分析式白平衡仪的原理与实现

Theory and Reality of Analytical White Balance Tester

研制了一种新型的可直接在线使用的白平衡仪．它可通过颜色传感器采集屏幕发出的光中的红、绿、蓝信号，并与预先存储在仪器内的信号相比较，之后用模拟ＬＥＤ光带显示两者之差值或用数字方式显示亮度、色坐标、ＪＮＤ（刚辨差）和相关色温．仪器内部的信号发生器可根据参考白场的亮度值自动调整屏幕的亮度．仪器采用１６位的单片计算机处理测量值并控制电视信号发生器的输出电平．

The white balance tester is an instrument that adjusts the white balance for color TVs and displays. A new white balance tester for use directly at the production line has been designed.It picks up the R(Red),G(Green),and B(Blue)signals for the screen using color sensors, compares the signals with the data proviously stored in the internal memory, displays their differences with LED bars in the compare mode or displays x y Y,u v Y,JND(just noticeable difference) as well as correlated color temperature in the numerical mode. A built-in TV signal generator sets the luminance of the adjusting screen to the brightness of the reference white screen automatically. A 16-bit signal chip microcomputer processes the measured values and controls the output levels of the TV signal generator.