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:
Aug. 06, 1991
Filed:
Jan. 09, 1991
BTS Broadcast Television Systems GmbH, Darmstadt, DE;
Abstract
A test pattern generator for digital television signals produces a zone plate pattern on an orthogonal pixel raster generated by pixel and line counters. The counter outputs are supplied to respective ROMs each storing a parabolic function. Their outputs are added to define zone plate circles on the basis of the circle equation x.sup.2 =y.sup.2 =r.sup.2. Circular patterns of evenly spaced color bars are produced by interposing a square root extracting ROM ahead of another ROM which converts the phase values into amplitude values. The optional interposition of a square root function after the addition and before the conversion into amplitude values provides a different circular test pattern. It can be readily modified in various ways under control of a microprocessor or EPROM.