Antireflection film and optical device
US9310525B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 29, 2012 |
| Grant date | Apr 12, 2016 |
| Priority date | — |
| Expiry date | Jan 31, 2035 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/24942
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An object of the present invention is to provide an antireflection film and an optical device having excellent antireflection characteristics against a light beam having a wide wavelength range at a wide range of an incident angle, and also having practically sufficient durability. To achieve the above object, the present invention adopts an antireflection film having an optical two-layer structure composed of an intermediate layer provided on a base material and a low refractive index layer provided on a surface of the intermediate layer, wherein the low refractive index layer is a layer obtained by binding hollow silica by a binder, a refractive index n(1) thereof is between 1.15 and 1.24 inclusive, and a refractive index n(2) of the intermediate layer satisfies a relation in the expression (1) below assuming a refractive index of the base material n(sub).n(1)×√{square root over (n(sub))}×0.930≦n(2)≦n(1)×√{square root over (n(sub))}×0.985 (1).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.