Minimum resolvable contrast measurement device

Details Minimum resolvable contrast measurement device Minimum resolvable contrast measurement device

1980-04-15

1981-11-10

Punter, William H.

Optics: image projectors

Plural projection paths with single light source

353 20, 353 85, 355 37, 355 69, 355 71, G02B 2718, G02F 101, G03B 2772, G03B 2100

Patent

active

042994519

ABSTRACT:
An apparatus for creating images of nonperiodic patterns, which patterns are variable in contrast with respect to a uniform and constant level of background luminance. Two beams of uniform luminance are projected through individual, orthogonally oriented linear polarizers, and then into a common cube beam splitter to be divided and interlaced. One combined output beam from the splitter is projected through a rotatable linear polarizer onto the image sensing optical detector undergoing test. The second beam is projected toward a detection system. The patterned region of the second beam passes through a second rotatable linear polarizer, synchronized to the first rotatable polarizer, and onto a CCD array detector system. Contrast between the pattern and the background is represented by the two electrical voltage levels in the array output, irrespective of the spatial frequencies in the pattern. Two unpatterned background regions from either of the interlaced beams are projected through individual and orthogonal linears polarizers to individual luminance detectors. Each detector, in turn, regulates its corresponding beam intensity to compensate for drift in the beam generating elements.

REFERENCES:
patent: 3498705 (1970-03-01), Ooue et al.
patent: 3679306 (1972-07-01), Du Bois et al.
patent: 3873199 (1975-03-01), Weinert
patent: 3885866 (1975-05-01), Stearns
patent: 3926520 (1975-12-01), Kaufman
patent: 4167024 (1979-09-01), Hamisch
Kelly, D. H. "Visual Signal Generator" Rev. Sci. Instru. vol. 32, #1, 1-1961, pp. 50-55.

Affiliated with

Also associated with

Rating

Minimum resolvable contrast measurement device does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Minimum resolvable contrast measurement device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Minimum resolvable contrast measurement device will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2359823