Patent · US Expired

Total-reflection type refractive index sensor

US5565978A · kind A · utility

33Cited by
2References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 13, 1994
Grant dateOct 15, 1996
Priority date
Expiry dateDec 13, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/43
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A refractive index sensor of a total-reflection type comprises a waveguiding layer of a cladding/core/cladding waveguide structure formed on a substrate. The waveguiding layer has an input face connected to either a single optical fiber or a plurality of optical fibers for injecting a light(s) into the layer, a detection face which, obeying Snell's law, totally reflects/transmits the light beam or beams that have arrived there with an expansion angle from the optical fiber or fibers and which constitutes a surface with which a material whose refractive index is to be measured comes in contact, and an output face which outputs the light reflected from the detection face and is connected to an optical detector. The refractive index of the material of interest is detected from a bright-dark boundary of the presence of the corresponding total reflected light from the detection face. With no need of a bulk prism or lamp-type light source, the sensor is small in size and high in sensitivity.

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