Lode country assume silllike - similar silllike , and the next big anastigmatic , ground and west branch river set strench are consistent . it suffer the gravel silica rock , arena silica control . a handful of lode country or main lode country byway little orebody assume vein , or have the characteristic of balk reappear , compound of branch . these manifest the obvious characteristic of ore construct control 矿体以层?似层状产出为主，其次为大的透镜状，地表延伸与西岔河组地层一致。受砾屑硅质岩、含砾砂屑硅质岩控制。少数矿体或主矿体旁侧小矿体呈脉状、或具尖灭再现、分支复合特征。
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4 , single focuse the single head : is single for single laser head that panasonic lead off to adopt to focuse the double the laser beam for focusing ordering the project , he adopting the special whole synthesizing lens , passing lens in the center part ofly the focusing of formation cd the point , and pass the anastigmatic laser beam of part edge the formation the focusing of dvd the point , this kind of construction because of have no the machining to spread to move , and also can t produce the mechanical trouble , therefore increased to recognize the dish the speed , and however and also lowered the cost . but adoption this project of generation is with part of the next generation dvd nonsupports cdr 4单聚焦单镜头：为panasonic率先采用的单激光头单聚焦镜双聚焦点方案，他采用特别的全息综合透镜，通过透镜中间部分的激光束形成cd的聚焦点，通过透镜边缘部分的激光束形成dvd的聚焦点，这种结构由于没有机械传动，也不会产生机械故障，所以提高了认盘速度，不过同时也降低了成本。但采用此方案的第一代和部分第二代dvd不支持cdr 。
