US 12,147,065 B2
Optical filter
Kazuhiko Shiono, Fukushima (JP); Takeru Wakabayashi, Tokyo (JP); and Takashi Nagata, Shizuoka (JP)
Assigned to AGC Inc., Tokyo (JP)
Filed by AGC Inc., Tokyo (JP)
Filed on Dec. 27, 2023, as Appl. No. 18/397,360.
Application 18/397,360 is a continuation of application No. PCT/JP2022/026339, filed on Jun. 30, 2022.
Claims priority of application No. 2021-113059 (JP), filed on Jul. 7, 2021.
Prior Publication US 2024/0142681 A1, May 2, 2024
Int. Cl. G02B 5/20 (2006.01)
CPC G02B 5/208 (2013.01) 12 Claims
OG exemplary drawing
 
1. An optical filter, comprising:
a substrate,
a dielectric multilayer film 1 laid on or above one major surface of the substrate, and
a dielectric multilayer film 2 laid on or above the other major surface of the substrate, wherein
the substrate comprises a near infrared ray absorbing glass and a resin film,
the resin film has a thickness of 10 μm or less,
the resin film comprises a resin and a pigment (NIR1), and
the optical filter satisfies all of the following spectral characteristics (i-1) to (i-5), (i-7) to (i-10), (i-12), (i-14), and (i-19):
(i-1) in a spectral transmittance curve at an incident angle of 0 degrees, an average transmittance T450-600(0deg)AVE at a wavelength of 450 nm to 600 nm is 85% or more,
(i-2) in the spectral transmittance curve at an incident angle of 0 degrees, a maximum transmittance T450-600(0deg)MAX at the wavelength of 450 nm to 600 nm is 90% or more,
(i-3) an absolute value of a difference between the average transmittance T450-600(0deg)AVE and an average transmittance T450-600(50deg)AVE at the wavelength of 450 nm to 600 nm in a spectral transmittance curve at an incident angle of 50 degrees is 5% or less,
(i-4) in the spectral transmittance curve at an incident angle of 0 degrees, a transmittance T450(0deg) at a wavelength of 450 nm is 80% or more,
(i-5) in the spectral transmittance curve at an incident angle of 0 degrees, a wavelength IR50(0deg) at which a transmittance is 50% is in a range of 610 nm to 650 nm,
(i-7) in the spectral transmittance curve at an incident angle of 0 degrees, an average transmittance T700-1000(0deg)AVE at a wavelength of 700 nm to 1,000 nm is 2% or less,
(i-8) in the spectral transmittance curve at an incident angle of 50 degrees, an average transmittance T700-1000(50deg)AVE at the wavelength of 700 nm to 1,000 nm is 2% or less,
(i-9) in the spectral transmittance curve at an incident angle of 0 degrees, an average transmittance T1000-1200(0deg)AVE at a wavelength of 1,000 nm to 1,200 nm is 5% or less,
(i-10) in the spectral transmittance curve at an incident angle of 50 degrees, an average transmittance T1000-1200(50deg)AVE at the wavelength of 1,000 nm to 1,200 nm is 5% or less,
(i-12) when the dielectric multilayer film 1 side is the incident direction, a maximum reflectance R1600-1200(5deg)MAX at a wavelength of 600 nm to 1,200 nm is 45% or less in the spectral reflectance curve at an incident angle of 5 degrees,
(i-14) when the dielectric multilayer film 2 side is the incident direction, a maximum reflectance R2600-1200(5deg)MAX at the wavelength of 600 nm to 1,200 nm is 45% or less in the spectral reflectance curve at an incident angle of 5 degrees, and
(i-19) the transmittance T450(0deg)/a maximum transmittance T1000-1200(0deg)MAX≥20, where the transmittance T450(0deg) is a transmittance at the wavelength of 450 nm and the maximum transmittance T1000-1200(0deg)MAX is a maximum transmittance at the wavelength of 1,000 nm to 1,200 nm in the spectral transmittance curve at an incident angle of 0 degrees.