计算全息半色调编码技术的研究 - 天津大学期刊中心.PDF

36 1 　　　　　 Vol.36　No.1 　　200　3 1 Journal ofTianjin University Jan.2003 　 1, 2 2 1 董艇舰 , 吴玉侠, 王太勇 (1., 300072;2., 300191) 　:论述了计算全息的基本原理及常用的编码方法, 在罗曼型和博奇型编码的基础上, 运用空间 冲调制技 术, 提出了新型的编码技术———半色调位相型和标准型编码.半色调型编码用圆形通光孔代替矩形 孔, 以圆孔面积 及位置来记录全息信息, 改变了输出模式, 减少了编码参数, 为全息图的后期制作提供了一种新的方法.同时通过 理论计算和结果分析证明了半色调位相型编码具有和罗曼型同样好的衍射效率, 半色调标准型编码具有和博奇型 一样大的带宽, 但它们的图形数据减少一半. :;; :TP399　　　:A　　　:0493-2137(2003)01-0041-04 Study of Half-Tone Coding Technology 1, 2 2 1 DONG Ting-jian , WU Yu-xia , WANGTai-yong (1.School of echanical Engineering, Tianjin University, Tianjin 300072, China; 2.Tianjin Instituteof Technology, Tianjin 300191, China) Abstract:In the paper, the fundamental principle and common coding technique of computer-generated hologram (CGH)are discussed.Based on coding of LohmannandBurch, anew type coding thehalf-tonephase code and half- tone standard code are put forward by using the spacepulsemodulation technique.Thehalf-tone codeuses structure parameter of circular-hole insteadof rectanglehole and records thehologram information by area and positionof circu- lar-hole, so itchangesthe outputmodel, reduces theparameter andoffersa new kindof method formakinghologram inlater stage. eanwhile, by calculation and analysis, this paper proves that the diffraction efficiency of half-tone phase codeis as high as Lohmann and thebandwidth of half-tone standard codeis as large as Burch, but thegraph data of half-tone code areonly half of them. Keywords:computer-generated hologram(CGH);coding;half-tone 　　、