Patent · US Expired

Method for analyzing impurities in liquid and apparatus therefor

US4738536A · kind A · utility

8Cited by
1References
36Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 23, 1985
Grant dateApr 19, 1988
Priority date
Expiry dateOct 23, 2005

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01N21/1702
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method for analyzing impurities in liquid and an apparatus therefor are disclosed, which are adapted to classify impurities contained in various liquids to be measured into soluble substance, insoluble substance and impurities in the form of bubbles and to measure their concentration separately; especially the impurities in liquid are analyzed by the method such that photoacoustic signals obtained by irradiating a liquid to be measured with intensity-modulated light are measured; the correlation between the modulation frequency of the intensity-modulated light (light modulation frequency) and the phase of the intensity-modulated light, with which the liquid to be measured is irradiated, as well as that of their photoacoustic signals are obtained; and impurities in the liquid to be measured are detected, while classifying them into soluble and insoluble ones and those in the form of bubbles on the basis of the information thus obtained; and the apparatus comprises a light source, at least one light modulator for transforming light from the light source into intensity-modulated light having a given constant frequency, at least one cell disposed at a position, where it is irradiated…

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