Patent · US Expired

Method and apparatus for measuring particles in a fluid

US5621523A · kind A · utility

62Cited by
8References
13Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 20, 1995
Grant dateApr 15, 1997
Priority date
Expiry dateMar 20, 2015

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N2021/4726
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A particle-containing fluid in a sample cuvette is irradiated by a laser beam from a light source section. The scattered light thus produced passes through converging lenses and a mask and impinges on an etalon interferometer. The etalon only transmits scattered light (Rayleigh scattered light) that is of the same wavelength as the light emitted by the laser light source. The transmitted scattered light components impinges on a photomultiplier, and based on the intensity of the light a calculating section sorts the particles according to size and calculates the number of particles per unit flow amount, the particle size distribution and so forth. To enable adjustments to be made to compensate for the environmental dependency characteristics of the etalon, a control unit is provided which consists of a photodiode and mirrors.

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