The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 30, 1990
Filed:
Sep. 01, 1988
Makotoi Iwahara, Yokohama, JP;
Itsuo Takanashi, Kamakura, JP;
Shintaro Nakagaki, Fujisawa, JP;
Horosi Ichimura, Yokohama, JP;
Ichiro Negishi, Yokohama, JP;
Masaru Osada, Yokosuka, JP;
Wataru Katase, Yokohama, JP;
Victor Company of Japan, Ltd., Yokohama, JP;
Abstract
An image pickup device comprises an image pickup tube and an index generator having a light shield box; a light emitting diode held in the light shield box; a stripe screen provided on the photosensitive layer of the image pickup tube and shading compensation filter having transmittance pattern which equalizes illuminance variation on the stripe pattern of the stripe screen caused by the light emitting diode so that illuminance at any point of the stripe pattern becomes uniform. The image pickup tube generates picture signal together with index signal which is derived from the projected stripe pattern image on peripheral portion of the photosensitive layer through the shading compensation filter which equalizes index signal output level to make timing derived from the index signal accurate. A method of providing shading compensation filter is disclosed where a sheet of negative film is placed on the opening of the light shield box, exposed to the light emitting diode. Then the sheet of film is developed by chemical process.