Optical measurement plane is a glass plane with minimal errors in surface roughness and flatness, which will produce optical interference fringes (see laser length measurement technology). The flat crystal is made of optical glass or timely glass. Commonly used flat crystals include flat flat crystals, long flat crystals and parallel flat crystals.
Plane flat crystal is used to measure the flatness error of a highly smooth surface. Figure 1a shows the flatness error of a surface measured with a plane flat crystal inspection gauge. The diameter of cylindrical flat crystal is usually 45 ~ 1 50 mm. The flatness error of optical measurement plane is1and the accuracy is 0.03 ~ 0.05 micron. The second-order accuracy is 0. 1 micron. The effective length of an ordinary rectangular flat crystal is generally 200mm.
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use
Plane flat crystal is a common tool for measuring block gauges by interference method, which is used to check the grinding and flatness of block gauges, gauges, sealing surfaces of parts, measuring instruments and measuring tools.
It is suitable for on-site inspection of optical processing plants, measuring rooms of factories and mines, precision processing workshops and valve sealing surfaces, and is also suitable for flatness inspection of universities and scientific research units.
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