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:
Feb. 11, 1992
Filed:
Aug. 07, 1990
Hitachi Video Engineering, Inc., Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a dust removing system, the level of influence of dust sticking to an objective lens of an optical head is detected from either an amount of light emitted from the optical head and reflected from an optical head or from an access time. Three stages of levels with regard to the degree of influence of the dust are set in accordance with such detection value, and a different message for the removal of dust is indicated on a display unit in response to the level of the influence. When the influence is low, a dust removing mechanism is automatically rendered operative to remove the dust. At the first level at which the influence of dust is low, the optical disk in the optical disk device is discharged and cleaning of the objective lens is performed, and an indication is provided on the display unit representing that cleaning is proceeding. When the second stage is detected, the optical disk in the optical disk device is discharged, and a message is indicated on the display unit representing that cleaning of the objective lens should be performed using a cleaning disk. When the third stage is detected, a message is indicated on the display unit representing that cleaning of the objective lens should be performed by manual operation.