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氟化钙晶体是典型的萤石型结构，面心立方格子。钙离子分布于晶胞的顶点与面中心，如果把晶胞分为八个小立方体，则在每个立方体的中心均有氟离子占据，每一个钙离子由八个相等的最近的氟离子所包围。氟离子位于以钙离子为中心的立方体的角上，氟由四个相等的钙离子形成的四面体所包围。晶体沿（１１１）面解理，其光学性能为各向同性，与光学加工有关的性能是机械与物化性能。在加工窗口、透镜的实际工作中，发现在原料毛坯的切割中，如果切割面与解理面相交角度很大时，则很容易开裂破损。同样的问题也发生在粗磨和抛光工序上。当解理面与工件的光学面交角很小或平行时，不易出现开裂现象；相反，当解理面与工件光学交角很大以致接近９０°时，就容易出现裂现象。甚至很小的压力和温度变化都会引起破坏性效果。因此在加工晶体工件时，要格外注意解理面方向与光学面的夹角，并适时注意控制温度和力度，逐渐摸索出规律。与解理面不同夹角的光学面的加工，其夹角大小还影响所加工的光学面的光洁度、平面度等参数。结合工作实践针对晶体切割与晶向、元件形状、尺寸与晶向、温度等方面的影响，尤其是元件表面加工中的物化过程，需要以实践为基础，进行进一步的总结和认识。在此基础上，ＣａＦ２晶体的表面?
Calcium fluoride crystal is a typical fluorite structure, face-centered cubic lattice. Calcium ions are distributed at the apex and the center of the unit cell. If the unit cell is divided into eight small cubes, fluoride ions are occupied in the center of each of the cubes, and each calcium ion consists of eight equal nearest fluoride ion sites Surrounded. Fluoride ions are located on the corners of a cubic center centered on calcium ions surrounded by tetrahedrons formed by four equal calcium ions. Crystal along the (111) surface cleavage, the optical properties of isotropy, and optical processing-related performance is mechanical and physicochemical properties. In the processing window, the actual work of the lens, found in the cutting of raw material blank, if the cutting plane and cleavage plane intersection angle is very large, it is easy to crack cracking. The same problem occurs with roughing and polishing operations. When the cleavage plane and the workpiece optical surface angle is small or parallel, the phenomenon is not easy to crack; the other hand, when the cleavage plane and the workpiece optical angle is so great that close to 90 °, it is prone to cracking phenomenon. Even small changes in pressure and temperature can cause destructive effects. Therefore, when processing crystal workpieces, pay special attention to the angle between the cleavage plane direction and the optical surface, and timely pay attention to controlling the temperature and force, and gradually find out the law. Different from the cleaved surface of the optical surface processing, the angle of the size of the optical surface also affects the processing of the finish, flatness and other parameters. Combined with the practice of practice, the influence of crystal cutting and crystal orientation, shape, size and orientation of crystal, temperature and so on, especially the physical and chemical processes in the surface processing of components, needs to be further summarized and recognized based on practice. On this basis, the surface of CaF2 crystals?