The Measurement of CRT Beam Apertures

There are several ways to determine the optical performance of a cathode-ray tube assembly. Among the most well known are the resolution chart and the microscopic measurements of a single stationary spot. Although these methods have their advantages, they are lacking in some respects which are valuable to the designer and producer of television receivers. The limiting resolution test does not provide an adequate measure of performance, while the single spot measurement fails to take into account the effects of scanning. Neither method deals directly with the most significant measurement in regard to performance, this being the detail contrast reproduced for representative modulating frequencies.