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. 21, 1992
Filed:
Sep. 11, 1989
Toshiaki Fukuma, Kyoto, JP;
Shimadzu Corporation, Kyoto, JP;
Abstract
A spectrophotometer comprising a light source, a spectroscope which separates the light of light source depending on the wavelengths, chops the light into the first and second light beams and allows the light beams to pass through the reference cell and sample cell, a photodiode which alternately receives the light beams from the reference cell and sample cell, a variable gain amplifier which amplifies a light current of photodiode, an A/D converter which converts and guides the reference output and sample output as the digital values synchronously with the chopping period, and a again setter which sets the gain of the variable gain amplifier depending on the reference output value from the A/D converter.