The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 19, 1988
Filed:
Oct. 23, 1985
Takehiko Kitamori, Hitachi, JP;
Shunsuke Uchida, Hitachi, JP;
Satoru Kawasaki, Hitachi, JP;
Masahiro Kondo, Hitachi, JP;
Hitachi, Ltd., Tokyo, JP;
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 with the intensity-modulated light, and containing liquid to be measured, at least one phase detection device for detecting the phase of the photoacoustic signals coming from the cell, a calculating device for analyzing impurities in the liquid on the basis of this phase detection device, and a control device for controlling the modulation frequency (light modulation frequency) of the intensity-modulated light in the light modulator.