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. 13, 1993
Filed:
Nov. 04, 1991
Kabushiki Kaisha Toyota Chuo Kenkyusho, Aichi, JP;
Abstract
An electromagnetic field intensity measuring apparatus capable of measuring an electromagnetic field intensity accurately and sensitively without affection by any disturbance, including a measuring light generating section for emitting a measuring light containing first and second polarized light components which are orthogonal to each other and slightly different in frequency from each other; an optical input polarization-maintaining fiber for receiving one of the first and second polarized light components in the direction of X-axis polarization and the other polarized light component in the direction of Y-axis polarization, the optical input polarization-maintaining fiber conducting the measuring light to the electromagnetic field measuring place; a sensor section disposed in the electromagnetic field measuring place, the sensor section receiving the measuring light from the optical input polarization-maintaining fiber and modulating the phase of the incident measuring light depending on the electromagnetic field intensity; and an optical output polarization-maintaining fiber for receiving one of the first and second polarized light components from the sensor section in the direction of X-axis polarization and the other polarized light component in the direction of Y-axis polarization, the optical output polarization-maintaining fiber conducting the measuring light outside the electromagnetic field measuring place. The phase difference between the first and second polarized light components contained in the measuring light from the optical output polarization-maintaining fiber is detected to determine the electromagnetic field intensity.