Utilization of a Reseau for Reducing Electronic Scanning Nonlinearity in Surveyor Television Space Systems

Inherent in every TV imaging tube are the horizontal and vertical sweep nonlinearities resulting from sweep-speed variations across the face of the tube; these are due to the variation in beam travel distance and the physical limitations involved in regulating the electric and magnetic fields that control the scanning beam. Practical limitations on the degree to which these distortions can be controlled make very important certain extremely accurate procedures for subsequent correction of distortions. These distortions can be partially removed from either the output video signal or from the processed TV print or negative. The corrective process utilizes a matrix of marks called a reseau, which is affixed to the faceplate of the imaging tube. The number and spacing of the marks are dependent upon the accuracy of the distortion correction procedure and the acceptability criterion placed on residual distortion. Derivations are given for two Surveyor-developed linear-distortion correction processes which utilize a reseau. Several applications of the technique are cited.

Print ISSN

0361-4573

Published

1968-04

Content type

Original Research

DOI

10.5594/J05824