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:
Mar. 19, 1996
Filed:
Mar. 24, 1995
John H Dunlavy, Colorado Springs, CO (US);
Haynes and Boone, L.L.P., Dallas, TX (US);
J. D. Technologies, Inc., Colorado Springs, CO (US);
Other;
Abstract
Method and apparatus for correcting distortion in a CD recording and playback system is disclosed. In an improved CD recording and playback system of the present invention, a complex reference signal having precisely defined amplitude and frequency properties is recorded on an information track of a CD prior to the beginning of the audio track(s). During playback of the CD, the reference signal is read from the CD and compared with a identical copy of the reference signal, which is stored in a memory device within the playback system. By of such comparison, every discernible and measurable difference between the read and the stored reference signals are established, defined and converted into a difference-information signal, which is used to resolve the necessary corrections that must be made in the playback system to render the two reference signals identical with respect to all amplitude components versus frequency and time components, as well as to correct the frequency and amplitude properties of the playback system in a manner that results in the playback system having a degree of accuracy that renders the reproduced signals virtually indistinguishable from the source signals.