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. 17, 1991
Filed:
Jun. 21, 1988
Ryo Akiyama, Hirakata, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
An optical disc apparatus comprising an optical servo loop and a velocity servo loop to control the velocity of a pickup to zero, wherein the two servo loops are selectively switched in accordance with the set mode of disc playing or the state of such playing. When a fast access is executed, the pickup is controlled by the velocity servo loop to avert undesired vibration in the travel of the pickup and also to protect the optical servo from any shock that may otherwise be caused by the travel and halt of the pickup. And in playing of any disc having a large number of dropouts, the velocity servo loop is closed during the existence of such dropouts to keep the optical servo loop from receiving a disturbance signal generated due to the dropout, thereby ensuring stable reproduction of signals from the disc.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile