Walter S Piskorowski

US Patent:

50993593, Mar 24, 1992

Filed:

Sep 11, 1990

Appl. No.:

7/580682

Inventors:

Anna L. Hrycin - Rochester NY
James R. Milch - Pittsford NY
Walter S. Piskorowski - Spencerport NY

Assignee:

Eastman Kodak Company - Rochester NY

International Classification:

G02B 110

US Classification:

359587

Abstract:

A composite optical interference filter is used in a film scanning system having a high speed CCD imager. Multiple, alternating, variable thickness layers of higher and lower index thin film oxides deposited on an optically transmissive substrate constitute the filter and enable the filter to provide color balance, notch rejection, and IR rejection all in the same device. Three such filters in a lamphouse of the film scanning system can be selected to match the system spectral response of the CCD imager and the film thereby providing equal density and color balance of the images on the film.