Illumination apparatus

• US 10,330,283 B2
• Filed: 12/16/2016
• Issued: 06/25/2019
• Est. Priority Date: 10/21/2010
• Status: Active Grant

• Current Assignee: Optovate Ltd. (Reald Spark, LLC)
• Original Assignee: Optovate Ltd. (Reald Spark, LLC)
• Inventors: Woodgate, Graham John, Harrold, Jonathan
• Primary Examiner(s): Bowman, Mary Ellen
• Application Number:
  US15/382,084
• Publication Number:
  US 20170102127A1
• Time in Patent Office: 921 Days
• Field of Search: 362236, 362245, 362253, 362299, 362300
• CPC Class Codes: F21K 9/00 Light sources using semiconductor devices as light-generating elements, e.g. using light-emitting diodes [LED] or lasers
• CPC Class Codes: F21K 9/64 using wavelength conversion means distinct or spaced from the light-generating element, e.g. a remote phosphor layer
• CPC Class Codes: F21K 9/68 Details of reflectors forming part of the light source
• CPC Class Codes: F21K 9/69 Details of refractors forming part of the light source
• CPC Class Codes: F21K 9/90 Methods of manufacture
• CPC Class Codes: F21V 13/04 the elements being reflectors and refractors for vehicle rear lights F21S43/40
• CPC Class Codes: F21V 17/00 Fastening of component parts of lighting devices, e.g. shades, globes, refractors, reflectors, filters, screens, grids or protective cages of light sources or light holders F21V19/00
• CPC Class Codes: F21V 23/002 Arrangements of cables or conductors inside a lighting device, e.g. means for guiding along parts of the housing or in a pivoting arm
• CPC Class Codes: F21V 5/007 Array of lenses or refractors for a cluster of light sources, e.g. for arrangement of multiple light sources in one plane combination of two or more refractors F21V5/008
• CPC Class Codes: F21V 9/30 Elements containing photoluminescent material distinct from or spaced from the light source shades F21V1/17; globes, bowls or cover glasses F21V3/08, F21V3/12; refractors F21V5/10; reflectors F21V7/26, F21V7/30; elements with provision for controlling the spectral properties or intensity F21V9/40
• CPC Class Codes: F21Y 2101/00 Point-like light sources
• CPC Class Codes: F21Y 2113/13 comprising an assembly of point-like light sources
• CPC Class Codes: F21Y 2115/10 Light-emitting diodes [LED]
• CPC Class Codes: G02B 19/0028 refractive and reflective surfaces, e.g. non-imaging catadioptric systems
• CPC Class Codes: G02B 19/0066 in the form of an LED array
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133607 the light controlling member including light directing or refracting elements, e.g. prisms or lenses
• CPC Class Codes: G02F 1/133612 Electrical details
• CPC Class Codes: G09G 3/2088 with use of a plurality of processors, each processor controlling a number of individual elements of the matrix
• CPC Class Codes: H01L 21/268 : using electromagnetic radiation, e.g. laser radiation
• CPC Class Codes: H01L 22/20 : Sequence of activities consisting of a plurality of measurements, corrections, marking or sorting steps
• CPC Class Codes: H01L 2224/16225 : the item being non-metallic, e.g. insulating substrate with or without metallisation
• CPC Class Codes: H01L 2224/73265 : Layer and wire connectors
• CPC Class Codes: H01L 24/32 : of an individual layer connector
• CPC Class Codes: H01L 25/0753 : the devices being arranged next to each other
• CPC Class Codes: H01L 25/167 : comprising optoelectronic devices, e.g. LED, photodiodes
• CPC Class Codes: H01L 2924/00 : Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/01322 : Eutectic Alloys, i.e. obtained by a liquid transforming into two solid phases
• CPC Class Codes: H01L 2924/09701 : Low temperature co-fired ceramic [LTCC]
• CPC Class Codes: H01L 2924/12035 : Zener diode
• CPC Class Codes: H01L 2924/12042 : LASER
• CPC Class Codes: H01L 2924/1301 : Thyristor
• CPC Class Codes: H01L 2924/13033 : TRIAC - Triode for Alternating Current - A bidirectional switching device containing two thyristor structures with common gate contact
• CPC Class Codes: H01L 2924/14 : Integrated circuits
• CPC Class Codes: H01L 2924/15787 : Ceramics, e.g. crystalline carbides, nitrides or oxides
• CPC Class Codes: H01L 2924/15788 : Glasses, e.g. amorphous oxides, nitrides or fluorides
• CPC Class Codes: H01L 2924/3512 : Cracking
• CPC Class Codes: H01L 2933/0033 : relating to semiconductor body packages
• CPC Class Codes: H01L 2933/0041 : relating to wavelength conversion elements
• CPC Class Codes: H01L 2933/005 : relating to encapsulations
• CPC Class Codes: H01L 2933/0058 : relating to optical field-shaping elements
• CPC Class Codes: H01L 2933/0066 : relating to arrangements for conducting electric current to or from the semiconductor body
• CPC Class Codes: H01L 33/0093 : Wafer bonding; Removal of the growth substrate
• CPC Class Codes: H01L 33/0095 : Post-treatment of devices, e.g. annealing, recrystallisation or short-circuit elimination
• CPC Class Codes: H01L 33/08 : with a plurality of light emitting regions, e.g. laterally discontinuous light emitting layer or photoluminescent region integrated within the semiconductor body H01L27/15 takes precedence
• CPC Class Codes: H01L 33/504 : Elements with two or more wavelength conversion materials
• CPC Class Codes: H01L 33/507 : the elements being in intimate contact with parts other than the semiconductor body or integrated with parts other than the semiconductor body
• CPC Class Codes: H01L 33/56 : Materials, e.g. epoxy or silicone resin
• CPC Class Codes: H01L 33/58 : Optical field-shaping elements
• CPC Class Codes: H01L 33/60 : Reflective elements
• CPC Class Codes: H01L 33/62 : Arrangements for conducting electric current to or from the semiconductor body, e.g. lead-frames, wire-bonds or solder balls
• CPC Class Codes: Y10T 29/49117 : Conductor or circuit manufacturing

Abstract

An illumination apparatus comprises a plurality of LEDs aligned to an array of directional optical elements wherein the LEDs are substantially at the input aperture of respective optical elements. An electrode array is formed on the array of optical elements to provide at least a first electrical connection to the array of LED elements. Advantageously such an arrangement provides low cost and high efficiency from the directional LED array.

Claims

1. A method of manufacturing an illumination apparatus, the method comprising:

forming a non-monolithic array of a plurality of light emitting elements on a support substrate;

measuring a combined spectral output for at least some of a first sub-plurality of the plurality of light emitting elements in a first region of the support substrate;

aligning a first wavelength conversion layer with the first sub-plurality of the plurality of light emitting elements of the first region, the first wavelength conversion layer having a first spectral characteristic based on the measured combined spectral output from the at least some of the first sub-plurality of the plurality of light emitting elements of the first region;

measuring a combined spectral output for at least some of a second sub-plurality of the plurality of light emitting elements in a second region of the support substrate; and

aligning at least a second wavelength conversion layer with the second sub-plurality of the plurality of light emitting elements of the second region, the second wavelength conversion layer having a second spectral characteristic based on the measured combined spectral output from the at least some of the second sub-plurality of the plurality of light emitting elements of the second region.

2. The method according to claim 1, wherein:

the aligning of the first wavelength conversion layer with the first sub-plurality of the plurality of light emitting elements of the first region provides a first region average white point;

the aligning of the second wavelength conversion layer with the second sub-plurality of the plurality of light emitting elements of the second region provides a second region average white point; and

the first region average white point and the second region average white point are substantially the same.

3. The method according to claim 1, wherein the first spectral characteristic of the first wavelength conversion layer is different than the second spectral characteristic of the second wavelength conversion layer.

4. The method according to claim 1, the method further comprising:

selecting a thickness of the first wavelength conversion layer based on the measured combined spectral output from the at least some of the first sub-plurality of the plurality of light emitting elements of the first region; and

selecting a thickness of the second wavelength conversion layer based on the measured combined spectral output from the at least some of the second sub-plurality of the plurality of light emitting elements of the second region.

5. The method according to claim 4, further comprising:

varying a solvent fraction of each of the first wavelength conversion layer and the second wavelength conversion layer to obtain the selected different thicknesses of the respective first wavelength conversion layer and the second wavelength conversion layer.

6. The method according to claim 1, wherein the illumination apparatus is for display illumination.

7. The method according to claim 1, wherein the illumination apparatus is a display.

8. The method according to claim 1, wherein the plurality of light emitting elements have a maximum dimension of 0.1 mm or less.

9. The method according to claim 1, wherein the first wavelength conversion layer and the second wavelength conversion layer are each aligned prior to a dicing of the substrate and a singulation of the plurality of light emitting elements in the first region and the second region.

10. A method of manufacturing an illumination apparatus, the method comprising:

forming a non-monolithic array of a plurality of light-emitting elements on a support substrate;

measuring a combined spectral output for at least some of a first sub-plurality of the plurality of light emitting elements in a first region of the support substrate;

aligning a first wavelength conversion layer with at least some of the first sub-plurality of the plurality of light emitting elements of the first region, the first wavelength conversion layer having a first spectral characteristic based on the measured combined spectral output from the at least some of the first sub-plurality of the plurality of light emitting elements of the first region;

measuring a combined spectral output for at least some of a second sub-plurality of the plurality of light emitting elements in a second region of the support substrate; and

aligning at least a second wavelength conversion layer with at least some of the second sub-plurality of the plurality of light emitting elements of the second region,

wherein the number of the second sub-plurality of the plurality of light emitting elements of the second region that are aligned with the second wavelength conversion layer is adjusted based on the measured combined spectral output from the at least some of the second sub-plurality of the plurality of light emitting elements of the second region.

11. An illumination apparatus, comprising:

a non-monolithic array of a plurality of light-emitting elements on a support substrate;

a first wavelength conversion layer in alignment with a first sub-plurality of the plurality of light emitting elements associated with a first region of the support substrate, the first wavelength conversion layer having a first spectral characteristic based on a measured combined spectral output from at least some of the first sub-plurality of the plurality of light emitting elements of the first region; and

at least a second wavelength conversion layer in alignment with at least some of a second sub-plurality of the plurality of light emitting elements associated with a second region of the support substrate, the second wavelength conversion layer having a second spectral characteristic based on a measured combined spectral output from at least some of the second sub-plurality of the plurality of light emitting elements of the second region.

12. The apparatus according to claim 11, wherein the plurality of light emitting elements have a maximum dimension of 0.1 mm or less.

13. The apparatus according to claim 11, wherein the apparatus is for display illumination.

14. The apparatus according to claim 11, wherein the apparatus is a display.

15. The apparatus according to claim 11, further comprising catadioptric optical elements.

16. The apparatus according to claim 15, wherein the catadioptric optical elements cooperate with the array of the plurality of light emitting elements to provide directional illumination of a display with cone angle below 30 degrees.

17. The apparatus according to claim 11, wherein the thickness of the first wavelength conversion layer is different than the thickness of the second wavelength conversion layer.

18. The apparatus according to claim 11, wherein the first wavelength conversion layer and the second wavelength conversion layer are each aligned prior to a dicing of the substrate and a singulation of the plurality of light emitting elements of the first region and the second region.

19. The apparatus according to claim 11, wherein the number of the second sub-plurality of the plurality of light emitting elements associated with the second region that are aligned with the second wavelength conversion layer is based on the measured combined spectral output from the at least some of the second sub-plurality of the plurality of light emitting elements associated with the second region.

20. The apparatus according to claim 11, wherein the first spectral characteristic of the first wavelength conversion layer is different than the second spectral characteristic of the second wavelength conversion layer, the first spectral characteristic is based on a first region average white point for the first region and the second spectral characteristic is based on a second region average white point for the second region.