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:
Dec. 31, 1991
Filed:
Aug. 07, 1989
Katsumi Takeda, Yokohama, JP;
Tadashi Saitoh, Fujisawa, JP;
Masashi Mori, Chigasaki, JP;
Toshihiro Matsunaga, Kamakura, JP;
Hitachi, Ltd, Tokyo, JP;
Hitachi Video Eng. Inc., Kanagawa, JP;
Abstract
An optical recording and reproducing system having an accurate high-speed optical head positioning apparatus. In one embodiment, a positive acceleration is applied to the optical head until the optical head has moved half the distance to a target track. Thereafter, a negative acceleration is applied to the optical head to decelerate the optical head until the optical head arrives at the target track. Feedback control is not used while the optical head is moving, thus eliminating a delay in response time due to a limited servo band upon the transition from the positive acceleration to the negative acceleration.