20mm zinc selenide ZnSe s focusing lens, focal length specification 50.8/ 63.5/101.6mm, applicable power 50-100W. High light transmittance and high temperature resistance: The lens is made of PVD coded zinc(ZnSe) material with low s transmission loss, low absorption, strong light transmittance, and light transmittance can be as high as 99.8%, and can withstand high-power s.
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