Surface illuminating apparatus

• US 5,079,675 A
• Filed: 11/08/1990
• Issued: 01/07/1992
• Est. Priority Date: 11/08/1990
• Status: Expired due to Fees

• Current Assignee: Optes, Inc. (ZEON Corporation)
• Original Assignee: Deilaito Co. Ltd.
• Inventors: Nakayama, Kouichi
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): LEE, Y MY QUACH
• Application Number:
  US07/610,869
• Time in Patent Office: 425 Days
• Field of Search: 362/26, 362/27, 362/29, 362/30, 362/31, 362/97, 362/244, 362/330, 362/331, 362/332
• US Class Current: 362/613
• CPC Class Codes: G02B 6/0038 Linear indentations or grooves, e.g. arc-shaped grooves or meandering grooves, extending over the full length or width of the light guide
• CPC Class Codes: G09F 13/0422 Reflectors
• CPC Class Codes: G09F 13/14 Arrangements of reflectors therein
• CPC Class Codes: G09F 2013/145 curved reflectors

Abstract

The present invention relates to a surface illuminating apparatus for illuminating an object or a space in a room or the like and an object of the invention is to provide a surface illuminating apparatus in which an illuminance can be increased and can be made uniform and a transparent plate can be made thin. The surface illuminating apparatus according to the invention comprises: at least one laminated flat plate-like transparent plate; a first reflecting unit arranged on one surface of the transparent plate; at least one light source arranged near side edge portions of the transparent plate; a second reflecting unit arranged around the light source; and a plurality of groove portions which are formed on the surface of the transparent plate on the side opposite to the first reflecting unit and each of which is constructed by two inclined surfaces, wherein inclination angles of the inclined surfaces of the groove portion on the side opposite to the light source to the transparent plate are set to values within a range such that the lights which enter from the light source into the transparent plate in parallel with the surface thereof are totally reflected by the inclined surfaces and the totally reflected lights are not totally reflected by the other surface of the transparent plate.

Claims

1. A surface illuminating apparatus comprising:

at least one flat plate-like transparent plate;

a first reflecting unit arranged on one surface of the transparent plate;

a light source arranged near one side edge portion of the transparent plate;

a second reflecting unit arranged around the light source; and

a plurality of groove portions which are formed on the surface of the transparent plate on the side of the first reflecting unit and each of which is constructed by two inclined surfaces,

wherein an inclination angle of the inclined surface of the groove portion on the side opposite to the light source to the surface of the transparent plate is set to a value within a range such that a light which enters from the light source into the transparent plate in parallel with the surface thereof is totally reflected by the inclined surface and the totally reflected light is not totally reflected by the other surface of the transparent plate, and an inclination angle of the inclined surface of the groove portion on the side which does not face the light source to the surface of the transparent plate is set to almost 90°

.

2. An apparatus according to claim 1, wherein the first reflecting unit is a reflecting plate.

3. An apparatus according to claim 1, wherein the second reflecting unit is a reflecting barrel.

4. A surface illuminating apparatus comprising:

at least one flat plate-like transparent plate;

a first reflecting unit arranged on one surface of the transparent plate;

light sources arranged near both side edge portions of the transparent plate;

second reflecting units arranged around the light sources; and

a plurality of groove portions which are formed on the surface of the transparent plate on the side of the first reflecting unit and each of which is constructed by two inclined surfaces,

wherein an inclination angle of the inclined surface of the groove portion on the side opposite to the light source to the surface of the transparent plate is set to a value within a range such that a light which enters from the near light source into the transparent plate in parallel with the surface thereof is totally reflected and the totally reflected light is not totally reflected by the other surface of the transparent plate, and an inclination angle of the inclined surface of the groove portion on the side opposite to the remote light source to the surface of the transparent plate is set to almost 90°

.

5. An apparatus according to claim 4, wherein the first reflecting unit is a reflecting plate.

6. An apparatus according to claim 4, wherein the second reflecting unit is a reflecting barrel.