| 摘要 |
PURPOSE:To automatize quantitative measurement at a production time and improve precision by using a black-and-white TV camera to pick up the screen of a receiver and comparing left and right size marker signal positions with each other in respect to time. CONSTITUTION:White signal 5, which projects white raster throughout the available picture area, and signals 6 and 7, which project horizontal and vertical size markers in horizontal and vertical symmetrical positions in respect to the center of horizontal and vertical scanning periods respectively, are supplied to adjusted TV receiver 10 while being switched to pick up the screen by black-and-white TV camera 11. Then, times corresponding to the available picture area and size marker positions in picked-up output waveforms are measured by 16 to operate the time difference corresponding to the distance in 17, and the difference signal is outputted to detect the screen position by 20. Then, the difference signal is used to drive screen position adjustment mechanism 18 of receiver 10, thereby controlling so that the difference signal may be zero. |
