Patent · US Expired

Device for optically measuring a pressure differential

US5128537A · kind A · utility

39Cited by
5References
12Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMay 15, 1991
Grant dateJul 7, 1992
Priority date
Expiry dateMay 15, 2011

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01L9/0079
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A device for optically measuring a pressure difference in a medium by means of a Fabry-Perot interferometer, comprises a transparent plate and a diaphragm block connected to the transparent plate, the diaphragm block comprising a substrate, a measuring diaphragm formed along the inner surface of the substrate, and a spacer separating the inner surface of the transparent plate and the inner surface of the substrate. A first planar mirror is disposed on the inner surface of the plate and a second planar mirror is disposed on the inner surface of the measuring diaphragm so that they constitute the Fabry-Perot interferometer. The measuring diaphragm is shiftable by a distance (H) in response to a pressure difference (.delta.p) exerted on inner and outer surfaces of the measuring diaphragm whereby the optical length (L) of the Fabry-Perot interferometer changes as a function of the pressure difference (.delta.p). The substrate includes a depression on one side only so that the material remaining under the depression is of a predetermined thickness and comprises the measuring diaphragm. Since the measuring diaphragm constitutes a portion of the substrate and is a continuation of the crys…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.