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. 06, 1984
Filed:
Sep. 13, 1982
Duane T Thompson, Franklin, MA (US);
Edwin L Karas, Sharon, MA (US);
Ernest F Root, Nashua, NH (US);
Fredrik Schlyter, Fairfield, CT (US);
The Foxboro Company, Foxboro, MA (US);
Abstract
An interferometer mirror drive system compensates for velocity and tilt errors induced by ambient vibration, as well as providing long-term automatic alignment of the mirrors. A uniquely configured .lambda./8-thick step on the fixed mirror of the interferometer introduces a 90-degree phase shift in one of two reference light beams, to produce quadrature signals which characterize the relative motion between the fixed and the driven mirrors. An electronic circuit extracts velocity and tilt data from the quadrature signals and develops error signals indicative of deviations from the desired coordinates of the moving mirror. The error signals are used to generate a set of control signals which in turn are supplied to an arrangement of drive coils attached to the moving mirror, to restore the mirror to the desired coordinates.