IP Library Patent Application 12923481
Patent Application
App. No. 12/923,481

Display device and planar light source device

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Quick Facts
Patent No.
US None
App. No.
12/923,481
Abstract

The present invention relates to a technique which can make a backlight used in a liquid crystal display device thin and light-weighted. The present invention provides a liquid crystal display device which includes a display panel and a backlight which is arranged behind the display panel, wherein the backlight includes a film-like light guide member, a film-like light semi-transmissive member which is adhered to a first surface of the light guide member which faces the display panel in an opposed manner, a film-like reflective member which is adhered to a back surface of the light guide member opposite to the first surface, and a spot light source which is arranged at a position of the light guide member at which light is incident on the light guide member from the first surface or the back surface, and a refractive index of the light semi-transmissive member is set smaller than a refractive index of the light guide member.

Claims (19)

1 . A display device comprising:

a display panel: and

a backlight which is arranged behind the display panel, wherein

the display panel adheres a polarizer to a surface thereof which faces the backlight in an opposed manner and a back surface thereof opposite to the surface, and

the backlight includes a film-like light guide member, a film-like light polarization reflective member which is adhered to a first surface of the light guide member which faces the display panel in an opposed manner, a film-like reflective member which is adhered to a back surface of the light guide member opposite to the first surface, and a spot light source which is arranged at a position of the light guide member at which light is incident on the light guide member from the first surface or the back surface, wherein

a transmission axis of the polarization reflective member is arranged in the same direction as a transmission axis of the polarizer which is adhered to the surface of the display panel which faces the backlight in an opposed manner.

2 . A display device according to claim 1 , wherein the backlight includes a reflector which is arranged in the direction that the spot light source radiates the light in the film surface direction of the light guide member, and allows the light radiated from the spot light source to be incident on the light guide member by reflecting the light.

3 . A display device according to claim 1 , wherein the light semi-transmissive member or the polarization reflective member changes a ratio of transmissivity and reflectance of light which propagates in the light guide member corresponding to a distance from a position at which the light of the light guide member is incident.

4 . A display device according to claim 1 , wherein a plurality of through holes are formed in a plurality of portions of the light semi-transmissive member or the polarization reflective member, and the distribution density of the through holes is changed corresponding to a distance from a position at which the light of the light guide member is incident.

5 . A display device according to claim 1 , wherein the reflective member changes reflectance thereof corresponding to a distance from a position at which the light of the light guide member is incident.

6 . A display device according to claim 1 , wherein the reflective member has an irregular reflection pattern formed of a concave shape or a convex shape at a plurality of portions of a surface of the reflective member which is brought into close contact with the light guide member, and the distribution density of the irregular reflection pattern is changed corresponding to a distance from a position at which light of the light guide member is incident.

7 . A planar light source device comprising:

a light source; and

a film-like light guide member, wherein

the light source includes a film-like incident-light adjusting member which is arranged in the direction at which light is radiated in the direction perpendicular to a film surface of the light guide member, and changes the incident direction of light to the light guide member is changed in the propagation direction of light in the light guide member between a region on which the light is incident and a surface to which light of the light source is radiated, and

the incident-light adjusting member has one, two or more projections on a surface side which faces the light guide member in an opposed manner, and distal end surfaces of the projections are brought into close contact with the light guide member.

8 . A planar light source device according to claim 7 , wherein a radiation-light adjusting member which adjusts a radiation angle of the light from the radiation surface is provided to a radiation surface of the light of the light guide member.

9 . A planar light source device according to claim 8 , wherein a reflective member is provided to a back surface of the light guide member opposite to a surface on which the incident-light adjusting member is arranged and to a region which is overlapped to the incident-light adjusting member.

10 . A planar light source device according to claim 8 , wherein a projection of the incident-light adjusting member is a columnar projection having a curved bottom surface.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Sep 23, 2010
From: KURIHARA, HIROSHI
To: HITACHI DISPLAYS, LTD.
Reel/Frame 025075/0410 →