Anti-reflective film and optical element having anti-reflective film
US7301695B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 9, 2005 |
| Grant date | Nov 27, 2007 |
| Priority date | — |
| Expiry date | Apr 19, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B1/115
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In an anti-reflective film including alternating layers of high refractive-index layers and low refractive-index layers, by designing such that a designed central wavelength λ0 is within a wavelength range of 141 nm to 189 nm, and that when the first to eighth layers as counted from a substrate have optical film thicknesses d1 to d8 respectively, the equations of:0.45λ0≦d1≦0.65λ0;0.05λ0≦d2≦0.20λ0;0.29λ0≦d3≦0.49λ0;0.01λ0≦d4≦0.15λ0;0.05λ0≦d5≦0.20λ0;0.23λ0≦d6≦0.28λ0;0.23λ0≦d7≦0.28λ0; and0.23λ0≦d8≦0.28λ0are satisfied, the anti-reflective film can be formed so as to have a low reflectance for a light incident at such a large angle as 30 degrees or more, without increasing the whole thickness of the film.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.