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:
Jun. 09, 1992
Filed:
Mar. 16, 1990
Applicant:
Inventors:
Kenneth H Levin, Silver Spring, MD (US);
Frank Y Li, Silver Spring, MD (US);
Assignee:
Infrared Fiber Systems, Inc., Silver Spring, MD (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ; G01N / ; G01N / ;
U.S. Cl.
CPC ...
250339 ; 250343 ; 356 51 ; 359285 ;
Abstract
An acousto-optical filter (AOTF) is used in a spectrometer for analysis of samples. The spectrometer provides continuous wave RF excitation through the crystal, and the spectrometer provides control and modulation for said RF source. The signal to noise ratio is improved by use of a lock-in amplifier which demodulates the modulation frequency. Fiber optics are used to connect the crystal to the source, and the source to the detection system. A digital lock-in amplifier is designed which increases the efficiency, accuracy, sensitivity and decreases the cost of conventional analog lock-in amplifier.