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:
Nov. 12, 2002
Filed:
Nov. 26, 1997
Applicant:
Inventors:
Assignee:
Snell & Wilcox Limited, Hampshire, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04N 7/01 ; H04N 1/120 ;
U.S. Cl.
CPC ...
H04N 7/01 ; H04N 1/120 ;
Abstract
A method for converting between relatively close field rates of perhaps 60 Hz and 59.94 Hz, monitors the phase difference between input and output field rates. Initially, output fields are created by synchronizing input fields. As the measured phase passes a threshold, the method switches to interpolation mode for a short, fixed interval and then returns to synchronization. The method offers much of the sharpness associated with simple synchronization but avoids the visible discontinuities of field drops or repeats.