CLARIFYING COATING Russian patent published in 1997 - IPC

FIELD: optical instrumentation engineering. SUBSTANCE: clarifying coating is designated П K1 H K2 B, where П is substrate with refractive index of 2.2- 4.0; H is quarter-wave layer at working wave length made of fluorides with low refractive index; B is quarter-wave layer with high refractive index made of zinc sulfide or zinc selenide; K1 and K2 are multipliers of less than unit. Adhesive layer of zinc sulfide or zinc selenide with optical thickness of (0,1-0,2)λ/4, is introduced between substrate and coating. Layer of low refractive index is made of bismuth fluoride. EFFECT: more effective coating. 2 cl, 1 dwg, 1 tbl