Patent · US Expired

Liquid level sensor with wide temperature range capacity

US4962395A · kind A · utility

16Cited by
4References
21Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 6, 1988
Grant dateOct 9, 1990
Priority date
Expiry dateDec 6, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S250/903
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A liquid level sensor comprises a light source in the form of a semiconductor device, a light sensor also in the form of a semiconductor device, and an optical element arranged to transmit light from the light source and to receive reflected light and transmit it to the light sensor, the liquid level sensor further comprising a carrier having gas-filled cavities means in which the light source and the light source and the light sensor are respectively mounted, the cavities being separated by barrier means to prevent scattered light reaching the light sensor from the light source. The mounting of the light source and light sensor in gas-filled cavities extends significantly the operating temperature range of the liquid level sensor.

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