The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 26, 1988
Filed:
Jun. 10, 1986
Applicant:
Inventor:
Dietrich Meier, Erlinsbach, CH;
Assignee:
Kern & Co. AG, Aarau, CH;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G01C / ; H01S / ;
U.S. Cl.
CPC ...
356-5 ; 332-751 ;
Abstract
For electrooptical measurement of distance with modulation of light external to the light source (1) a modulator system (5, 7, 8, 11) with low sensitivity to temperature and with a low modulating voltage is disclosed. The temperature dependence of the static birefringence of a modulating crystal (7) is compensated by passing the modulated light beam (6), after traversing the crystal (7), a quarterwave plate (11), the measured path (9) and the quarterwave plate (11) again--a second time through the crystal (7) with its polarization rotated by 90.degree.. The light beam returning from the measured path is separated from its source (1) by means of a polarizing beam splitter (5).