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IL122390A - Optical surface device - Google Patents

Optical surface device

Info

Publication number
IL122390A
IL122390A IL12239097A IL12239097A IL122390A IL 122390 A IL122390 A IL 122390A IL 12239097 A IL12239097 A IL 12239097A IL 12239097 A IL12239097 A IL 12239097A IL 122390 A IL122390 A IL 122390A
Authority
IL
Israel
Prior art keywords
light
fiber
layer
optical
layers
Prior art date
Application number
IL12239097A
Other versions
IL122390A0 (en
Inventor
Zamir Tribelsky
Michael Ende
Original Assignee
Atlantium Lasers Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Atlantium Lasers Ltd filed Critical Atlantium Lasers Ltd
Priority to IL12239097A priority Critical patent/IL122390A/en
Publication of IL122390A0 publication Critical patent/IL122390A0/en
Priority to PCT/IL1998/000587 priority patent/WO1999028673A1/en
Priority to AU14452/99A priority patent/AU1445299A/en
Publication of IL122390A publication Critical patent/IL122390A/en

Links

Classifications

    • GPHYSICS
    • G02OPTICS
    • G02BOPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0005Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being of the fibre type
    • G02B6/001Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being of the fibre type the light being emitted along at least a portion of the lateral surface of the fibre

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Non-Portable Lighting Devices Or Systems Thereof (AREA)
  • Optical Couplings Of Light Guides (AREA)

Abstract

An optical surface device comprising at least one side emitting optical fiber (1) integrated in between at least two layers (34) of multi layer optical laminations for the diffusing of light as illumination or for collecting external light and concentrating it into said side emitting optical fiber, the fiber being convoluted between the two layers for effective distribution of the fiber over the layer's area, the device is characterized by at least one of the following: (a) the optical surface device for collecting exterior light and the optical surface device for diffusing the light are hybridized such that light concentrated into a fiber by the first device, is shunted into the other device through a continuation of the same fiber, for diffusion of the light in a remote location; (b) the at least two layers having the at least one side emitting optical fiber integrated in between are tinted in two different colors to form a dichroic mirror or filter, wherein at least one of each of said fibers' end portions either is accessible for receiving light from at least one light source unit or is accessible for transferring light to at least one light emitting unit. 1782 ז' באב התשס" ד - July 25, 2004

Description

^six ntwb |i?nn AN OPTICAL SURFACE DEVICE FIELD OF THE INVENTION The present invention generally relates to an optical surface device, which is especially usefully integrated into multi layer optical laminations for the diffusing of light as illumination or for the concentrating of light. More specifically, the present invention relates to an optical surface device having held- in-place convoluted (effectively surface covering) side emitting optical fiber (s) .
The device of the present invention is useful as an illumination device when artificial light from a light source is aligned into the fibers for diffusing the light out from the surface (spatial dimensional lighting) .
The device of the present invention is also useful for the collection of light (especially sun light) which illuminates the convoluted surface covering fiber (s) and is transferred by these fibers into a region of optical concentration (being a cross-section without certain properties of a focal point) .
BACKGROUND OF THE INVENTION Prior art US 5,542,016, US 4,510,555, US 4,885,663 and US 5,690,408 disclose different embodiments of an illuminating surface which basically consist of optical fibers arranged in a repeating recurrent pattern (spiral, zig-zag or a woven mate) and sandwiched between two transparent surfaces or between a reflector and a diffuser surfaces. Neither of these patents disclose a light collector and concentrator device .
US 5,431,742 discloses a solar radiation concentrator for the purpose of generating electrical power. In said patent however, the optical fiber consists of laser material, which is capable of converting solar energy into laser radiation, needed for generating the electrical power. The purpose of the present invention is collecting of light for illuminating in remote locations with the same light without conversion.
BACKGROUND OF THE INVENTION The device of the present invention in general relates to two symmetrically opposite functional embodiments. These embodiments are the optical surface for the diffusion of light (the "illuminator" embodiment) and the optical surface for the collection of (ambient) light (the "concentrator" embodiment) . Each of these two general embodiments requires a different basis of understanding in order to recognize their operating principles and to appreciate their useful applications.
The illuminator embodiment allows large surface area to be used as environmental lighting sources. This has (in the past) been done either by installing a plurality of small light sources (e.g. electric bulbs) onto a substrate (often behind an opaque screen) or by projecting the light from a high intensity light source onto a substrate (screen) using an apparatus of mirrors and/or lenses. Prior art methods have not allowed for the cost efficient uniform illumination of very large surfaces (e.g. entire ceilings, inter-folded hanging draperies, or complex aerodynamic manifolds), while the device of the present invention easily accommodates such applications .
The concentrator embodiment allows large surface areas to be used for the collection of ambient radiation, especially sun light. This has (in the past) been accomplished using expensive lens or mirror apparatus, often with complex computer controlled engines for correcting the tracking angles of the optical element in order to optimize focusing of the collected light. Prior art methods have not allowed for the cost efficient use of large surface collectors (e.g. the exterior wall of a building, or the fixed angle support of a roof), while the device of the present invention easily accomplishes such applications (without any need for sun tracking engines and the like) .
Today, multi layer optical laminations include such diverse products as: (a) Safety glass (made from alternate bonding of glass and plastic layers). (b) Rear surface mirrors (made from a reflective layer deposited onto a transparent glass or plastic layer) . (c) Dichroic surfaces (made from the deposition of two different color tints onto opposite sides of a layer of glass or plastic; or made from two layers of glass or plastic which are tinted in different colors and which have been bonded together). (d) Non-glare glass (made by coating a glass or plastic layer with a intermediary optic index material ) . (e) Frenel lenses or diffraction gratings (made by the regular geometric convolution etching of surface distortion onto an optical surface substrate). (f) Morie interference surface optical elements (usually made by bonding together two similar layers of Frenel lenses or diffraction gratings - according to the aforesaid general definition) (g) Complex chromatic aberration reducing lenses (made by bonding together the convex side of a lens of optical index "A" with the mated concave side of a lens of optical index "B"), sun screens (made by bonding together thin films of differing optical properties).
The preferred embodiments of the device of the present invention introduces a surface like element of side emitting optical fiber (s) (especially into the interstitial bonding region of multi layer optical laminations) in order to accomplish the illuminator and concentrator application embodiments. This use of side emitting optical fibers as an active element in optical laminations has not heretofore been exploited for either type of embodiment. Furthermore, the device of the present invention finds novel cost efficient usefulness in these numerous applications.
SUMMARY OF THE INVENTION The present invention relates to an optical surface device especially usefully integrated into multi layer optical laminations for the diffusing of light as illumination or for the concentrating of light. The device of the present invention is comprised of (a) at least one side emitting optical fiber and the fiber is convoluted to effectively cover a surface area, and (b) means for holding the fiber in the surface area covering convolution. Furthermore, at least one of each of the fibers' end portions either is accessible for receiving light from at least one light source unit (for the illuminator embodiments) or is accessible for transferring light to at least one light emitting unit (for the concentrator embodiments).
DETAILED DESCRIPTION OF THE INVENTION For purposes of the present invention (when the device of the present invention is embodied for illumination), a "side emitting optical fiber" is any optical fiber which will transmit a desired frequency of light from one end to the other (using internal reflection of the fiber), and simultaneously allows some portion of the transmitted light to escape from the fiber during the transmission along the length. This escape of light preferably is continuous along the entire length of the fiber, but may be restricted to a plurality of ("exposed") locations along the fiber.
For purposes of the present invention (when the device of the present invention is embodied for light collection), it is equivalent to define the side emitting optical fiber as any optical fiber which will transmit a desired frequency of light from one end to the other (using internal reflection of the fiber), and simultaneously allows some portion of ambient light to enter the fiber and there to be transmitted internally along the length. This entry of light into the fiber preferably is continuous along the entire length of the fiber, but may be restricted to an ensemble (very large number) of ("exposed") locations along the fiber or to a plurality of ( "exposed" ) locations along the fiber which are positioned at predictable, periodic, or geometrically significant co-ordiantes of the optical surface.
Furthermore, in the context of the present invention "convoluted to effectively cover a surface area" generally relates to a pattern of parallel fibers where the average distance between the fibers is selected according to the maximum optical flux density of the embodiment .
For example, in the context of an optical surface device for illumination, a zig-zag pattern of fiber across the entire surface, a spiral pattern of fiber across the entire surface, and a spiral of zig-zaging fiber across the entire surface all constitute an effective coverage. The spatial freguency of this effective coverage (being the average distance between a fiber portion and it's nearest neighbor fiber portions - within predetermined tolerance limits) determines the relative optical flux density of each fiber portion with respect to the total length of fiber (for continuous side emitting fibers).
A randomized distribution of fiber over a surface area within predetermined spatial frequency limits also constitutes effective coverage, especially for embodiments using fibers having a plurality of exposed locations .
In the context of an optical surface device for the collection (and subsequent concentration) of light, the tolerance of spatial frequency extrema generally demands that the resultant convolution more closely resemble an actual surface (with only tiny holes or slits). However, where the collection embodiment is only for the purposes of filtering (regardless of the desired concentration efficiency) , then the convolutions may be identical to those of the illumination embodiment.
For purposes of the present invention "multi layer optical laminations" relates to bonding together optical materials (e.g. glass or plastic layers which are, transparent, opaque, frosted, tinted, partially reflective, diffraction grated, interference producing, holographic, phosphorescent, or fluorescent) using heat, pressure, adhesives, or structural relative-position stabilizing members. These layers may be rigid (e.g. flat, corrugated, parabola shaped, sphere shaped, complex surfaces, surfaces having a plurality of protruding members, etc.) or flexible (e.g. thin films stored or distributed rolled up onto cylinders).
The present invention relates to an optical surface device, which is especially usefully integrated into multi layer optical laminations for the diffusing of light as illumination or for the concentrating of light. The optical surface device of the present invention is comprised of at least one side emitting optical fiber and the fiber is convoluted to effectively cover a surface area, and means for holding the fiber in the surface area covering convolution, wherein at least one of each of the fibers' end portions either is accessible for receiving light from at least one light source unit or is accessible for transferring light to at least one light emitting unit.
According to the preferred embodiment of the illuminator embodiment of the present invention, the optical surface device has at least one light source for aligning light into the optical fibers' end portion.
According to a basic embodiment of the device of the present invention, the side emitting optical fiber is laminated onto a rigid or flexible optical surface. According to the preferred embodiments (both illuminator and concentrator) of the present invention, the side emitting optical fiber is laminated between two optical surfaces. These optical surface may be glass or plastic.
These optical surfaces may be transparent, opaque, frosted, tinted, partially reflective, diffraction grated, interference producing, holographic, phosphorescent, or fluorescent. In laminations having two optical surfaces, the two optical surfaces may be tinted in different frequencies forming a dichroic mirror. According to another basic embodiment of the device of the present invention, the side emitting optical fiber is laminated onto a reflective optical surface.
Furthermore, according to the preferred basic embodiments of the device of the present invention, the means for holding (the fiber in the surface area covering convolution) is using an adhesive or an integrating binder. According to the preferred embodiment of the optical surface device, the optical fiber is a graded index fiber.
An example of the formation of an illuminator embodiment according to the present invention relates to integrating the convoluted held-in-place surface layer of side emitting optical fiber (s) between two layers of thin plastic film, wherein one of these film layers has a deposition of anodized aluminum. This active reflector film laminate embodiment of the device of the present invention may then be used as wall paper, as curtains, or may even be "shrink wrapped" onto sports cars or aircraft wings. When the laminate's accessible incorporated fibers' end portions are connected for receiving light from at least one light source unit, then the entire laminate serves to distribute the light from the source unit into the regions opposite the transparent layer of the laminate.
Another example of the formation of an illuminator embodiment according to the present invention relates to the use a rigid layer in addition to (or as a substitution for at least one of the thin film layers of the previous example. This embodiment results in rigid illuminator members which may be used as interior partitions, windows, ceilings, or walls.
An example of the formation of a concentrator embodiment according to the present invention relates to a stationary flat plate solar energy collector for placement on roof tops (being normally oriented about toward the equator at about a latitude determined angle) . This embodiment is comprised of a first slightly opaque layer, a surface covering convolution of side emitting optical fiber layer, a second slightly opaque layer, a reflective layer, and a structural support layer if the prior layers are not collectively rigid.
Sun light enters the first slightly opaque layer and the angle of the sun light is randomized because of the opacity. Most of the sun light then proceeds into the fiber layer where a portion of the sun light enters into the fiber through the fiber walls at an angle sufficient for this light to proceed within the fiber along the fiber's axis (core). Most of the sun light which does not enter the fiber then proceeds into the second slightly opaque layer where the angle is again randomized. Most of this light is then bounced off of the reflective layer, is again randomized by the second slightly opaque layer, and is given a second chance to enter into the fiber at an acceptable angle. This optical process scenario also has many harmonics, cycles, and other second order interactions .
The majority of the sun light which enters into the side emitting optical fiber is then concentrated at the fibers' end portion where it is accessible for transfer to at least one light emitting unit (often using a standard end emitting optical fiber).
Another example of the formation of a concentrator embodiment according to the present invention relates to a transparent dichroic filter window laminate comprising a exterior layer of ultra-violet filtering glass, a surface covering convolution of side emitting optical fiber central layer, and an interior layer of infra-red filtering glass.
The result for the observer from the interior side of the window is a window which only allows visible light to enter and which has slight optical distortions due to the central fiber layer.
The result from the perspective of the fibers 1 end portion is an accessible concentration of visible and infra-red light for transfer to at least one light emitting unit (often using a standard end emitting optical fiber) .
This concentrated visible and infra-red light may be distributed elsewhere (e.g. in the building's interior) using one of the illuminator embodiments of the device of the present invention. The use of a collector embodiment shunting it's concentrated light into an illuminator embodiment is the preferred hybrid embodiment of the device of the present invention.
Another example of the formation of a hybrid concentrator-illuminator embodiment according to the present invention relates to the use of a high efficiency light source for the illumination of a very large area (such as an entire amphitheater, shopping center, convention center, etc.)- This hybrid embodiment is comprised of a high efficiency light source projecting its light through a plurality of surface covering convolution of side emitting optical fiber layers (collectors), with the accessible end portion of each fiber layer shunting it's concentrated light into a corresponding illuminator (at remote locations).
This hybrid embodiment allows (a) energy savings which results from the use of a high efficiency light source, (b) savings due to the reduced cost of illuminator installation without any electricity installation, and (c) eliminates the cumbersome maintenance costs heretofore required for the changing of light bulbs in a plurality of lighting fixtures.
The present invention will be further described and clarified in detail by Figures 1-3. These figures are solely intended to illustrate the preferred embodiment of the invention and are not intended to limit the scope of the invention in any manner.
Figure 1 illustrates a schematic perspective view of an optical laminate containing a central optical fiber surface covering layer.
Figure 2 illustrates a schematic exploded perspective view of an optical laminate containing two optical fiber surface covering layers .
Figure 3 illustrates a schematic exploded perspective view of an optical laminate containing a central optical fiber surface covering layer.
Figure 1 illustrates a schematic perspective view of an optical laminate containing a central optical fiber surface covering layer. At least one side emitting optical fiber (1) is convoluted to effectively cover a surface area. This fiber is held in the surface area covering convolution by adhesive to a substrate glass plate (2). One end portion (18) of the fiber is accessible either for receiving light from at least one light source unit (illuminator embodiment) or for transferring light to at least one light emitting unit (concentrator embodiment). The glass substrate forms the central layer of an optical surface lamination, being between a plastic plate (3) and a mirror-like reflective plate (4). This figure also helps to visualize the constructor of a basic illuminator embodiment or a transparent dichroic filtering window embodiment.
Figure 2 illustrates a schematic exploded perspective view of an optical laminate containing two optical fiber surface covering layers . An exploded five layer laminate is shown having a three transparent glass layers (5) (7) (9) and two thin film substrate layers (6) (8) The first substrate layer (6) has a surface covering side emitting optical fiber (10) with an exposed end portion (19). The second substrate layer (8) has a surface covering side emitting optical fiber (11) with an exposed end portion (20). This figure also helps to visualize a collector embodiment for use with a high efficiency light source.
Figure 3 illustrates a schematic exploded perspective view of an optical laminate containing a central optical fiber surface covering layer. A five layer laminate is shown having a first protective coating layer (12), a second opaque layer (13), a third thin film substrate layer (14), a forth opaque layer (15), and a fifth reflective layer. The third layer's surface is covered with a high density of side emitting optical fiber (21) having an exposed end portion (17). This illustration helps to visualize a solar radiation collector concentrator embodiment, or a complex illuminator embodiment. In the context of a complex illuminator embodiment, the second layer may be completely or partially diffraction grated, interference producing, holographic, phosphorescent, or fluorescent. This modified second surface layer is useful as an artistic illuminated advertisement sign. Alternatively, having a first layer including a large frenel lens allows a flat illuminator embodiment to be used as a spot light. 122390/3

Claims (19)

1. An optical surface device comprising at least one side emitting optical fiber integrated in between at least two layers of multi layer optical laminations for the diffusing of light as illumination or for collecting external light and concentrating it into said side emitting optical fiber, the fiber is convoluted between the two layers for effective distribution of the fiber over the layer's area, the device is characterized by at least one of the following; (a) the optical surface device for collecting exterior light and the optical surface device for diffusing the light are hybridized such that light concentrated into a fiber by the first device, is shunted into the other device through a continuation of the same fiber, for diffusion of the light in a remote location; (b) the at least two layers having the at least one side emitting optical fiber integrated in between are tinted in two different colors to form a dichroic mirror or filter, wherein at least one of each of said fibers' end portions either is accessible for receiving light from at least one light source unit or is accessible for transferring light to at least one light emitting unit. 122390/3
2. A device according to claim 1 having at least one light source for aligning light into the optical fibers' end portion.
3. A device according to claim 1 wherein the side emitting optical fiber is laminated onto a rigid or flexible optical surface.
4. A device according to claim 1 wherein the side emitting optical fiber is laminated between two optical surfaces.
5. A device according to claims 3 or 4 wherein the optical surface is glass or plastic.
6. A device according to claims 3 or 4 wherein the optical surface is transparent, opaque, frosted, tinted, partially reflective, diffraction grated, interference producing, holographic, phosphorescent, or fluorescent.
7. A device according to claim 1 wherein the side emitting optical fiber is laminated onto a reflective optical surface.
8. A device according to claim 1 further including means for holding the fiber in the surface area covering convolution .
9. A device according to claim 8 wherein the means for holding is using an adhesive or an integrating binder . 122390/3
10. A device according to claim 1 wherein the optical fiber is a graded index fiber.
11. A device according to claim 1 wherein a convoluted held-in-place surface layer of side emitting optical fiber (s) between two layers of thin plastic film, and one of these film layers has a deposition of anodized aluminum.
12. A device according to claim 11 wherein a convoluted held-in-place surface layer of side emitting optical fiber (s) between a thin plastic film layer and a rigid layer of glass or plastic, and one of these layers has a deposition of anodized aluminum.
13. A device according to claim 12 having a first slightly opaque layer, a surface covering convolution of side emitting optical fiber layer, a second slightly opaque layer, and a reflective layer.
14. A device according to claim 13 wherin the first layer, the fiber layer and the reflective layer are collectively non-rigid, further comprising a structural support layer, useful for making the layers collectively rigid.
15. A device according to claim 1 wherein the dichroic filter is used as a window.
16. Method for collecting light at a first location for further distributing it in remote location or locations, comprising exposing an optical surface 122390/3 device comprised of at least one side emitting optical fiber integrated in between at least two layers of multi layer optical laminations said fiber is convoluted between the two layers for effective distribution of the fiber over the layer's area, to an external source of light and making a side emitting fiber of the optical surface device accessible for transferring light to at least one light emitting unit.
17. An Optical surface device for the diffusing of light as illumination or for the concentrating of light, substantially as hereinbefore described and illustrated .
18. An illuminator device substantially as hereinbefore described and illustrated.
19. An concentrator device substantially as hereinbefore described and illustrated. For the Applicants EINHOLD COHN AND PARTNERS By :
IL12239097A 1997-12-01 1997-12-01 Optical surface device IL122390A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
IL12239097A IL122390A (en) 1997-12-01 1997-12-01 Optical surface device
PCT/IL1998/000587 WO1999028673A1 (en) 1997-12-01 1998-12-01 Optical panel with an optical arranged in a serpentine fashion
AU14452/99A AU1445299A (en) 1997-12-01 1998-12-01 Optical panel with an optical arranged in a serpentine fashion

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
IL12239097A IL122390A (en) 1997-12-01 1997-12-01 Optical surface device

Publications (2)

Publication Number Publication Date
IL122390A0 IL122390A0 (en) 1998-06-15
IL122390A true IL122390A (en) 2004-07-25

Family

ID=11070914

Family Applications (1)

Application Number Title Priority Date Filing Date
IL12239097A IL122390A (en) 1997-12-01 1997-12-01 Optical surface device

Country Status (3)

Country Link
AU (1) AU1445299A (en)
IL (1) IL122390A (en)
WO (1) WO1999028673A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006061164B4 (en) 2006-12-22 2018-12-27 Osram Opto Semiconductors Gmbh Light-emitting device
WO2016092576A1 (en) * 2014-12-09 2016-06-16 Vito Lavanga Method for distributing a uniform radiative spectrum and device for implementing said method

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4510555A (en) * 1984-02-27 1985-04-09 Kei Mori Ornamental lighting device
US4885663A (en) * 1988-03-22 1989-12-05 Lumitex, Inc. Fiber optic light emitting panel and method of making same
CA2121653C (en) * 1993-05-05 1997-05-13 Kevin D. Kaschke Optical fiber light emitting apparatus
US5431742A (en) * 1994-01-24 1995-07-11 Kleinerman; Marcos Y. Luminescent solar concentrators using light amplification processes
US5690408A (en) * 1996-09-23 1997-11-25 Mcdonnell Douglas Corporation Fiber optic based lighting for aircraft

Also Published As

Publication number Publication date
IL122390A0 (en) 1998-06-15
WO1999028673A1 (en) 1999-06-10
AU1445299A (en) 1999-06-16

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