Sapphireoptical crystalsSingle crystal sapphirehas a unique combination of physical, chemical and optical properties allowing it to withstand high temperatures, high pressure, thermal shock, and water or sand erosion. It is chemically inert, with a low friction coefficient, and excellent electrical, optical, and dielectric characteristics. In addition, its radiation resistance makes it an excellent material for use in optical windows for space applications.SpecificationPolishing Specification for Optical GradeⅠOrientation Tolerence< 1°Thickness/Diameter Tolerance±0.10 mmSurface Flatness<(λ-2λ)@632nmWavefront Distortion<(2-4)λ@632nmSurface Quality80/50Parallel10ˊPerpendicular60ˊClear Aperture>90%Chammfer<0.2×45°Polishing Specification for Optical Grade ⅡOrientation Tolerence< 0.5°Thickness/Diameter Tolerance±0.10 mmSurface Flatness<(λ/2-λ/4)@632nmWavefront Distortion<(1-2)λ@632nmSurface Quality60/40Parallel1ˊPerpendicular30ˊClear Aperture>90%Chammfer<0.2×45°Polishing Specification for Optical Grade ⅢOrientation Tolerence< 0.2°Thickness/Diameter Tolerance±0.02 mmSurface Flatness(λ/4-λ/6)@632nmWavefront Distortion<(λ-λ/2)@632nmSurface Quality40/20Parallel45〞Perpendicular20ˊClear Aperture>90%Chammfer<0.2×45°
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