Title:
OPTICAL FILTER AND IMAGING APPARATUS
Document Type and Number:
Japanese Patent JP2021140177
Kind Code:
A
Abstract:
To provide an optical filter that inhibits incident angle dependency of spectral transmittance, less absorbing light in a visible region, and exhibiting high transmittance, and an imaging apparatus including the optical filter and excellent in color reproducibility.SOLUTION: The optical filter comprises: an absorber layer including a near-infrared absorption agent containing specifically structured squarylium-based compound, having absorption maximum wavelength in wavelength 660 to 750 nm, in which transmittance is 10 to 40% at absorption maximum wavelength, 80% or more at wavelength 600 nm, and 55% or more at wavelength 650 nm, and a difference between wavelength between wavelength 650 nm and the absorption maximum wavelength and wavelength between the absorption maximum wavelength and wavelength 1150 nm where the transmittance is 50% falls within 50 nm; and a reflective layer composed of a dielectric multilayer in which wavelength transmittance of which is 5% or less in wavelength 720 to 1150 nm and transmittance of which is 50% in wavelength 680 to 750 nm has a certain relation with a specific wavelength of the absorber layer, and wavelength difference of light having transmittance 50% at incidence angles 30° and 0° in wavelength 680 to 750 nm is 25 nm or less.SELECTED DRAWING: Figure 5A
Inventors:
OI YOSHIHARU
Application Number:
JP2021082503A
Publication Date:
September 16, 2021
Filing Date:
May 14, 2021
Export Citation:
Assignee:
AGC INC
International Classes:
G02B5/22; C09B57/00; C09B67/20; G02B5/28; H01L27/146
Foreign References:
| WO2017094672A1 | 2017-06-08 | |||
| WO2015099060A1 | 2015-07-02 | |||
| WO2013015303A1 | 2013-01-31 | |||
| WO2016114363A1 | 2016-07-21 |
Attorney, Agent or Firm:
Patent business corporation glory patent office