The horizontal resolution of a television system is the ability of the scanning system to resolve the horizontal details i.e., changes in brightness levels of elements along a horizontal scanning line. Since such changes represent vertical edges of picture detail, it follows that horizontal resolution can be expressed resolution as a measure of the ability to reproduce vertical information.
The horizontal resolution in a scanning system depends on the rate at which the scanning spot is able to change brightness level as it passes through a horizontal line across the vertical lines of resolution shown in Fig. 30.9.
Fig. 30.9 Horizontal resolution and video bandwidth requirements
In the 625 line ...