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本文介绍了一种标准图像信号发生器的原理、结构和特点。该发生器采用先进的数字合成技术，融合了ＥＰＬＤ编程技术、ＥＰＲＯＭ技术和高速、高精度１２ｂｉｔＤ／Ａ转换器，配以高性能视频放大和高阶模拟低通滤波器，产生的信号波形失真小、信噪比高。可生成正弦波、方波、三角波、线性波及直流等多种标准图像信号。并介绍了将该系统应用于图像板性能评价的具体方法。实际分析了一种图像板的时域和频域特性，主要包括线性度、Ａ／Ｄ转换精度和调制传递函数等。给出了被测图像板的调制传递函数曲线
This article describes the principle, structure and characteristics of a standard image signal generator. The generator uses advanced digital synthesis technology, a combination of EPLD programming technology, EPROM technology and high-speed, high-precision 12bitD / A converter, together with high-performance video amplification and high-end analog low-pass filter, the resulting signal distortion is small , High signal to noise ratio. Can generate sine wave, square wave, triangle wave, linear wave and DC and other standard image signal. The method of applying this system to the performance evaluation of image board is introduced. The time and frequency domain characteristics of an image plate are analyzed, including linearity, A / D conversion accuracy and modulation transfer function. The curve of modulation transfer function of the tested image board is given