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:
Jan. 29, 2002
Filed:
Aug. 16, 1999
Yuan-Chin Lee, Hsinchu, TW;
Zu-Wen Chao, Hsinchu, TW;
Industrial Technology Research Institute, Hsinchu, TW;
Abstract
This invention concerns a reading-writing pickup head for data access on optical record media. The pickup head of the present invention includes a birefringent prism and a quarter-wave plate where the birefringent prism is made of double-refraction material with different refraction indices on different polarizations, and it is used to split the incident and reflection beams of the pickup head. According to the present invention, the prism and the polarized beam splitter of a pickup head of the related art are replaced with the birefringent prism. Consequently, the number of optical elements of the pickup head according to the present invention is reduced.