For preparing high efficiency MgF2 antireflection coatings, the thickness and uniformity control of the MgF2 film evaporated by thermal resistance and electron beam were studied. On the basis of principles of antirc flection coatings and vacuum evaporation, many factors such as the weight and physical form of raw materials and the distance between evaporation source and substrates were carefully studied. The results show that for the raw materials in small particles or with low melting point, thermal resistance evaporation can not only control more easily but also avoid the raw material pollution comparing with electron beam evaporation; the actual weight of the evaporated raw materials is approximately linear to the film thickness;although the actual weight is equal, the thickness of film evaporated from the raw materials in polycrystalline particles form is higher than that in powder form; the thickness and uniformity of the film are higher for the substrates in the censer than those in the side of the rotating disk. At last, these experimental results are well explained by the evaporation model of the small plane source for rotating spherical fixture.%基于光学增透膜与真空蒸发镀膜的基本原理,从MgF2原料状态、原料蒸镀质量、蒸发源与基片间距等方面,研究了热电阻和电子束蒸镀的MgF2薄膜厚度与其均匀性的控制工艺,以制备出高效的MgF2增透膜.结果表明:对于颗粒度较小或熔点较低的原料,热电阻比电子束蒸镀更易控制,并可避免原料污染；原料实际蒸镀质量与膜厚呈较好的线性关系；实际蒸镀质量相同的多晶颗粒与粉末状原料相比,前者蒸镀膜更厚；基片置于旋转工转盘中心比其侧部区域蒸镀膜更厚、均匀性更好.最后利用旋转球面夹具的小平面源蒸发模型很好地解释了上述实验结果.
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