04131363 is referenced by 41 patents and cites 3 patents.

In a projection printing system the pattern mask, whose image is projected onto a light sensitive layer, is protected with a thin, 0.2-6 micron thick, transparent film or pellicle which is positioned an optically large distance of about 1-125 mm from the mask surface by a spacer member. Any dirt particles on the surface of the pellicle will be out of focus and are not printed in the light sensitive layer. A pellicle can also be employed to protect the light sensitive layer at the image plane.

Title
Pellicle cover for projection printing system
Application Number
5/857632
Publication Number
4131363
Application Date
December 5, 1977
Publication Date
December 26, 1978
Inventor
Walter J Wojcik
Poughkeepsie
NY, US
Vincent Shea
Poughkeepsie
NY, US
Agent
David M Bunnell
Assignee
International Business Machines Corporation
NY, US
IPC
G03B 27/62
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