Radially varying transmission filter for wide angle copying devi

Details Radially varying transmission filter for wide angle copying devi Radially varying transmission filter for wide angle copying devi

1980-01-07

1981-11-03

Wintercorn, Richard A.

Photocopying

Projection printing and copying cameras

Illumination systems or details

350314, 354296, G03B 2772

Patent

active

042982758

ABSTRACT:
A neutral density filter with a radially varying transmission is inserted in close proximity to the projection lens in a photocopier optical system. The filter has a transmission profile which provides compensation for photoconductor irradiance falloff due to cos.sup.4 as well as other circularly symmetrical non-uniformities in the optical system such as lens exit pupil distortion.

REFERENCES:
patent: 2356694 (1944-08-01), Potter et al.
patent: 3279311 (1966-10-01), Lichtner
patent: 3397023 (1968-08-01), Land
patent: 3669538 (1972-06-01), Fowler
patent: 3777135 (1973-12-01), Rees
patent: 3981565 (1976-09-01), Karasawa
patent: 4229097 (1980-10-01), Vulmiere et al.
IBM Technical Disclosure Bulletin, "Illumination Compensation for Cos.sup.4 .theta. Lens Attenuation", G. W. Hobgood, Jr., vol. 14, No. 11, Apr. 1972, p. 3324.
Lenses in Photography, The Practical Guide to Optics for Photographers, Ch. VIII, "Lens Attachments", Kingslake, publ. for Garden City Books, Garden City, N.Y. 1951, p. 143.

Affiliated with

Also associated with

Rating

Radially varying transmission filter for wide angle copying devi does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Radially varying transmission filter for wide angle copying devi, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radially varying transmission filter for wide angle copying devi will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1062160