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:
Aug. 21, 1979
Filed:
Dec. 09, 1977
David H Vilkomerson, Princeton, NJ (US);
Abstract
A method and apparatus for directly obtaining displacement-amplitude information from a quadrature-dual interferometer. The system uses a 'mini-wiggler' to introduce phase shift into the reference beam, as by oscillating a reference mirror with a piezo-electric crystal. The mini-wiggler produces relatively small phase perturbations of the order of 0.001.lambda. at a frequency at either edge or in the middle of the signal frequency band. The system uses a signal-processing circuit to obtain displacement amplitude directly. The purpose of the mini-wiggler is to produce a 'pilot' signal of known amplitude and phase from which the correction terms needed to compensate for variations in the interferometer state, such as those caused by vibration, large variation, drift, and the like, are derived and can be applied by means of another signal processing circuit.