Two-Dimensional Definition of Camera Tubes in a High-Definition Television System.

It is to be expected that in television systems with large numbers of lines, there will be some overlap of adjacent scans in the camera tubes. This overlap, and the general effect of interaction between the electron beam and the electronic image, lead to better definition on the tube target, a good dynamic response (lag), an anisotropic definition, and a situation in which an increase in target diameter is not accompanied by a corresponding increase in the definition. The manufacturer's data must be carefully studied with regard to the definition of camera tubes, if precise details are not available for a test pattern and for the scanning standard being considered. The disadvantages of anisotropic definition can be compensated by digital two-dimensional aperture correction.