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, 1991
Filed:
Aug. 18, 1989
Jennifer L Randall, Lancaster, PA (US);
Burle Technologies, Inc., Wilmington, DE (US);
Abstract
A vertical phase adjust circuit with high noise immunity for line locked surveillance cameras. To prevent noise from the AC line producing false output signals, a counter is used to lock out the delayed vertical line locked output signal. The horizontal scan frequency is counted from the time a vertical output is produced, and the vertical output signal is prevented until 98 percent of the period between legitimate vertical signals has elapsed. The circuit also includes a lock detect circuit to increase the time window during startup conditions to assure initial synchronization and an increased phase adjust range to permit synchronization with any other camera.