Planar illumination device

• US 6,530,670 B2
• Filed: 10/29/2001
• Issued: 03/11/2003
• Est. Priority Date: 11/06/2000
• Status: Expired due to Term

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.)
• Inventors: Hirayama, Yoshinobu
• Primary Examiner(s): O'Shea, Sandra
• Assistant Examiner(s): Amarantides, John
• Application Number:
  US09/984,305
• Publication Number:
  US 20020054489A1
• Time in Patent Office: 498 Days
• Field of Search: 362/31, 362/235, 362/323, 362/341, 362/26, 362/27, 385/146, 349/65
• US Class Current: 362/628
• CPC Class Codes: G02B 6/0021 for housing at least a part of the light source, e.g. by forming holes or recesses
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• CPC Class Codes: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide

Abstract

A planar illumination device has a light source that shines light into a light guide plate through one side face (i) thereof and a reflector member laid on the back face of the light guide plate opposite to the light emission face thereof. In the vicinity of another side face (ii) of the light guide plate opposite to the side face (i) thereof through which the light is shone into the light guide plate, a slit is formed so as to extend along that side face (ii). A portion of the reflector member is, by being bent into an L shape, formed into an insertion portion, and this insertion portion is inserted into the slit.

Claims

1. A planar illumination device comprising a light source that shines light into a light guide plate through at least one side face (i) thereof and a reflector member laid on a back face of the light guide plate opposite to a light emission face thereof,

wherein, in vicinity of at least one another side face (ii) of the light guide plate other than the one side face (i) thereof through which the light is shone into the light guide plate, a slit is formed so as to extend parallel along said at least one another side face (ii), and a portion of the reflector member is, by being bent into an L shape, formed into an insertion portion so that this insertion portion is inserted into the slit.

2. A planar illumination device as claimed in claim 1,

wherein the reflector member has intermittent grooves formed therein to ease the bending of the insertion portion.

3. A planar illumination device comprising a light source that shines light into a light guide plate through one side face (i) thereof and a reflector member laid on a back face of the light guide plate opposite to a light emission face thereof,

wherein, in vicinity of another side face (ii) of the light guide plate opposite to the one side face (i) thereof through which the light is shone into the light guide plate, a slit is formed so as to extend parallel along said another side face (ii), and a portion of the reflector member is, by being bent into an L shape, formed into an insertion portion so that this insertion portion is inserted into the slit.

4. A planar illumination device as claimed in claim 3,

wherein the reflector member has intermittent grooves formed therein to ease the bending of the insertion portion.

5. A planar illumination device as claimed in claim 3,

wherein the light guide plate is shaped like a wedge so as to have decreasing thicknesses from the side face (i) to the side face (ii) thereof.