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:
Nov. 24, 1992
Filed:
Dec. 17, 1990
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G01N / ;
U.S. Cl.
CPC ...
250573 ; 356 39 ;
Abstract
According to the present invention, the accuracy of particle size histograms produced from data relating to an impedance variation (Coutler Counter Method) caused by particles passing between electrodes disposed on either side of an orifice through which the particles pass is improved by excluding false data from the data used in producing the histograms, the false data resulting from more than one particle being resident in the orifice at a given data collection time. The preferred embodiment employs a light detecting method and apparatus to detect false readings and to provide correction information used to correct data obtained by the Coulter Counter Method and apparatus.