Title: Surface deformation gauging system by moire interferometry

Abstract: A technique for comparing master parts with replicas to determine differences in shapes or sizes, is disclosed, which uses interferometric techniques as disclosed. A television camera is used to scan the pattern established by illuminating the subject with a set of optical fringes. An objective lens images these on a transmission line grating. A television camera scans the transmission grating. The spatial frequencies of the subject fringes and of the grating are especially selected so that the camera can not resolve either of them but can resolve their difference. As a result, the output signals of the camera represent a contour map of the object placed on a low frequency spatial carrier, but yet, the measurement sensitivity is still determined by the spatial frequency of the subject fringes.

Do you think this is a good invention? Vote now:

Votes so far: For:(0) Against:(0)
Other info:

Inventors: Ramsey, Jr., Stevens David (Palo Alto, CA, US)

Application Number: 499486
Filing Date: 1974-08-22
Publication_date: 1976-03-09
Assignee: Stanford Research Institute (Menlo Park, CA)
Primary Class(es): 348/130 356/394, 356/511, 356/605
Other Classes:
US Patent Ref:

3511571	May, 1970	Ogle	356/167.
3614232	Oct, 1971	Mathisen	350/162.
3634695	Jan, 1972	Barrington	350/162.
3735036	May, 1973	Macovski	178/6.
3768907	Oct, 1973	Williams	350/162.
3814521	Jun, 1974	Free	356/167.
3828126	Aug, 1974	Ramsey	178/DIG.

Other Refs:
Primary Examiner: Britton, Howard W.
Assistant Examiner: Masinick, Michael A.
Attorney: Lindenberg, Freilich, Wasserman, Rosen & Fernandez