, flexible solar creases. When combined with the fact that light along collection panels in combination with suitable LEC an optical conduit such as optical branch 168 generally arrangements would prove of great benefit in providing decreases in intensity as a function of distance, the effec electrical power at campsites, construction sites, or tively increasing angle of incidence and correspond 25 military field sites. Flexible panels could also be em ingly increasing probability of escape for any given ployed as roofing material for tents, pavillions and other light ray results in a more even distribution of light temporary structures.

escaping from optical branch 168'. Utilization devices other than converters for produc Additional modifications to the LEC 154 described in ing electricity may be connected to the solar collection connection with FIGS. 8 and 9 will become apparent to panels of the present invention. Indeed, the ability to those skilled in the art. Unwanted wavelengths of light manufacture solar collection panels and lightpipe deliv can be excluded from the LEC by employing a multiple ery systems for transmitting electromagnetic radiation layer interference film or an optical filter in conjunction to various remote sites opens up the possibility of devel with the optical window 178 of optical tree 162. A more oping entire classes of fixtures and appliances which desirable distribution of light within the optical tree 35 operate with optical energy rather than electrical en may be achieved by replacing optical window 178 with ergy. FIGS. 10 through 17 illustrate several such fix a plain lens, a Fresnel lens or a graded parabolic refrac tures and appliances for receiving and applying various tive indexed rod lens. Curved, mirrored sections 180 of combinations of visible and infrared radiation. For the trunk portion 166 may be replaced by appropriately sake of convenience, it may be assumed that the infrared angled flat mirrors, segmented mirrors, or right-angle 40 and visible radiation are solar in origin, and are col prisms. The top and bottom surfaces 172 of each optical lected by the solar collection panels illustrated in FIGS branch 168 may be flat or curved, and the surfaces may 1A through 5. However, the devices of FIGS. 10 have grooves or other mechanical deformations ar through 17 are not dependent upon solar energy for ranged thereon to distribute light in a more desirable operation, and any source of electromagnetic radiation, pattern across the solar cell arrays 164. The grooved 45 including radiation emitted from combustion processes, optical glass elements 194, 196 depicted in FIG.9 may incandescent light bulbs or lasers may actually supply be integrally combined with photochemical glass sheets the operating power.

184 as a means of reducing the number of optical ele The basic design for a heat distributing element is ments in each LEC compartment. Alternately, the shown in FIG. 10. The heat distributing element 202 grooved optical glass elements may be replaced by 50 consists of a single piece of quartz or other high melting other types of lens elements or eliminated altogether. point substance transparent to infrared radiation. The Both the mirrored ends 182 of optical branches 168 in infrared radiation is supplied to heat distributing ele FIG. 8 and the mirrored surfaces 200 positioned at the ment 202 through a lightpipe 204 connected to a solar terminus of compartments 160 in FIG.9 may be fabri collection panel employing a multiple layer interference cated in concave or convex curved fashion to further 55 film of the type disclosed in the above-mentioned U.S. enhance the distribution of light across solar cell arrays Pat. No. 3,314,331 issued to Wiley. The infrared radia 164. Finally, the optical tree 162 of FIGS. 8 and 9, tion is conducted from a suitable lightpipe coupling including the trunk portions and optical branches, may means 206 into a rod-shaped stem section 208 of heat be constructed as a hollow chamber rather than in the distributing element 202. Stem section 208 has a diame form of a solid, single piece of optical grade plastic. 60 ter slightly greater than the diameter of light pipe 204 Such a chamber would have highly reflective interior and is coated with a material which internally reflects walls corresponding to reflective surfaces 170 and the infrared radiation. Surface 210 of stem section 208 is transparent or beam splitting optical windows along the made optically transmissive to form an optical input areas corresponding to transparent surfaces 172. window through which radiation enters the heat distrib Another promising area of endeavor with regard to 65 uting element. A heat radiating section 212 is formed at the present invention lies in adapting the LEC's of the end of stem section 208 opposite input optical win FIGS. 6 through 9 for use in marine environments. An dow 210 by pitting or otherwise mechanically deform array of water tight non-metallic solar collection panels, ing the outer surface of the heat distributing element to 17 permit infrared radiation entering stem section 208 to Other configurations of heat distributing elements, escape into the surrounding atmosphere. Ideally, the however, can provide relatively high temperatures for spacing of the pitting is arranged such that the input industrial applications. FIG. 13 illustrates one possible radiation is uniformly emitted across the entire surface embodiment of a furnace for melting scrap metal, of heat radiating section 212. wherein heat distributing elements of the present inven It can be seen that stem section 208 serves as both an tion are used to heat the contents of the furnace. The optical mixer and a separator between heat radiating furnace includes a furnace chamber 244 lined with fire section 212, which may become quite hot, and the opti brick 246, a hatch 248 for inserting metal ingots or scrap cal coupling means 206, which may not be able to with O metal 250 into furnace chamber 244, and an outside stand much heat. Radiation entering stem section 208 is supporting shell (not shown). The floor 252 of the fur generally trapped inside by total internal reflection and nace is wedge or cone shaped and serves to funnel mol can only escape upon reaching heat radiating section ten metal into a channel 254 at the furance bottom. 212 and passing through the various pits or deforma Molten plug metal can thereafter be extracted by removing a means 256 from the channel. A plurality of heat tions. Heat radiating section 212 is depicted as being bulbous in shape, but in reality may be formed to fit any 15 distributing element 258 similar to heat distributing useful configuration. For example, heat radiating sec arranged around envelope the furance floor 252 to provide direct tion 212 may be elongated with a diameter equal to the thermal contact with the lower layer of metal 250. In diameter of stem section 208. A heat distributing ele frared radiation furnishes the heat to melt the metal, and ment having an elongated heat radiating section could 20 is supplied to the heat distributing element/envelope then be curved to form cylinders which wrap around combinations 258 via a lightpipe delivery system 260. containers, water pipes, or other volumes to be heated. Each individual lightpipe and heat distributing element On the other hand, a spherically or flat shaped heat envelope combination functions in a manner anaglous to radiating section may be more advantageous for heating that previously described in connection with FIGS. 10 devices such as space heaters or evaporators. 25 through 12 to provide high temperature heat transfer FIG. 11 illustrates a heat-transfer housing for use in conjunction with the heat distributing element of FIG. between the heat distributing element/envelope combi nations 258 and the metal 250. If desired, additional 10. The heat distributing element, indicated at 214 in radiant heat can be supplied to the contents of the fu FIG. 11, again receives infrared radiation from a solar rance by focusing high intensity light on the metal collection panel through a lightpipe 216 and lightpipe 30 through one or more lens systems 262. Lens systems 262 coupling means 218. The heat radiating section 220 of are mounted in cone shaped metal housings 264 on the heat distributing element 214 is surrounded by an enve sides of the furance and receive infrared radiation from lope 222 constructed of a high melting point metal such lightpipes 266. A series of cooling fins 268 can be as tungsten or titanium. Infrared radiation escaping formed around metal housings 264 to aid in keeping lens from heat radiating section 220 heats envelope 222, in systems 262 and the associated lightpipe coupling ar turn causing a net heat transfer to whatever object or rangements (not shown) as cool as possible. Auxiliary material is placed in contact with the envelope. An heat may also be supplied to the furance by a natural gas insulating base 224 formed from an insulating material burner (not shown) or other conventional heating ele such as quartz or firebrick secures both envelope 222 ment in order to maintain the heating capacity of the and heat distributing element 214 in fixed relationship to 40 furnace during periods of little or no sunlight. one another. Base 224 forms a seal 226 near the bottom Another and somewhat different type of heat transfer of heat distributing element stem section 228 in order to device constructed in accordance with the present in provide as much thermal insulation as possible between vention is embodied in the hand-held welder 270 for envelope 222 and the heat distributing element. The underwater use as illustrated in FIG. 14. Welder 270 space between envelope 222 and heat distributing ele 45 comprises a pistol-shaped housing 272 fabricated from ment 214 may be vacuum filled to furnish additional metal, glass, plastic or other durable material. Where thermal insulation. glass or plastic material is employed, the housing can be FIG. 12 illustrates another variation of a heat distrib made transparent to assist in locating damaged welder uting element constructed in accordance with the pres components. Solar heat radiation such as infrared radia ent invention and suitable for use in space heaters and 50 tion is conducted from a solar collection panel (not the like. Infrared radiation from a solar collection panel shown) through a lightpipe 274 to a lightpipe coupling and interference film assembly (not shown) is con means 276 and enters the welder via an optical input ducted into an elongated heat distributing element 230 window means 278 constructed from glass or other through lightpipe 232 and coupling means 234. An elon optical grade material. The sides of optical input win gated envelope 236 surrounds heat distributing element 55 dow means 278 contain mirror coatings while the trans 230 to provide a heat transfer surface. Heat distributing mission faces are transparent with curved lens like sur element 230 is given a reflective coating 238 at the point faces. The optical input window means is secured to of contact 240 between envelope 236 and the heat dis housing 272 in a manner which prevents water from tributing element, thereby preventing the envelope entering the interior of the housing. A first lens element from receiving excessive radiation at the contact point. 60 284 mounted inside housing 272 focuses the radiation A small insulating base 242 separates heat distributing emerging from optical input window means 278 onto element 230 and envelope 236, and additionally pro the mirrored coating 286 of prism 288. Prism 288 in turn vides a structure for attaching lightpipe coupling means serves to bend the radiation through a second lens ele 234. The FIG. 12 embodiment of the heat distributing 65 ment 290 toward the optical output window means 292. element and envelope as just described is generally Radiation received at the optical output window means designed to produce relatively low temperatures and 292 is directed to the outside of welder 270 and focused consequently is particularly adapted for home heating at an external focal point F3 to form a point source of applications. radiation with an intensity sufficient to carry out the 18 welding operation. Either or both of the transparent means 344 and the series of lenses before radiating out of transmission faces 294, 296 on the optical output win the optical output window. If desired, a handle 346 can dow means 292 may be curved in lens-like fashion while be formed on housing 338 to permit a user to hand carry the sides of the optical output window means are mirror projection lamp 336.

coated. Additional lens elements such as 300 may be 5 FIG. 17 is a cross-sectional view of a recessed light placed inside housing 272 at points along the radiation ing fixture 348 as mounted in a ceiling panel of a home, path to further modify the directional and intensity store, office or other building. Fixture 348 comprises a characteristics of the radiation beam travelling through solid right angle prism 350 partially surrounded by a the welder. The tip. 302 of welder housing 272 may housing 352 and positioned in a hole 354 in the ceiling contain a colored transparent substance which will 10 panel 356. A plurality of spring clips 358 simultaneously assist the user in positioning welder 270 when illumi engage housing 352 and plaster ring 360 formed around nated by stray rays of radiation such as R15 occasionally the periphery of hole 354, thereby fixedly securing omitted during the welding operation. fixture 348 to ceiling panel 356. A decorative face ring A trigger mechanism in the welder is employed to 362 may be attached to housing 352 to shield spring interrupt the transmission of radiation through the 15 clips 358 from view. Light enters the fixture through a welder housing 272 when desired. A first magnet 304 is light pipe 364 and lightpipe coupling means 366 and secured to a trigger 306 slidably mounted on the exte travels directly into the solid right angle prism 350. A rior of housing 272, and a spring 308 normally biases mirrored coating 368 on one side of prism 350 acts to trigger 306 in a fully extended position. A second mag redirect all of the input light toward opening 354 and net 310 is reciprocally mounted in the interior of hous out into the room beneath the ceiling panel. Because ing 272 such that magnet 310 tracks the movement of light traveling through a lightpipe tends to emerge at magnet 304 when trigger 306 is depressed against the near perpendicular angles to the cut and polished ligh force of spring 308. A push-pull rod 312 interconnects tpipe face employed in conjunction with the lightpipe magnet 310 with a sliding mirror 314. Sliding mirror 314 coupling means, generally only small intensities of light is normally positioned in the radiant path between opti 25 would be projected into prism 350 at angles dispersed cal input window means 278 and prism 288 and thus from the optical axis of lightpipe 362. Accordingly, serves to reflect all incoming radiation back through the when using a light fixture such as fixture 348 for general optical input window means toward lightpipe 274. illumination purposes it is often desirable to spread light When trigger 306 is depressed, however, magnet 304 leaving the fixture out over a wider range of angles. To slides in a direction which causes magnet 310 and asso this end, a light redistribution disk or plate 370 is se ciated rod 312 to push sliding mirror 314 back into cured to the underside of prism 350. In the embodiment compartment 316, out of the way of the incoming radia of FIG. 17 redistribution disk 370 exhibits a cross-sec tion. Thereafter, an unobstructed radiant path is formed tional profile having a relatively high convex curvature between optical input window means 278, first lens around the disk center with flatter or even slightly element 284, prism 288, second lens element 290, optical 35 concave surfaces near the disk edges. Other redistribu output window means 292 and radiation focal point F3. tion schemes such as those employing Fresnel lenses, Spring 318 is used to bias magnet 310 and sliding mirror however, may be used in lieu of disk 370. The ultimate 314 toward the normal interrupting or non-operating criterion for choosing a particular disk is one of conve position. An adjustment screw 320 may be used to ad nience, and the only constraint imposed is that of gener just the tension of spring 318. 40 ating a wide enough dispersion for uniform radiation Three different types of lighting fixtures suitable for from the fixture.

connection via lightpipes to the solar collection panels A number of modifications to the recessed lighting of the present invention are shown in FIGS. 15, 16, and fixture of FIG. 17 are possible. Prism 350, for instance, 17. The lighting fixture 322 of FIG. 15 is a wide disper may be replaced by a mirror mounted at an appropriate sion lighting fixture which may be used in either land or 45 angle, or the lightpipe coupling means 366 could be undersea environments, and includes a bulb section 324 relocated at the top of the fixture to eliminate entirely joined to a short stem section (not shown). A housing the need for redirecting the light. A suitable light redis 326 surrounding the stem section rigidly supports bulb tribution disk, of course, would still have to be em section 324, and is linked to a clamp structure 328 by a ployed in such an arrangement. The entire recessed ball joint 330. The bulb and stem sections are fabricated 50 fixture could be rotatably mounted to vary the direction from a single piece of glass or plastic with translucent of light projection, and means for inserting colored characteristics such that light travelling through the transparent filters in the path of the outgoing light could glass or plastic is thoroughly diffused and emerges ran be provided to add a decorator touch. domly in all directions from lighting fixture section 322. In some applications, it may be desirable to furnish The surface of bulb section 324 may additionally be 55 lighting fixtures which can distribute either light deliv sandblasted or otherwise mechanically deformed to ered via lightpipe means or light generated within the further diffuse the emitted light. A lightpipe coupling fixture itself by conventional electrical means. Combi means 332 joined to the stem section at the bottom of nation fixtures of this type could use solar light by day housing 326 serves to couple light radiation arriving and artificial light by night. Several methods of adapt from a solar collection panel (not shown) through ligh 60 ing different light sources for projection to the same tpipe 334. The clamp and ball joint structure provides output means are possible. One method employs a com versatility in securing and adjusting lighting fixture 322 plex reflector structure having three focal points. The relative to the area being illuminated. output from a lightpipe is focused at one focal point and FIG. 16 illustrates a portable projection lamp 336 the output from an artificial light source is focused at a including a housing 338 with a series of one or more 65 second focal point. In either case, light is subsequently internally-mounted lenses (not shown) and an optical reflected to the third focal point for transmission output window 340. Light from a solar collection panel through a conventional projection or light dispersion is conducted through lightpipe 342, lightpipe coupling means into the room or area to be illuminated. Tri-focus 19 reflectors are typically made with two elliptical reflec 7. A converter apparatus as set forth in claim 1 tors having a common focus which serves as the third wherein said light conducting fabric means is a woven or output focus just described. A second method of fabric having warp and woof strands, one of which is alternating the use of artificial and solar light is based formed by said plurality of optical fibers and the re upon channeling the artificial light into a lightpipe mainder of which is formed by a plurality of optically which subsequently merges in an optical merge device inert fibers.

with a lightpipe carrying solar radiation. The combined 8. A converter apparatus as set forth in claim 7, lightpipe is then connected to one of the lighting fix wherein said plurality of optically inert fibers consist of tures illustrated in FIGS. 15 through 17. a plurality of thin metallic wires. Several embodiments of the present invention have O 9. A converter apparatus for transforming light into been specifically shown and described herein. It is un electricity, comprising:

derstood as well that additional changes and modifica (a) a housing structure enclosing at least one compart tions to the form and detail of the various solar collec ent tion and utilization devices illustrated above may be 15 (b) solar cell means mounted within said compartment made by those skilled in the art without departing from for generating electricity from light; the scope and spirit of the present invention. It is thus (c) a light collection means remote from said housing the intention of the inventor to be limited only by the structure for collecting light, said light collection following claims. means including at least one radiation gathering I claim: means for gathering electromagnetic radiation inci 1. A converter apparatus for generating electricity in 20 dent thereon, each said radiation gathering means response to light received, said converter apparatus including a plurality of individual cell structures each comprising: of which has a focusing means for focusing electro (a) a housing structure enclosing at least one compart magnetic radiation incident thereon into a beam of ment; 25 electromagnetic radiation and cell optical window (b) solar cell means mounted within said compartment means positioned to receive said beam of radiation; for generating electricity from visible radiation and (d) light transmission means positioned to receive the (c) light conducting means connected to said housing beam of radiation from said cell optical window structure for conducting light to the interior of said means and operative to conduct said beam of radia compartment, said light conducting means including 30 tion as light to the interior of said compartment in a light transmissive surface within said compartment said housing structure; and through which visible radiation can escape to im (e) a light distribution means within said compartment pinge upon said solar cell means, said light conduct connected to receive light from said light transmis ing means including a light conducting fabric means sion means and operative to direct said light onto said for providing said light transmissive surface, said 35 solar cell means.

light conducting fabric means including a plurality of 10. The converter apparatus of claim 9 wherein said optical fibers each adapted to transmit light along the light transmission means includes radiation gathering length thereof outwardly at an angle to the longitudi means for receiving the beam of radiation from the cell nal axis thereof. optical window means, said radiation gathering means 2. A converter apparatus as set forth in claim 1, 40 including a plurality of separate optical output windows wherein said housing structure is divided into a plural and operating to transmit the radiation received thereby ity of compartments, said solar cell means includes a to at least one of said plurality of separate optical output plurality of solar cell arrays respectively mounted windows.

within said plurality of compartments, and said fabric 11. The converter apparatus of claim 10 wherein said means includes a plurality of light emitting fabric pieces 45 light transmission means includes light conducting respectively positioned adjacent each said solar cell means having an input end for receiving light and oper array. ative to conduct light received at said input end to said 3. A converter apparatus as set forth in claim 2, light distribution means, and concentrating means oper wherein a photochemical glass sheet is inserted between ative to receive the radiation from the plurality of sepa each said solar cell array and light emitting fabric piece. 50 rate optical output windows of said radiation gathering 4. A converter apparatus as set forth in claim 1 means and to focus the radiation from said plurality of wherein said light conducting means includes a ligh separate optical output windows onto the input end of tpipe connected between a remote light collection de said light conducting means as a single beam of radia vice and said housing structure. tion.

5. A converter apparatus as set forth in claim 1, 55 12. The converter apparatus of claim 9 wherein said wherein said housing structure includes a series of ex light transmission means includes light conducting ternal cooling fins which contact the air and transfer means operative to conduct light from said radiation heat thereto during the generation of electricity. gathering means to said light distribution means, said 6. A converter apparatus as set forth in claim 1, light conducting means including at least one optical wherein said fabric means includes a plurality of thin 60 fiber means for each said cell structure having one end metallic wires which are secured to the interior surfaces thereof positioned adjacent said cell optical window of said housing structure such that heat produced in the means, said optical fiber means receiving the beam of interior of said housing structure during the generation radiation from said cell optical window means. of electricity is conducted to the interior surfaces of said 13. The converter apparatus of claim 12 wherein said housing structure via said thin metallic wires and there 65 cell optical window means includes an aperture, said after transfers to the exterior surfaces of said housing aperture being bounded by curved reflecting surfaces structure for dissipation into the surrounding atmo diverging outwardly from said aperture away from the sphere. end of said optical fiber means.

Page 20scan →

14. The converter apparatus of claim 9 wherein said external, light transmissive surface formed thereon light distribution means includes a light conducting adjacent said solar cell means to form said light trans fabric means for providing light to said solar cell means, missive surface means; and said light conducting fabric means including a plurality (d) a photochemical glass sheet positioned between said of optical fibers each adapted to transmit light along the 5 branch portion and said solar cell means length thereof outwardly at an angle to the longitudinal 21. A converter apparatus for generating electricity axis thereof. in response to light received, comprising: 15. A converter apparatus for generating electricity (a) housing structure enclosing at least one compart in response to light received, comprising: ment;

(a) a housing structure enclosing a plurality of separate 10 (b) solar cell means mounted within said compartment compartments, said housing structure including light for generating electricity from visible radiation; and input means for conducting light into said housing (c) light conducting means connected to said housing structure and electrical outlet means for conducting structure for conducting light to the interior of said electricity from said housing structure; compartment including a light transmissive surface (b) solar cell means mounted within each of said com 15 within said compartment through which visible radi partments for generating electricity from light re ation can escape to impinge upon said solar cell ceived thereby; means, said light conducting means including an opti (c) light distribution means in each of said compart cal tree means secured within said housing structure ments connected to receive light from said light input for receiving and distributing light, said optical tree means and operative to direct light onto said solar means having a trunk portion and at least one branch cell means; and portion extending from said trunk portion into said (d) an electrical conducting means connected between compartment, said branch portion having an external, the solar cell means in each said compartment and light transmissive surface formed thereon adjacent said electrical outlet means for conducting electricity said solar cell means to provide said light transmissive generated by said solar cell means. 25 surface, the remaining exterior surfaces of said branch 16. The converter apparatus of claim 15 wherein light portion and the exterior surfaces of said trunk portion intensity control means are positioned between the light being covered with an internally reflective mirror distribution means and the solar cell means in each said coating.

compartment, said light intensity control means includ 22. A converter apparatus as set forth in claim 21, ing a transparent sheet which darkens in response to wherein said solar cell means includes first and second high intensity light to protect said solar cell means. solar cell arrays respectively mounted on the top and 17. The converter apparatus of claim 16 wherein a bottom of said compartment, and said branch portion solar cell means is positioned on opposite sides of said has two external light transmissive surfaces respectively light distribution means within each said compartment. formed on the top and bottom thereof adjacent said first 18. A converter apparatus as set forth in claim 15, and second solar cell arrays.

wherein said light distribution means includes an optical 35 23. A converter apparatus as set forth in claim 22, tree means secured within said housing structure for wherein the light transmissive surface of said branch receiving and distributing light from the light input portion is tapered within said compartment. means, said optical tree means having a trunk portion 24. A converter apparatus as set forth in claim 22, and at least one branch extending from said trunk por wherein said housing structure is divided into a plural tion into each said compartment, said branch portion ity of compartments each having a solar cell means having an internal, light transmissive surface formed mounted therein and said optical tree means includes a thereon adjacent said solar cell means, and the remain plurality of branch portions which extend from said ing exterior surfaces of said branch portion and the trunk portion into each of said compartments. exterior surfaces of said trunk portion being covered 45 25. A converter apparatus for generating electricity with an internally reflective mirror coating. in response to light received, thereby comprising: 19. A converter apparatus as set forth in claim 18, (a) a housing structure enclosing at least one compart wherein said solar cell means includes first and second ment;

solar cell arrays respectively mounted on the top and (b) solar cell means mounted within said compartment bottom of each said compartment and said branch por for generating electrictiy from visible radiation; tion has two external, light transmissive surfaces adja 50 (c) light conducting means connected to said housing cent said first and second solar cell arrays. structure for conducting light to the interior of said 20. A converter apparatus for generating electricity compartment including a light transmissive surface in response to light received, comprising: within said compartment through which visible radi (a) a housing structure enclosing at least one compart ation can escape to impinge upon said solar cell ment; 55. means, said light conducting means including an opti (b) solar cell means mounted within said compartment cal tree means secured within said housing structure for generating electricity from visible radiation; for receiving and distributing light, said optical tree (c) light conducting means connected to said housing means having a trunk portion and at least one branch structure for conducting light to the interior of said portion extending from said trunk portion into said compartment and including a light transmissive sur 60 compartment, said branch portion having an external, face means within said compartment through which light transmissive surface formed thereon adjacent visible radiation can escape to impinge upon said said solar cell means to provide said light transmissive solar cell means, said light conducting means includ surface, said light transmissive surface of said branch ing an optical tree means secured within said housing portion being tapered within said compartment; and structure for receiving and distributing light, said 65 (d) a grooved optical element positioned between the optical tree means having a trunk portion and at least external, light transmissive surface of said branch one branch portion extending from said trunk portion portion and said solar cell:k array. into Said compartment, said branch portion having an sk sk k ck