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:
Jun. 05, 2001
Filed:
Jul. 12, 1999
Shin-ichi Hamaguchi, Amagasaki, JP;
Yuzo Shimizu, Mukou, JP;
Toru Tsuruta, Suita, JP;
Masanori Hirose, Nagaokakyou, JP;
Matsushita Electronics Corporation, Osaka, JP;
Abstract
An object is that stray light carriers are absorbed, and hence a signal larger than actual signal will not be outputted, thereby to output more precise signals. For achieving the foregoing, a concave portion is provided on the surface of a semiconductor substrate, a light receiving element for signal detection is provided around the concave portion, a semiconductor laser element is mounted in the concave portion, and a light shielding area is provided on the side existing between the semiconductor laser element and the light receiving element for signal detection of the sides of the concave portion. This causes stray light contained in the light emitted from the semiconductor laser element to be cut off at the light shielding area. Consequently, around the light receiving element for signal detection, the occurrence of stray light carriers on the surface of the semiconductor substrate can be prevented, and hence the stray light carriers are not absorbed by the light receiving element for signal detection. Therefore, the signal of an optical recording medium can be outputted with more precision.