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:
Dec. 29, 1998
Filed:
Jan. 05, 1996
Bruce V Johnson, Berkeley, CA (US);
Gregory A McDermott, San Francisco, CA (US);
Michael P O'Neill, Richmond, CA (US);
Cezary Pietrzyk, Pinole, CA (US);
Steven Spielman, Berkeley, CA (US);
Terrence L Wong, San Francisco, CA (US);
Calimetrics, Alameda, CA (US);
Abstract
The present invention is a system for reading a CD having a surface with a multiple level data track including a laser, a focusing and positioning system configured in a way which causes the laser to follow the multiple level data track, a detector which converts the light which is reflected from the data track to an electrical signal, a digital signal processing unit configured to receive the electrical signal including a scaling-function generator for determining a plurality of signal windows from the electrical signal, and a multiple level analog to digital converter which determines a data level based on the signal windows and the electrical signal whereby multiple data levels may be read from the CD.