WO2022034739A1 - Optical filter - Google Patents

Abstract

The present invention relates to an optical filter comprising a base material and a dielectric multilayer film laminated as an outermost layer on at least one main surface side of the base material, wherein the base material has a resin layer including a resin and dye A having an absorption maximum wavelength in a wavelength range of 400 nm or more and less than 700 nm, and has a maximum value in a wavelength range of 430 nm or more and less than 490 nm, a wavelength range of 490 nm or more and less than 590 nm, and a wavelength range of 590 nm or more and less than 650 nm.

Description

Optical filter

The present invention relates to an optical filter.

An image sensor using a solid-state image sensor has optics that transmit light in the visible band (visible light) and block light in the near-infrared region (near-infrared light) in order to reproduce color tones well and obtain clear images. A filter is used. As an optical filter, for example, a near-infrared light cut filter in which a base material containing a dye and a resin and a dielectric multilayer film is provided on a glass substrate is known.

The dye used in the optical filter is preferably a near-infrared absorbing dye having excellent light-shielding properties for near-infrared light from the viewpoint of suppressing flare phenomenon and ghost phenomenon. Further, in recent years, there has been a demand for an optical filter that selectively transmits light in a plurality of bands (for example, RGB band (red band, green band, blue band)).

As an optical filter that selectively transmits light in a plurality of bands, for example, in Patent Document 1, the number of layers having at least a layer made of resin A (layer A) and a layer made of resin B (layer B) is 30 or more. There is disclosed an optical filter comprising the laminated film of the above, having an average reflectance of 60% or more in the near infrared band having a wavelength of 850 to 1000 nm, and satisfying the following formulas a and b.

T (630 nm) -T (595 nm) ≧ 20% Equation a
T (370 nm) ≤ 5% Equation b
Here T (xnm): Transmittance at wavelength xnm

Japanese Patent Application Laid-Open No. 2006-126315

However, according to the study by the present inventors, although the optical filter described in Patent Document 1 transmits light in a plurality of bands, the selectivity of light in the RGB band is small and there is room for improvement.

The present invention has been made in view of the above-mentioned conventional circumstances, and it should be solved to provide an optical filter that selectively transmits light in the RGB band and has a small change in the amount of light in the RGB band depending on the incident angle. Make it an issue.

The optical filter according to one aspect of the present invention is as follows.
An optical filter comprising a base material and a dielectric multilayer film laminated as an outermost layer on at least one main surface side of the base material.
The base material has a resin layer containing a resin and a dye A, and has a resin layer.
The dye A has an absorption maximum wavelength in a wavelength range of 400 nm or more and less than 700 nm in the spectral transmittance curve of the coating film obtained by dissolving the dye A in the resin and applying the dye A on a glass substrate.
An optical filter that satisfies all of the following (i-1) to (i-9).
(I-1) In the spectral transmittance curve with an incident angle of 0 °,
It has a maximum value of 1 _{(0 deg)} in the wavelength range of 430 nm or more and less than 490 nm.
It has a maximum value of 2 _{(0 deg)} in the wavelength range of 490 nm or more and less than 590 nm.
It has a maximum value of 3 _{(0 deg)} in the wavelength range of 590 nm or more and less than 650 nm.
(I-2) In the spectral transmittance curve with an incident angle of 30 °,
It has a maximum value of 1 _{(30 deg)} in the wavelength range of 430 nm or more and less than 490 nm.
It has a maximum value of 2 _{(30 deg)} in the wavelength range of 490 nm or more and less than 590 nm.
It has a maximum value of 3 _{(30 deg)} in the wavelength range of 590 nm or more and less than 650 nm.
(I-3) In the spectral transmittance curve with an incident angle of 0 °, the wavelength range is a minimum value of 1 _{(0 deg)} or a transmittance of 1% or less in a wavelength range of 440 nm or more and less than 550 nm.
It has a minimum value of 2 _{(0 deg)} or a wavelength range in which the transmittance is 1% or less in a wavelength range of 490 nm or more and less than 610 nm.
(I-4) In the spectral transmittance curve with an incident angle of 30 °, the wavelength range is a minimum value of 1 _{(30 deg)} or a transmittance of 1% or less in a wavelength range of 440 nm or more and less than 550 nm.
It has a minimum value of 2 _{(30 deg)} or a wavelength range in which the transmittance is 1% or less in a wavelength range of 490 nm or more and less than 610 nm.
(I-5) All of the following equations are satisfied.
Maxima 1 _(0deg) -Maximum 1 _(0deg) ≧ 30%
Maxima 2 _(0deg) -Maximum 1 _(0deg) ≧ 30%
Maxima 2 _(0deg) -Maximum 2 _(0deg) ≧ 30%
Maxima 3 _(0deg) -Maximum 2 _(0deg) ≧ 27%
(I-6) All of the following equations are satisfied.
Maxima 1 _(30deg) -Maximum 1 _(30deg) ≧ 30%
Maxima 2 _(30deg) -Maximum 1 _(30deg) ≧ 30%
Maxima 2 _(30deg) -Maximum 2 _(30deg) ≧ 30%
Maxima 3 _(30deg) -Maximum 2 _(30deg) ≧ 27%
(I-7) In the spectral transmittance curve with an incident angle of 0 °,
The average transmittance _{(0 deg)} in the wavelength range of 700 to 1000 nm is 5% or less.
(I-8) In the spectral transmittance curve with an incident angle of 30 °,
The average transmittance _{(30 deg)} in the wavelength range of 700 to 1000 nm is 5% or less.
(I-9) All of the following equations are satisfied.
0.85 ≤ maximum value 1 ₍₃₀ deg) / maximum value 1 _{(0 deg)} ≤ 1.12
0.85 ≤ maximum value 2 ₍₃₀ deg) / maximum value 2 _{(0 deg)} ≤ 1.12
0.85 ≤ maximum value 3 ₍₃₀ deg) / maximum value 3 _{(0 deg)} ≤ 1.12

The optical filter of the present invention selectively transmits light in the RGB band, and the change in the amount of light in the RGB band due to the incident angle is small.

FIG. 1 is a cross-sectional view schematically showing an example of an optical filter of one embodiment. FIG. 2 is a diagram showing a spectral transmittance curve of the coated film of Test Example 4-2.

Hereinafter, embodiments of the present invention will be described.
In the present specification, the near-infrared absorbing dye may be abbreviated as "NIR dye" and the ultraviolet absorbing dye may be abbreviated as "UV dye".
In the present specification, the compound represented by the formula (1) is also referred to as a compound (1). The same applies to compounds represented by other formulas. Further, the group represented by the formula (1) is also referred to as a group (1), and the same applies to the groups represented by other formulas.

In the present specification, the "internal transmittance" is a transmittance obtained by subtracting the influence of interfacial reflection from the actually measured transmittance, which is represented by the formula {measured transmittance / (100-reflectance)} × 100. ..
In the present specification, the transmittance of the base material or the resin layer is "internal transmittance" even when it is described as "transmittance". On the other hand, the transmittance measured by dissolving the dye in a solvent such as dichloromethane and the transmittance of the optical filter are actually measured transmittances.

In the present specification, for a specific wavelength range, for example, a transmittance of 90% or more means that the transmittance does not fall below 90% in the entire wavelength range, that is, the minimum transmittance is 90% or more in the wavelength range. To say. Similarly, for a specific wavelength range, for example, a transmittance of 1% or less means that the transmittance does not exceed 1% in the entire wavelength range, that is, the maximum transmittance is 1% or less in the wavelength range. .. The same applies to the internal transmittance. The average transmittance and the average internal transmittance in a specific wavelength range are arithmetic means of the transmittance and the internal transmittance for each 1 nm in the wavelength range.
In the present specification, "-" representing a numerical range includes an upper and lower limit.

[Optical filter]
As shown in FIG. 1, the optical filter 10 of the embodiment of the present invention includes a base material 11 and a dielectric multilayer film 12 laminated as an outermost layer on at least one main surface side of the base material 11. The base material has a resin layer containing a resin and a dye A.
Hereinafter, the optical filter according to the embodiment of the present invention may be referred to as "the present filter".

This filter satisfies all of the following (i-1) to (i-9).
(I-1) In the spectral transmittance curve with an incident angle of 0 °,
It has a maximum value of 1 _{(0 deg)} in the wavelength range of 430 nm or more and less than 490 nm.
It has a maximum value of 2 _{(0 deg)} in the wavelength range of 490 nm or more and less than 590 nm.
It has a maximum value of 3 _{(0 deg)} in the wavelength range of 590 nm or more and less than 650 nm.
(I-2) In the spectral transmittance curve with an incident angle of 30 °,
It has a maximum value of 1 _{(30 deg)} in the wavelength range of 430 nm or more and less than 490 nm.
It has a maximum value of 2 _{(30 deg)} in the wavelength range of 490 nm or more and less than 590 nm.
It has a maximum value of 3 _{(30 deg)} in the wavelength range of 590 nm or more and less than 650 nm.
(I-3) In the spectral transmittance curve with an incident angle of 0 °, the wavelength range is a minimum value of 1 _{(0 deg)} or a transmittance of 1% or less in a wavelength range of 440 nm or more and less than 550 nm.
It has a minimum value of 2 _{(0 deg)} or a wavelength range in which the transmittance is 1% or less in a wavelength range of 490 nm or more and less than 610 nm.
(I-4) In the spectral transmittance curve with an incident angle of 30 °, the wavelength range is a minimum value of 1 _{(30 deg)} or a transmittance of 1% or less in a wavelength range of 440 nm or more and less than 550 nm.
It has a minimum value of 2 _{(30 deg)} or a wavelength range in which the transmittance is 1% or less in a wavelength range of 490 nm or more and less than 610 nm.
(I-5) All of the following equations are satisfied.
Maxima 1 _(0deg) -Maximum 1 _(0deg) ≧ 30%
Maxima 2 _(0deg) -Maximum 1 _(0deg) ≧ 30%
Maxima 2 _(0deg) -Maximum 2 _(0deg) ≧ 30%
Maxima 3 _(0deg) -Maximum 2 _(0deg) ≧ 27%
(I-6) All of the following equations are satisfied.
Maxima 1 _(30deg) -Maximum 1 _(30deg) ≧ 30%
Maxima 2 _(30deg) -Maximum 1 _(30deg) ≧ 30%
Maxima 2 _(30deg) -Maximum 2 _(30deg) ≧ 30%
Maxima 3 _(30deg) -Maximum 2 _(30deg) ≧ 27%
(I-7) In the spectral transmittance curve with an incident angle of 0 °,
The average transmittance _{(0 deg)} in the wavelength range of 700 to 1000 nm is 5% or less.
(I-8) In the spectral transmittance curve with an incident angle of 30 °,
The average transmittance _{(30 deg)} in the wavelength range of 700 to 1000 nm is 5% or less.
(I-9) All of the following equations are satisfied.
0.85 ≤ maximum value 1 ₍₃₀ deg) / maximum value 1 _{(0 deg)} ≤ 1.12
0.85 ≤ maximum value 2 ₍₃₀ deg) / maximum value 2 _{(0 deg)} ≤ 1.12
0.85 ≤ maximum value 3 ₍₃₀ deg) / maximum value 3 _{(0 deg)} ≤ 1.12

This filter can selectively transmit light in the RGB band by satisfying the above (i-1) to (i-6).

In (i-1)
The wavelength range of the maximum value 1 _{(0 deg)} is preferably 430 nm or more and less than 480 nm, and more preferably 430 nm or more and less than 455 nm.
The wavelength range of the maximum value 2 _{(0 deg)} is preferably 490 nm or more and less than 550 nm, and more preferably 500 nm or more and less than 540 nm.
The wavelength range of the maximum value 3 _{(0 deg)} is preferably 590 nm or more and less than 640 nm, and more preferably 590 nm or more and less than 630 nm.

In (i-2)
The wavelength range of the maximum value 1 _{(30 deg)} is preferably 430 nm or more and less than 480 nm, and more preferably 430 nm or more and less than 455 nm.
The wavelength range of the maximum value 2 _{(30 deg)} is preferably 490 nm or more and less than 550 nm, and more preferably 500 nm or more and less than 540 nm.
The wavelength range of the maximum value 3 _{(30 deg)} is preferably 590 nm or more and less than 640 nm, and more preferably 590 nm or more and less than 630 nm.

In (i-3)
The wavelength range of the minimum value 1 _{(0 deg)} or the wavelength range in which the transmittance is 1% or less is preferably 450 nm or more and less than 540 nm, and more preferably 460 nm or more and less than 530 nm.
The wavelength range of the minimum value 2 _{(0 deg)} or the wavelength range in which the transmittance is 1% or less is preferably 500 nm or more and less than 600 nm, and more preferably 510 nm or more and less than 590 nm.

In (i-4)
The wavelength range of the minimum value 1 _{(30 deg)} or the wavelength range in which the transmittance is 1% or less is preferably 400 nm or more and less than 430 nm, and more preferably 410 nm or more and less than 420 nm.
The wavelength range of the minimum value 2 _{(30 deg)} or the wavelength range in which the transmittance is 1% or less is preferably 450 nm or more and less than 530 nm, and more preferably 460 nm or more and less than 520 nm.

In (i-5)
The maximum value 1 _{(0 deg) -minimum} value 1 _{(0 deg)} is preferably 35% or more, more preferably 40% or more.
The maximum value 2 _{(0 deg)} -minimum value 1 _{(0 deg)} is preferably 32% or more, more preferably 35% or more.
The maximum value 2 _{(0 deg) -minimum} value 2 _{(0 deg)} is preferably 32% or more, more preferably 35% or more.
The maximum value 3 _{(0 deg)} -minimum value 2 _{(0 deg)} is preferably 30% or more, more preferably 35% or more.

In (i-6)
The maximum value 1 _{(30 deg) -minimum} value 1 _{(30 deg)} is preferably 35% or more, more preferably 40% or more.
The maximum value 2 _{(30 deg) -minimum value 1 (30 deg)} is preferably 32% or more, more preferably 35% or more.
The maximum value 2 _{(30 deg) -minimum} value 2 _{(30 deg)} is preferably 32% or more, more preferably 35% or more.
The maximum value 3 _{(30 deg) -minimum value 2 (30 deg)} is preferably 30% or more, more preferably 35% or more.

This filter is excellent in light-shielding property of near-infrared light by satisfying the above (i-7) to (i-8).

In (i-7)
The average transmittance _{(0 deg)} is preferably 2% or less, more preferably 0.5% or less, still more preferably 0.2% or less.

In (i-8)
The average transmittance _{(30 deg)} is preferably 1% or less, more preferably 0.5% or less, still more preferably 0.2% or less.

By satisfying the above (i-9), this filter reduces the change in the amount of light in the RGB band due to the incident angle.

In (i-9)
The maximum value 1 _{(30 deg)} / maximum value 1 _{(0 deg)} is preferably 0.9 or more and 1.12 or less, and more preferably 0.95 or more and 1.05 or less.
The maximum value 2 _{(30 deg)} / maximum value 2 _{(0 deg)} is preferably 0.9 or more and 1.12 or less, and more preferably 0.95 or more and 1.05 or less.
The maximum value 3 _{(30 deg)} / maximum value 3 _{(0 deg)} is preferably 0.9 or more and 1.12 or less, and more preferably 0.95 or more and 1.05 or less.

Further, it is preferable that this filter satisfies all of the following equations.
| Wavelength λ1 _{(0 deg) -Wavelength λ1 (30} deg) | ≤10 nm
| Wavelength λ2 _{(0 deg) -Wavelength λ2 (30} deg) | ≤10 nm
| Wavelength λ3 _{(0 deg) -Wavelength λ3 (30} deg) | ≤10 nm
| Wavelength λ4 _{(0 deg)} -Wavelength λ4 ₍₃₀ deg) | ≤10 nm

<In the formula, wavelength λ1 _(0deg) , wavelength λ1 _(30deg) , wavelength λ2 _(0deg) , wavelength λ2 _(30deg) , wavelength λ3 _(0deg) , wavelength λ3 _(30deg) , wavelength λ4 _(0deg) , wavelength λ4 ₍ 30deg). ₎ Is a value obtained by the following formula.
Wavelength λ1 _(0deg) = {wavelength at maximum value 1 _(0deg) + wavelength at minimum value 1 _(0deg) } ÷ 2
Wavelength λ1 _(30deg) = {wavelength at maximum value 1 _(30deg) + wavelength at minimum value 1 _(30deg) } / 2
Wavelength λ2 _(0deg) = {wavelength at maximum value 2 _(0deg) + wavelength at minimum value 1 _(0deg) } ÷ 2
Wavelength λ2 _(30deg) = {wavelength at maximum value 2 _(30deg) + wavelength at minimum value 1 _(30deg) } ÷ 2
Wavelength λ3 _(0deg) = {wavelength at maximum value 2 _(0deg) + wavelength at minimum value 2 _(0deg) } ÷ 2
Wavelength λ3 _(30deg) = {wavelength at maximum value 2 _(30deg) + wavelength at minimum value 2 _(30deg) } ÷ 2
Wavelength λ4 _(0deg) = {wavelength at maximum value 3 _(0deg) + wavelength at minimum value 2 _(0deg) } ÷ 2
Wavelength λ4 _(30deg) = {wavelength at maximum value 3 _(30deg) + wavelength at minimum value 2 _(30deg) } ÷ 2>

By satisfying the above equation, this filter reduces the change in the amount of light in the RGB band due to the incident angle.

| Wavelength λ1 _{(0 deg)} − Wavelength λ1 ₍₃₀ deg) | is preferably 5 nm or less, more preferably 3 nm or less.
| Wavelength λ2 _{(0 deg)} − Wavelength λ _{2 (30} deg) | is preferably 5 nm or less, more preferably 3 nm or less.
| Wavelength λ3 _{(0 deg)} − Wavelength λ3 ₍₃₀ deg) | is preferably 5 nm or less, more preferably 3 nm or less.
| Wavelength λ4 _{(0 deg)} − Wavelength λ4 ₍₃₀ deg) | is preferably 5 nm or less, more preferably 3 nm or less.

Further, when the resin layer in the present filter has the dye 1 described later, the dye 2 described later, the dye 3 described later, the dye 4 described later, and the resin, the filter has the following (iv-1) to (iv-4). ) Satisfy all of them.

(Iv-1) In the spectral transmittance curve of the coating film coated by dissolving the dye 1 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
IR80a _{(dye 1)} is the longest wavelength with an internal transmittance of 80% in the wavelength range of 395 nm or more and less than 450 nm.
When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 1)} , the following equation is satisfied.
IR80a _{(dye 1)} -IR10 ₍ dye 1) ≤25 nm
(Iv-2) In the spectral transmittance curve of the coating film coated by dissolving the dye 2 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
IR80a _{(dye 2)} is the longest wavelength in which the internal transmittance is 80% in the wavelength range of 450 nm or more and less than 540 nm.
The shortest wavelength at which the internal transmittance is 80% is IR80b _{(dye 2)} .
When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 2)} , the following equation is satisfied.
IR80a _{(dye 2)} -IR10 ₍ dye 2) ≤35 nm
IR80b _{(dye 2)} -IR10 ₍ dye 2) ≤55 nm
(Iv-3) In the spectral transmittance curve of the coating film coated by dissolving the dye 3 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
IR80a _{(dye 3)} is the longest wavelength in which the internal transmittance is 80% in the wavelength range of 540 nm or more and less than 600 nm.
The shortest wavelength at which the internal transmittance is 80% is IR80b _{(dye 3)} .
When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 3)} , the following equation is satisfied.
IR80a _{(dye 3)} -IR10 ₍ dye 3) ≤35 nm
IR80b _{(dye 3)} -IR10 ₍ dye 3) ≤55 nm
(Iv-4) In the spectral transmittance curve of the coating film coated by dissolving the dye 4 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
IR80b _{(dye 4)} is the shortest wavelength in which the internal transmittance is 80% in the wavelength range of 600 nm or more and less than 720 nm.
When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 4)} , the following equation is satisfied.
IR80b _{(dye 4)} -IR10 ₍ dye 4) ≤80 nm

This filter can more selectively transmit light in the RGB band by satisfying the above (iv-1) to (iv-4).

In (iv-1)
IR80a _{(dye 1)} -IR10 _{(dye 1)} is preferably 24 nm or less, more preferably 23 nm or less.

In (iv-2)
IR80a _{(dye 2)} -IR10 _{(dye 2)} is preferably 30 nm or less, more preferably 26 nm or less.
IR80b _{(dye 2)} -IR10 _{(dye 2)} is preferably 50 nm or less, more preferably 47 nm or less.

In (iv-3)
IR80a _{(dye 3)} -IR10 _{(dye 3)} is preferably 33 nm or less, more preferably 30 nm or less.
IR80b _{(dye 3)} -IR10 _{(dye 3)} is preferably 53 nm or less, more preferably 50 nm or less.

In (iv-4)
IR80b _{(dye 4)} -IR10 _{(dye 4)} is preferably 79 nm or less, more preferably 77 nm or less.

<Base material, resin layer>
The base material has a resin layer. The resin layer contains the resin and the dye A.

(resin)
The resin is preferably a transparent resin (resin having transparency).
Examples of the transparent resin include cycloolefin polymers (COP) such as norbornene resin or cycloolefin copolymers (COC); polyimide resins (PI); polycarbonate resins (PC); polyethylene terephthalates (PET) and polyester resins such as polybutylene terephthalates. Polyolefin resins such as polyethylene, polypropylene and ethylene vinyl acetate copolymers; acrylic resins such as polyacrylates and polymethylmethacrylates; urethane resins, vinyl chloride resins; fluororesins; polyvinyl butyral resins; polyvinyl alcohol resins and the like.
One of these resins may be used alone, or two or more of these resins may be mixed and used.

Among these, cycloolefin polymer, cycloolefin copolymer, polyimide resin, polycarbonate resin, polyethylene terephthalate, acrylic resin, epoxy from the viewpoint of achieving both transparency in the visible light range (wavelength 400 to 700 nm), heat resistance, and glass transition temperature. Resins are preferable, polyethylene terephthalates and polyimide resins are more preferable, and polyimide resins are even more preferable.

(Dye A)
The dye A has an absorption maximum wavelength in a wavelength range of 400 nm or more and less than 700 nm in the spectral transmittance curve of the coating film obtained by dissolving the dye A in a resin and applying the dye A on a glass substrate.

The dye A preferably contains dye 1, dye 2, dye 3 and dye 4 from the viewpoint of selectively transmitting light in the RGB band.
Further, when the dye A contains the dye 1, the dye 2, the dye 3 and the dye 4, it is preferable that all of the following (ii-1) to (ii-4) are satisfied.

(Ii-1) In the spectral transmittance curve of the coating film obtained by dissolving the dye 1 in the resin and coating it on a glass substrate, the dye 1 has an absorption maximum wavelength in a wavelength range of 395 nm or more and less than 450 nm. ..
(Ii-2) In the spectral transmittance curve of the coating film obtained by dissolving the dye 2 in the resin and coating the glass substrate, the dye 2 has an absorption maximum wavelength in a wavelength range of 450 nm or more and less than 540 nm. ..
(Ii-3) In the spectral transmittance curve of the coating film obtained by dissolving the dye 3 in the resin and coating the glass substrate, the dye 3 has an absorption maximum wavelength in a wavelength range of 540 nm or more and less than 600 nm. ..
(Ii-4) In the spectral transmittance curve of the coating film obtained by dissolving the dye 4 in the resin and coating the glass substrate, the dye 4 has an absorption maximum wavelength in a wavelength range of 600 nm or more and less than 720 nm. ..

When all of the above (ii-1) to (ii-4) are satisfied, this filter can more selectively transmit light in the RGB band.

In (ii-1), the dye 1 preferably has an absorption maximum wavelength in the wavelength range of 395 nm or more and less than 430 nm, and more preferably has an absorption maximum wavelength in the wavelength range of 395 nm or more and less than 420 nm.
In (ii-2), the dye 2 preferably has an absorption maximum wavelength in a wavelength range of 460 nm or more and less than 530 nm, and more preferably has an absorption maximum wavelength in a wavelength range of 470 nm or more and less than 520 nm.
In (ii-3), the dye 3 preferably has an absorption maximum wavelength in the wavelength range of 550 nm or more and less than 590 nm, and more preferably has an absorption maximum wavelength in the wavelength range of 560 nm or more and less than 580 nm.
In (ii-4), the dye 4 preferably has an absorption maximum wavelength in the wavelength range of 640 nm or more and less than 710 nm, and more preferably has an absorption maximum wavelength in the wavelength range of 660 nm or more and less than 710 nm.

When the resin layer has dye 1, dye 2, dye 3, dye 4, and resin, the resin layer preferably satisfies all of the following (iii-1) to (iii-3).

(Iii-1) It has a maximum value of 10 in the wavelength range of 430 nm or more and less than 490 nm, and has a maximum value of 10.
It has a maximum value of 11 in the wavelength range of 490 nm or more and less than 590 nm, and has a maximum value of 11.
It has a maximum value of 12 in the wavelength range of 590 nm or more and less than 650 nm.
(Iii-2) The wavelength range is 400 nm or more and less than 440 nm, and the minimum value is 10 or the internal transmittance is 1% or less.
It has a minimum value of 11 or a wavelength range in which the internal transmittance is 1% or less in a wavelength range of 440 nm or more and less than 540 nm.
It has a minimum value of 12 or a wavelength range in which the internal transmittance is 1% or less in a wavelength range of 540 nm or more and less than 640 nm.
It has a minimum value of 13 or a wavelength range in which the internal transmittance is 1% or less in a wavelength range of 640 nm or more and less than 700 nm.
(Iii-3) The maximum value among the maximum value 10, the maximum value 11, and the maximum value 12 is 40% or more.

When all of the above (iii-1) to (iii-3) are satisfied, this filter can more selectively transmit light in the RGB band.

In (iii-1)
The wavelength range of the maximum value 10 is preferably 430 nm or more and less than 480 nm, and more preferably 430 nm or more and less than 455 nm.
The wavelength range of the maximum value 11 is preferably 490 nm or more and less than 550 nm, and more preferably 500 nm or more and less than 540 nm.
The wavelength range of the maximum value 12 is preferably 590 nm or more and less than 640 nm, and more preferably 590 nm or more and less than 630 nm.

In (iii-2)
The wavelength range of the minimum value 10 or the wavelength range in which the internal transmittance is 1% or less is preferably 400 nm or more and less than 430 nm, and more preferably 410 nm or more and less than 420 nm.
The wavelength range of the minimum value 11 or the wavelength range in which the internal transmittance is 1% or less is preferably 450 nm or more and less than 530 nm, and more preferably 460 nm or more and less than 520 nm.
The wavelength range of the minimum value 12 or the wavelength range in which the internal transmittance is 1% or less is preferably 550 nm or more and less than 630 nm, and more preferably 560 nm or more and less than 600 nm.

In (iii-3)
The maximum value among the maximum value 10, the maximum value 11 and the maximum value 12 is preferably 55% or more, more preferably 60% or more.

(Dye 1)
The dye 1 is preferably a compound represented by the following formula (1).

In formula (1), R ¹ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent.
As the substituent, an alkoxy group, an acyl group, an acyloxy group, a cyano group, a dialkylamino group or a chlorine atom is preferable. The alkoxy group, acyl group, acyloxy group and dialkylamino group preferably have 1 to 6 carbon atoms.

Specifically, as R ¹ having no substituent, a part of the hydrogen atom may be substituted with an aliphatic ring, an aromatic ring or an alkenyl group, an alkyl group having 1 to 12 carbon atoms, and a part of the hydrogen atom. May be substituted with an aromatic ring, an alkyl group or an alkenyl group, a cycloalkyl group having 3 to 8 carbon atoms, and a part of the hydrogen atom may be substituted with an aliphatic ring, an alkyl group or an alkenyl group. An aryl group having 6 to 12 carbon atoms is preferable.

When R ¹ is an unsubstituted alkyl group, the alkyl group may be linear or branched, and the number of carbon atoms thereof is more preferably 1 to 6.

When R ¹ is an alkyl group having 1 to 12 carbon atoms in which a part of the hydrogen atom is substituted with an aliphatic ring, an aromatic ring or an alkenyl group, 1 to 1 to 12 carbon atoms having a cycloalkyl group having 3 to 6 carbon atoms. An alkyl group of 4 and an alkyl group having 1 to 4 carbon atoms substituted with a phenyl group are more preferable, and an alkyl group having 1 or 2 carbon atoms substituted with a phenyl group is particularly preferable. The alkyl group substituted with an alkenyl group means an alkenyl group as a whole but does not have an unsaturated bond between the 1st and 2nd positions, and refers to, for example, an allyl group, a 3-butenyl group, or the like.

Preferred R ¹ is an alkyl group having 1 to 6 carbon atoms in which a part of the hydrogen atom may be substituted with a cycloalkyl group or a phenyl group. Particularly preferable Q 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. Be done.

In the formula (1), R ² to R ⁵ independently represent 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.

Examples of the halogen atom include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like.

The number of carbon atoms of the alkyl group and the alkoxy group is preferably 1 to 6, and more preferably 1 to 4.

At least one of R ² and R ³ is preferably an alkyl group, and it is more preferable that both are alkyl groups. When R ² and R ³ are not alkyl groups, a hydrogen atom is more preferred. As R ² and R ³ , an alkyl group having 1 to 6 carbon atoms is particularly preferable.

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

In formula (1), Y represents a methylene group or oxygen atom substituted with R ⁶ and R ⁷ .
In the formula (1), R ⁶ and R ⁷ independently represent 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.

In the formula (1), X represents any of the following formulas (X1) to (X5).

^In the formulas (X1) to ⁽ X4), R8 and R9 each independently represent a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent.
R ¹⁰ to R ¹⁹ each independently represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent.

Examples of the substituents of R ⁸ to R ¹⁹ include the same substituents as the substituents in R ¹ , and the preferred embodiments are also the same. When R ⁸ to R ¹⁹ are hydrocarbon groups having no substituent, the same embodiment as that of R ¹ having no substituent can be mentioned.

In formula (X1), R ⁸ and R ⁹ may be different groups, but the same group is preferred. When R ⁸ and R ⁹ are unsubstituted alkyl groups, they may be linear or branched, and the number of carbon atoms is more preferably 1 to 6.

Preferred R ⁸ and R ⁹ are all alkyl groups having 1 to 6 carbon atoms in which a part of the hydrogen atom may be substituted with a cycloalkyl group or a phenyl group. Particularly preferable R ⁸ and R ⁹ are all alkyl groups having 1 to 6 carbon atoms, and specifically, for example, methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group and isobutyl. Groups, t-butyl groups and the like can be mentioned.

In the formula (X2), both R ¹⁰ and R ¹¹ are more preferably alkyl groups having 1 to 6 carbon atoms, and particularly preferably the same alkyl group.

In the formula (X3), R ¹² and R ¹⁵ are preferably hydrogen atoms or alkyl groups having 1 to 6 carbon atoms having no substituent. The two groups R ¹³ and R ¹⁴ bonded to the same carbon atom are both hydrogen atoms, or an alkyl group having 1 to 6 carbon atoms is preferable.

The two groups R ¹⁶ and R ¹⁷ and R ¹⁸ and R ¹⁹ bonded to the same carbon atom in the formula (X4) are all hydrogen atoms, or an alkyl group having 1 to 6 carbon atoms is preferable.

Specific examples of the compound (1) include compounds in which the atom or group bonded to each skeleton is the atom or group shown in the table below.

(Dye 3)
The dye 3 is preferably a compound represented by the following formula (3).

In the formula (3), R ¹⁰¹ and R ¹⁰² may independently have an alkyl group which may have a substituent, an alkenyl group which may have a substituent, and a substituent. Represents an alkoxycarbonyl group or a phenyl group which may have a substituent.
n represents an integer of 0 to 3 independently.

The alkyl group may be linear or branched, preferably an alkyl group having 1 to 6 carbon atoms, and more preferably an unsubstituted alkyl group such as a methyl group, an ethyl group, a propyl group or a t-butyl group.

The alkenyl group may be linear or branched, preferably an alkenyl group having 1 to 6 carbon atoms, and more preferably an unsubstituted alkenyl group such as a vinyl group, an allyl group, or a 3-butene-1-yl group.

As the alkoxycarbonyl group, a group having an alkyl group as described above is preferable.

The substituent of the alkyl group, the alkenyl group, and the alkoxycarbonyl group is not particularly limited, and examples thereof include the alkoxy group having an alkyl group as described above, and halogen atoms such as chlorine and fluorine.

The substituent of the phenyl group is not particularly limited, but examples thereof include an alkyl group, an alkoxy group and a halogen atom as described above, and an unsubstituted phenyl group is preferable.

In equation (3), n independently represents an integer of 0 to 3. It is preferable that n is 2 to 3 independently of each other.

Further, the compound (3) may have the same group having two pyrrole rings or different groups, but preferably the group having two pyrrole rings is the same and is a symmetrical squarylium system. It is preferably a compound.

Specific examples of the compound (3) include compounds in which the atom or group bonded to each skeleton is the atom or group shown in the table below.

(Dye 4)
The dye 4 is preferably a compound represented by the following formula (4).

In formula (4), R ²¹ and R ²² each independently have a hydrogen atom, an alkyl group or an allyl group having 1 to 6 carbon atoms which may have a substituent, or a substituent. A good aryl group or alaryl group having 6 to 11 carbon atoms is shown.

R ²³ and R ²⁵ each independently represent a hydrogen atom, a halogen atom, or an alkyl group or an alkoxy group having 1 to 6 carbon atoms.

R ²⁴ and R ²⁶ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl or alkoxy group having 1 to 6 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, and -NR ²⁷ R ²⁸ .

R ²⁷ and R ²⁸ are independently each of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, -C (= O) -R ²⁹ , -NHR ³⁰ , -SO ₂ -R ³⁰ , or the following formula ( The group represented by S) is shown.

R ²⁹ may have a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 11 carbon atoms, or a substituent, and an oxygen atom between carbon atoms. Indicates an alaryl group having 7 to 18 carbon atoms which may have.

In R ³⁰ , one or more hydrogen atoms may be substituted with a halogen atom, a hydroxyl group, a carboxy group, a sulfo group, or a cyano group, and an unsaturated bond, an oxygen atom, a saturated or unsaturated group between carbon atoms. It shows a hydrocarbon group having 1 to 25 carbon atoms which may contain a ring structure.

In the formula (S), R ⁴¹ and R ⁴² each independently represent a hydrogen atom, a halogen atom, or an alkyl group or an alkoxy group having 1 to 10 carbon atoms.

K represents 2 or 3.

R ²¹ and R ²² , R ²² and R ²⁵ , and R ²¹ and R ²³ are connected to each other to form a heterocycle A, a heterocycle B, and a heterocycle C having 5 or 6 members together with a nitrogen atom, respectively. May be.

When the heterocyclic ring A is formed, R ²¹ and R ²² have a divalent group −Q— to which they are bonded, and the hydrogen atom is an alkyl group having 1 to 6 carbon atoms and an aryl group having 6 to 10 carbon atoms. Alternatively, an alkylene group or an alkyleneoxy group which may be substituted with an acyloxy group having 1 to 10 carbon atoms which may have a substituent is shown.

R ²² and R ²⁵ when the heterocycle B is formed, and R ²¹ and R ²³ when the heterocycle C is formed are the divalent groups -X ¹ -Y ^1- and X to which they are bonded, respectively. As ² -Y2- (X ¹ and X ² on the side that binds to nitrogen), X ¹ and X ² are groups represented by the following formulas (1x) or ( ^2x ), respectively, and Y ¹ and Y ² are the following, respectively. It is a group represented by any one selected from the formulas (1y) to (5y).

When X ¹ and X ² are groups represented by the following formulas (2x), Y ¹ and Y ² may be single bonds, respectively, and in that case, oxygen atoms may be provided between carbon atoms. ..

In the formula (1x), each of the four Zs independently represents 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 ³¹ to R ³⁶ independently represent 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 ³⁸ and R ³⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms.

R ²⁷ , R ²⁸ , R ²⁹ , R ³¹ to R ³⁷ , R ²¹ to R ²³ when no heterocycle is formed, and R ²⁵ are 5-membered rings coupled to any other of these. Alternatively, a 6-membered ring may be formed. R ³¹ and R ³⁶ and R ³¹ and R ³⁷ may be directly coupled.

As the compound (4), for example, a compound represented by the following formula (4-1) is preferable from the viewpoint of increasing the visible light transmittance.

The symbols in the formula (4-1) are the same as the respective provisions of the same symbols in the formula (4), and the preferred embodiments are also the same.

In compound (4-1), X ¹ is preferably a group (2x), and Y ¹ is preferably a single bond or a group (1y). In this case, as R ³¹ to R ³⁶ , a hydrogen atom or an alkyl group having 1 to 3 carbon atoms is preferable, and a hydrogen atom or a methyl group is more preferable. Specific examples of −Y ¹ − X ¹ − include divalent organic groups represented by the formulas (11-1) to (12-3).

-C (CH ₃ ) ₂ -CH (CH ₃ ) -... (11-1)
-C (CH ₃ ) ₂ -CH _2- ... (11-2)
-C (CH ₃ ) ₂ -CH (C ₂ H ₅ ) -... (11-3)
-C (CH ₃ ) ₂ -C (CH ₃ ) (nC ₃ H ₇ )-... (11-4)
-C (CH ₃ ) ₂ -CH ₂ -CH _2- ... (12-1)
-C (CH ₃ ) ₂ -CH ₂ -CH (CH ₃ ) -... (12-2)
-C (CH ₃ ) ₂ -CH (CH ₃ ) -CH _2- ... (12-3)

Further, in compound (4-1), R ²¹ is independently described below from the viewpoints of solubility, heat resistance, and steepness of change near the boundary between the visible region and the near infrared region in the spectral transmittance curve. The group represented by the formula (4-11) or the formula (4-12) is more preferable.

In formulas (4-11) and (4-12), R ⁷¹ to R ⁷⁵ independently represent a hydrogen atom, a halogen atom, or an alkyl group having 1 to 4 carbon atoms.

In compound (4-1), R ²⁴ is preferably -NH-SO ₂ -R ³⁰ from the viewpoint of increasing the transmittance of visible light, particularly the transmittance of light having a wavelength of 430 to 550 nm.

In the compound (4-1), the compound in which R ²⁴ is -NH-SO ₂ -R ³⁰ is represented by the following formula (4-1-A).

R ²³ and R ²⁶ in the compound (4-1-A) are preferably hydrogen atoms, halogen atoms, alkyl groups having 1 to 6 carbon atoms or alkoxy groups having 1 to 6 carbon atoms, respectively, and both of them are independent. Hydrogen atoms are more preferred.

In compound (4-1-A), R ³⁰ has an alkyl group having 1 to 12 carbon atoms which may have a branch and a carbon number which may have a branch, respectively, independently from the viewpoint of light resistance. Alkoxy groups of 1 to 12 or hydrocarbon groups having 6 to 16 carbon atoms having an unsaturated ring structure are preferable. Examples of the unsaturated ring structure include benzene, toluene, xylene, furan, and benzofuran. R ³⁰ is more preferably an alkyl group having 1 to 12 carbon atoms which may have a branch or an alkoxy group having 1 to 12 carbon atoms which may have a branch, respectively. In each group showing R ³⁰ , a part or all of a hydrogen atom may be substituted with a halogen atom, particularly a fluorine atom.

Specific examples of the compound (4) include compounds in which the atom or group bonded to each skeleton in the formula (4-1-A) is an atom or group shown in the table below.

(Other pigments)
The resin layer can further contain a UV dye as another dye.
Examples of UV dyes include merocyanine-based, oxazole-based, cyanine-based, naphthalimide-based, oxadiazole-based, oxazine-based, oxazolidine-based, naphthalic acid-based, styryl-based, anthracene-based, cyclic carbonyl-based, and triazole-based dyes. Can be mentioned.

(Contents of each component)
The content of the dye 1 in the base material is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin.
The content of the dye 2 in the base material is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin.
The content of the dye 3 in the base material is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin.
The content of the dye 4 in the base material is preferably 0.1 to 10 parts by mass, more preferably 0.1 to 5 parts by mass with respect to 100 parts by mass of the resin.
The content of the total dye in the base material is preferably 0.1 to 20 parts by mass, and more preferably 5 to 15 parts by mass with respect to 100 parts by mass of the resin.

(Base material composition)
The base material may have a single-layer structure or a multi-layer structure. The material of the base material may be an organic material or an inorganic material as long as it is a transparent material that transmits visible light of 400 to 700 nm, and is not particularly limited.

When the base material has a single-layer structure, the base material is preferably a resin base material containing dye A and a resin. Further, the resin base material can further contain a UV dye.
When the base material has a multi-layer structure, the base material preferably has a structure in which a resin layer containing the dye A and the resin is laminated on at least one main surface of the support. At this time, the support is preferably made of the transparent resin or the transparent inorganic material. Further, the resin layer can further contain a UV dye.

As the transparent inorganic material, glass or a crystalline material is preferable.
Examples of the glass include absorbent glass (near infrared absorber glass) containing copper ions in fluoride-based glass, phosphate-based glass and the like, soda lime glass, borosilicate glass, non-alkali glass, quartz glass and the like. .. As the glass, absorbent glass is preferable depending on the purpose, and phosphate-based glass and fluoride-based glass are preferable from the viewpoint of absorbing infrared light. When it is desired to take in a large amount of red light (600 to 700 nm), alkaline glass, non-alkali glass, and quartz glass are preferable. The "phosphate-based glass" also includes silicate glass in which a part of the skeleton of the glass is composed of SiO ₂ .

As for glass, alkali metal ions (for example, Li ion and Na ion) having a small ion radius existing on the main surface of the glass plate are converted into alkali ions having a larger ion radius (for example) by ion exchange at a temperature below the glass transition point. , Li ion is Na ion or K ion, and Na ion is K ion.) You may use the chemically strengthened glass obtained by exchanging with the ion.

Examples of the crystal material include birefringent crystals such as quartz, lithium niobate, and sapphire.

As the support, an inorganic material is preferable, and glass and sapphire are particularly preferable, from the viewpoint of shape stability related to long-term reliability such as optical properties and mechanical properties, and handleability at the time of filter manufacturing.

When the base material is a resin base material having a single-layer structure containing a transparent resin and dye A, it can be produced by, for example, the following method.

The resin base material can be produced by melt-extruding a transparent resin or a mixture of a transparent resin and an arbitrary component and molding it into a film. Further, a transparent resin and, if necessary, an arbitrary component are dissolved in a solvent to prepare a coating liquid, which is applied to a peelable base material for producing a resin base material to a desired thickness, dried, and further. After curing, if necessary, the resin base material can be peeled off from the base material for production.

The solvent used for the coating liquid may be a dispersion medium capable of stably dispersing the transparent resin or a solvent capable of dissolving the transparent resin. The coating liquid may contain a surfactant for improving voids due to minute bubbles, dents due to adhesion of foreign substances, repellency in the drying step, and the like. Further, for the coating of the coating liquid, for example, a dip coating method, a cast coating method, a die coating method, a spin coating method and the like can be used.

When the base material has a multi-layer structure having a support and a resin layer containing a dye A laminated on at least one main surface of the support, the thickness of the resin layer is preferably 0.3 to 15 μm. .. When the resin layer is composed of a plurality of layers, the total thickness of the resin layers is preferably 0.3 to 15 μm.

In the resin layer, the dye A, the resin or the raw material component of the resin, and each component to be blended as necessary are dissolved or dispersed in a solvent to prepare a coating liquid, and this is applied to the base material. It can be formed by drying and further curing if necessary. The base material may be a support included in the present filter, or may be a peelable base material used only when forming a resin layer. The solvent may be a dispersion medium that can be stably dispersed or a solvent that can be dissolved.

Further, the coating liquid may contain a surfactant for improving voids due to minute bubbles, dents due to adhesion of foreign substances, repelling in the drying process, and the like. Further, for the coating of the coating liquid, for example, a dip coating method, a cast coating method, a spin coating method or the like can be used. A resin layer is formed by applying the above coating liquid onto a substrate and then drying it. When the coating liquid contains a raw material component of a transparent resin, further curing treatment such as heat curing and photocuring is performed.

Further, the resin layer can be manufactured in the form of a film by extrusion molding, and this film may be laminated on another member and integrated by thermocompression bonding or the like. For example, this film may be attached on a support.

This filter may have one resin layer or two or more layers. When the filter has two or more resin layers, each layer may have the same configuration or may be different.

The shape of the base material is not particularly limited, and may be block-shaped, plate-shaped, or film-shaped.

When the base material has a single-layer structure, the thickness of the base material is preferably 500 μm or less, more preferably 400 μm or less, from the viewpoint of reducing the height of the filter. When the base material has a single-layer structure, the thickness of the base material is preferably 30 μm or more, more preferably 50 μm or more from the viewpoint of process handling.

When the base material has a multi-layer structure, the thickness of the base material is preferably 500 μm or less, more preferably 400 μm or less, from the viewpoint of reducing the height of the filter. When the base material has a multi-layer structure, the thickness of the base material is preferably 30 μm or more, more preferably 50 μm or more from the viewpoint of process handling.

<Dielectric multilayer film>
This filter has a dielectric multilayer film. The dielectric multilayer film is laminated as an outermost layer on at least one main surface side of the base material.

When the dielectric multilayer film is laminated as the outermost layer on both main surface sides of the substrate, at least one of the dielectric multilayer films is designed as a near-infrared reflective layer (hereinafter, also referred to as NIR reflective layer). Is preferable. The other side of the dielectric multilayer film is preferably designed as a NIR reflective layer, a reflective layer having a reflective region other than the near infrared region, or an antireflection layer.

When the base material has a single-layer structure, it is preferable to form NIR reflective layers on both sides of the base material from the viewpoint of preventing warping.

The NIR reflective layer is a dielectric multilayer film designed to shield light in the near infrared region. The NIR reflective layer has, for example, wavelength selectivity that transmits visible light and mainly reflects light in the near infrared region other than the light shielding region of the absorption layer. The reflection region of the NIR reflection layer may include a light-shielding region in the near-infrared region of the absorption layer. The NIR reflection layer is not limited to the NIR reflection characteristic, and may be appropriately designed to have specifications for further blocking light in a wavelength range other than the near infrared region, for example, the near ultraviolet region.

The NIR reflective layer is composed of, for example, a dielectric multilayer film in which a low refractive index dielectric film (low refractive index film) and a high refractive index dielectric film (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 the material of the high refractive index film include Ta ₂ O ₅ , TIO ₂ , and Nb ₂ O ₅ . Of these, TiO ₂ is preferable from the viewpoints of film formation property, reproducibility in refractive index and the like, stability and the like.

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 the material of the low refractive index film include SiO ₂ , SiO _x N _y and the like. SiO ₂ is preferable from the viewpoint of reproducibility, stability, economy and the like in terms of film forming property.

Further, it is preferable that the transmittance of the NIR reflective layer changes sharply in the boundary wavelength region between the transmissive region and the light-shielding region. For this purpose, the total number of laminated dielectric multilayer films constituting the reflective layer is preferably 15 or more, more preferably 25 or more, and even more preferably 30 or more. However, when the total number of layers increases, warpage or the like occurs or the film thickness increases. Therefore, the total number of layers is preferably 100 layers or less, more preferably 75 layers or less, and even more preferably 60 layers or less. The film thickness of the reflective layer is preferably 2 to 10 μm as a whole.

If the total number of laminated dielectric multilayer films and the film thickness are within the above range, the NIR reflective layer can satisfy the requirements for miniaturization, and can suppress the dependence on the incident angle while maintaining high productivity. Further, for forming the dielectric multilayer film, for example, a vacuum film forming process such as a CVD method, a sputtering method or a vacuum vapor deposition method, a wet film forming process such as a spray method or a dip method can be used.

As the NIR reflective layer, one layer (a group of dielectric multilayer films) may give predetermined optical characteristics, or two layers may give predetermined optical characteristics. When the present filter has two or more NIR reflective layers, each reflective layer may have the same configuration or a different configuration. When this filter has two or more NIR reflective layers, it is usually composed of a plurality of NIR reflective layers having different reflection bands. When two NIR reflective layers are provided, one is a near-infrared reflective layer that shields light in the short wavelength band of the near-infrared region, and the other is both the long-wavelength band and the near-ultraviolet region in the near-infrared region. It may be used as a near-infrared / near-ultraviolet reflective layer that shields the light of.

Examples of the antireflection layer include a dielectric multilayer film, an intermediate refractive index medium, and a moth-eye structure in which the refractive index gradually changes. Of these, a dielectric multilayer film is preferable from the viewpoint of optical efficiency and productivity. The antireflection layer is obtained by alternately laminating dielectric films like the reflection layer.

Further, it is preferable that the dielectric multilayer film satisfies all of the following (vi-1) to (vi-7) in the spectral transmittance curve of the incident angle of 5 ° and the spectral transmittance curve of 30 °.
(Vi-1) The average reflectance of light having a wavelength of 430 nm or more and less than 490 nm is 30% or less.
(Vi-2) The average reflectance of light having a wavelength of 490 nm or more and less than 590 nm is 30% or less.
(Vi-3) The average reflectance of light having a wavelength of 590 nm or more and less than 650 nm is 30% or less.
(Vi-4) The average transmittance of light having a wavelength of 430 nm or more and less than 490 nm is 70% or more.
(Vi-5) The average transmittance of light having a wavelength of 490 nm or more and less than 590 nm is 80% or more.
(Vi-6) The average transmittance of light having a wavelength of 590 nm or more and less than 650 nm is 80% or more.
(Vi-7) The average transmittance of light having a wavelength of 700 nm or more and less than 1000 nm is 20% or less.

When the dielectric multilayer film satisfies the above (vi-1) to (vi-7), it is possible to suppress the intensity fluctuation in the spectral characteristics called ripple.

In (vi-1)
The average reflectance is preferably 28% or less, more preferably 25% or less.
In (vi-2)
The average reflectance is preferably 15% or less, more preferably 10% or less.
In (vi-3)
The average reflectance is preferably 15% or less, more preferably 10% or less.

In (vi-4)
The average transmittance is preferably 72% or more, more preferably 74% or more.
In (vi-5)
The average transmittance is preferably 85% or more, more preferably 87% or more.
In (vi-6)
The average transmittance is preferably 85% or more, more preferably 87% or more.

In (vi-7)
The average transmittance is preferably 18% or less, more preferably 15% or less.

[Image pickup device]
This filter can be used, for example, in an image pickup device such as a digital still camera.
Excellent color reproducibility when this filter is used in an image pickup device.

The image pickup device includes a solid-state image pickup element, an image pickup lens, and this filter. This filter can be used, for example, by being arranged between an image pickup lens and a solid-state image pickup element, or by being directly attached to a solid-state image pickup element, an image pickup lens, or the like of an image pickup device via an adhesive layer.

Next, the present invention will be described in more detail by way of examples.

[Dye compound]
<Dye compound 1-1>
"DA115" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 1-1.

<Dye compound 1-2>
The following dye compounds 1-2 were synthesized with reference to Japanese Patent No. 6504176.

<Dye compound 1-3>
The following dye compounds 1-3 were synthesized with reference to Japanese Patent No. 6504176.

<Dye compound 1-4>
"DAA108" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 1-4.

<Dye compound 1-5>
"FDB005" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 1-5.

<Dye compound 2-1>
"FDB005" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 2-1.

<Dye compound 2-2>
"DAA108" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 2-2.

<Dye compound 2-3>
"FDB006" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 2-3.

<Dye compound 2-4>
"FDG002" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 2-4.

<Dye compound 2-5>
"FDB19" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 2-5.

<Dye compound 2-6>
"DA115" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 2-6.

<Dye compound 3-1>
"IMM2" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 3-1.

<Dye compound 3-2>
"FDG003" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 3-2.

<Dye compound 3-3>
The following dye compound 3-3 was synthesized with reference to Japanese Patent Application Laid-Open No. 2001-183522.

<Dye compound 4-1>
"FDR003" manufactured by Yamada Chemical Co., Ltd. was designated as the dye compound 4-1.

<Dye compound 4-2>
The following dye compound 4-2 was synthesized with reference to Japanese Patent No. 6197940.

[Test Example 1]
<Test Example 1a-1>
Dye compound 1-1 and C-3G30G (manufactured by Mitsubishi Gas Chemical Company, polyimide varnish) diluted with cyclohexanone are mixed, and the dye compound 1-1 is sufficiently dissolved with the polyimide resin solution to form a resin solution (containing the dye compound). Amount: 4.5% by mass) was obtained.

The obtained resin solution was applied to D263 (alkaline glass) manufactured by Schott using a spin coat, and sufficiently heated to remove the organic solvent to prepare a coating film having a thickness of 1.0 μm.

The obtained coating film was measured for transmission spectroscopy in the incident direction of 0 ° and 5 ° with respect to the incident direction in the wavelength range of 350 nm to 1200 nm with an ultraviolet-visible near-infrared spectrophotometer "UH4150" manufactured by Hitachi High-Tech Science. ..

From the obtained transmittance and reflectance data, the internal transmittance at a wavelength of 350 nm to 1200 nm was calculated based on the following formula.
Internal transmittance = {T _{0 deg} / (100-R _{5 deg} )} x 100
T _{0 deg} means the measured transmittance of 0 °, and R 5 _deg means the reflectance of 5 °.

Table 4 shows the results of correction so that the internal transmittance at the absorption maximum wavelength is 10%.

<Test Examples 1a-2 to 1a-8>
The same operation as in Test Example 1a-1 was performed except that the type of the dye compound, the content of the dye compound, and the type of the resin were set as shown in Table 4. The results are shown in Table 4.

The meaning of each term is as follows.
C-3G30G: Mitsubishi Gas Chemicals, polyimide varnish F4520: JSR, cycloolefin resin B-OKP2: Osaka Gas Chemicals, polyester resin IR80a: The highest internal transmittance of 80% in the wavelength range of 395 nm or more and less than 450 nm. Long wavelength IR80b: Shortest wavelength with internal transmittance of 80% in the wavelength range of 395 nm or more and less than 450 nm IR10: Wavelength with internal transmittance of 10% in the wavelength range of 395 nm or more and less than 450 nm λ _Max : Absorption maximum wavelength

<Test Examples 1b-1 to 1b-11>
The same operation as in Test Example 1a-1 was performed except that the type of the dye compound, the content of the dye compound, the type of the resin, and the thickness of the coating film were set as shown in Table 5. The results are shown in Table 5.

The meaning of each term is as follows.
IR80a: The longest wavelength with an internal transmittance of 80% in the wavelength range of 450 nm or more and less than 540 nm IR80b: The shortest wavelength with an internal transmittance of 80% in the wavelength range of 450 nm or more and less than 540 nm IR10: Wavelength of 450 nm or more and less than 540 nm Wavelength with internal transmittance of 10% in the range

<Test Examples 1c-1 to 1c-5>
The same operation as in Test Example 1a-1 was performed except that the type of the dye compound, the content of the dye compound, the type of the resin, and the thickness of the coating film were set as shown in Table 6. The results are shown in Table 6.

The meaning of each term is as follows.
IR80a: The longest wavelength with an internal transmittance of 80% in the wavelength range of 540 nm or more and less than 600 nm IR80b: The shortest wavelength with an internal transmittance of 80% in the wavelength range of 540 nm or more and less than 600 nm IR10: Wavelength of 540 nm or more and less than 600 nm Wavelength with internal transmittance of 10% in the range

<Test Examples 1d-1 to 1d-2>
The same operation as in Test Example 1a-1 was performed except that the type of the dye compound, the content of the dye compound, the type of the resin, and the thickness of the coating film were set as shown in Table 7. The results are shown in Table 7.

The meaning of each term is as follows.
IR80a: The longest wavelength with an internal transmittance of 80% in the wavelength range of 600 nm or more and less than 720 nm IR80b: The shortest wavelength with an internal transmittance of 80% in the wavelength range of 600 nm or more and less than 720 nm IR10: Wavelength of 600 nm or more and less than 720 nm Wavelength with internal transmittance of 10% in the range

[Test Example 2]
<Test Example 2-1>
Dye compound 1-2 (2.55% by mass), Dye compound 2-5 (3.56% by mass), Dye compound 3-3 (3.34% by mass), Dye compound 4-2 (4.06% by mass) ), C-3G30G diluted with cyclohexanone (manufactured by Mitsubishi Gas Chemicals, polyimide varnish) was mixed, and the dye compound and the polyimide resin solution were sufficiently dissolved to obtain a resin solution.

The obtained resin solution was applied to D263 (alkaline glass) manufactured by Schott using a spin coat, and sufficiently heated to remove the organic solvent to prepare a coating film having a thickness of 2 μm.

The obtained coated film was measured for transmission spectroscopy in the incident direction at 0 ° with respect to the incident direction in the wavelength range of 350 nm to 1200 nm with an ultraviolet-visible near-infrared spectrophotometer "UH4150" manufactured by Hitachi High-Tech Science. The results are shown in Table 8.

<Test Examples 2-2-2-4>
The same operation as in Test Example 2-1 was carried out except that the types and contents of the dye compounds were as shown in Table 8. The results are shown in Table 8.

[Test Example 3]
A 48-layer dielectric multilayer film composed of SiO ₂ and TiO ₂ was formed on D263 (alkaline glass) manufactured by Schott by vapor deposition. The obtained dielectric multilayer film is measured for transmission spectroscopy in the incident direction of 5 ° and 30 ° with respect to the incident direction in the wavelength range of 350 nm to 1200 nm with the ultraviolet-visible near-infrared spectrophotometer "UH4150" manufactured by Hitachi High-Tech Science. did. The results are shown in Table 9.

From Test Example 3, it was found that the obtained dielectric multilayer film had a sufficiently high transmittance in the visible band and a low reflection transmittance in the visible band.

[Test Example 4]
<Test Example 4-1 (Example)>
Dye compound 1-2 (2% by mass), Dye compound 2-5 (2.8% by mass), Dye compound 3-3 (2.5% by mass), Dye compound 4-2 (4.5% by mass), C-3G30G (manufactured by Mitsubishi Gas Chemicals, polyimide varnish) diluted with cyclohexanone was mixed, and the dye compound and the polyimide resin solution were sufficiently dissolved to obtain a resin solution.

Further, the dielectric multilayer film obtained in Test Example 3 was formed by thin film deposition on D263 (alkaline glass, thickness 0.2 mm) manufactured by Schott.

A resin solution obtained by using a spin coat is applied to D263 (alkaline glass) on which a dielectric multilayer film is formed, and the coating film is sufficiently heated to remove the organic solvent to obtain a coating film having a thickness of 3 μm. Made. A seven-layer antireflection film composed of SiO ₂ and TiO ₂ was formed by thin film deposition on the obtained coating film.

The coated film with the antireflection film vapor-deposited is subjected to transmission spectroscopy in the incident direction of 0 ° and 30 ° with respect to the incident direction in the wavelength range of 350 nm to 1200 nm with the ultraviolet visible near infrared spectrophotometer "UH4150" manufactured by Hitachi High-Tech Science. It was measured. The results are shown in Table 10.

<Test Example 4-2 (Example)>
The same operation as in Test Example 4-1 was performed except that D263 (alkaline glass) was changed to borosilicate glass (manufactured by AGC) that cuts infrared rays. The results are shown in Table 11 and FIG.

<Test Example 4-3>
A 34-layer dielectric multilayer film composed of SiO ₂ and TiO ₂ through which light in the blue band, light in the green band, and light in the red band is transmitted to D263 (alkaline glass, thickness 0.2 mm) manufactured by shotto. A film was formed by vapor deposition.

The obtained film was measured for transmission spectroscopy at 0 ° and 30 ° with respect to the incident direction in the wavelength range of 350 nm to 1200 nm with an ultraviolet-visible near-infrared spectrophotometer "UH4150" manufactured by Hitachi High-Tech Science. The results are shown in Table 12.

From Test Example 4, it was found that the coating film (resin layer) of the example had sufficiently high transmittance in the blue band, transmittance in the green band, and transmittance in the red band.

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 invention. This application is based on a Japanese patent application filed on August 14, 2020 (Japanese Patent Application No. 2020-137088), the contents of which are incorporated herein by reference.

10 Optical filter 11 Base material 12 Dielectric multilayer film

Claims (11)

1. An optical filter comprising a base material and a dielectric multilayer film laminated as an outermost layer on at least one main surface side of the base material.
   The base material has a resin layer containing a resin and a dye A, and has a resin layer.
   The dye A has an absorption maximum wavelength in a wavelength range of 400 nm or more and less than 700 nm in the spectral transmittance curve of the coating film obtained by dissolving the dye A in the resin and applying the dye A on a glass substrate.
   An optical filter that satisfies all of the following (i-1) to (i-9).
   (I-1) In the spectral transmittance curve with an incident angle of 0 °,
   It has a maximum value of 1 _{(0 deg)} in the wavelength range of 430 nm or more and less than 490 nm.
   It has a maximum value of 2 _{(0 deg)} in the wavelength range of 490 nm or more and less than 590 nm.
   It has a maximum value of 3 _{(0 deg)} in the wavelength range of 590 nm or more and less than 650 nm.
   (I-2) In the spectral transmittance curve with an incident angle of 30 °,
   It has a maximum value of 1 _{(30 deg)} in the wavelength range of 430 nm or more and less than 490 nm.
   It has a maximum value of 2 _{(30 deg)} in the wavelength range of 490 nm or more and less than 590 nm.
   It has a maximum value of 3 _{(30 deg)} in the wavelength range of 590 nm or more and less than 650 nm.
   (I-3) In the spectral transmittance curve with an incident angle of 0 °, the wavelength range is a minimum value of 1 _{(0 deg)} or a transmittance of 1% or less in a wavelength range of 440 nm or more and less than 550 nm.
   It has a minimum value of 2 _{(0 deg)} or a wavelength range in which the transmittance is 1% or less in a wavelength range of 490 nm or more and less than 610 nm.
   (I-4) In the spectral transmittance curve with an incident angle of 30 °, the wavelength range is a minimum value of 1 _{(30 deg)} or a transmittance of 1% or less in a wavelength range of 440 nm or more and less than 550 nm.
   It has a minimum value of 2 _{(30 deg)} or a wavelength range in which the transmittance is 1% or less in a wavelength range of 490 nm or more and less than 610 nm.
   (I-5) All of the following equations are satisfied.
   Maxima 1 _(0deg) -Maximum 1 _(0deg) ≧ 30%
   Maxima 2 _(0deg) -Maximum 1 _(0deg) ≧ 30%
   Maxima 2 _(0deg) -Maximum 2 _(0deg) ≧ 30%
   Maxima 3 _(0deg) -Maximum 2 _(0deg) ≧ 27%
   (I-6) All of the following equations are satisfied.
   Maxima 1 _(30deg) -Maximum 1 _(30deg) ≧ 30%
   Maxima 2 _(30deg) -Maximum 1 _(30deg) ≧ 30%
   Maxima 2 _(30deg) -Maximum 2 _(30deg) ≧ 30%
   Maxima 3 _(30deg) -Maximum 2 _(30deg) ≧ 27%
   (I-7) In the spectral transmittance curve with an incident angle of 0 °,
   The average transmittance _{(0 deg)} in the wavelength range of 700 to 1000 nm is 5% or less.
   (I-8) In the spectral transmittance curve with an incident angle of 30 °,
   The average transmittance _{(30 deg)} in the wavelength range of 700 to 1000 nm is 5% or less.
   (I-9) All of the following equations are satisfied.
   0.85 ≤ maximum value 1 ₍₃₀ deg) / maximum value 1 _{(0 deg)} ≤ 1.12
   0.85 ≤ maximum value 2 ₍₃₀ deg) / maximum value 2 _{(0 deg)} ≤ 1.12
   0.85 ≤ maximum value 3 ₍₃₀ deg) / maximum value 3 _{(0 deg)} ≤ 1.12
2. The optical filter according to claim 1, further satisfying all of the following equations.
   | Wavelength λ1 _{(0 deg) -Wavelength λ1 (30} deg) | ≤10 nm
   | Wavelength λ2 _{(0 deg) -Wavelength λ2 (30} deg) | ≤10 nm
   | Wavelength λ3 _{(0 deg) -Wavelength λ3 (30} deg) | ≤10 nm
   | Wavelength λ4 _{(0 deg)} -Wavelength λ4 ₍₃₀ deg) | ≤10 nm
   <In the formula, wavelength λ1 _(0deg) , wavelength λ1 _(30deg) , wavelength λ2 _(0deg) , wavelength λ2 _(30deg) , wavelength λ3 _(0deg) , wavelength λ3 _(30deg) , wavelength λ4 _(0deg) , wavelength λ4 ₍ 30deg). ₎ Is a value obtained by the following formula.
   Wavelength λ1 _(0deg) = {wavelength at maximum value 1 _(0deg) + wavelength at minimum value 1 _(0deg) } ÷ 2
   Wavelength λ1 _(30deg) = {wavelength at maximum value 1 _(30deg) + wavelength at minimum value 1 _(30deg) } / 2
   Wavelength λ2 _(0deg) = {wavelength at maximum value 2 _(0deg) + wavelength at minimum value 1 _(0deg) } ÷ 2
   Wavelength λ2 _(30deg) = {wavelength at maximum value 2 _(30deg) + wavelength at minimum value 1 _(30deg) } ÷ 2
   Wavelength λ3 _(0deg) = {wavelength at maximum value 2 _(0deg) + wavelength at minimum value 2 _(0deg) } ÷ 2
   Wavelength λ3 _(30deg) = {wavelength at maximum value 2 _(30deg) + wavelength at minimum value 2 _(30deg) } ÷ 2
   Wavelength λ4 _(0deg) = {wavelength at maximum value 3 _(0deg) + wavelength at minimum value 2 _(0deg) } ÷ 2
   Wavelength λ4 _(30deg) = {wavelength at maximum value 3 _(30deg) + wavelength at minimum value 2 _(30deg) } ÷ 2>
3. The dye A contains dye 1, dye 2, dye 3 and dye 4.
   The optical filter according to claim 1 or 2, wherein the following (ii-1) to (ii-4) are all satisfied.
   (Ii-1) In the spectral transmittance curve of the coating film obtained by dissolving the dye 1 in the resin and coating it on a glass substrate, the dye 1 has an absorption maximum wavelength in a wavelength range of 395 nm or more and less than 450 nm. ..
   (Ii-2) In the spectral transmittance curve of the coating film obtained by dissolving the dye 2 in the resin and coating the glass substrate, the dye 2 has an absorption maximum wavelength in a wavelength range of 450 nm or more and less than 540 nm. ..
   (Ii-3) In the spectral transmittance curve of the coating film obtained by dissolving the dye 3 in the resin and coating the glass substrate, the dye 3 has an absorption maximum wavelength in a wavelength range of 540 nm or more and less than 600 nm. ..
   (Ii-4) In the spectral transmittance curve of the coating film obtained by dissolving the dye 4 in the resin and coating the glass substrate, the dye 4 has an absorption maximum wavelength in a wavelength range of 600 nm or more and less than 720 nm. ..
4. The optical filter according to claim 3, wherein the dye 1, the dye 2, the dye 3, the dye 4, and the resin layer having the resin satisfy all of the following (iii-1) to (iii-3).
   (Iii-1) It has a maximum value of 10 in the wavelength range of 430 nm or more and less than 490 nm, and has a maximum value of 10.
   It has a maximum value of 11 in the wavelength range of 490 nm or more and less than 590 nm, and has a maximum value of 11.
   It has a maximum value of 12 in the wavelength range of 590 nm or more and less than 650 nm.
   (Iii-2) The wavelength range is 400 nm or more and less than 440 nm, and the minimum value is 10 or the internal transmittance is 1% or less.
   It has a minimum value of 11 or a wavelength range in which the internal transmittance is 1% or less in a wavelength range of 440 nm or more and less than 540 nm.
   It has a minimum value of 12 or a wavelength range in which the internal transmittance is 1% or less in a wavelength range of 540 nm or more and less than 640 nm.
   It has a minimum value of 13 or a wavelength range in which the internal transmittance is 1% or less in a wavelength range of 640 nm or more and less than 700 nm.
   (Iii-3) The maximum value among the maximum value 10, the maximum value 11, and the maximum value 12 is 40% or more.
5. The optical filter according to claim 3 or 4, further satisfying all of the following (iv-1) to (iv-4).
   (Iv-1) In the spectral transmittance curve of the coating film coated by dissolving the dye 1 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
   IR80a _{(dye 1)} is the longest wavelength with an internal transmittance of 80% in the wavelength range of 395 nm or more and less than 450 nm.
   When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 1)} , the following equation is satisfied.
   IR80a _{(dye 1)} -IR10 ₍ dye 1) ≤25 nm
   (Iv-2) In the spectral transmittance curve of the coating film coated by dissolving the dye 2 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
   IR80a _{(dye 2)} is the longest wavelength in which the internal transmittance is 80% in the wavelength range of 450 nm or more and less than 540 nm.
   The shortest wavelength at which the internal transmittance is 80% is IR80b _{(dye 2)} .
   When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 2)} , the following equation is satisfied.
   IR80a _{(dye 2)} -IR10 ₍ dye 2) ≤35 nm
   IR80b _{(dye 2)} -IR10 ₍ dye 2) ≤55 nm
   (Iv-3) In the spectral transmittance curve of the coating film coated by dissolving the dye 3 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
   IR80a _{(dye 3)} is the longest wavelength in which the internal transmittance is 80% in the wavelength range of 540 nm or more and less than 600 nm.
   The shortest wavelength at which the internal transmittance is 80% is IR80b _{(dye 3)} .
   When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 3)} , the following equation is satisfied.
   IR80a _{(dye 3)} -IR10 ₍ dye 3) ≤35 nm
   IR80b _{(dye 3)} -IR10 ₍ dye 3) ≤55 nm
   (Iv-4) In the spectral transmittance curve of the coating film coated by dissolving the dye 4 in the resin on a glass substrate so that the internal transmittance at the absorption maximum wavelength is 10%.
   IR80b _{(dye 4)} is the shortest wavelength in which the internal transmittance is 80% in the wavelength range of 600 nm or more and less than 720 nm.
   When the wavelength at which the internal transmittance is 10% is IR10 _{(dye 4)} , the following equation is satisfied.
   IR80b _{(dye 4)} -IR10 ₍ dye 4) ≤80 nm
6. The optical filter according to any one of claims 3 to 5, wherein the dye 1 is a compound represented by the following formula (1).
   

   

   (In the formula (1), R ¹ represents a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent.
   ^R2 to R5 independently represent 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.
   Y represents a methylene group or oxygen atom substituted with R ⁶ and R ⁷ .
   R ⁶ and R ⁷ independently represent 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.
   X represents any of the following formulas (X1) to (X5). )
   

   

   (In formulas (X1) to (X4), R ⁸ and R ⁹ each independently represent a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent.
   R ¹⁰ to R ¹⁹ each independently represent a hydrogen atom or a monovalent hydrocarbon group having 1 to 12 carbon atoms which may have a substituent. )
7. The optical filter according to any one of claims 3 to 6, wherein the dye 3 is a compound represented by the following formula (3).
   

   

   (In the formula (3), R ¹⁰¹ and R ¹⁰² each independently have an alkyl group which may have a substituent, an alkenyl group which may have a substituent, and even if they have a substituent. Represents a good alkoxycarbonyl group, or a phenyl group which may have a substituent.
   n represents an integer of 0 to 3 independently. )
8. The optical filter according to any one of claims 3 to 7, wherein the dye 4 is a compound represented by the following formula (4).
   

   

   <In the formula (4), R ²¹ and R ²² each independently have a hydrogen atom, an alkyl group or an allyl group having 1 to 6 carbon atoms which may have a substituent, or a substituent. An aryl group or an alaryl group having 6 to 11 carbon atoms which may be used is shown.
   R ²³ and R ²⁵ each independently represent a hydrogen atom, a halogen atom, or an alkyl group or an alkoxy group having 1 to 6 carbon atoms.
   R ²⁴ and R ²⁶ independently represent a hydrogen atom, a halogen atom, a hydroxyl group, an alkyl or alkoxy group having 1 to 6 carbon atoms, an acyloxy group having 1 to 10 carbon atoms, and -NR ²⁷ R ²⁸ .
   R ²⁷ and R ²⁸ are independently each of a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, -C (= O) -R ²⁹ , -NHR ³⁰ , -SO ₂ -R ³⁰ , or the following formula ( The group represented by S) is shown.
   R ²⁹ may have a hydrogen atom, an alkyl group having 1 to 20 carbon atoms which may have a substituent, an aryl group having 6 to 11 carbon atoms, or a substituent, and an oxygen atom between carbon atoms. Indicates an alaryl group having 7 to 18 carbon atoms which may have.
   In R ³⁰ , one or more hydrogen atoms may be substituted with a halogen atom, a hydroxyl group, a carboxy group, a sulfo group, or a cyano group, and an unsaturated bond, an oxygen atom, a saturated or unsaturated group between carbon atoms. It shows a hydrocarbon group having 1 to 25 carbon atoms which may contain a ring structure.
   

   

   (In the formula (S), R ⁴¹ and R ⁴² each independently represent a hydrogen atom, a halogen atom, or an alkyl group or an alkoxy group having 1 to 10 carbon atoms.
   k represents 2 or 3. )
   R ²¹ and R ²² , R ²² and R ²⁵ , and R ²¹ and R ²³ are connected to each other to form a heterocycle A, a heterocycle B, and a heterocycle C having 5 or 6 members together with a nitrogen atom, respectively. May be.
   When the heterocyclic ring A is formed, R ²¹ and R ²² have a divalent group −Q— to which they are bonded, and the hydrogen atom is an alkyl group having 1 to 6 carbon atoms and an aryl group having 6 to 10 carbon atoms. Alternatively, an alkylene group or an alkyleneoxy group which may be substituted with an acyloxy group having 1 to 10 carbon atoms which may have a substituent is shown.
   R ²² and R ²⁵ when the heterocycle B is formed, and R ²¹ and R ²³ when the heterocycle C is formed are the divalent groups -X ¹ -Y ^1- and X to which they are bonded, respectively. As ² -Y2- (X ¹ and X ² on the side that binds to nitrogen), X ¹ and X ² are groups represented by the following formulas (1x) or ( ^2x ), respectively, and Y ¹ and Y ² are the following, respectively. It is a group represented by any one selected from the formulas (1y) to (5y).
   When X ¹ and X ² are groups represented by the following formulas (2x), Y ¹ and Y ² may be single bonds, respectively, and in that case, oxygen atoms may be provided between carbon atoms. ..
   

   

   (In the formula (1x), each of the four Zs independently represents 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 ³¹ to R ³⁶ independently represent 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 ³⁸ and R ³⁹ each independently represent a hydrogen atom or an alkyl group having 1 to 20 carbon atoms. )
   R ²⁷ , R ²⁸ , R ²⁹ , R ³¹ to R ³⁷ , R ²¹ to R ²³ when no heterocycle is formed, and R ²⁵ are 5-membered rings coupled to any other of these. Alternatively, a 6-membered ring may be formed. R ³¹ and R ³⁶ , and R ³¹ and R ³⁷ may be directly coupled. ＞
9. Any of claims 1 to 8, wherein the dielectric multilayer film satisfies all of the following (vi-1) to (vi-7) in a spectral transmittance curve having an incident angle of 5 ° and a spectral transmittance curve of 30 °. The optical filter according to item 1.
   (Vi-1) The average reflectance of light having a wavelength of 430 nm or more and less than 490 nm is 30% or less.
   (Vi-2) The average reflectance of light having a wavelength of 490 nm or more and less than 590 nm is 30% or less.
   (Vi-3) The average reflectance of light having a wavelength of 590 nm or more and less than 650 nm is 30% or less.
   (Vi-4) The average transmittance of light having a wavelength of 430 nm or more and less than 490 nm is 70% or more.
   (Vi-5) The average transmittance of light having a wavelength of 490 nm or more and less than 590 nm is 80% or more.
   (Vi-6) The average transmittance of light having a wavelength of 590 nm or more and less than 650 nm is 80% or more.
   (Vi-7) The average transmittance of light having a wavelength of 700 nm or more and less than 1000 nm is 20% or less.
10. The base material has a support and
    The resin layer is laminated on at least one main surface of the support.
    The optical filter according to any one of claims 1 to 9, wherein the support includes transparent glass or absorbent glass.
11. The optical filter according to any one of claims 1 to 10, wherein the resin is a polyimide resin.

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