Features: Coating 5 layers of gold film on silicon, more durable. Reflectivity is as high as 99%, and the power loss is small. Good optical thermal properties and fast heat dissipation. For laser engraving or cutting machine with power above 100w. Specifications: Material: Silicon Gold plating layer Wavelength: 10.6 um (10600 nm) Diameter: 19.05/20/25/30/38.1mm Diameter Tolerance: 0/-0.13mm Thickness: Thickness 3mm Thickness tolerance: ±0.25mm Centration: <3 arc minutes Clear aperture: >90% Surface Figure: <λ/2 per 1‘’ Dia Surface Quality: 40-20 scratch and dig AR/AR coating: R<0.5% per surface
