SILICA-MODIFIED-FLUORIDE BROAD ANGLE ANTI-REFLECTION COATINGS

摘要

The disclosure is directed to a coating consisting of a binary metal fluoride coating consisting a high refractive index metal fluoride layer on top of a substrate, a low refractive index metal fluoride layer on top of the high refractive index layer and layer of SiO2 or F-SiO2 containing 0.2 wt % to 4.5 (2000 ppm to 45,000 ppm) F on top of the low refractive index layer. In one embodiment the F content of F-SiO2 is in the range of 5000 ppm to 10,000 ppm F. The high index and low index materials are each deposited to a thickness of less than or equal to 0.9 quarter wave, and the capping material is deposited to a thickness in the range of 5 nm to 25 nm. The disclosure is also directed to optical elements having the foregoing coating and a method of making the coating.