Illumination apparatus

• US 10,533,730 B2
• Filed: 05/01/2019
• Issued: 01/14/2020
• Est. Priority Date: 10/21/2010
• Status: Active Grant

• Current Assignee: Optovate Ltd. (Reald Spark, LLC)
• Original Assignee: Optovate Ltd. (Reald Spark, LLC)
• Inventors: Harrold, Jonathan, Woodgate, Graham J.
• Primary Examiner(s): Bowman, Mary Ellen
• Application Number:
  US16/400,223
• Publication Number:
  US 20190257497A1
• Time in Patent Office: 258 Days
• 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 for manufacturing an illumination apparatus, the method comprising:

filling a container with a liquid and diced LEDs;

providing a substrate within the container, the substrate having an array of adhesive regions interspersed by non-adhesive regions formed on a surface of the substrate; and

self-assembling, by the LEDs, onto the adhesive regions by means of adhesion between the LEDs and the adhesive regions.

2. The method according to claim 1, wherein the adhesive regions are electrically conductive.

3. The method according to claim 2, wherein the adhesive regions are solder regions.

4. The method according to claim 1, wherein the non-adhesive regions are resist regions.

5. The method according to claim 1, wherein each of the LEDs is coated to preferentially attach to an adhesive region in a particular orientation.

6. The method according to claim 5, wherein the particular orientation of each LED is:

an orientation in which a p-doped layer of the LED is facing away from the surface of the substrate;

or

an orientation in which an n-doped layer of the LED is facing away from the surface of the substrate.

7. The method according to claim 1, wherein the LEDs are Vertical Thin Film LEDs.

8. The method according to claim 1, further comprising:

determining an orientation of each of the self-assembled LEDs.

9. The method according to claim 8, wherein the orientation of each of the self-assembled LEDs is determined by inspection or electrical testing.

10. The method according to claim 1, further comprising arranging an optical element array in alignment with the LEDs.

11. The method according to claim 1, wherein the LEDs each have a maximum dimension of 0.1 mm or less.

12. The method of claim 1, wherein the LEDs self-assemble into a precision array.

13. The method of claim 1, further comprising providing a monolithic array of LEDs and dicing the array to provide the diced LEDs.

14. The method of claim 13, wherein the array is diced using a laser lift off process.