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:
May. 28, 1991
Filed:
Dec. 29, 1989
Samsung Electronic Co., Ltd., Suwon, KR;
Abstract
A laser pick-up device for an optical disk receives three laser beams to irradiate the optical disk and uses a six-division optical detector to detect the laser beams reflected from the optical disk and to track exactly the optical disk. A reflection type diffraction grating is positioned at a front position in order to divide and reflect the laser beam generated by a laser diode. A holographic element having the function of a toric lens is used as a diffracting device for the reflected beams. The six-division optical detector is positioned to one side and/or behind the diffraction grating. The grid gaps of the holographic element can be larger using the present invention which simplifies the manufacturing the holographic element and thereby provides a laser pick-up device that is suitable for mass production.