Backlight device and liquid crystal display

Abstract

A backlight device includes a housing, a light source, a diffuse plate and a fixing member. The housing has an open surface. The light source is arranged in the housing. The diffuser plate is arranged on the open surface of the housing and allows light emitted from the light source to pass therethrough while diffusing the light. The fixing member prevents the diffuser plate from bending in a direction in which light passes through the diffuser plate. A part of the fixing member has transmittance adjusted to substantially equalize luminance distribution of light passed through the diffuser plate.

1 . A backlight device comprising:
 a housing that has an open surface;   a light source that is arranged in the housing;   a diffuser plate that is arranged on the open surface of the housing and allows light emitted from the light source to pass therethrough while diffusing the light; and   a bending prevention member that prevents the diffuser plate from bending in a direction in which light passes through the diffuser plate, wherein a part of the bending prevention member has transmittance adjusted to substantially equalize luminance distribution of light passed through the diffuser plate.   
   
   
       2 . The backlight device according to  claim 1 , wherein one end portion of the bending prevention member is engaged to a transparent hole formed on the diffuser plate. 
   
   
       3 . The backlight device according to  claim 2 , wherein the one end portion of the banding prevention member is made of material with transmittance equal to or lower than one of the diffuser plate. 
   
   
       4 . A backlight device comprising:
 a housing that has an open surface;   a light source that is arranged in the housing;   a diffuser plate that is arranged on the open surface of the housing, has a recessed portion on a surface of a light source side and allows light emitted from the light source to pass therethrough while diffusing the light; and   a supporting member that has one end portion engaged to the recessed portion of the diffuser plate and the other end portion engaged to the housing.   
   
   
       5 . The backlight device according to  claim 4 , wherein a part of the supporting member is made of light transmissive member in a region other than regions where the supporting member is engaged to the diffuser plate and the housing. 
   
   
       6 . The backlight device according to  claim 4 , wherein an optical characteristic agent is filled in clearance between the supporting member and the diffuser plate in a region where the supporting member is engaged to the diffuser plate. 
   
   
       7 . The backlight device according to  claim 4 , wherein a width of cross-sectional shape in the recessed portion of the diffuser plate is narrow in a region where light enters the diffuser plate. 
   
   
       8 . The backlight device according to  claim 4 , wherein the light source is a line light source,
 the supporting member extends in a direction which intersects with the light source and is mounted at the light source side of the diffuser plate, and   a protruding length of the supporting member from the diffuser plate is relatively small in a region adjacent to the light source and relatively large in a region away from the light source.   
   
   
       9 . A liquid crystal display comprising:
 a backlight device comprising:
 a housing that has an open surface; 
 a light source that is arranged in the housing; 
 a diffuser plate that is arranged on the open surface of the housing and allows light emitted from the light source to pass therethrough while diffusing the light; and 
 a bending prevention member that prevents the diffuser plate from bending in a direction in which light passes through the diffuser plate, wherein a part of the bending prevention member has transmittance adjusted to substantially equalize luminance distribution of light passed through the diffuser plate; 
   an optical sheet that is arranged in a position where light emitted from the light source has passed through the diffuser plate; and   a liquid crystal panel that is arranged in a position where light has passed through the optical sheet.   
   
   
       10 . A liquid crystal display comprising:
 a backlight device comprising:
 a housing that has an open surface; 
 a light source that is arranged in the housing; 
 a diffuser plate that is arranged on the open surface of the housing, has a recessed portion on a surface of a light source side and allows light emitted from the light source to pass therethrough while diffusing the light; and 
 a supporting member that has one end portion engaged to the recessed portion of the diffuser plate and the other end portion engaged to the housing.