Light source device, illumination device liquid crystal device and electronic apparatus

• US 20020048163A1
• Filed: 07/12/2001
• Published: 04/25/2002
• Est. Priority Date: 07/13/2000
• Status: Active Grant

• Current Assignee: BOE Technology Group Co., Ltd.
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Kawakami, Hisanori, Endo, Kogo
• Granted Patent: US 6,883,934 B2
• Time in Patent Office: Days
• US Class Current: 362/31
• CPC Class Codes: G02B 6/0016 Grooves, prisms, gratings, scattering particles or rough surfaces
• CPC Class Codes: G02B 6/003 Lens or lenticular sheet or layer
• CPC Class Codes: G02B 6/0051 Diffusing sheet or layer
• CPC Class Codes: G02F 1/133615 Edge-illuminating devices, i.e. illuminating from the side

Abstract

A light source device 41A, 41B or 41C comprising a lens 44A, 44B or 44C which receives light from a light emitting device 43 such as LED. The lens 44A is a lens having the property that the directivity of exiting light in the Y direction is higher than the directivity in the X direction perpendicular to the Y direction. Namely, the light emitted from the light emitting device 43 is condensed in a narrow angular range in the Y direction, and is scattered in a wide angular range in the X direction. When the light source device 41A is used as a light source of an illumination device of a liquid crystal device, the height direction of a light guide in which the dimension is small coincides with the Y direction, and the width direction of the light guide in which the dimension is large coincides with the X direction.

Claims

1. A light source device comprising:

a light emitting device; and

a lens which receives the light emitted from the light emitting device, wherein the lens is a lens having a property that directivity of exiting light in one direction is higher than directivity of exiting light in a direction perpendicular to the one direction.

3. The light source device according to claim 1, wherein the lens has any one of a semicircular pillar shape, a prismatic shape, or a partial circular pillar shape having a Fresnel lens surface.

2. A light source device comprising:

a light emitting device; and

a lens which receives the light emitted from the light emitting device, wherein the lens has a planar light incidence plane and a non-planar light exiting plane having a shape in which a height from the light incidence plane changes in one direction, while a height from the light incidence plane is constant in a direction perpendicular to the one direction.

13. The light source device according to claim 2, wherein the lens has any one of a semicircular pillar shape, a prismatic shape, or a partial circular pillar shape having a Fresnel lens surface.

4. An illumination device comprising:

a light source device which emits light; and

a light guide which receives light from the light source device by a light receiving plane and causes light to exit from a light exiting plane;

wherein the light source device comprises a light emitting device and a lens which receives the light emitted from the light emitting device;

wherein the lens is a lens having a property that directivity of exiting light in one direction is higher than directivity of exiting light in a direction perpendicular to the one direction, the one direction in which the exiting light has higher directivity being set to a height direction of the light guide, and the perpendicular direction in which the exiting light has lower directivity being set to a width direction of the light guide.

6. The illumination source devices according to claim 4, wherein the lens has any one of a semicircular pillar shape, a prismatic shape, or a partial circular pillar shape having a Fresnel lens surface.

7. The illumination device according to claim 4, wherein the lens is provided on the light receiving plane of the light guide, for condensing light.

5. An illumination device comprising:

a light source device which emits light; and

a light guide which receives light from the light source device by a light receiving plane and causes light to exit from a light exiting plane;

wherein the light source device comprises a light emitting device, and a lens which receives the light emitted from the light emitting device;

wherein the lens has a planar light incidence plane and a non-planar light exiting plane having a shape in which a height from the light incidence plane changes in one direction, while a height is constant in a direction perpendicular to the one direction, the one direction being set to a height direction of the light guide, and the perpendicular direction being set to a width direction of the light guide.

14. The illumination source devices according to claim 5, wherein the lens has any one of a semicircular pillar shape, a prismatic shape, or a partial circular pillar shape having a Fresnel lens surface.

15. The illumination device according to claim 5, wherein the lens is provided on the light receiving plane of the light guide, for condensing light.

8. A liquid crystal device comprising:

a liquid crystal panel comprising a liquid crystal held between a pair of substrates; and

an illumination device for supplying light to the liquid crystal panel;

wherein the illumination device comprises a light source device which emits light, and a light guide which receives light from the light source device by a light receiving plane and causes light to exit from a light exiting plane; and

the light source device comprises a light emitting device and a lens which receives the light emitted from the light emitting device;

wherein the lens is a lens having a property that directivity of exiting light in one direction is higher than directivity of exiting light in a direction perpendicular to the one direction, the one direction in which the exiting light has higher directivity being set to a height direction of the light guide, and the perpendicular direction in which the exiting light has lower directivity being set to a width direction of the light guide.

10. The liquid crystal device according to claim 8, wherein the lens has any one of a semicircular pillar shape, a prismatic shape, or a partial circular pillar shape having a Fresnel lens surface.

11. The liquid crystal device according to claim 8, wherein the lens is provided on the light receiving plane of the light guide, for condensing light.

12. An electronic apparatus comprising a liquid crystal device, and a control circuit for controlling operation of the liquid crystal device, wherein the liquid crystal device comprises a liquid crystal device according claim 8.

9. A liquid crystal device comprising:

a liquid crystal panel comprising a liquid crystal held between a pair of substrates; and

an illumination device for supplying light to the liquid crystal panel;

wherein the illumination device comprises a light source device which emits light, and a light guide which receives light from the light source device by a light receiving plane and causes light to exit from a light exiting plane; and

the light source device comprises a light emitting device, and a lens which receives the light emitted from the light emitting device;

wherein the lens has a planar light incidence plane and a non-planar light exiting plane having a shape in which a height from the light incidence plane changes in one direction, while a height is constant in a direction perpendicular to the one direction, the one direction being set to a height direction of the light guide, and the perpendicular direction being set to a width direction of the light guide.

16. The liquid crystal device according to claim 9, wherein the lens has any one of a semicircular pillar shape, a prismatic shape, or a partial circular pillar shape having a Fresnel lens surface.

17. The liquid crystal device according to claim 9, wherein the lens is provided on the light receiving plane of the light guide, for condensing light.

18. An electronic apparatus comprising a liquid crystal device, and a control circuit for controlling operation of the liquid crystal device, wherein the liquid crystal device comprises a liquid crystal device according claim 9.