三值光学计算机解码器的理论、技术和实现

经过十余年发展，三值光学计算机系统的解码器已经形成了一个比较完整的理论．本文从解码器的实践中抽象出三值光学计算机解码器的理论结构，并介绍地址标定、阈值设定、偏色纠正、坏点剔除和目标画面判断等关键技术的要点，阐明了这些技术的内在联系．通过对实用解码器的描述，介绍了从解码器的理论结构到实用结构的合理简化和各项技术的实现方案，以及解码器的工作流程．

Theory, technology and progress of a ternary optical computer＇s decoder

In a ternary optical computer （TOC）, the function of the decoder is to transform three-state opmcal signal output by the ternary optical processor into two-state electoral signals that can be used in an electronic computer. The coder has the inverse function. Together, the coder and decoder form a bridge for exchanging data between the TOC and an electronic computer. In the past decade, much research has focused on these two components in a TOC. As it has a simple structure, a favorable coder was manufactured in 2007. How- ever, the complex mechanism of the decoder has improved more slowly. With the invention of the SD11, the third experimental TOC system for application research, most problems in the decoder were solved, new tech- nologies were realized, and a theoretically better framework was introduced. In this paper we discuss these advancements in the TOC decoder. First, an ideal decoder structure abstracted from practice is shown in Figure 1. Next a suitable actual decoder comprising two camera modules and an embedded computer is il- lustrated in Figure 2. This is a simplification of the ideal structure and is used in the SDll. Thereafter, we describe the actual decoder＇ s workfiow, as depicted in Figure 3. Finally tile use of and experiments with five key decoder techniques are discussed. The five techniques are address calibration, threshold setting, color cor- rection, bad-pixels-out, and target picture judgment. Address calibration ascertains the memory address in the decode buffer for the data of every pixel in the target picture. The threshold setting ensures that each pixel＇ s w~lue is 1 when the pixel is brighter than the upper threshold and 0 when the pixel is darker than the lower tilreshold. Color correction removes the harmful effect from ambient light and the color cast of liquid crystal and Polaroid. Bad-pixels-out enforces substitutes for no-work pixels with spare work pixels, while target picture judgment accomplishes synchronization between the optical processor and decoder.