Illumination light transmitting device

• US 4,918,577 A
• Filed: 09/15/1988
• Issued: 04/17/1990
• Est. Priority Date: 01/16/1988
• Status: Expired due to Term

• Current Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Original Assignee: ALPS Electric Company Limited (Alps Alpine Co., Ltd.)
• Inventors: Furudate, Mitsuru
• Primary Examiner(s): Lazarus, Ira S.
• Assistant Examiner(s): NEILS, PEGGY A
• Application Number:
  US07/244,887
• Time in Patent Office: 579 Days
• Field of Search: 362/26, 362/30, 362/31, 362/23, 362/307, 362/311, 362/333
• US Class Current: 362/615
• CPC Class Codes: G02B 6/0018 Redirecting means on the surface of the light guide
• 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: G02B 6/0046 Tapered light guide, e.g. wedge-shaped light guide

Abstract

An illumination light transmitting device comprising a rectangular illumination light transmitting body and a light source disposed outside an illumination range of the body or at an end portion of the body. The body has an illuminating portion formed with an oblique surface at the other end portion of the body on the opposite side of the light source. The oblique surface is formed with plural curved grooves. The light from the light source is transmitted through the body and is reflected on the curved grooves in various directions, thereby ensuring uniform illumination with effective irregular reflection.

Claims

1. An illumination light transmitting device comprising:

an external light source; and

a rectangular illumination light transmitting body having an upper portion including a substantially flat surface and a surface positioned so as to form an oblique angle with said flat surface and having a plurality of curved grooves formed therein, a lower portion having a substantially flat surface, and a light reflective side surface;

wherein said external light source is disposed opposite said flat surface of said upper portion and light from said external light source is reflected by said side surface onto said surface having a plurality of curved grooves formed therein.