Patent ID: 11959164
Assignee: nan
Field: Surface technology, coating (Chemistry)
Classification: CPC C | IPC C

Claim 0:
1. A method of forming a laser damage resistant and reliable broad band anti-reflective optical coating for high power mid-IR laser components at 8.9 MW/cm2 comprising the steps of:
a) providing a heavy metal fluoride glass fiber consisting of InF, ZrF4, or ZBLAN as a substrate in the mid-IR wavelength range of 1.5 to 5.5 μm;
b) depositing a broad band anti-reflective optical coating consisting of a low refractive index fluoride layer having n<1.5 and a high refractive index oxide layer having n>1.5 by a physical vapor deposition process onto said heavy metal fluoride glass fiber; and
c) depositing an Al2O3 encapsulation layer having a thickness less than 50 nm onto said optical coating layers, wherein said Al2O3 encapsulation layer is deposited by atomic layer deposition at a temperature between 60-100° C. using TMA and an oxidant.