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:
Oct. 03, 1989
Filed:
Dec. 11, 1987
Toshiaki Tsuyoshi, Kokubunji, JP;
Masatoshi Ohtake, Ome, JP;
Wasao Takasugi, Higashiyamato, JP;
Seiji Yonezawa, Hachioji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a light spot position control system and method in which a control of the irradiation position of a light spot such as a focusing control, a jitter correction and/or a tracking control is made through a sampling control, a newly sampled error value is compared with a one-preceding sampled value. When a difference between both the values is within a range of a predetermined width, the newly sampled value is used as a new sample value as it is. When the difference exceeds the range of the predetermined width, a sum of the one-preceding sampled value and the predetermined width is used as a new sample value. Thereby, the influence of erroneous samples is reduced.