GB2360868A - Low-profile Illuminators - Google Patents
Low-profile Illuminators Download PDFInfo
- Publication number
- GB2360868A GB2360868A GB0007786A GB0007786A GB2360868A GB 2360868 A GB2360868 A GB 2360868A GB 0007786 A GB0007786 A GB 0007786A GB 0007786 A GB0007786 A GB 0007786A GB 2360868 A GB2360868 A GB 2360868A
- Authority
- GB
- United Kingdom
- Prior art keywords
- illuminator
- illuminator according
- light
- transparent plate
- reflector
- Prior art date
- Legal status (The legal status 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 status listed.)
- Withdrawn
Links
- 239000004020 conductor Substances 0.000 claims description 12
- 238000009827 uniform distribution Methods 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 3
- 239000011248 coating agent Substances 0.000 claims description 2
- 238000010276 construction Methods 0.000 abstract description 2
- 230000001419 dependent effect Effects 0.000 abstract 1
- 238000000034 method Methods 0.000 description 7
- 239000000758 substrate Substances 0.000 description 5
- 239000011521 glass Substances 0.000 description 3
- 239000002184 metal Substances 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 1
- 238000005530 etching Methods 0.000 description 1
- 238000010304 firing Methods 0.000 description 1
- 239000005357 flat glass Substances 0.000 description 1
- 238000005286 illumination Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000011159 matrix material Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000004382 potting Methods 0.000 description 1
- 230000005855 radiation Effects 0.000 description 1
- 238000007650 screen-printing Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 238000005476 soldering Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000001228 spectrum Methods 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
Classifications
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F13/00—Illuminated signs; Luminous advertising
- G09F13/04—Signs, boards or panels, illuminated from behind the insignia
- G09F13/14—Arrangements of reflectors therein
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
- F21V23/00—Arrangement of electric circuit elements in or on lighting devices
- F21V23/04—Arrangement of electric circuit elements in or on lighting devices the elements being switches
- F21V23/0442—Arrangement of electric circuit elements in or on lighting devices the elements being switches activated by means of a sensor, e.g. motion or photodetectors
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21V—FUNCTIONAL FEATURES OR DETAILS OF LIGHTING DEVICES OR SYSTEMS THEREOF; STRUCTURAL COMBINATIONS OF LIGHTING DEVICES WITH OTHER ARTICLES, NOT OTHERWISE PROVIDED FOR
- F21V7/00—Reflectors for light sources
- F21V7/0008—Reflectors for light sources providing for indirect lighting
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
- G09F9/30—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements
- G09F9/33—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements being semiconductor devices, e.g. diodes
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F21—LIGHTING
- F21Y—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES F21K, F21L, F21S and F21V, RELATING TO THE FORM OR THE KIND OF THE LIGHT SOURCES OR OF THE COLOUR OF THE LIGHT EMITTED
- F21Y2109/00—Light sources with light-generating elements disposed on transparent or translucent supports or substrates
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L25/00—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof
- H01L25/03—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes
- H01L25/04—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers
- H01L25/075—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L33/00
- H01L25/0753—Assemblies consisting of a plurality of individual semiconductor or other solid state devices ; Multistep manufacturing processes thereof all the devices being of a type provided for in the same subgroup of groups H01L27/00 - H01L33/00, or in a single subclass of H10K, H10N, e.g. assemblies of rectifier diodes the devices not having separate containers the devices being of a type provided for in group H01L33/00 the devices being arranged next to each other
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L2924/00—Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
- H01L2924/0001—Technical content checked by a classifier
- H01L2924/0002—Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L33/00—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof
- H01L33/48—Semiconductor devices having potential barriers specially adapted for light emission; Processes or apparatus specially adapted for the manufacture or treatment thereof or of parts thereof; Details thereof characterised by the semiconductor body packages
- H01L33/58—Optical field-shaping elements
- H01L33/60—Reflective elements
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Theoretical Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Illuminated Signs And Luminous Advertising (AREA)
Abstract
A low-profile illuminator (6) comprises a transparent plate (1) carrying an array of rearward facing light sources (2) mounted on the rear of the plate (3), combined with an array of concave reflectors (4) located adjacent to the rear surface of the plate and arranged to collect light from the light sources and reflect the collected light back through the transparent plate. The illuminator may be used to back-illuminate a sign or display or it may be operated as a light source to illuminate objects at a distance. A feature of the design is that the beam from the illuminator may be narrowly convergent or broadly diverging dependent on the arrangement of the construction parameters.
Description
2360868 "Low-profile Illuminators" This invention relates to illuminators
and more particularly to low- profile illuminators.
It is notoriously difficult to create a large area illuminator which is simultaneously uniform, directional, of high brightness and low profile (le. shallow). Existing forms of illuminator may embody some, but not all, of these features. For example, a simple back-11luminated sign or display may be of low profile, but uniformity is normally achieved by an optically diffusing layer and the brightness is low. Another example would be the requirement to illuminate a small distant object with a welldirected beam of light, traditionally achieved by using a small highbrightness light source and a combination of lenses and/or mirrors. Such an arrangement fulfils the requirements but cannot be made low-profile.
It is an object of the present invention to provide a low-profile illuminator of uniform high brightness whose degree of directionality may be pre-detennined by varying the construction parameters.
Accordingly, one aspect of the present invention provides a low-profile compris' 5 ing: a transparent plate having a front and a rear surfaceone or more rearward facing light sources mounted on the rear surface of the plate; and one or more reflectors located adjacent to the rear surface of the 2 plate and arranged to collect light frorn the one or more light sources and reflect the collected light back through the transparent plate.
Preferably, the one or more light sources comprise light-emitting diodes (LED's).
Conveniently, the one or more light sources are carried on the transparent plate.
Advantageously, the one or more light sources are carried on the rear surface of the transparent plate.
Preferably, a light emitting surface of the or each light source faces the or each reflector.
Advantageously, the transparent plate carries a circuit associated with the one or more light sources.
Conveniently, the circuit comprises conductive material deposited onto a surface of the transparent plate.
Preferably, the conductive material comprises a selectively etched conductive coating or a screen-pi-inted conductive paste.
Advantageously, the conductive material is provided on a thin transparent organic film which is subsequently bonded to the transparent plate.
Conveniently, the transparent plate carries control circuitry associated with the one or more light sources.
Preferably, the control circuitry embodies one or more light-sensitive components to measure the ambient light level.
Advantageously, each light source is associated with a reflector.
Conveniently, each light source is located at or close to the focus of each reflector.
Preferably, each reflector is parabolic to provide a narrow beam or field of view.
Alternatively, each light source is located away from the focus of each reflector.
Conveniently, each reflector is spherical and shallow to provide a wide beam or field of view.
Advantageously, the illuminator is constructed from a plurality of separate illuminators.
Preferably, the illuminator is combined with a sign consisting of transparent and opaque areas to produce a backlit display unit.
Conveniently, the surface of the or each reflector is provided with fine dimples to provide a more uniform distribution of reflected light.
Advantageously, a diffusing member is provided on the front surface of the transparent plate.
4 Preferably, the one or more reflectors are laterally displaced with respect to the one or more light sources such that the combined light beam exits the transparent plate at an angle fi-om the perpendicular to the plane of the plate.
The or each reflector is preferably concave. Conveniently, the or each light source has an emitting surface facing the or each reflector.
In order that the present invention may be more readily understood, an embodiment thereof will now be described, by way of example, with reference to the accompanying drawing, Figure 1, which shows a partial cross-section through an illuminator embodying the present invention.
Referring to Figure 1, a low profile illuminator 6 comprises a transparent plate 1 fitted with a plurality of light emitting diodes (LED's) 2 which are arranged in an array on the rear surface 3 of the transparent plate and positioned such that the light produced by the LED's is directed away from the transparent plate. The transparent plate is also provided with a reflector bank consisting of a plurality of reflectors 4, wherein each reflective surface is spaced apart from the LED's 2. The bank of reflectors 4 is arranged such that the light emitted by the LED's 2 is reflected back towards and through the transparent plate 1. Generally, but not exclusively, each reflector 4 will be aligned symmetrically with an adjacent LED 2. The pi-eferred method of attaching the transparent plate to the reflector bank is by the use of a layer of potting compound. Each reflector 4 is preferably concave in section.
Tlic transparent plate 1I can be iiiaiiufactuied fi-om sheet glass or a suitable plastics material. A circuit 5 comprising a network of fine conductors is laid on, or within, the transparent plate 1 to provide electrical connections to the grid of LED's 2. The circuit 5 is connected to a power supply (not shown) by means of wires (not shown) attached to the circuit, preferably at the edge of the transparent plate 1. The wires may be attached to the circuit 5 by soldering, welding or by conductively epoxying the wires in contact with the circuit 5.
The circuit 5 may include a control circuit to define and control the current applied to the LED's 2 on the transparent plate 1. In a preferred embodiment the illuminator is fitted with one or more light sensitive components. The light sensitive components measure the ambient light and, in conjunction with the control circuit, vary the illumination provided by the LED's 2 in accordance with the ambient lighting conditions.
Some of the known means for producing a network of fine conductors on a substrate (i.e. manufacturing printed circuits or printed wiring) involve the selective etching of conductive coatings that have been deposited on the substrate. Other methods involve screen printing of metal/glass or metal/organic pastes onto the substrate. The screen printed substrate is then respectively fired, or cured, so that the defined circuit is set. The firing step could also have the benefit of toughening the glass if glass is used as the substrate.
The network of fine conductors may be deposited directly onto a surface of the transparent plate 1 although it is also possible to provide a network of fine conductors on a thin transparent organic film which can then be bonded to the transparent plate 1. The thin transparent film may be flexible or rigid.
6 It should also be appreciated that the fine network of conductors which forms part of the circuit 5 can be formed with much wider transparent conductors prepared using conventionally known techniques and processes.
The overall size of the illuminator 6, for example, can be anywhere between 10min and 2000mm along either of its edges. For large illuminators, the transparent plate 1 comprises a plurality of separate transparent plates each of which is manufactured as indicated above.
In a preferred embodiment, each illuminator 6 comprises a matrix of many reflectors 4 making up a reflector bank, each of the reflectors 4 having its own LED light source 2. When viewed from the front side of the transparent plate, the illummiator 6 appears as a solid block of light, and such a self-contained illuminating panel may be used as a backlight behind any transparent sign or display. Alternatively, the illuminator 6 may be used on its own as a light source.
The design of the reflector bank can be tailored to a specific application in which the illuminator 6 is to be used. The degree of directionality of the light emerging from the transparent plate is determined by the shape of the individual reflectors 4 in the reflector bank and by the separation between the reflectors 4 and the LED's 2. For example, if the light is to be highly directional, as would be required if the illuminator 6 is to be used as a backlight in a location where there is a high level of ambient lighting, or where a narrow beam of light is desired when the illuminator 6 is being used as a light source, then the reflectors 4 would be of parabolic form and the LED's 2 would be positioned at the foci of the parabolas. It should be understood that in this 7 configuration each LED and its associated reflector generates a narrow beam and that the directional beam from the illuminator 6 is composed of the overlapping individual beams from the plurality of LED/reflector elements.
Alternatively, if a wide viewing angle is required when the illuminator 6 is being used as a backlight, or a broad beam of light is desired when the illuminator 6 is being used as a light source, then the reflectors 4 may be manufactured with a shallow spherical form and the LED's 2 positioned closer to the reflectors than the foci of the reflectors. In the limit, when the radius of the shallow reflectors becomes infinite, the reflector bank degenerates into a plane mirror and in this configuration the maximum beam spread is obtained at the minimum brightness level.
When the above-described illuminator is configured as a backlight it may be placed behind a sign consisting of transparent and opaque areas, or it may form part of the sign such that the opaque areas are deposited on, or attached to, the transparent plate 1.
It may be appreciated that the operation of the illuminator is not confined to wavelengths in the visible region of the spectrum but may be constructed with infrared emitting LED's to provide an invisible source of radiation.
A refinement of the present invention is to provide fine dimples in the surface of the reflectors 4 so as to give a more uniform distribution of reflected light. An alternative method of creating a more uniform distribution of reflected light is to incorporate a diffuser on the front of the transparent plate which carries the array of LED's.
8 Another refinement of the present invention, when used as a backlight, is to provide control circuitry to selectively address pixels in the array of LED's such that words or moving images may be displayed.
A farther refinement of the present invention is to laterally displace the array of reflectors 4 with respect to the array of LED's 2 on the transparent plate 1, such that each LED is no longer on the centreline of its associated reflector. By this means it is possible to deflect the emerging beams from each LED/reflector element such that the combined beam exits the transparent plate at an angle to the perpendicular to the plate.
In the present specification "comprise" means 'ITicludes or consists of' and 11comprising" means "Including or consisting of'.
The features disclosed in the foregoing description, or the following claims, or the accompanying drawing, expressed in their specific forms or in terms of a means for performing the disclosed function, or a method or process for attaining the disclosed result, as appropriate, may, separately, or in any combination of such features, be utilised for realising the invention in diverse forms thereof.
Claims (21)
- 9 CLAIMSA low-profile illuminator comprising-. a transparent plate having a front and a rear surface; one or more rearward facing light sources mounted on the rear surface of the plate; and one or more reflectors located adjacent to the rear surface of the plate and arranged to collect light from the one or more light sources and reflect the collected light back through the transparent plate.
- 2. An illuminator according to claim 1, wherein the one or more light sources comprise light-emitting diodes (LED's).
- 3. An illuminator according to any preceding claim, wherein the transparent plate carries a circuit associated with the one or more light sources.
- 4. An illuminator according to clairn 3, wherein the circuit comprises conductive material deposited onto a surface of the transparent plate.
- 5. An illuminator according to claim 4, wherein the conductive material comprises a selectively etched conductive coating or a screen-printed conductive paste.
- 6. An illuminator according to any preceding claim wherein the conductive material is provided on a thin transparent organic film which is subsequently bonded to the transparent plate.
- 7. An illuminator according to any preceding claim, wherein the transparent plate carries control circuitry associated with the one or more light sources.
- 8. An illuminator according to claim 7, wherein the control circuitry embodies one or more light-sensitive components to measure the ambient light level.
- 9. An illuminator according to any preceding claim, wherein each light source is associated with a reflector.
- 10. An illuminator according to any preceding claim, wherein each light source is located at or close to the focus of each reflector.
- 11. An illuminator according to claim 10, wherein each reflector is parabolic to provide a narrow beam or field of view.
- 12. An illuminator according to any one of claims 1 to 9, wherein each light source is located away from the focus of each reflector.
- 13. An illuminator according to claim 10, wherein each reflector is spherical and shallow to provide a wide beam or field of view.
- 14. An illuminator according to any preceding claim, wherein the illuminator is constructed from a plurality of separate illuminators according to any preceding claim.
- 15. An illuminator according to any preceding claim, wherein the illuminator is combined with a sign consisting of transparent and opaque areas to produce a backlit display unit.11
- 16. An illuminator according to any preceding claim, wherein the surface of the or each reflector is provided with fine dimples to provide a more uniform distribution of reflected light.
- 17. An illuminator according to any preceding claim wherein a diffusing member is provided on the fi-ont surface of the transparent plate.
- 18. An illuminator according to any preceding claim, wherein the one or more reflectors are laterally displaced with respect to the one or more light sources such that the combined light beam exits the transparent plate at an angle from the perpendicular to the plane of the plate.
- 19. An illuminator according to any preceding claim, wherein the one or more reflectors are concave in section.
- 20. An illuminator substantially as hereinbefore described with reference to and as shown in the accompanying drawing.
- 21. Any novel feature or combination of features disclosed herein.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0007786A GB2360868A (en) | 2000-03-30 | 2000-03-30 | Low-profile Illuminators |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB0007786A GB2360868A (en) | 2000-03-30 | 2000-03-30 | Low-profile Illuminators |
Publications (3)
Publication Number | Publication Date |
---|---|
GB0007786D0 GB0007786D0 (en) | 2000-05-17 |
GB2360868A true GB2360868A (en) | 2001-10-03 |
GB2360868A8 GB2360868A8 (en) | 2001-10-17 |
Family
ID=9888804
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB0007786A Withdrawn GB2360868A (en) | 2000-03-30 | 2000-03-30 | Low-profile Illuminators |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB2360868A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008036640A1 (en) * | 2006-09-21 | 2008-03-27 | 3M Innovative Properties Company | Led backlight |
CN102980104A (en) * | 2012-11-30 | 2013-03-20 | 京东方科技集团股份有限公司 | Backlight module and display device utilizing same |
CN104006327A (en) * | 2013-02-27 | 2014-08-27 | 纬创资通股份有限公司 | Light-emitting diode backlight module |
EP2771798A4 (en) * | 2011-10-24 | 2015-07-29 | Mark Elliott | Display apparatus |
Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04159519A (en) * | 1990-10-24 | 1992-06-02 | Stanley Electric Co Ltd | Liquid crystal display device with led backlight and its manufacture |
-
2000
- 2000-03-30 GB GB0007786A patent/GB2360868A/en not_active Withdrawn
Patent Citations (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH04159519A (en) * | 1990-10-24 | 1992-06-02 | Stanley Electric Co Ltd | Liquid crystal display device with led backlight and its manufacture |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008036640A1 (en) * | 2006-09-21 | 2008-03-27 | 3M Innovative Properties Company | Led backlight |
US7481563B2 (en) | 2006-09-21 | 2009-01-27 | 3M Innovative Properties Company | LED backlight |
CN101517467B (en) * | 2006-09-21 | 2011-08-10 | 3M创新有限公司 | LED backlight |
EP2771798A4 (en) * | 2011-10-24 | 2015-07-29 | Mark Elliott | Display apparatus |
CN102980104A (en) * | 2012-11-30 | 2013-03-20 | 京东方科技集团股份有限公司 | Backlight module and display device utilizing same |
CN104006327A (en) * | 2013-02-27 | 2014-08-27 | 纬创资通股份有限公司 | Light-emitting diode backlight module |
EP2772938A1 (en) * | 2013-02-27 | 2014-09-03 | Wistron Corporation | Light emitting diode backlight module field of the invention |
Also Published As
Publication number | Publication date |
---|---|
GB0007786D0 (en) | 2000-05-17 |
GB2360868A8 (en) | 2001-10-17 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |