Image display device and light emission device

• US 20060274227A1
• Filed: 08/16/2006
• Published: 12/07/2006
• Est. Priority Date: 05/16/1997
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Ishikawa, Masayuki, Konno, Kuniaki, Umeji, Tadashi, Komoto, Satoshi, Okazaki, Haruhiko, Nitta, Koichi
• Granted Patent: US 7,583,019 B2
• Time in Patent Office: Days
• US Class Current: 349/71
• CPC Class Codes: G02B 6/0023 provided by one optical element, or plurality thereof, placed between the light guide and the light source, or around the light source
• CPC Class Codes: G02B 6/0025 Diffusing sheet or layer; Prismatic sheet or layer
• CPC Class Codes: G02B 6/003 Lens or lenticular sheet or layer
• CPC Class Codes: G02B 6/0035 provided on the surface of the light guide or in the bulk of it
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02B 6/0055 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0068 Arrangements of plural sources, e.g. multi-colour light sources
• CPC Class Codes: G02B 6/0073 Light emitting diode [LED]
• CPC Class Codes: G02F 1/1334 based on polymer dispersed liquid crystals, e.g. microencapsulated liquid crystals
• CPC Class Codes: G02F 1/133603 with LEDs
• CPC Class Codes: G02F 1/133605 including specially adapted reflectors
• CPC Class Codes: G02F 1/133613 characterized by the sequence of light sources
• CPC Class Codes: G02F 1/133614 using photoluminescence, e.g. phosphors illuminated by UV or blue light
• CPC Class Codes: G02F 1/133617 Illumination with ultraviolet light; Luminescent elements or materials associated to the cell
• CPC Class Codes: G02F 1/13725 based on guest-host interaction G02F1/13762, G02F1/13737, take precedence
• CPC Class Codes: G02F 2203/34 Colour display without the use of colour mosaic filters
• CPC Class Codes: H01L 2224/48091 Arched
• CPC Class Codes: H01L 2224/48247 connecting the wire to a bond pad of the item
• CPC Class Codes: H01L 2224/48257 connecting the wire to a die pad of the item
• CPC Class Codes: H01L 2224/48465 : the other connecting portion not on the bonding area being a wedge bond, i.e. ball-to-wedge, regular stitch
• CPC Class Codes: H01L 2224/49107 : on the semiconductor or solid-state body
• CPC Class Codes: H01L 2224/49113 : the connectors connecting different bonding areas on the semiconductor or solid-state body to a common bonding area outside the body, e.g. converging wires
• CPC Class Codes: H01L 2224/8592 : Applying permanent coating, e.g. protective coating
• CPC Class Codes: H01L 25/0753 : the devices being arranged next to each other
• CPC Class Codes: H01L 25/0756 : Stacked arrangements of devices
• 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 2924/00012 : Relevant to the scope of the group, the symbol of which is combined with the symbol of this group
• CPC Class Codes: H01L 2924/00014 : the subject-matter covered by the group, the symbol of which is combined with the symbol of this group, being disclosed without further technical details
• CPC Class Codes: H01L 2924/181 : Encapsulation
• CPC Class Codes: H01L 2924/3025 : Electromagnetic shielding
• CPC Class Codes: H01L 33/50 : Wavelength conversion elements
• CPC Class Codes: H01L 33/505 : characterised by the shape, e.g. plate or foil
• 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: H04N 9/315 : Modulator illumination systems general applications of lighting devices F21V; general optical systems G02B; lamp houses for projectors not peculiar to the presence of an electronic spatial light modulator G03B21/20

Abstract

An image display device including a light emission section which emits light to an intensity adjusting section and a wavelength conversion section which change the intensity and wavelength of the emitted light. Phosphors and phosphor like materials are employed in wavelength conversion and a liquid crystal is employed for the light adjustment. The light emission device may include plural semiconductor light emitting elements having a different wavelength ranges such as diodes stacked in a compact and predetermined order such that wavelengths of light from each diode are emitted from the light emitting elements.

Claims

1. A semiconductor light emitting device, comprising:

a light emitting element having a first electrode and a second electrode, which are provided on a first side of the light emitting element, and

a wavelength change material provided on a second side of the light emitting element, the second side of the light emitting element being opposite to the first side of the light emitting element.

2. A semiconductor light emitting device of claim 1, wherein the light emitted from the light emitting element is extracted toward a direction which is from the first side to second side of the light emitting element.

3. A semiconductor light emitting device of claim 1, wherein the wavelength change material has substantially uniform thickness.

4. A semiconductor light emitting device of claim 1, wherein the wavelength change material is configured to absorb a light emitted from the light emitting element and to emit a light which has longer wavelength than the light emitted from the light emitting element.

5. A semiconductor light emitting device of claim 4, wherein the light emitted from the wavelength change material is extracted toward a direction which is from the first side to second side of the light emitting element.

6. A semiconductor light emitting device of claim 1, wherein the light emitting element is configured to emit blue light.

7. A semiconductor light emitting device of claim 1, wherein the light emitting element is configured to emit ultraviolet light.

8. A semiconductor light emitting device of claim 5, wherein the wavelength change material has substantially uniform thickness.

9. A semiconductor light emitting device of claim 4, wherein the light emitted from the light emitting element is extracted toward a direction which is from the first side to second side of the light emitting element.

10. A semiconductor light emitting device of claim 9, wherein the light emitted from the wavelength change material is extracted toward a direction which is from the first side to second side of the light emitting element.

11. A semiconductor light emitting device of claim 1, wherein a wavelength change material is not provided on the first side of the light emitting element.

12. A semiconductor light emitting device of claim 11, wherein the light emitted from the light emitting element is extracted toward a direction which is from the first side to second side of the light emitting element.

13. A semiconductor light emitting device of claim 11, wherein the wavelength change material has substantially uniform thickness.

14. A semiconductor light emitting device of claim 11, wherein the wavelength change material is configured to absorb a light emitted from the light emitting element and to emit a light which has longer wavelength than the light emitted from the light emitting element.

15. A semiconductor light emitting device of claim 4, wherein the light emitted from the wavelength change material is extracted toward a direction which is from the first side to second side of the light emitting element.

16. A semiconductor light emitting device of claim 11, wherein the light emitting element is configured to emit blue light.

17. A semiconductor light emitting device of claim 11, wherein the light emitting element is configured to emit ultraviolet light.

18. A semiconductor light emitting device of claim 15, wherein the wavelength change material has substantially uniform thickness.

19. A semiconductor light emitting device of claim 14, wherein the light emitted from the light emitting element is extracted toward the direction which is from the first side to second side of the light emitting element.

20. A semiconductor light emitting device of claim 19, wherein the light emitted from the wavelength change material is extracted toward a direction which is from the first side to second side of the light emitting element.