Title:
FILM LENS FOR SURFACE LIGHT SOURCE AND SURFACE LIGHT SOURCE USING SAME
Document Type and Number:
Japanese Patent JP3424136
Kind Code:
B2
Abstract:
PURPOSE: To increase luminance in a normal direction and make a luminance distribution uniform by arranging unit lenses in specific shapes alternately on one surface of a transparent base material so that their ridges are parallel, and making the other surface flat.
CONSTITUTION: A transparent lens part 3 is formed on a base material film 2 or formed directly of a transparent material film. The lens part 3 has two different kinds of triangular prisms 3A and 3B, which are in axially symmetrical main cut surface shapes in mirror image relation, arranged alternately. In this case, the vertical angle α is 60-120°C, the base angles β and γ are not equal to each other, and the lengths L1 and L2 of the sides including the vertical angle α are different and the length of each side including the vertical angle αis equal to the lengths of continuous sides among the sides of adjacent triangular prisms; and the unit lenses are thus arranged so that the ridge directions are parallel. The other surface of this film lens is flat, but fine unevenness 4 may be provided on the flat surface.
Inventors:
Hiroyuki Amemiya
Application Number:
JP4468194A
Publication Date:
July 07, 2003
Filing Date:
February 21, 1994
Export Citation:
Assignee:
Dai Nippon Printing Co.,Ltd.
International Classes:
G02B6/00; G02B5/02; G02F1/1335; G02F1/13357; (IPC1-7): G02B5/02; G02B6/00; G02F1/13357
Domestic Patent References:
| JP618707A | ||||
| JP5313004A |
Attorney, Agent or Firm:
Satoshi Kanayama
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