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:
Sep. 24, 1991
Filed:
Feb. 02, 1989
Mitsubishi Denki Kabushiki Kaisha, Tokyo, JP;
Abstract
The present invention relates to an optical recording and/or reproducing apparatus which optically carries out operations of recording and/or reproducing of information on a data carrier, by irradiating a beam from an optical head to the data carrier. In the apparatus according to the present invention, the angle between the optical axis of the beam from the optical head and the surface of said data carrier is detected, and a temperature adjusting device brings about a difference in temperature between both surfaces of the data carrier on the basis of the detected result in respect to the angle. Then, the difference in temperature generates a thermal strain, and this thermal strain functions to cancel the strain which the data carrier has previously had. As a result, the surface of the data carrier is kept on a level, so that this surface can be vertical to the optical axis of the beam from the optical head. Therefore, in the optical recording and/or reproducing apparatus, easily maintained is the right angles between the surface of the data carrier and the optical axis of the beam, and the mechanism for focalizing the beam can be simplified to miniaturize the optical head. Furthermore, no mechanism for making the optical head oscillate is required, as a result, a high-speed accessibility is obtained.