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:
Apr. 11, 1978
Filed:
Jan. 20, 1976
Yukio Okano, Osaka, JA;
Minolta Camera Kabushiki Kaisha, Osaka, JA;
Abstract
A two dimensional optical phase grating filter is provided that is capable of limiting the transmittance of spacial frequency signals in one or more scan directions. The two dimensional grating of the present invention can be utilized as an optical low pass filter to improve image resolution in a color video system. In the color video system, the two dimensional grating filter could be designed to optically complement a dichroic stripe filter to prevent the introduction of spurious signals by any interference of luminance and chrominance signals. The design parameters of the present invention provide an improved cut-off characteristic with grating widths larger than one-half of the filter period. The two dimensional phase grating filter of the present invention can also be utilized in other optical systems, such as an automatic focusing system, where it is desired to pass only a certain spacial frequency as a monitored signal for the automatic adjustment of the focus of the optical system.