Optical Filters

Abstract

The present invention is an optical filter comprising a substrate and a dielectric multilayer film layered as an outermost layer on at least one main surface of the substrate, wherein the substrate has a resin film including a pigment (IR) and a resin, the pigment (IR) has a maximal absorption wavelength of 680-800 nm in the resin, and the optical filter satisfies all of specific spectral characteristics (i-1) through (i-23) in a spectral transmittance curve at incidence angles of 0 degrees, 30 degrees, and 70 degrees.

Description

[Technical Field]

[0001] The present invention relates to an optical filter that transmits light in the visible wavelength region and blocks light in the near-infrared wavelength region. [Background technology]

[0002] In order to reproduce color tones well and obtain clear images, imaging devices using solid-state imaging elements use optical filters that transmit light in the visible range (hereinafter also referred to as "visible light") and block light in the ultraviolet wavelength range (hereinafter also referred to as "ultraviolet light") and light in the near-infrared wavelength range (hereinafter also referred to as "near-infrared light").

[0003] Such optical filters can be made in various ways, for example, by laminating dielectric thin films with different refractive indices alternately on one or both sides of a transparent substrate (dielectric multilayer film), and using optical interference to reflect light that needs to be blocked, such as a reflective filter.

[0004] Optical filters with dielectric multilayer films have problems such as changes in the spectral transmittance curve depending on the angle of incidence because the optical thickness of the dielectric multilayer film changes depending on the angle of incidence, light leakage due to high transmittance of near-infrared light that should have high reflectance at high angles of incidence, and noise generation due to near-infrared light reflected by the dielectric multilayer film. The use of such filters can potentially affect the spectral sensitivity of solid-state imaging devices. In particular, with the recent trend toward thinner camera modules, use under high angles of incidence is expected.

[0005] Here, since the sensitivity of the image sensor mounted on the imaging device is greatest in the range of around 700 to 850 nm, there was a need for an optical filter that could block this near-infrared light region even at high angles of incidence without substantially affecting the transmittance of visible light.

[0006] Patent Document 1 describes an optical filter that can achieve high levels of both color shading suppression and ghost suppression in camera images, and that uses a substrate that has a sufficiently strong absorption band around a wavelength of 700 nm and a wide absorption band in the near-infrared wavelength region of 900 nm or more. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] International Publication No. 2018 / 043564 Summary of the Invention [Problem to be solved by the invention]

[0008] However, the optical filter described in Patent Document 1 has reduced transmittance in the visible light region due to the use of a near-infrared absorbing dye whose maximum absorption wavelength is 800 nm or longer.

[0009] Therefore, an object of the present invention is to provide an optical filter that has high transmittance for visible light and high blocking ability for near-infrared light of 700 nm or more, and that suppresses a decrease in blocking ability at high angles of incidence of near-infrared light of 700 nm or more. [Means for solving the problem]

[0010] The present invention provides an optical filter having the following configuration. [1] An optical filter comprising a substrate and a dielectric multilayer film laminated as an outermost layer on at least one main surface side of the substrate, the substrate has a resin film containing a dye (IR) and a resin, the dye (IR) has a maximum absorption wavelength in the resin at 680 to 800 nm, The optical filter satisfies all of the following spectral characteristics (i-1) to (i-23). Spectral characteristics (i-1)~(i-9) in the spectral transmittance curve at an incident angle of 0 degrees: (i-1) Average transmittance T at wavelengths of 440 to 490 nm 440-490(0deg)AVE Over 85% (i-2) Average transmittance T at wavelengths of 490 to 560 nm 490-560(0deg)AVE Over 90% (i-3) Average transmittance T at wavelengths of 560 to 590 nm560-590(0deg)AVE Over 83% (i-4) Wavelength IR50 at which transmittance is 50% (0deg) is in the range of 600-680 nm (i-5) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(0deg)MAX is less than 2% (i-6) Transmittance T at a wavelength of 750 nm 750(0deg) is 0.5% or less (i-7) Maximum transmittance T at wavelengths of 760 to 800 nm 760-800(0deg)MAX is less than 1% (i-8) Maximum transmittance T at wavelengths of 800 to 900 nm 800-900(0deg)MAX is less than 1% (i-9) Maximum transmittance T at wavelengths of 900 to 1100 nm 900-1100(0deg)MAX is less than 1% Spectral characteristics (i-10)~(i-18) of the spectral transmittance curve at an incident angle of 30 degrees: (i-10) Average transmittance T at wavelengths of 440 to 490 nm 440-490(30deg)AVE Over 84% (i-11) Average transmittance T at wavelengths of 490 to 560 nm 490-560(30deg)AVE Over 90% (i-12) Average transmittance T at wavelengths of 560 to 590 nm 560-590(30deg)AVE Over 83% (i-13) Wavelength IR50 at which transmittance is 50% (30deg) is in the range of 600-680 nm (i-14) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(30deg)MAX is less than 2% (i-15) Transmittance T at a wavelength of 750 nm 750(30deg) is 0.5% or less (i-16) Maximum transmittance T at wavelengths of 760 to 800 nm 760-800(30deg)MAX is less than 1% (i-17) Maximum transmittance T at wavelengths of 800 to 900 nm 800-900(30deg)MAX is less than 1% (i-18) Maximum transmittance T at wavelengths of 900 to 1100 nm 900-1100(30deg)MAX is less than 5% (i-19) The wavelength IR50 (0deg) and the wavelength IR50(30deg) The absolute difference is 8nm or less Spectral characteristics (i-20)~(i-23) of the spectral transmittance curve at an incident angle of 70 degrees: (i-20) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(70deg)MAX is 1.5% or less (i-21) Transmittance T at a wavelength of 750 nm 750(70deg) is 1.5% or less (i-22) Maximum transmittance T at wavelengths of 760 to 800 nm 760-800(70deg)MAX is 1.5% or less (i-23) Maximum transmittance T at wavelengths of 800 to 900 nm 800-900(70deg)MAX is 1.5% or less [Effects of the Invention]

[0011] According to the present invention, an optical filter can be provided that has high transmittance for visible light and high blocking ability for near-infrared light of 700 nm or more, and that suppresses a decrease in blocking ability at high angles of incidence for near-infrared light of 700 nm or more. [Brief explanation of the drawings]

[0012] [Figure 1] FIG. 1 is a cross-sectional view schematically illustrating an example of an optical filter according to an embodiment. [Figure 2] FIG. 2 is a cross-sectional view schematically showing another example of the optical filter according to the embodiment. [Figure 3] FIG. 3 is a cross-sectional view schematically showing another example of the optical filter according to the embodiment. [Figure 4] FIG. 4 is a cross-sectional view schematically showing another example of the optical filter according to the embodiment. [Figure 5] FIG. 5 is a diagram showing the spectral transmittance curve of the dielectric multilayer film 1 of Example 2-1. [Figure 6] FIG. 6 is a diagram showing the spectral transmittance curve of the dielectric multilayer film 2 of Example 2-2. [Figure 7] FIG. 7 is a diagram showing the spectral transmittance curve of the optical filter of Example 3-11. [Figure 8] FIG. 8 is a diagram showing the spectral transmittance curve of the optical filter of Example 3-13. DETAILED DESCRIPTION OF THE INVENTION

[0013] Hereinafter, an embodiment of the present invention will be described. In this specification, the near-infrared absorbing dye may be abbreviated as "NIR dye" and the ultraviolet absorbing dye may be abbreviated as "UV dye". In this specification, a compound represented by formula (I) is referred to as compound (I). The same applies to compounds represented by other formulas. A dye consisting of compound (I) is also referred to as dye (I), and the same applies to other dyes. Furthermore, a group represented by formula (I) is also referred to as group (I), and the same applies to groups represented by other formulas.

[0014] In this specification, the internal transmittance is the transmittance obtained by subtracting the influence of interface reflection from the measured transmittance, as expressed by the formula {measured transmittance / (100-reflectance)}×100. In this specification, the transmittance of a substrate, the transmittance of a resin film including a case where a dye is contained in the resin, and the transmittance spectrum measured by dissolving a dye in a solvent such as dichloromethane are all "internal transmittance" even when they are referred to as "transmittance." On the other hand, the transmittance of an optical filter having a dielectric multilayer film is an actually measured transmittance.

[0015] In this specification, for example, a transmittance of 90% or more in a specific wavelength range means that the transmittance is not less than 90% across the entire wavelength range, i.e., the minimum transmittance is 90% or more across the wavelength range. Similarly, for example, a transmittance of 1% or less in a specific wavelength range means that the transmittance is not more than 1% across the entire wavelength range, i.e., the maximum transmittance is 1% or less across the wavelength range. The same applies to internal transmittance. The average transmittance and average internal transmittance in a specific wavelength range are the arithmetic mean of the transmittance and internal transmittance per 1 nm in the wavelength range. The optical properties can be measured using a UV-visible spectrophotometer. In this specification, the use of "to" to indicate a range of values ​​includes the upper and lower limits.

[0016] <Optical filters> An optical filter according to one embodiment of the present invention (hereinafter also referred to as "this filter") is an optical filter that includes a substrate and a dielectric multilayer film laminated as an outermost layer on at least one main surface side of the substrate, and that satisfies specific spectral characteristics described below. Here, the substrate has a resin film containing a dye (IR) that has a maximum absorption wavelength in the resin at 680 to 800 nm, and a resin. The dye (IR) is an NIR dye. By containing a dye that absorbs near-infrared rays in the substrate, the absorption characteristics of the substrate can suppress deterioration of the spectral characteristics of the dielectric multilayer film at high incident angles, such as the occurrence of light leakage and noise in the near-infrared region. Each dye and resin will be described later.

[0017] An example of the configuration of the present filter will be described with reference to the drawings. Figures 1 to 4 are cross-sectional views that schematically show an example of an optical filter according to an embodiment. 1 is an example in which a dielectric multilayer film 30 is provided on one main surface side of a substrate 10. Note that "having a specific layer on the main surface side of the substrate" does not only mean that the layer is provided in contact with the main surface of the substrate, but also includes a case in which another functional layer is provided between the substrate and the layer.

[0018] The optical filter 1B shown in FIG. 2 is an example in which the substrate 10 has a dielectric multilayer film 30 on both main surfaces thereof.

[0019] 3 is an example in which a substrate 10 has a support 11 and a resin film 12 laminated on one main surface of the support 11. The optical filter 1C further has a dielectric multilayer film 30 on the resin film 12 and on the main surface of the support 11 on which the resin film 12 is not laminated.

[0020] 4 is an example in which a substrate 10 has a support 11 and resin films 12 laminated on both main surfaces of the support 11. The optical filter 1D further has a dielectric multilayer film 30 on each of the resin films 12.

[0021] The optical filter of the present invention satisfies all of the following spectral characteristics (i-1) to (i-23).

[0022] Spectral characteristics (i-1)~(i-9) in the spectral transmittance curve at an incident angle of 0 degrees: (i-1) Average transmittance T at wavelengths of 440 to 490 nm 440-490(0deg)AVE Over 85% (i-2) Average transmittance T at wavelengths of 490 to 560 nm 490-560(0deg)AVE Over 90% (i-3) Average transmittance T at wavelengths of 560 to 590 nm 560-590(0deg)AVE Over 83% (i-4) Wavelength IR50 at which transmittance is 50% (0deg) is in the range of 600-680 nm (i-5) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(0deg)MAX is less than 2% (i-6) Transmittance T at a wavelength of 750 nm 750(0deg) is 0.5% or less (i-7) Maximum transmittance T at wavelengths of 760 to 800 nm 760-800(0deg)MAX is less than 1% (i-8) Maximum transmittance T at wavelengths of 800 to 900 nm 800-900(0deg)MAX is less than 1% (i-9) Maximum transmittance T at wavelengths of 900 to 1100 nm 900-1100(0deg)MAX is less than 1%

[0023] Spectral characteristics (i-10)~(i-18) of the spectral transmittance curve at an incident angle of 30 degrees: (i-10) Average transmittance T at wavelengths of 440 to 490 nm 440-490(30deg)AVE Over 84% (i-11) Average transmittance T at wavelengths of 490 to 560 nm 490-560(30deg)AVE Over 90% (i-12) Average transmittance T at wavelengths of 560 to 590 nm 560-590(30deg)AVE Over 83% (i-13) Wavelength IR50 at which transmittance is 50% (30deg) is in the range of 600-680 nm (i-14) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(30deg)MAX is less than 2% (i-15) Transmittance T at a wavelength of 750 nm 750(30deg)is 0.5% or less (i-16) Maximum transmittance T at wavelengths of 760 to 800 nm 760-800(30deg)MAX is less than 1% (i-17) Maximum transmittance T at wavelengths of 800 to 900 nm 800-900(30deg)MAX is less than 1% (i-18) Maximum transmittance T at wavelengths of 900 to 1100 nm 900-1100(30deg)MAX is 5% or less

[0024] (i-19) The wavelength IR50 (0deg) and the wavelength IR50 (30deg) The absolute difference is 8nm or less

[0025] Spectral characteristics (i-20)~(i-23) of the spectral transmittance curve at an incident angle of 70 degrees: (i-20) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(70deg)MAX is 1.5% or less (i-21) Transmittance T at a wavelength of 750 nm 750(70deg) is 1.5% or less (i-22) Maximum transmittance T at wavelengths of 760 to 800 nm 760-800(70deg)MAX is 1.5% or less (i-23) Maximum transmittance T at wavelengths of 800 to 900 nm 800-900(70deg)MAX is 1.5% or less

[0026] This filter, which satisfies all of the spectral characteristics (i-1) to (i-23), is an optical filter that has excellent visible light transmittance and near-infrared light blocking properties, and also suppresses the deterioration of near-infrared light blocking properties at a very high incident angle of 70 degrees.

[0027] The spectral characteristics (i-1) to (i-9) are the characteristics at an incident angle of 0 degrees. Satisfying the spectral characteristic (i-1) means that the transmittance in the blue light region of 440 to 490 nm is excellent. 440-490(0deg)AVE is preferably 87% or more, more preferably 87.5% or more.

[0028] Satisfying the spectral characteristic (i-2) means that the transmittance is excellent in the blue and green light range of 490 to 560 nm.490-560(0deg)AVE is preferably 92% or more, more preferably 93% or more.

[0029] Satisfying the spectral characteristic (i-3) means that the glass has excellent transmittance in the green and yellow light range of 560 to 590 nm. 560-590(0deg)AVE is preferably 84% or more, more preferably 86% or more.

[0030] By satisfying the spectral characteristics (i-4), it is possible to block the infrared band and efficiently capture visible light. (0deg) is preferably in the range of 610 to 670 nm, more preferably 620 to 660 nm.

[0031] Satisfying the spectral characteristics (i-5) means that the film has excellent blocking properties in the near-infrared light region of 700 to 760 nm. 700-760(0deg)MAX is preferably 0.7% or less, more preferably 0.5% or less.

[0032] Satisfying the spectral characteristics (i-6) means that the film has excellent blocking properties in the near-infrared region of 750 nm. 750(0deg) is preferably 0.4% or less, more preferably 0.2% or less.

[0033] Satisfying the spectral characteristics (i-7) to (i-9) means that the film is excellent in blocking light in the long wavelength region beyond near-infrared light of 760 to 1100 nm. T 760-800(0deg)MAX is preferably 0.8% or less, more preferably 0.7% or less. T 800-900(0deg)MAX is preferably 0.8% or less, more preferably 0.7% or less. T 900-1100(0deg)MAX is preferably 0.8% or less, more preferably 0.7% or less.

[0034] The spectral characteristics (i-10) to (i-18) are the characteristics at an incident angle of 30 degrees. By satisfying the spectral characteristics (i-10), it means that the transmittance in the blue light region of 440 to 490 nm is excellent even at high incident angles. 440-490(30deg)AVE is preferably 84.5% or more, more preferably 85% or more.

[0035] By satisfying the spectral characteristic (i-11), it means that the transmittance is excellent in the blue and green light region of 490 to 560 nm even at a high angle of incidence. 490-560(30deg)AVE is preferably 91% or more, more preferably 92% or more.

[0036] By satisfying the spectral characteristic (i-12), it means that the transmittance is excellent in the green and yellow light range of 560 to 590 nm even at high incident angles. 560-590(30deg)AVE is preferably 83.5% or more, more preferably 85.5% or more.

[0037] By satisfying the spectral characteristics (i-13), it is possible to block infrared light even at high angles of incidence and efficiently capture visible light. (30deg) is preferably in the range of 610 to 670 nm, more preferably 620 to 660 nm.

[0038] By satisfying the spectral characteristic (i-14), it means that the film has excellent blocking properties for the near-infrared light region of 700 to 760 nm even at high angles of incidence. 700-760(30deg)MAX is preferably 1.3% or less, more preferably 1.2% or less.

[0039] By satisfying the spectral characteristics (i-15), it means that the film has excellent blocking properties for the near-infrared light region of 750 nm even at high angles of incidence. 750(30deg) is preferably 0.4% or less, more preferably 0.3% or less.

[0040] Satisfying the spectral characteristics (i-16) to (i-18) means that the film is excellent in blocking long wavelengths beyond near-infrared light of 760 to 1100 nm even at high angles of incidence. T 760-800(30deg)MAXis preferably 0.5% or less, more preferably 0.4% or less. T 800-900(30deg)MAX is preferably 0.5% or less, more preferably 0.4% or less. T 900-1100(30deg)MAX is preferably 4.5% or less, more preferably 4% or less.

[0041] By satisfying the spectral characteristic (i-19), it is meant that there is little shift even at high angles of incidence in the near-infrared light absorption band of wavelengths from 600 to 680 nm, and color reproducibility is excellent. The spectral characteristic (i-19) is preferably 7 nm or less, and more preferably 6 nm or less.

[0042] The spectral characteristics (i-20) to (i-23) are the characteristics at an incident angle of 70 degrees.

[0043] By satisfying the spectral characteristics (i-20), it means that there is no light leakage even at very high angles of incidence, and it has excellent blocking properties in the near-infrared light region of 700 to 760 nm. 700-760(70deg)MAX is preferably 1.4% or less, more preferably 1.3% or less.

[0044] By satisfying the spectral characteristics (i-21), there is no light leakage even at very high angles of incidence, and the film has excellent blocking properties in the near-infrared region of 750 nm. 750(70deg) is preferably 0.7% or less, more preferably 0.6% or less.

[0045] By satisfying the spectral characteristics (i-22) to (i-23), there is no light leakage even at extremely high angles of incidence, and this means that the film has excellent blocking properties for the long wavelength region from near infrared light of 760 to 900 nm onwards. T 760-800(70deg)MAX is preferably 1% or less, more preferably 0.8% or less. T 800-900(70deg)MAX is preferably 1.4% or less, more preferably 1.3% or less.

[0046] The optical filter of the present invention preferably further contains a dye (U) having a maximum absorption wavelength in the resin at 370 to 430 nm, and further satisfies the following spectral characteristic (i-24). (i-24) The wavelength UV at which the transmittance is 50% in the spectral transmittance curve at a wavelength of 400 to 440 nm and an incident angle of 0 degrees is defined as UV50. (0deg) The wavelength UV at which the transmittance is 50% in the spectral transmittance curve at a wavelength of 400 to 440 nm and an incident angle of 30 degrees is defined as UV50. (30deg) When The wavelength UV50 (0deg) and the wavelength UV50 (30deg) The absolute difference is 5 nm or less

[0047] The dye (U) is a UV dye described below, and by containing an ultraviolet absorbing dye in the substrate, the degradation of the spectral characteristics of the dielectric multilayer film at high angles of incidence, such as the occurrence of light leakage and noise in the ultraviolet range, can be suppressed by the absorption characteristics of the substrate.

[0048] By satisfying the spectral characteristic (i-24), it is meant that there is little shift even at high incident angles and color reproducibility is excellent in the ultraviolet light absorption onset band of wavelengths from 400 to 440 nm. The spectral characteristic (i-24) is preferably 3 nm or less, and more preferably 2 nm or less.

[0049] <Dielectric multilayer film> In this filter, the dielectric multilayer film is laminated as the outermost layer on at least one of the main surfaces of the substrate.

[0050] In the present filter, it is preferable that the dielectric multilayer film satisfies all of the following spectral characteristics (iv-1) to (iv-12). Spectral characteristics (iv-1)~(iv-6) of the spectral transmittance curve at an incident angle of 0 degrees: (iv-1) Average transmittance T at wavelengths of 440 to 490 nm 440-490(0deg)AVE Over 90% (iv-2) Average transmittance T at wavelengths of 490 to 560 nm 490-560(0deg)AVE Over 90% (iv-3) Average transmittance T at wavelengths of 560 to 590 nm560-590(0deg)AVE Over 90% (iv-4) IR50, the shortest wavelength at which the transmittance is 50% after 600 nm (0deg) is in the range of 630 to 730 nm (iv-5) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(0deg)MAX More than 25% (iv-6) Maximum transmittance T at wavelengths of 760 to 900 nm 760-900(0deg)MAX is less than 2%

[0051] Spectral characteristics (iv-7)~(iv-12) of the spectral transmittance curve at an incident angle of 30 degrees: (iv-7) Average transmittance T at wavelengths of 440 to 490 nm 440-490(30deg)AVE Over 90% (iv-8) Average transmittance T at wavelengths of 490 to 560 nm 490-560(30deg)AVE Over 90% (iv-9) Average transmittance T at wavelengths of 560 to 590 nm 560-590(30deg)AVE Over 90% (iv-10) IR50, the shortest wavelength at which the transmittance is 50% after 600 nm (30deg) is in the range of 630 to 730 nm (iv-11) Maximum transmittance T at wavelengths of 700 to 760 nm 700-760(30deg)MAX More than 25% (iv-12) Maximum transmittance T at wavelengths of 760 to 900 nm 760-900(30deg)MAX is less than 2%

[0052] Satisfying the spectral characteristics (iv-1) to (iv-3) means that the transmittance in the visible light range is excellent. T 440-490(0deg)AVE is preferably 92% or more, more preferably 93% or more. T 490-560(0deg)AVE is preferably 91% or more, more preferably 92% or more. T 560-590(0deg)AVE is preferably 92% or more, more preferably 93% or more.

[0053] By satisfying the spectral characteristics (iv-4), it is possible to block infrared light and efficiently capture visible light. (0deg) is preferably in the range of 640 to 720 nm, More preferably, it is in the range of 650 to 710 nm.

[0054] Satisfying the spectral characteristic (iv-5) means that light leakage (ripple) from the dielectric multilayer film may occur at wavelengths of 700 to 760 nm. T 700-760(0deg)MAX is preferably 30% or more, more preferably 50% or more.

[0055] By satisfying the spectral characteristic (iv-6), it means that the film has excellent light-blocking properties in the wavelength range of 760 to 900 nm. 760-900(0deg)MAX is preferably 1.8% or less, more preferably 1.5% or less.

[0056] Satisfying the spectral characteristics (iv-7) to (iv-9) means that the transmittance in the visible light range is excellent even at a high angle of incidence. T 440-490(30deg)AVE is preferably 92% or more, more preferably 93% or more. T 490-560(30deg)AVE is preferably 92% or more, more preferably 93% or more. T 560-590(30deg)AVE is preferably 92% or more, more preferably 93% or more.

[0057] By satisfying the spectral characteristics (iv-10), it means that a large amount of visible light can be captured even at high angles of incidence. (30deg) is preferably in the range of 640 to 720 nm, more preferably in the range of 650 to 710 nm.

[0058] By satisfying the spectral characteristic (iv-11), it means that light leakage (ripple) from the dielectric multilayer film may occur at wavelengths of 700 to 760 nm even at high incident angles. T 700-760(30deg)MAX is preferably 30% or more, more preferably 50% or more.

[0059] By satisfying the spectral characteristics (iv-12), it means that the film has excellent light-blocking properties in the wavelength range of 760 to 900 nm even at high incident angles. 760-900(30deg)MAX is preferably 1.8% or less, more preferably 1.5% or less.

[0060] As shown in the above spectral characteristic (iv-5), the dielectric multilayer film of the present invention may exhibit light leakage (ripple) in the wavelength range of 700 to 760 nm at an incident angle of 0 degrees. This wavelength range is absorbed by the NIR dye in the resin film, which will be described later, so even if light leakage occurs, the optical filter as a whole will block light. Furthermore, in a multilayer film designed to exhibit light leakage in the wavelength range of 700 to 760 nm, light leakage is unlikely to occur in the wavelength range of 800 to 900 nm even at high incident angles. On the other hand, in a multilayer film that has no light leakage at an incident angle of 0 degrees, light leakage occurs around 800 nm at a very high incident angle of around 70 degrees. To cover this with the absorption ability of the NIR dye, it is necessary to use a dye that has a maximum absorption wavelength after 800 nm. However, dyes that have absorption ability after 800 nm have the tendency to also absorb light in the visible light region, which reduces the visible light transmittance of the entire optical filter. The optical filter of the present invention is an optical filter that combines such a dielectric multilayer film with a resin film described later, thereby achieving high visible light transmittance as shown in the spectral characteristics (i-1) to (i-3) and suppressing oblique incidence shift as shown in the spectral characteristics (i-20) to (i-23).

[0061] In this filter, at least one of the dielectric multilayer films is preferably designed as a near-infrared reflective layer (hereinafter also referred to as an NIR reflective layer), and the other of the dielectric multilayer films is preferably designed as an NIR reflective layer, a reflective layer having a reflection range other than the near-infrared range, or an anti-reflection layer.

[0062] The NIR reflective layer is a dielectric multilayer film designed to block light in the near-infrared region. The NIR reflective layer has wavelength selectivity that transmits visible light and mainly reflects light in the near-infrared region other than the light-shielding region of the resin film that is the absorption layer. The reflective region of the NIR reflective layer may include the light-shielding region of the resin film in the near-infrared region. The NIR reflective layer is not limited to NIR reflection characteristics, and may be appropriately designed to further block light in wavelength regions other than the near-infrared region, for example, the near-ultraviolet region.

[0063] The NIR reflective layer is composed of, for example, a dielectric multilayer film in which dielectric films with low refractive index (low refractive index film) and dielectric films with high refractive index (high refractive index film) are alternately laminated. The high refractive index film preferably has a refractive index of 1.6 or more, more preferably 2.2 to 2.5. Examples of materials for the high refractive index film include Ta2O5, TiO2, and Nb2O5. Of these, TiO2 is preferred in terms of film formability, reproducibility in refractive index, etc., and stability.

[0064] On the other hand, the low refractive index film preferably has a refractive index of less than 1.6, more preferably 1.45 or more and less than 1.55. Examples of materials for the low refractive index film include SiO2, SiO x N y In terms of reproducibility, stability, economy, etc. in film formation, SiO2 is preferred.

[0065] To create a multilayer film that allows light leakage (ripple) in the wavelength range of 700 to 760 nm at an incident angle of 0 degrees, it is possible to combine several types of dielectric multilayer films with different spectral characteristics to transmit and select the desired wavelength band. Specifically, the reflected light can be biased by adjusting the balance of silica and titania to adjust the desired light blocking band.

[0066] The total number of laminated layers of the dielectric multilayer film constituting the NIR reflective layer is preferably 20 or more, more preferably 30 or more, and even more preferably 35 or more. However, since a large total number of laminated layers can cause warping or an increase in film thickness, the total number of laminated layers is preferably 100 or less, more preferably 75 or less, and even more preferably 60 or less. The overall thickness of the reflective layer is preferably 2 to 10 μm.

[0067] If the total number of layers and thickness of the dielectric multilayer film are within the above ranges, the NIR reflective layer satisfies the requirement for miniaturization, and the incidence angle dependency can be suppressed while maintaining high productivity.

[0068] The dielectric multilayer film can be formed by vacuum film-forming processes such as CVD, sputtering, and vacuum deposition, or wet film-forming processes such as spraying and dipping.

[0069] The NIR reflective layer may be a single layer (a group of dielectric multilayer films) that provides predetermined optical characteristics, or two layers that provide predetermined optical characteristics. When there are two or more layers, the reflective layers may have the same or different configurations. When there are two or more reflective layers, they are usually composed of multiple reflective layers with different reflection bands. When two reflective layers are provided, one may be a near-infrared reflective layer that blocks light in the short wavelength band of the near-infrared region, and the other may be a near-infrared / near-ultraviolet reflective layer that blocks light in both the long wavelength band of the near-infrared region and the near-ultraviolet region.

[0070] Examples of antireflection layers include dielectric multilayer films, intermediate refractive index media, and moth-eye structures in which the refractive index changes gradually. Among these, dielectric multilayer films are preferred from the viewpoints of optical efficiency and productivity. Antireflection layers are obtained by alternately laminating dielectric multilayer films, similar to reflective layers.

[0071] <Base material> In the optical filter of the present invention, the substrate has a resin film containing an NIR dye (IR) and a resin, which will be described later.

[0072] <Spectral characteristics of resin film> The resin film preferably satisfies all of the following spectral properties (ii-1) to (ii-4). (ii-1) Average internal transmittance T in the spectral transmittance curve at wavelengths of 440 to 490 nm 440-490AVE Over 84% (ii-2) Average internal transmittance T in the spectral transmittance curve at wavelengths of 490 to 560 nm490-560AVE is 94% or more (ii-3) The average internal transmittance T in the spectral transmittance curve at wavelengths of 560 to 590 nm 560-590AVE is 80% or more (ii-4) The maximum internal transmittance T in the spectral transmittance curve at wavelengths of 700 to 760 nm 700-760MAX is 5% or less

[0073] Satisfying the spectral characteristics (ii-1) to (ii-3) means that the resin film has high transmittance in the visible light region. T 440-490AVE is preferably 85% or more, more preferably 86% or more. T 490-560AVE is preferably 95% or more, more preferably 96% or more. T 560-590AVE is preferably 84% or more, more preferably 86% or more.

[0074] Satisfying the spectral characteristic (ii-4) means that the resin film can widely absorb light in the wavelength range of 700 to 760 nm. T 700-760MAX is preferably 1% or less, more preferably 0.5% or less.

[0075] The resin film preferably further satisfies the following spectral characteristic (ii-5). (ii-5) The maximum internal transmittance T in the spectral transmittance curve at wavelengths of 760 to 800 nm 760-800MAX is 15% or less T 760-800MAX is preferably 1% or less, more preferably 0.5% or less.

[0076] <NIR Dye> The NIR dye (IR) is a NIR dye having a maximum absorption wavelength at 680 to 800 nm in the resin. By containing such a dye, near-infrared light can be effectively cut. Also, the resin is the resin constituting the resin film.

[0077] The dye (IR) preferably satisfies all of the following spectral characteristics (iii-1) to (iii-3) in the spectral transmittance curve of a coating film obtained by dissolving the dye (IR) in a resin and coating the resin on an alkali glass plate so that the transmittance at the maximum absorption wavelength is 10%. (iii-1) Average internal transmittance T in the spectral transmittance curve at wavelengths of 440 to 490 nm 440-490AVE Over 94% (iii-2) Average internal transmittance T in the spectral transmittance curve at wavelengths of 490 to 560 nm 490-560AVE Over 94% (iii-3) Average internal transmittance T in the spectral transmittance curve at wavelengths of 560 to 590 nm 560-590AVE Over 94%

[0078] Satisfying the spectral characteristics (iii-1) to (iii-3) means that the transmittance in the visible light region is high. T 440-490AVE is preferably 95% or more, more preferably 96% or more. T 490-560AVE is preferably 96% or more, more preferably 98% or more. T 560-590AVE is preferably 95% or more, more preferably 96% or more.

[0079] The NIR dye (IR) may consist of one type of compound, or may contain two or more types of compounds. From the viewpoint of easily satisfying the above-mentioned spectral characteristic (ii-4) of the resin film, that is, absorbing light over a wide wavelength range of 700 to 760 nm, it is preferable that the NIR dye (IR) contains three or more types of compounds having a maximum absorption wavelength in the range of 680 to 800 nm in the resin, and it is particularly preferable that the NIR dye (IR) contains one or more types of compounds selected from each of the compounds (A) to (C) having the following characteristics: Compound (A): A compound having a maximum absorption wavelength in a resin at a wavelength of 680 nm or more and less than 720 nm Compound (B): A compound having a maximum absorption wavelength in a resin at a wavelength of 720 nm or more and less than 740 nm Compound (C): A compound having a maximum absorption wavelength in a resin of 740 nm or more and 780 nm or less.

[0080] The NIR dye (IR) is preferably selected from squarylium dyes or cyanine dyes from the viewpoints of transparency in the visible light range, solubility in resins, and durability.

[0081] <Squarylium dyes> The squarylium dye is preferably a compound represented by the following formula (I) or (II). When two or more identical symbols are present in a squarylium dye compound, the symbols may be the same or different. The same applies to cyanine dyes.

[0082] <Squarylium Compounds (I)>

[0083] [ka]

[0084] However, the symbols in the above formula are as follows: R 24 and R 26 are each independently a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group or an alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, an araryl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms, -NR 27 R 28 (R 27 and R 28 are each independently a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or -C(=O)-R 29 (R 29 represents a hydrogen atom, a halogen atom, a hydroxyl group, a hydrocarbon group having 1 to 25 carbon atoms which may have a substituent and which may contain an unsaturated bond between carbon atoms, an oxygen atom, or a saturated or unsaturated ring structure), -NHR 30 , or -SO2-R 30 (R 30represents a hydrocarbon group having 1 to 25 carbon atoms, each of which may have one or more hydrogen atoms substituted with a halogen atom, a hydroxyl group, a carboxyl group, a sulfo group, or a cyano group, and which may contain an unsaturated bond, an oxygen atom, or a saturated or unsaturated ring structure between carbon atoms), or a group represented by the following formula (S): 41 , R 42 are independently a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 10 carbon atoms. k is 2 or 3.

[0085] [ka]

[0086] R 21 and R 22 , R 22 and R 25 , and R 21 and R 23 may be linked to each other to form, together with the nitrogen atom, 5- or 6-membered heterocycles A, B, and C, respectively. R when heterocycle A is formed 21 and R 22 represents a divalent group -Q- to which they are bonded, which is an alkylene group or alkyleneoxy group in which a hydrogen atom may be substituted with an alkyl group having 1 to 6 carbon atoms, an aryl group having 6 to 10 carbon atoms, or an acyloxy group having 1 to 10 carbon atoms which may have a substituent. R when heterocycle B is formed 22 and R 25 and R when heterocycle C is formed. 21 and R 23 are the divalent groups -X 1 -Y 1 - and -X 2 -Y 2 - (The side that is bonded to nitrogen is X 1 and X 2 ) as X 1 and X 2 are groups represented by the following formula (1x) or (2x), and Y 1 and Y2 are each a group selected from the following formulas (1y) to (5y): 1 and X 2 are groups represented by the following formula (2x), Y 1 and Y 2 may each be a single bond, in which case there may be an oxygen atom between the carbon atoms.

[0087] [ka]

[0088] In formula (1x), four Z's each independently represent a hydrogen atom, a hydroxyl group, an alkyl group or an alkoxy group having 1 to 6 carbon atoms, or -NR 38 R 39 (R 38 and R 39 R each independently represents a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. 31 ~R 36 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms, R 37 represents an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. R 27 , R 28 , R 29 , R 31 ~R 37 , R when not forming a heterocycle 21 ~R 23 , and R 25 may be bonded to any other of these to form a 5- or 6-membered ring. 31 and R 36 , R 31 and R 37 may be directly bonded. When a heterocyclic ring is not formed, R 21 , R 22 , R 23 and R 25each independently represents a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl group or alkoxy group having 1 to 20 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, an aryl group having 6 to 11 carbon atoms, or an araryl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms.

[0089] Examples of compound (I) include compounds represented by any of formulas (I-1) to (I-3). From the viewpoints of solubility in resin, heat resistance and light resistance in resin, and visible light transmittance of a resin layer containing the compound, the compound represented by formula (I-1) is particularly preferred.

[0090] [ka]

[0091] The symbols in formulae (I-1) to (I-3) have the same definitions as those of the same symbols in formula (I), and the preferred embodiments are also the same.

[0092] In compound (I-1), X 1 As the group (2x), the group (2x) is preferred. 1 is preferably a single bond or a group (1y). 31 ~R 36 is preferably a hydrogen atom or an alkyl group having 1 to 3 carbon atoms, more preferably a hydrogen atom or a methyl group. 1 -X 1 Specific examples of - include divalent organic groups represented by formulas (11-1) to (12-3).

[0093] -C(CH3)2-CH(CH3)- …(11-1) -C(CH3)2-CH2- …(11-2) -C(CH3)2-CH(C2H5)- …(11-3) -C(CH3)2-C(CH3)(nC3H7)- …(11-4) -C(CH3)2-CH2-CH2- …(12-1) -C(CH3)2-CH2-CH(CH3)- …(12-2) -C(CH3)2-CH(CH3)-CH2- …(12-3)

[0094] In addition, in compound (I-1), R 21 are more preferably independently a group represented by formula (4-1) or (4-2) from the viewpoints of solubility, heat resistance, and the steepness of the change in the spectral transmittance curve near the boundary between the visible region and the near-infrared region.

[0095] [ka]

[0096] In formula (4-1) and formula (4-2), R 71 ~R 75 are independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.

[0097] In compound (I-1), R 24 Ha-NR 27 R 28 -NR is preferred. 27 R 28 From the viewpoint of solubility in resins and coating solvents, -NH-C(=O)-R 29 or -NH-SO2-R 30 is preferred.

[0098] In compound (I-1), R 24 -NH-C(=O)-R 29 The compound is shown in formula (I-11).

[0099] [ka]

[0100] R 23 and R 26 are each independently preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms, and more preferably a hydrogen atom.

[0101] R 29 The substituent is preferably an alkyl group having 1 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 10 carbon atoms which may have a substituent, or an araryl group having 7 to 18 carbon atoms which may have a substituent and which may have an oxygen atom between the carbon atoms. Examples of the substituent include a hydroxyl group, a carboxy group, a sulfo group, a cyano group, an alkyl group having 1 to 6 carbon atoms, a fluoroalkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, and an acyloxy group having 1 to 6 carbon atoms.

[0102] R 29 is preferably a group selected from a linear, branched, or cyclic alkyl group having 1 to 17 carbon atoms, a phenyl group which may be substituted with an alkoxy group having 1 to 6 carbon atoms, and an araryl group having 7 to 18 carbon atoms which may have an oxygen atom between the carbon atoms.

[0103] R 29 As the alkyl group, a hydrocarbon group having 5 to 25 carbon atoms and at least one branch, in which one or more hydrogen atoms may be independently substituted with a hydroxyl group, a carboxyl group, a sulfo group, or a cyano group, and which may contain an unsaturated bond, an oxygen atom, or a saturated or unsaturated ring structure between carbon atoms, can also be preferably used.

[0104] More specifically, compound (I-11) includes the compounds shown in the following table: In the compounds shown in the following table, the symbols on the left and right of the squarylium skeleton have the same meaning.

[0105] [Table 1]

[0106] Of these, compounds (I-11-1) to (I-11-12) are preferred as compound (I-11) from the viewpoints of visible light transmittance, solubility in resin, and durability, and compounds (I-11-1) to (I-11-4) are even more preferred from the viewpoints of solubility in resin and durability.

[0107] In compound (I-1), R 24 -NH-SO2-R 30 The compound is shown in formula (I-12).

[0108] [ka]

[0109] R 23 and R 26 are each preferably a hydrogen atom, a halogen atom, or an alkyl or alkoxy group having 1 to 6 carbon atoms, and more preferably a hydrogen atom.

[0110] R 30 From the viewpoint of light resistance, R is preferably an alkyl group or alkoxy group having 1 to 12 carbon atoms, which may be branched, or a hydrocarbon group having 6 to 16 carbon atoms and an unsaturated ring structure. Examples of the unsaturated ring structure include benzene, toluene, xylene, furan, and benzofuran. 30 are more preferably independently an alkyl group or alkoxy group having 1 to 12 carbon atoms, which may have a branch. 30 In each group represented by the formula (I), some or all of the hydrogen atoms may be substituted with halogen atoms, particularly fluorine atoms.

[0111] More specifically, compound (I-12) includes the compounds shown in the following table: In the compounds shown in the following table, the symbols on the left and right of the squarylium skeleton have the same meaning.

[0112] [Table 2]

[0113] Of these, compounds (I-12-1) to (I-12-8) and (I-12-13) to (I-12-20) are preferred as compound (I-12) from the viewpoints of visible light transmittance, solubility in resin, and durability. Of these, compounds (I-12-1) to (I-12-5) are even more preferred from the viewpoints of solubility in resin and durability.

[0114] <Squarylium Compounds (II)>

[0115] [ka]

[0116] However, the symbols in the above formula are as follows: Each ring Z is independently a 5- or 6-membered ring having 0 to 3 heteroatoms in the ring, and the hydrogen atoms in ring Z may be substituted. R 1 and R 2 , R 2 and R 3 , and R 1 The carbon atoms or heteroatoms constituting ring Z may be bonded to each other to form heterocycles A1, B1, and C1 together with the nitrogen atom, respectively, and in this case, the hydrogen atoms of heterocycles A1, B1, and C1 may be substituted. 1 and R 2 R each independently represents a hydrogen atom, a halogen atom, or a hydrocarbon group which may contain an unsaturated bond between carbon atoms, a heteroatom, or a saturated or unsaturated ring structure and which may have a substituent. 4 and R when no heterocycle is formed. 3 each independently represents a hydrogen atom, a halogen atom, or an alkyl or alkoxy group which may contain a heteroatom between carbon atoms and which may have a substituent.

[0117] Examples of compound (II) include compounds represented by any of formulas (II-1) to (II-3). From the viewpoints of solubility in resins and visible light transmittance in resins, the compound represented by formula (II-3) is particularly preferred.

[0118] [ka]

[0119] In formula (II-1) and formula (II-2), R 1 and R 2 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms which may have a substituent, and R 3 ~R 6 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 10 carbon atoms which may have a substituent.

[0120] In formula (II-3), R 1 , R 4 , and R 9 ~R 12 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms which may have a substituent, and R 7 and R 8 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may have a substituent.

[0121] R in Compound (II-1) and Compound (II-2) 1 and R 2 are each independently preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 7 to 15 carbon atoms, from the viewpoints of solubility in resin, visible light transmittance, etc., and R 1 and R 2 More preferably, at least one of R is a branched alkyl group having 7 to 15 carbon atoms, 1 and R 2 It is particularly preferable that both of the groups are alkyl groups having a branched chain and having 8 to 15 carbon atoms.

[0122] R in compound (II-3)1 From the viewpoints of solubility in a transparent resin, visible light transmittance, etc., each of the groups is preferably an alkyl group having 1 to 15 carbon atoms, more preferably an alkyl group having 1 to 10 carbon atoms, and particularly preferably an ethyl group or an isopropyl group.

[0123] R 4 From the viewpoints of visible light transmittance and ease of synthesis, is preferably a hydrogen atom or a halogen atom, and particularly preferably a hydrogen atom. R 7 and R 8 are each preferably a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom, and more preferably a hydrogen atom, a halogen atom, or a methyl group.

[0124] R 9 ~R 12 are preferably independently a hydrogen atom, a halogen atom, or an alkyl group having 1 to 5 carbon atoms which may be substituted with a halogen atom. -CR 9 R 10 -CR 11 R 12 Examples of - include divalent organic groups represented by the following groups (13-1) to (13-5). -CH(CH3)-C(CH3)2- …(13-1) -C(CH3)2-CH(CH3)- …(13-2) -C(CH3)2-CH2- …(13-3) -C(CH3)2-CH(C2H5)- …(13-4) -CH(CH3)-C(CH3)(CH2-CH(CH3)2)-…(13-5)

[0125] More specifically, examples of compound (II-3) include the compounds shown in the following table: In the compounds shown in the following table, the symbols on the left and right of the squarylium skeleton have the same meaning.

[0126] [Table 3]

[0127] Of these, compounds (II-3-1) to (II-3-4) are preferred as compound (II-3) from the viewpoints of visible light transmittance, solubility in resin, and durability, and compound (II-3-2) is particularly preferred from the viewpoint of solubility in resin.

[0128] Compounds (I) and (II) can be produced by known methods. Compound (I) can be produced by the methods described in U.S. Pat. No. 5,543,086, U.S. Patent Application Publication No. 2014 / 0061505, and WO 2014 / 088063. Compound (II) can be produced by the method described in WO 2017 / 135359.

[0129] <Cyanine dye> The cyanine dye is preferably a compound represented by the following formula (III).

[0130] <Cyanine Compound (III)>

[0131] [ka]

[0132] However, the symbols in the above formula are as follows: R 101 ~R 109 R each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 15 carbon atoms which may have a substituent, or an aryl group having 5 to 20 carbon atoms. 110 ~R 114 each independently represents a hydrogen atom, a halogen atom, or an alkyl group having 1 to 15 carbon atoms. X - indicates a monovalent anion. n1 is 0 or 1. -(CH2) n1 A hydrogen atom bonded to a carbocyclic ring containing - may be substituted with a halogen atom, an alkyl group having 1 to 15 carbon atoms which may have a substituent, or an aryl group having 5 to 20 carbon atoms.

[0133] In the above, the alkyl group (including the alkyl group of an alkoxy group) may be linear or may have a branched structure or a saturated ring structure. The aryl group refers to a group that bonds via a carbon atom constituting an aromatic ring of an aromatic compound, such as a benzene ring, naphthalene ring, biphenyl, furan ring, thiophene ring, or pyrrole ring. Examples of the substituent in the alkyl group or alkoxy group having 1 to 15 carbon atoms or the aryl group having 5 to 20 carbon atoms that may have a substituent include a halogen atom and an alkoxy group having 1 to 10 carbon atoms.

[0134] In formula (III), R 101 is preferably an alkyl group having 1 to 15 carbon atoms or an aryl group having 5 to 20 carbon atoms, and more preferably a branched alkyl group having 1 to 15 carbon atoms from the viewpoint of maintaining high visible light transmittance in the resin.

[0135] In formula (III), R 102 ~R 105 , R 108 , R 109 are each independently preferably a hydrogen atom, an alkyl or alkoxy group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms, and more preferably a hydrogen atom from the viewpoint of obtaining a high visible light transmittance.

[0136] In formula (III), R 110 ~R 114 are each independently preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms, and more preferably a hydrogen atom from the viewpoint of obtaining a high visible light transmittance.

[0137] R 106 , R 107 are each independently preferably a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms (which may include a linear, cyclic, or branched alkyl group), more preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms. 106 and R 107 are preferably the same group.

[0138] X- As for I - , BF4 - , PF6 - , ClO4 - , anions represented by formula (X1) and (X2), etc., and preferably BF4 - , or PF6 - is.

[0139] [ka]

[0140] In the following description, R 101 ~R 114 The part excluding is also called skeleton (III).

[0141] In formula (III), a compound in which n1 is 1 is shown in formula (III-1) below, and a compound in which n1 is 0 is shown in formula (III-2) below.

[0142] [ka]

[0143] In formula (III-1) and formula (III-2), R 101 ~R 114 and X - is the same as in formula (III). 115 ~R 120 R each independently represents a hydrogen atom, a halogen atom, an alkyl group or alkoxy group having 1 to 15 carbon atoms which may have a substituent, or an aryl group having 5 to 20 carbon atoms. 115 ~R 120 are each independently preferably a hydrogen atom, an alkyl group having 1 to 15 carbon atoms, or an aryl group having 5 to 20 carbon atoms (which may include a linear, cyclic, or branched alkyl group), more preferably a hydrogen atom or an alkyl group having 1 to 15 carbon atoms. 115 ~R 120 are preferably the same group.

[0144] As the compound represented by formula (III), the compound represented by formula (III-1) is particularly preferred. More specifically, the compounds represented by formula (III-1) include compounds in which the atoms or groups bonded to each skeleton are the atoms or groups shown in the table below. In all of the compounds shown in the table below, R 101 ~R 109 are all identical on both sides of the equation.

[0145] R in the table below 110 -R 114 indicates the atom or group bonded to the central benzene ring of each formula, and when all five are hydrogen atoms, it is written as "H". 110 -R 114 If one of the groups is a substituent and the other is a hydrogen atom, only the combination of the symbol and the substituent is described. For example, "R 112 -C(CH3)3" is R 112 is -C(CH3)3, and the rest are hydrogen atoms.

[0146] R in Table 4 115 -R 120 represents an atom or group bonded to the central cyclohexane ring in formula (III-1), and when all six are hydrogen atoms, it is written as "H". 115 -R 120 When one of the groups is a substituent and the other is a hydrogen atom, only the combination of the symbol of the substituent and the substituent is shown.

[0147] [Table 4]

[0148] Among these, compounds (III-1-1) to (III-1-12) are preferred as compound (III-1) from the viewpoints of visible light transmittance, solubility in resins, and durability. Among these, compounds (III-1-2), (III-1-6), and (III-1-9) are more preferred from the viewpoints of visible light transmittance and durability.

[0149] The pigment (III) can be produced by, for example, the methods described in Dyes and pigments 73(2007) 344-352 and J.Heterocyclic chem,42,959(2005).

[0150] The content of the NIR pigment (IR) in the resin film is preferably 0.1 to 25 parts by mass, more preferably 0.3 to 15 parts by mass, based on 100 parts by mass of the resin. When combining two or more compounds, the above content is the sum of each compound. When the NIR pigment (IR) contains the compounds (A) to (C), the content of the compound (A) is preferably 0.5 to 5 parts by mass, the content of the compound (B) is preferably 0.5 to 5 parts by mass, and the content of the compound (C) is preferably 0.5 to 5 parts by mass, based on 100 parts by mass of the resin.

[0151] <UV pigment> The pigment (U) is a UV pigment having a maximum absorption wavelength in the resin at 370 to 430 nm. By containing such a pigment, ultraviolet light can be effectively cut off.

[0152] Examples of the pigment (U) include oxazole pigments, merocyanine pigments, cyanine pigments, naphthalimide pigments, oxadiazole pigments, oxazine pigments, oxazolidine pigments, naphthalic acid pigments, styryl pigments, anthracene pigments, cyclic carbonyl pigments, triazole pigments, etc. Among these, merocyanine pigments are particularly preferred. Also, one kind may be used alone, or two or more kinds may be used in combination.

[0153] As the pigment (U), particularly, a merocyanine pigment represented by the following formula (M) is preferred.

[0154]

Chemical formula

[0155] The symbols in the formula (M) are as follows.

[0156] R1 represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent. The substituent is preferably an alkoxy group, an acyl group, an acyloxy group, a cyano group, a dialkylamino group, or a chlorine atom. The alkoxy group, acyl group, acyloxy group, and dialkylamino group preferably have 1 to 6 carbon atoms.

[0157] Unsubstituted R 1 Specifically, preferred are alkyl groups having 1 to 12 carbon atoms in which some of the hydrogen atoms may be substituted with an aliphatic ring, an aromatic ring, or an alkenyl group; cycloalkyl groups having 3 to 8 carbon atoms in which some of the hydrogen atoms may be substituted with an aromatic ring, an alkyl group, or an alkenyl group; and aryl groups having 6 to 12 carbon atoms in which some of the hydrogen atoms may be substituted with an aliphatic ring, an alkyl group, or an alkenyl group.

[0158] R 1 When is an unsubstituted alkyl group, the alkyl group may be linear or branched, and more preferably has 1 to 6 carbon atoms.

[0159] R 1 is an alkyl group having 1 to 12 carbon atoms in which some of the hydrogen atoms are substituted with an aliphatic ring, an aromatic ring, or an alkenyl group, an alkyl group having 1 to 4 carbon atoms having a cycloalkyl group having 3 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms substituted with a phenyl group is more preferred, and an alkyl group having 1 or 2 carbon atoms substituted with a phenyl group is particularly preferred. Note that an alkyl group substituted with an alkenyl group means an alkenyl group as a whole that does not have an unsaturated bond between the 1- and 2-positions, such as an allyl group or a 3-butenyl group.

[0160] Preferred R 1 is an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms may be substituted with a cycloalkyl group or a phenyl group. 1 is an alkyl group having 1 to 6 carbon atoms, and specific examples thereof include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group.

[0161] R 2 ~R 5 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms. The alkyl group and alkoxy group preferably have 1 to 6 carbon atoms, and more preferably 1 to 4 carbon atoms.

[0162] R 2 and R 3 At least one of R is preferably an alkyl group, and more preferably both are alkyl groups. 2 and R 3 When R is not an alkyl group, a hydrogen atom is more preferred. 2 and R 3 In any case, an alkyl group having 1 to 6 carbon atoms is particularly preferred.

[0163] R 4 and R 5 At least one of R is preferably a hydrogen atom, and more preferably both are hydrogen atoms. 4 or R 5 When is not a hydrogen atom, it is preferably an alkyl group having 1 to 6 carbon atoms.

[0164] Y is R 6 and R 7 represents a methylene group or an oxygen atom substituted with R 6 and R 7 each independently represents a hydrogen atom, a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an alkoxy group having 1 to 10 carbon atoms.

[0165] X represents any one of the divalent groups represented by the following formulas (X1) to (X5).

[0166] [ka]

[0167] R 8 and R 9each independently represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, and R 10 ~R 19 each independently represents a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent. R 8 ~R 19 The substituents of R 1 The same substituents as those in R are mentioned, and the preferred embodiments are also the same. 8 ~R 19 is a hydrocarbon group having no substituents, R 1 The same aspects as above can be mentioned.

[0168] In formula (X1), R 8 and R 9 may be different groups, but are preferably the same group. 8 and R 9 When is an unsubstituted alkyl group, it may be linear or branched, and more preferably has 1 to 6 carbon atoms.

[0169] Preferred R 8 and R 9 Each of R is an alkyl group having 1 to 6 carbon atoms in which some of the hydrogen atoms may be substituted with a cycloalkyl group or a phenyl group. 8 and R 9 are all alkyl groups having 1 to 6 carbon atoms, and specific examples include a methyl group, an ethyl group, an n-propyl group, an isopropyl group, an n-butyl group, an isobutyl group, and a t-butyl group.

[0170] In formula (X2), R 10 and R 11 are more preferably alkyl groups having 1 to 6 carbon atoms, and it is particularly preferred that they are the same alkyl groups.

[0171] In formula (X3), R 12 and R 15are preferably both hydrogen atoms or unsubstituted alkyl groups having 1 to 6 carbon atoms. 13 and R 14 are preferably all hydrogen atoms or all alkyl groups having 1 to 6 carbon atoms.

[0172] In formula (X4), two groups R bonded to the same carbon atom 16 and R 17 and R 18 and R 19 are preferably all hydrogen atoms or all alkyl groups having 1 to 6 carbon atoms.

[0173] The compound (M) can be produced by a known method.

[0174] The content of the UV dye (U) in the resin film is preferably 0.1 to 15 parts by mass, more preferably 1 to 10 parts by mass, per 100 parts by mass of the resin. Within this range, the resin properties are unlikely to deteriorate.

[0175] <Base material composition> The substrate in the present filter may have a single-layer structure or a multi-layer structure, and the material of the substrate is not particularly limited, and may be an organic or inorganic material as long as it is a transparent material that transmits visible light of 400 to 700 nm. When the substrate has a single layer structure, it is preferable that the substrate is a resin substrate made of a resin film containing a resin and an NIR dye (IR). When the substrate has a multi-layer structure, a composite substrate is preferred in which a resin film containing an NIR dye (IR) is laminated on at least one main surface of the support, and the support is preferably made of a transparent resin or a transparent inorganic material.

[0176] The resin is not limited as long as it is a transparent resin, and one or more transparent resins selected from polyester resin, acrylic resin, epoxy resin, enethiol resin, polycarbonate resin, polyether resin, polyarylate resin, polysulfone resin, polyethersulfone resin, polyparaphenylene resin, polyarylene ether phosphine oxide resin, polyamide resin, polyimide resin, polyamideimide resin, polyolefin resin, cyclic olefin resin, polyurethane resin, polystyrene resin, etc. These resins may be used alone or in combination of two or more. From the viewpoint of the spectral characteristics, glass transition temperature (Tg) and adhesiveness of the resin film, one or more resins selected from polyimide resin, polycarbonate resin, polyester resin and acrylic resin are preferred.

[0177] When a plurality of compounds are used as the NIR dye (IR) or other dyes, they may be contained in the same resin film, or may be contained in separate resin films.

[0178] As the transparent inorganic material, glass or crystalline material is preferred. Examples of glass that can be used for the support include absorption-type glass (near-infrared absorbing glass) containing copper ions in fluorophosphate glass or phosphate glass, soda-lime glass, borosilicate glass, alkali-free glass, and quartz glass. As the glass, phosphate glass and fluorophosphate glass are preferred from the viewpoint of absorbing infrared light (especially 900 to 1200 nm). Note that "phosphate glass" also includes silicophosphate glass, in which part of the glass skeleton is composed of SiO2.

[0179] The glass may be chemically strengthened glass obtained by ion exchange at a temperature equal to or lower than the glass transition point to exchange alkali metal ions (e.g., Li ions, Na ions) having a small ionic radius present on the main surface of the glass plate with alkali ions having a larger ionic radius (e.g., Na ions or K ions for Li ions, and K ions for Na ions).

[0180] Examples of crystalline materials that can be used for the support include birefringent crystals such as quartz, lithium niobate, and sapphire.

[0181] As the support, inorganic materials are preferred, and glass and sapphire are particularly preferred, from the viewpoint of shape stability related to long-term reliability of optical properties, mechanical properties, etc., and ease of handling during filter production.

[0182] The resin film can be formed by dissolving or dispersing the dye (IR), resin or resin raw material components, and other components blended as needed in a solvent to prepare a coating solution, applying the coating solution to a support, drying, and optionally curing. The support may be the support included in the filter, or a peelable support used only when forming the resin film. The solvent may be a dispersion medium or a solvent capable of stably dispersing the dye (IR).

[0183] The coating liquid may also contain a surfactant to prevent voids caused by microbubbles, depressions caused by the adhesion of foreign matter, and repellency during the drying process. For example, the coating liquid can be applied by dip coating, cast coating, or spin coating. After the coating liquid is applied to a support, a resin film is formed by drying. When the coating liquid contains raw materials for a transparent resin, it is further subjected to a curing treatment such as thermal curing or photocuring.

[0184] The resin film can also be produced in a film form by extrusion molding. When the substrate has a single-layer structure (resin substrate) consisting of a resin film containing the dye (I), the resin film can be used as is as the substrate. When the substrate has a multi-layer structure (composite substrate) having a support and a resin film containing the dye (I) laminated on at least one main surface of the support, the substrate can be produced by laminating this film on the support and integrating them by thermocompression bonding or the like.

[0185] The optical filter may have one resin film layer or two or more resin films. When the optical filter has two or more resin films, the layers may have the same or different configurations.

[0186] When the substrate has a single layer structure (resin substrate) made of a resin film containing a dye (IR), the thickness of the resin film is preferably 20 to 150 μm. When the substrate has a multilayer structure (composite substrate) having a support and a resin film containing a dye (IR) laminated on at least one main surface of the support, the thickness of the resin film is preferably 0.3 to 20 μm. When the optical filter has two or more resin films, the total thickness of the resin films is preferably within the above range.

[0187] The shape of the substrate is not particularly limited, and may be a block, plate, or film. Furthermore, the thickness of the substrate is preferably 300 μm or less from the viewpoints of reducing warpage during the formation of the dielectric multilayer film and reducing the height of the optical element. When the substrate is a resin substrate made of a resin film, the thickness is preferably 50 to 300 μm, and when the substrate is a composite substrate comprising a support and a resin film, the thickness is preferably 50 to 300 μm.

[0188] The filter may also include other components, such as a component (layer) that provides absorption by inorganic fine particles that control the transmission and absorption of light in a specific wavelength range. Specific examples of inorganic fine particles include ITO (indium tin oxide), ATO (antimony-doped tin oxide), cesium tungstate, and lanthanum boride. ITO fine particles and cesium tungstate fine particles have high transmittance for visible light and absorb light over a wide range of infrared wavelengths exceeding 1200 nm, and therefore can be used when blocking such infrared light is required. [Example]

[0189] Next, the present invention will be explained more specifically with reference to examples. Each optical property was measured using an ultraviolet-visible spectrophotometer (UH-4150, manufactured by Hitachi High-Technologies Corporation). Unless the angle of incidence is specifically stated, the spectral characteristics are values ​​measured at an angle of incidence of 0 degrees (perpendicular to the main surface of the optical filter).

[0190] The dyes used in each example are as follows: Compound 1 (squarylium dye): synthesized based on US Pat. No. 5,543,086. Compound 2 (squarylium dye): Synthesized based on WO 2017 / 135359. Compound 3 (cyanine dye): Synthesized based on Dyes and pigments 73 (2007) 344-352. Compound 4 (cyanine dye): Synthesized based on Dyes and pigments 73 (2007) 344-352. Compound 5 (diimmonium dye): Synthesized based on JP 2014-25016 A. Compound 6 (squarylium dye): Synthesized based on WO 2019 / 230660. Compound 7 (merocyanine compound): Synthesized with reference to Japanese Patent No. 6504176. Compound 8 (merocyanine compound): Synthesized with reference to Japanese Patent No. 6504176. Compound 9 (squarylium dye): synthesized based on the specifications of U.S. Patent Application Publication No. 2014 / 0061505 and WO 2014 / 088063. Compound 10 (cyanine dye): Synthesized based on Dyes and pigments 73 (2007) 344-352.

[0191] [ka]

[0192] [ka]

[0193] [ka]

[0194] <Spectral characteristics of dyes> A polyimide resin (C-3G30G manufactured by Mitsubishi Gas Chemical Company, Ltd.) was dissolved in an organic solvent (cyclohexanone:γ-butyrolactone=1:1 mass ratio) at a concentration of 8.5 mass %. To the polyimide resin solution prepared above, each dye compound shown in the table below was added so that the total amount was 7.5 parts by mass per 100 parts by mass of the resin, and the mixture was stirred for 2 hours while heating to 50° C. The dye-containing resin solution was applied to a glass substrate (alkali glass, D263 manufactured by Schott) using a spin coater, and then dried to obtain a resin film (coated film) with a thickness of 2 μm. The transmission and reflection spectra of this resin film were measured using a spectrophotometer in the wavelength range of 350 nm to 1200 nm at an angle of 5° relative to the incident direction. The obtained spectral transmittance curve and spectral reflectance curve were used to calculate the spectral internal transmittance curve, which was normalized so that the transmittance at the maximum absorption wavelength was 10%. The spectral characteristics are shown in the table below.

[0195] [Table 5]

[0196] <Examples 1-1 to 1-12: Spectral characteristics of resin films> A polyimide resin (C-3G30G manufactured by Mitsubishi Gas Chemical Company, Ltd.) was dissolved in an organic solvent (cyclohexanone:γ-butyrolactone=1:1 mass ratio) at a concentration of 8.5 mass %. Each compound was added to the polyimide resin solution prepared above so that the content (parts by mass) of each compound was as shown in the table below relative to 100 parts by mass of the resin, and the mixture was stirred for 2 hours while heating to 50° C. The dye-containing resin solution was applied to a glass substrate (alkali glass, D263 manufactured by Schott) using a spin coater, and then dried to obtain a resin film (coated film) with a thickness of 2 μm. The resin film was measured for transmission spectroscopy and reflection spectroscopy using a spectrophotometer in the wavelength range of 350 nm to 1200 nm at an incident direction of 5 degrees relative to the incident direction. The spectral characteristics are shown in the table below. Examples 1-1 to 1-12 are reference examples.

[0197] [Table 6]

[0198] The resin films of Examples 1-3, 1-5, 1-11, and 1-12, which used a balanced combination of three NIR dyes with maximum absorption wavelengths in the 680-800 nm range, were found to have excellent transmittance in the visible light range and excellent light-blocking properties in the 700-760 nm range. In order to block light over a wide range of 700-760 nm while maintaining transmittance in the visible light range, it is preferable to use a balanced combination of three or more NIR dyes with maximum absorption wavelengths in the 680-800 nm range. The resin films of Examples 1-7, 1-8, 1-9, and 1-10, which used two NIR dyes with maximum absorption wavelengths in the range of 680 to 800 nm and one NIR dye in the range of 800 nm or more, showed reduced transmittance in the visible light region. In the resin film of Example 1-6, in which the amount of NIR dye added was increased in order to achieve light-blocking properties with only one type of NIR dye, the transmittance in the visible light region decreased.

[0199] <Example 2-1 to Example 2-2: Spectral characteristics of dielectric multilayer films> We designed a reflective layer consisting of dielectric multilayer film 1 or 2, which is made by alternately laminating TiO2 and SiO2 films. The number of layers, thickness, and spectral characteristics are shown in the table below. The spectral transmittance curves of the dielectric multilayer film 1 and the dielectric multilayer film 2 are shown in FIGS. 5 and 6, respectively. It should be noted that Examples 2-1 and 2-2 are reference examples.

[0200] [Table 7]

[0201] <Example 3-1: Optical characteristics of optical filters> An optical filter was obtained by stacking, in this order, the dielectric multilayer film 1 prepared in Example 2-1, a glass substrate (alkali glass, D263 manufactured by Schott), the resin film of Example 1-1, and a seven-layer anti-reflection film formed by alternately depositing SiO2 and TiO2. The resulting optical filter was subjected to measurement of transmission spectrum at incident angles of 0°, 30°, and 70° using a spectrophotometer. To evaluate flare and ghosting, the optical filter placed on the sensor of a commercially available digital camera (Sony Cyber ​​Shot DSC-HX5) was removed, and the optical filter prepared in Example 3-1 was placed thereon. An image was taken with a white light source (tungsten halogen light source through bandpass filters (750 nm ± 20 nm, 800 nm ± 20 nm, 850 nm ± 20 nm, 900 nm ± 5 nm)) at a shutter speed of 15 seconds, and the presence or absence of flare and ghosting was visually confirmed. The bandpass filter was also removed, and an image was taken with white light (all light) at a shutter speed of 0.25 seconds, and the presence or absence of flare and ghosting was visually confirmed. If flare or ghosting was not visually observed, it was rated A; if it was visually observed, it was rated B; and if it was visually observed and was particularly strong, it was rated C.

[0202] <Example 3-2 to Example 3-11> An optical filter was obtained in the same manner as in Example 3-1, except that the resin film was changed to one shown in the table below.

[0203] <Example 3-12> An optical filter was obtained in the same manner as in Example 3-1, except that fluorophosphate glass (NF50T manufactured by AGC) was used as the glass substrate and the resin film was one shown in the table below.

[0204] <Example 3-13> An optical filter was obtained in the same manner as in Example 3-1, except that the dielectric multilayer film 1 was replaced with the dielectric multilayer film 2 prepared in Example 2-2.

[0205] The results of the spectral characteristics and flare and ghost evaluation are shown in the table below. 7 and 8 show the spectral transmittance curves of the optical filter of Example 3-11 and the optical filter of Example 3-13, respectively. Examples 3-3, 3-5, 3-11, and 3-12 are working examples, and Examples 3-1, 3-2, 3-4, 3-6 to 3-10, and 3-13 are comparative examples.

[0206] [Table 8]

[0207] The above results show that the optical filters of Examples 3-3, 3-5, 3-11, and 3-12 did not cause light leakage in the 700 to 900 nm range even at high incident angles, and exhibited high transmittance in the visible light range.Furthermore, the occurrence of flare and ghosting was suppressed. The optical filters of Examples 3-1, 3-2, 3-4, and 3-7 to 3-10 showed poor light blocking properties in the wavelength region of 700 to 760 nm. The optical filter of Example 3-6 resulted in low visible light transmittance. The optical filter of Example 3-13 had low light blocking properties in the wavelength range of 700 to 900 nm, and light leakage occurred in the wavelength range of 760 to 900 nm at a high incident angle of 70 degrees, resulting in flare and ghosting.

[0208] Although the present invention has been described in detail and with reference to specific embodiments, it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the spirit and scope of the present invention. This application is based on a Japanese patent application (Patent Application No. 2020-176883) filed on October 21, 2020, the contents of which are incorporated herein by reference. [Industrial Applicability]

[0209] The optical filter of the present invention has excellent visible light transmittance and good near-infrared light blocking properties, in which the decrease in near-infrared light blocking properties at high incident angles is suppressed, and is useful for applications in information acquisition devices, such as cameras and sensors for transportation aircraft, which have been increasingly sophisticated in recent years. [Explanation of symbols]

[0210] 1A, 1B, 1C, 1D...optical filter, 10...substrate, 11...support, 12...resin film, 30...dielectric multilayer film

Claims

1. An optical filter comprising a substrate and a dielectric multilayer film laminated as an outermost layer on at least one main surface side of the substrate, the substrate has a resin film containing a dye (IR) and a resin, the dye (IR) has a maximum absorption wavelength in the resin at 680 to 800 nm, the optical filter satisfies all of the following spectral characteristics (i-1) to (i-23), The dye (IR) is a compound (A) having a maximum absorption wavelength in the resin at a wavelength of 680 nm or more and less than 720 nm; a compound (B) having a maximum absorption wavelength in the resin at a wavelength of 720 nm or more and less than 740 nm; The compound (C) has a maximum absorption wavelength in the resin of 740 nm or more and 780 nm or less, The optical filter, wherein the compound (A), the compound (B), and the compound (C) are each selected from a squarylium dye or a cyanine dye. Spectral characteristics (i-1) to (i-9) in the spectral transmittance curve at an incident angle of 0 degrees: (i-1) Average transmittance T at wavelengths of 440 to 490 nm ４４０－４９０（０ｄｅｇ）ＡＶＥ More than 85% (i-2) Average transmittance T at wavelengths of 490 to 560 nm ４９０－５６０（０ｄｅｇ）ＡＶＥ More than 90% (i-3) Average transmittance T at wavelengths of 560 to 590 nm ５６０－５９０（０ｄｅｇ）ＡＶＥ Over 83% (i-4) Wavelength IR50 at which transmittance is 50% （０ｄｅｇ） is in the range of 600 to 680 nm (i-5) Maximum transmittance T at wavelengths of 700 to 760 nm ７００－７６０（０ｄｅｇ）ＭＡＸ is less than 2% (i-6) Transmittance T at a wavelength of 750 nm ７５０（０ｄｅｇ） is 0.5% or less (i-7) Maximum transmittance T at wavelengths of 760 to 800 nm ７６０－８００（０ｄｅｇ）ＭＡＸ is less than 1% (i-8) Maximum transmittance T at wavelengths of 800 to 900 nm ８００－９００（０ｄｅｇ）ＭＡＸ is less than 1% (i-9) Maximum transmittance T at wavelengths of 900 to 1100 nm ９００－１１００（０ｄｅｇ）ＭＡＸ is less than 1% Spectral characteristics (i-10) to (i-18) in the spectral transmittance curve at an incident angle of 30 degrees: (i-10) Average transmittance T at wavelengths of 440 to 490 nm ４４０－４９０（３０ｄｅｇ）ＡＶＥ Over 84% (i-11) Average transmittance T at wavelengths of 490 to 560 nm ４９０－５６０（３０ｄｅｇ）ＡＶＥ More than 90% (i-12) Average transmittance T at wavelengths of 560 to 590 nm ５６０－５９０（３０ｄｅｇ）ＡＶＥ Over 83% (i-13) Wavelength IR50 at which transmittance is 50% （３０ｄｅｇ） is in the range of 600 to 680 nm (i-14) Maximum transmittance T at wavelengths of 700 to 760 nm ７００－７６０（３０ｄｅｇ）ＭＡＸ is less than 2% (i-15) Transmittance T at a wavelength of 750 nm ７５０（３０ｄｅｇ） is 0.5% or less (i-16) Maximum transmittance T at wavelengths of 760 to 800 nm ７６０－８００（３０ｄｅｇ）ＭＡＸ is less than 1% (i-17) Maximum transmittance T at wavelengths of 800 to 900 nm ８００－９００（３０ｄｅｇ）ＭＡＸ is less than 1% (i-18) Maximum transmittance T at wavelengths of 900 to 1100 nm ９００－１１００（３０ｄｅｇ）ＭＡＸ is less than 5% (i-19) The wavelength IR50 （０ｄｅｇ） and the wavelength IR50 （３０ｄｅｇ） The absolute value of the difference is 8 nm or less Spectral characteristics (i-20) to (i-23) in the spectral transmittance curve at an incident angle of 70 degrees: (i-20) Maximum transmittance T at wavelengths of 700 to 760 nm ７００－７６０（７０ｄｅｇ）ＭＡＸ is 1.5% or less (i-21) Transmittance T at a wavelength of 750 nm ７５０（７０ｄｅｇ） is 1.5% or less (i-22) Maximum transmittance T at wavelengths of 760 to 800 nm ７６０－８００（７０ｄｅｇ）ＭＡＸ is 1.5% or less (i-23) Maximum transmittance T at wavelengths of 800 to 900 nm ８００－９００（７０ｄｅｇ）ＭＡＸ is 1.5% or less

2. the resin film further contains a dye (U) having a maximum absorption wavelength in the resin of 370 to 430 nm; 2. The optical filter according to claim 1, wherein the optical filter further satisfies the following spectral characteristic (i-24): (i-24) The wavelength UV at which the transmittance is 50% in the spectral transmittance curve at a wavelength of 400 to 440 nm and an incident angle of 0 degrees is called UV50 （０ｄｅｇ） The wavelength UV at which the transmittance is 50% in the spectral transmittance curve at a wavelength of 400 to 440 nm and an incident angle of 30 degrees is defined as UV50. （３０ｄｅｇ） When The wavelength UV50 （０ｄｅｇ） and the wavelength UV50 （３０ｄｅｇ） The absolute value of the difference is 5 nm or less

3. 3. The optical filter according to claim 1, wherein the resin film satisfies all of the following spectral characteristics (ii-1) to (ii-4): (ii-1) Average internal transmittance T in the spectral transmittance curve at wavelengths of 440 to 490 nm ４４０－４９０ＡＶＥ Over 84% (ii-2) Average internal transmittance T in the spectral transmittance curve at wavelengths of 490 to 560 nm ４９０－５６０ＡＶＥ Over 94% (ii-3) Average internal transmittance T in the spectral transmittance curve at wavelengths of 560 to 590 nm ５６０－５９０ＡＶＥ More than 80% (ii-4) Maximum internal transmittance T in the spectral transmittance curve at wavelengths of 700 to 760 nm ７００－７６０ＭＡＸ is less than 5%

4. 4. The optical filter according to claim 1, wherein the resin film further satisfies the following spectral characteristic (ii-5): (ii-5) Maximum internal transmittance T in the spectral transmittance curve at wavelengths of 760 to 800 nm ７６０－８００ＭＡＸ is less than 15%

5. The optical filter according to any one of claims 1 to 4, wherein the dye (IR) satisfies all of the following spectral characteristics (iii-1) to (iii-3) in a spectral transmittance curve of a coating film obtained by dissolving the dye (IR) in the resin and coating the resulting solution on an alkali glass plate so that the transmittance at the maximum absorption wavelength is 10%: (iii-1) Average internal transmittance T in the spectral transmittance curve at wavelengths of 440 to 490 nm ４４０－４９０ＡＶＥ Over 94% (iii-2) Average internal transmittance T in the spectral transmittance curve at wavelengths of 490 to 560 nm ４９０－５６０ＡＶＥ Over 94% (iii-3) Average internal transmittance T in the spectral transmittance curve at wavelengths of 560 to 590 nm ５６０－５９０ＡＶＥ Over 94%

6. 6. The optical filter according to claim 1, wherein the dye (IR) contains three or more compounds having a maximum absorption wavelength in the range of 680 to 800 nm in the resin.

7. The optical filter of claim 2 , wherein the dye (U) comprises a merocyanine dye.

8. 8. The optical filter according to claim 1, wherein the dielectric multilayer film satisfies all of the following spectral characteristics (iv-1) to (iv-12): Spectral characteristics (iv-1) to (iv-6) in the spectral transmittance curve at an incident angle of 0 degrees: (iv-1) Average transmittance T at wavelengths of 440 to 490 nm ４４０－４９０（０ｄｅｇ）ＡＶＥ More than 90% (iv-2) Average transmittance T at wavelengths of 490 to 560 nm ４９０－５６０（０ｄｅｇ）ＡＶＥ More than 90% (iv-3) Average transmittance T at wavelengths of 560 to 590 nm ５６０－５９０（０ｄｅｇ）ＡＶＥ More than 90% (iv-4) The shortest wavelength IR50 at which the transmittance is 50% after 600 nm （０ｄｅｇ） is in the range of 630 to 730 nm (iv-5) Maximum transmittance T at wavelengths of 700 to 760 nm ７００－７６０（０ｄｅｇ）ＭＡＸ More than 25% (iv-6) Maximum transmittance T at wavelengths of 760 to 900 nm ７６０－９００（０ｄｅｇ）ＭＡＸ is less than 2% Spectral characteristics (iv-7) to (iv-12) in the spectral transmittance curve at an incident angle of 30 degrees: (iv-7) Average transmittance T at wavelengths of 440 to 490 nm ４４０－４９０（３０ｄｅｇ）ＡＶＥ More than 90% (iv-8) Average transmittance T at wavelengths of 490 to 560 nm ４９０－５６０（３０ｄｅｇ）ＡＶＥ More than 90% (iv-9) Average transmittance T at wavelengths of 560 to 590 nm ５６０－５９０（３０ｄｅｇ）ＡＶＥ More than 90% (iv-10) The shortest wavelength IR50 at which the transmittance is 50% at wavelengths of 600 nm or more （３０ｄｅｇ） is in the range of 630 to 730 nm (iv-11) Maximum transmittance T at wavelengths of 700 to 760 nm ７００－７６０（３０ｄｅｇ）ＭＡＸ More than 25% (iv-12) Maximum transmittance T at wavelengths of 760 to 900 nm ７６０－９００（３０ｄｅｇ）ＭＡＸ is less than 2%

9. The optical filter according to any one of claims 1 to 8, wherein the substrate includes a support and the resin film, the resin film is laminated on at least one main surface of the support, and the support includes phosphate glass or fluorophosphate glass.

10. 10. The optical filter according to claim 1, wherein the resin is a transparent resin.

11. 11. The optical filter according to claim 1, wherein the resin is a polyimide resin.

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