A real‐time measurement system to evaluate image sharpness for CRT display
Haruo Isono · Systems and Computers in Japan · 1988
Abstract It is necessary to display clearly characters and figures in addition to ordinary pictures, for CRT displays of computer terminals and high‐definition televisions (HDTV). Among the factors constituting image quality of CRTs, image sharpness is important. This paper proposes a method of objective evaluation of the image sharpness of CRT displays, and describes a real‐time image‐sharpness evaluation system based on this method. In the system, the spatial‐frequency characteristics of the whole CRT display are measured quickly using a microprocessor. Then the value of the sharpness under given objective conditions is calculated using both the data observed and a mathematical model of a human‐visual system. It was confirmed that the image‐sharpness of TV‐receivers measured by this evaluation system agrees well with subjective evaluations. The proposed system provides a practical method of evaluating or predicting the image‐sharpness of CRT displays.