Kawai S, Kohga Y
Appl Opt. 1992 Oct 10;31(29):6193-9. doi: 10.1364/AO.31.006193.
Modified signed-digit (MSD) numbers offer convenient parallel addition and subtraction of bits. The parallel addition of any two MSD numbers, no matter what the values of their bits may be, requires only three bit-pattern transformations. To perform such transformations optically, however, MSD data must be represented in a form suitable for cascade connection. Proposed here is a new cascade-connective MSD optical processor. Adding principles are successfully demonstrated by using an optical threshold device array in addition to new computer-generated holograms that are adjusted to equalize the intensity of their diffracted light beams.
修正符号数（MSD）提供了方便的位并行加法和减法。任何两个MSD数的并行加法，无论其位的值如何，仅需要三种位模式变换。然而，为了以光学方式执行这种变换，MSD数据必须以适合级联连接的形式表示。这里提出了一种新的级联连接MSD光学处理器。除了使用新的计算机生成全息图来调整其衍射光束的强度以使其相等之外，还通过使用光学阈值器件阵列成功演示了加法原理。
