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:
Jan. 30, 1990
Filed:
Mar. 29, 1988
John P Dakin, Hampshire, GB;
Philip B Withers, Hampshire, GB;
Plessey Overseas Limited, Ilford, GB;
Abstract
A Fabry-Perot pressure or displacement sensor comprises an optical fibre which serves to transmit a light beam to the mirrors of the sensor and to receive light which is reflected back from the mirrors. The light beam and the reflected light comprise light at a plurality of wavelengths. The wavelength components of the transmitted light and the wavelength components of the received light are range rated in range gates and are compared in comparators to provide respective ratios of transmitted intensities and received intensities. These ratios are in turn compared in comparator to provide a ratio dependent upon the displacement of the mirrors of sensor due to pressure applied thereto but independent of any changes in the intensities of transmitted light due to reflections from optical components in the pressure or displacement monitoring arrangement.