Spread illuminating apparatus with cover provided over transparent substrate

• US 20020106182A1
• Filed: 01/31/2002
• Published: 08/08/2002
• Est. Priority Date: 02/02/2001
• Status: Active Grant

• Current Assignee: Minebea Company Limited (MinebeaMitsumi Inc.)
• Original Assignee: Minebea Company Limited (MinebeaMitsumi Inc.)
• Inventors: Kawashima, Satoshi
• Granted Patent: US 6,895,163 B2
• Time in Patent Office: Days
• US Class Current: 385/146
• CPC Class Codes: G02B 6/0001 specially adapted for lighting devices or systems lighting or signalling on vehicles using light guides B60Q1/00; lighting devices for vehicle dashboards B60Q3/10; lighting devices for vehicle interior using light guides B60Q3/62; lighting devices mounted on the vehicle rear part using light guides F21S43/235; measuring arrangements having light conducting pointers G01D13/265; illumination of liquid crystal displays G02F1/1336; illuminated signs G09F13/00
• CPC Class Codes: G02B 6/0028 Light guide, e.g. taper
• CPC Class Codes: G02B 6/0031 Reflecting element, sheet or layer
• 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 6/0093 Means for protecting the light guide
• CPC Class Codes: G02B 6/0096 the lights guides being of the hollow type
• CPC Class Codes: G09F 13/0409 Arrangements for homogeneous illumination of the display surface, e.g. using a layer having a non-uniform transparency arrangements of reflectors G09F13/14

Abstract

There is provided a spread illuminating apparatus to ensure excellent light conductivity. A cover is integrally provided over a transparent substrate sandwiching a fluid (cushioning material) of a gel, liquid, or gaseous substance. With this structure, dust generated in assembly process is prohibited from getting on the transparent substrate, and even when other members or an assembly machine hit and bend the cover during the assembly process, the bending is absorbed by the fluid, and a light reflection pattern formed on the transparent substrate is protected against damages, whereby excellent light conductivity can be maintained.

Claims

1. A spread illuminating apparatus comprising:

a transparent substrate made of a light-transmissible material and having a light reflection pattern formed on at least one surface thereof; and

a bar-like light source disposed close to an end surface of the transparent substrate, wherein a cover formed of a light-transmissible material is integrally provided over the one surface of the transparent substrate sandwiching a cushioning material consisting of a light-transmissible substance.

2. A spread illuminating apparatus according to claim 1, wherein the cushioning material is of a substance with low refractive index.

3. A spread illuminating apparatus according to claim 2, wherein the substance is gel.

4. A spread illuminating apparatus according to claim 2, wherein the substance is liquid.

5. A spread illuminating apparatus according to claim 1, wherein the cushioning material is of a gaseous substance.

6. A spread illuminating apparatus according to claim 1, wherein a thin film of a substance with low refractive index is formed on the light reflection pattern of the transparent substrate, and the cushioning material is of a gel substance.

7. A spread illuminating apparatus according to claim 1, wherein a thin film of a substance with low refractive index is formed on the light reflection pattern of the transparent substrate, and the cushioning material is of a liquid substance.

8. A spread illuminating apparatus according to claim 1, wherein a thin film of a substance with low refractive index is formed on the light reflection pattern of the transparent substrate, and the cushioning material is of a gaseous substance.

9. A spread illuminating apparatus according to claim 1, wherein the cushioning material comprises a plurality of transparent elastic members.

10. A spread illuminating apparatus according to claim 1, wherein the cover is formed of a hard material.

11. A spread illuminating apparatus according to claim 10, wherein the hard material is glass.

12. A spread illuminating apparatus according to claim 10, wherein the hard material is transparent polymer.

13. A spread illuminating apparatus according to claim 1, wherein the cover constitutes a lower electrode substrate of a touch panel which may be disposed over the spread illuminating apparatus.