Title:
DISTANCE METERING DEVICE AND METHOD
Document Type and Number:
Japanese Patent JP2015194347
Kind Code:
A
Abstract:
PROBLEM TO BE SOLVED: To allow an optical lens system of a simple configuration to accurately meter an objective distance to an object.SOLUTION: After reflection light from an object T is diffracted by a diffraction grating 14, a condenser lens 15 converges the diffraction light on an image formation plane Q, and a spatial filter 16 placed on the image formation plane Q transmits only diffraction light of preliminarily set two different orders of the diffraction light, and blocks diffraction light of other orders. An optical detection element 17 detects an interference fringe generated in a detection plane I by the diffraction light of the different two orders passing through the spatial filter 16, and a distance calculation unit 18 performs computation processing of the obtained detection result to extract a pitch of the interference fringe, and calculates an objective distance a from the condenser lens 15 to the object T on the basis of the pitch.
Inventors:
FUJIWARA HISATOSHI
Application Number:
JP2014071085A
Publication Date:
November 05, 2015
Filing Date:
March 31, 2014
Export Citation:
Assignee:
AZBIL CORP
International Classes:
G01B11/00; G01B9/02
Domestic Patent References:
| JP2004028977A | 2004-01-29 | |||
| JPH10141912A | 1998-05-29 | |||
| JPH0861920A | 1996-03-08 | |||
| JPH0773502A | 1995-03-17 |
Foreign References:
| US20020149691A1 | 2002-10-17 |
Attorney, Agent or Firm:
Masaki Yamakawa
Shigeki Yamakawa
Shigeki Yamakawa