Optics: measuring and testing – By polarized light examination – With light attenuation
Patent
1989-05-31
1990-12-18
Evans, F. L.
Optics: measuring and testing
By polarized light examination
With light attenuation
G01B 1116, G01B 1124
Patent
active
049782223
ABSTRACT:
Periodic motions are analyzed by generation of real time moire fringe images. A line grating mounted on the object (1) surface is photographed using a rigidly supported camera (4) from an oblique angle to the plane of the grating. A negative transparency of the line grating is placed within the camera (4) supported by a glass plate and, with the shutter open, the transparency is first registered with the instant image of the stationary line grating then skewed to produce mismatch fringes. A TV camera (6) monitors the subsequent interaction between the skewed negative and the instant image of the line grating on the moving object (1) as seen on the glass plate at the camera image plane and this interaction is displayed on a TV monitor (10). The image is characterized by the presence of a secondary fringe phenomena indicative of object displacements.
REFERENCES:
patent: 4459027 (1984-07-01), Kafri et al.
"Projection-Imaging Moire", National Physical Laboratory, MOM h 78, Crown copyright 1987.
"Double Fringe Patterns Measure Vibration", Eureka Transfers Technology, Jul. 1988, pp. 36 and 37.
Optical Engineering, vol. 24, No. 4, Jul./Aug. 1985, (Bellingham, Washington, U.S.A.), D. Post: "Moire Interferometry for Deformation and Strain Studies", pp. 663-667.
Journal of Phycis E; Scientific Instruments, vol. 8, No. 9, Sep. 1975, (Havant, GB), C. A. Miles et al, "Recording the Shape of Animals by a Moire Method", pp. 773-776.
Applied Optics, vol. 22, No. 6, 15 Mar. 1983, Optical Society of America, (N.Y., U.S.A.), K. G. Hardin et al., "Projection Moire Interferometer for Vibration Analysis", pp. 856-886.
Soviet Journal of Nondestructive Testing, vol. 20, No. 12, Dec. 1984, Plenum Pub. Corp. (N.Y., U.S.A.), S. T. De et al, "Using the Moire Pattern of Interference Fringes for Detecting Defects", pp. 772-779.
Drew Walter
Pyne Clive R.
Evans F. L.
The Secretary of State for Defence
LandOfFree
Analysis of periodic motions using moire fringes does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Analysis of periodic motions using moire fringes, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Analysis of periodic motions using moire fringes will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1422609