Holographic subtraction with phase modulation to distinguish pha

Details Holographic subtraction with phase modulation to distinguish pha Holographic subtraction with phase modulation to distinguish pha

1977-10-05

1980-07-15

Stern, Ronald J.

Optics: measuring and testing

Document pattern analysis or verification

350 36, 350 377, 350 383, 350 386, 356347, G06K 908, G01B 9027, G03H 116, G03H 128

Patent

active

042125367

ABSTRACT:
Two substantially identically patterned transparencies, i.e. a master photomask and a copy thereof, are compared with each other by transluminating the master with an object beam, producing a hologram of that master by letting the object beam interfere with a reference beam from a common source of coherent light such as a laser, placing the copy in the path of the object beam formerly occupied by the master, and positioning the developed hologram at the intersection of the two beams to generate a compound beam of zero intensity if the two transparencies are identical. The luminous energy of the compound beam thus varies inversely with the degree of equivalency of the two transparencies. The compound beam may be imaged onto a receiving surface, with certain areas thereof blocked out to eliminate error indications from insignificant (e.g. marginal) zones.

REFERENCES:
patent: 3537854 (1970-11-01), Grobin et al.
patent: 3627426 (1971-12-01), Tsuryta et al.
patent: 3729634 (1973-04-01), Jensen et al.
patent: 3767285 (1973-10-01), Mezrich
patent: 3826555 (1974-07-01), Matsumoto
patent: 4024513 (1977-05-01), Huignard et al.
Neumann et al., Applied Optics, vol. 6, No. 6, Jun. 1967, pp. 1097-1104.
Bruning et al., IEEE Transactions on Electron Devices, vol. ed-22, No. 7, Jul. 1975, pp. 487-495.
Watkins, Applied Optics, vol. 12, No. 8, Aug. 1973, pp. 1880-1884.
Bromley et al., Applied Optics, vol. 10, No. 1, Jan. 1971, pp. 174-181.

Affiliated with

Also associated with

Rating

Holographic subtraction with phase modulation to distinguish pha does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Holographic subtraction with phase modulation to distinguish pha, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Holographic subtraction with phase modulation to distinguish pha will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-461573