A practical system for measuring a film thickness based on laser interferometry has been constructed using laminar-like laser and a CCD camera. The system can measure a film thickness at a measuring frequency of 50 Hz, which enables real-time measurement in practical use. The measurable minimum thickness by means of a blue laser having a wavelength of 405 nm was 2.4 μm, and the maximum thickness was 1.2 mm for a film with a refractive index of 1.4. The measurement error of the film thickness due to the spherical aberration of the cylindrical lens was Δh/h=2% at maximum, where h expresses film thickness and Δh its error amount.
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机译：已经使用层状激光器和CCD照相机构造了基于激光干涉法测量膜厚的实用系统。该系统可以以50 Hz的测量频率测量薄膜厚度，从而可以在实际使用中进行实时测量。借助于波长为405 nm的蓝色激光测得的最小厚度为2.4μm，对于折射率为1.4的薄膜，最大厚度为1.2 mm。由柱面透镜的球差引起的膜厚的测量误差最大为Δh/ h ＝ 2％，其中h表示膜厚，Δh表示其误差量。
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