Near-infrared cut filter
US10495796B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 21, 2018 |
| Grant date | Dec 3, 2019 |
| Priority date | — |
| Expiry date | Aug 21, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02B5/223
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
There is provided a near-infrared cut filter which has a visible light transmitting property and a near-infrared shielding property both at high levels by that its transmission spectrum has a steep inclination in the vicinity of the boundary between the visible light and the near-infrared, and which can also be sufficiently reduced in size and thickness. The near-infrared cut filter has a near-infrared absorbing layer which contains a near-infrared absorbing dye containing at least one dye in which a condensed ring structure containing at least a benzene ring and a ring having nitrogen atom is bonded to both sides of a squarylium skeleton and which have a carboxylic acid amide structure at a second position of the benzene ring (where the carboxylic acid has a substituent having 5 to 25 having one or more branches), and a transparent resin with a refractive index of 1.45 or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.