Title:
LIGHT BEAM OVERLAPPING APPARATUS
Document Type and Number:
Japanese Patent JPH01138526
Kind Code:
A
Abstract:
PURPOSE: To prevent the occurrence of disorder of an interference signal due to the temperature change by providing a light-transmissive mirror coating part on a part of the coupling surface of one of two partial prisms and providing partial coating parts, which reflect light covering the areas of respective light incidence points, on outside surfaces of two partial prisms. CONSTITUTION: A light-transmissive semitransparent mirror coating part 12 is provided on a coupling surface where two partial prisms 7 and 7' are fixed to each other, and light reflecting coating parts 10 and 10' are provided on outside surfaces of partial prisms 7 and 7'. When light beams 1 and 2 are made incident from specific incidence points in bottoms of partial prisms 7 and 7', they are reflected by light reflecting coating parts 10 and 10' on outside surfaces and are made incident on the semitransparent mirror coating part 12 on the inside surface. Each light beam made incident on the semitransparent mirror coating part 12 is divided into reflected partial light and transmitted partial light. Thus, the influence of phase deviation of optical waves due to the temperature variance is eliminated because optical paths of respective light beams have the same length practically, and disorder of the interference signal doesn't occur.
Inventors:
HANSU YAA BUTSUSHIERUBERUGAA
Application Number:
JP18667388A
Publication Date:
May 31, 1989
Filing Date:
July 26, 1988
Export Citation:
Assignee:
LITEF GMBH
International Classes:
G01C19/66; G02B27/10; G02B27/14; G01C19/64; H01S3/083; (IPC1-7): G01C19/64; G02B27/10; H01S3/083
Foreign References:
| US4582429A | 1986-04-15 | |||
| US3218916A | 1965-11-23 |
Attorney, Agent or Firm:
Aoyama Ryo (1 person outside)
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