WO2015137084A1

WO2015137084A1 - Ir cut filter

Info

Publication number: WO2015137084A1
Application number: PCT/JP2015/054725
Authority: WO
Inventors: 孔二中村; 英隆地大; 宗矩川路
Original assignee: コニカミノルタ株式会社
Priority date: 2014-03-11
Filing date: 2015-02-20
Publication date: 2015-09-17
Also published as: JPWO2015137084A1; JP6458797B2

Abstract

This IR cut filter comprises dielectric multilayer films on either side of a substrate and exhibits a mean transmittance of at least 95% over the 425-620 nm wavelength range at an angle of incidence of 0°, a mean transmittance of at least 94% over the 425-620 nm wavelength range at an angle of incidence of 30°, a mean transmittance of at least 91% over the 600-620 nm wavelength range at an angle of incidence of 0°, a mean transmittance of at most 0.5% and a maximum transmittance of at most 1.8% over the 700-1,100 nm wavelength range, and a mean transmittance of at most 8% and a maximum transmittance of at most 12.5% over the 1,100-1,200 nm wavelength range. Over the 580-700 nm wavelength range, this IR cut filter satisfies the relations Σ[T = 50% to 90%] |λT(0°)−λT(30°)| < 400 and Σ[T = 5% to 50%] |λT(0°)−λT(30°)| < 850 (where Σ[T = a% to b%] |λT(0°)−λT(30°)| represents the wavelength difference |λT(0°)−λT(30°)| summed as the transmittance T is increased from a% to b% in increments of 1% and λT(θ) represents the wavelength (in nm) at which the transmittance at an angle of incidence of θ° is T%).

Description

Infrared cut filter

The present invention relates to an infrared cut filter, for example, an infrared cut filter used for a camera unit.

In digital devices with an image input function such as a mobile phone with a camera and a smartphone (high-performance mobile phone), a silicon semiconductor device (for example, a CCD (Charge) is used as an image sensor that converts an optical image formed by an imaging lens into an electrical signal. 2. Description of the Related Art Conventionally, a solid-state imaging device such as a coupled device (Image sensor) and a CMOS (Complementary Metal-Oxide Semiconductor) image sensor) has been used. Since this silicon semiconductor device has sensitivity up to the near-infrared region, near-infrared light is captured as an image in addition to visible light when light enters. As a result, problems such as generation of pseudo colors occur in the obtained video.

Therefore, in the conventional digital device with an image input function, this problem is solved by inserting an infrared cut filter between the imaging lens and the imaging element. Various types of infrared cut filters have been proposed. For example, Patent Documents 1 to 3 propose infrared cut filters for cameras that have little incident angle dependency.

WO2013 / 042738 A1 JP 2013-178338 A US2013 / 0021515 A1

In a camera unit equipped with an imaging lens, an imaging element, etc., the incident angle of the light beam to the infrared cut filter increases with the reduction in the height of the camera and the increase in the size of the imaging element. In the case of a general infrared cut filter in which a dielectric multilayer film is formed on both surfaces of a glass substrate, since the shift amount of the cutoff wavelength is large at an incident angle of 0 degrees and an incident angle of 30 degrees, the center portion of the screen and the peripheral portion The color shading phenomenon in which colors differ between and will occur. Although it is possible to suppress the occurrence of the color shading phenomenon by using the absorbing glass, if the absorbing glass is made thin, the amount of absorption cannot be secured or the drop strength is reduced.

In the case of the infrared cut filter described in Patent Document 1, a transparent substrate having a transmittance of 90% to 50% has a large sum of wavelength differences between an incident angle of 0 degrees and 30 degrees, so that there is little color shading. I can't say that. In the case of the infrared cut filter described in Patent Document 2, it cannot be said that the ghost is small because the average transmittance at a wavelength of 600 to 620 is small, and the maximum transmittance at a wavelength of 700 to 1100 nm is large. It cannot be said that there is little red fogging with red on the color. In the case of the infrared cut filter described in Patent Document 3, the average transmittance at a wavelength of 1100 to 1200 nm is not disclosed, and it is difficult to reproduce the characteristics from the film configuration, but it can be said that the red fog is small. Absent. Moreover, although the multilayer film characteristic of each substrate surface is unknown, it is not a film structure with good productivity.

The present invention has been made in view of such circumstances, and an object thereof is to provide an infrared cut filter with little ghost, color shading, and red fog.

In order to achieve the above object, the infrared cut filter of the present invention is an infrared cut filter having a dielectric multilayer film on both sides of a substrate,
The average transmittance at an incident angle of 0 degree at a wavelength of 425 to 620 nm is 95% or more,
The average transmittance at an incident angle of 30 degrees at a wavelength of 425 to 620 nm is 94% or more,
The average transmittance at an incident angle of 0 degree at a wavelength of 600 to 620 nm is 91% or more,
The following conditional expressions (1) and (2) are satisfied at a wavelength of 580 to 700 nm,
The average transmittance at a wavelength of 700 to 1100 nm is 0.5% or less and the maximum transmittance is 1.8% or less,
The average transmittance at a wavelength of 1100 to 1200 nm is 8% or less and the maximum transmittance is 12.5% or less.
Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degree) | <400 (1)
Σ [T = 5 to 50%] | λT (0 degree) −λT (30 degree) | <850 (2)
However,
Σ [T = a˜b%] | λT (0 degree) −λT (30 degree) |: Wavelength difference for every 1% from the transmittance T of a% to b% | λT (0 degree) −λT (30 Degree) |
λT (θ): wavelength (nm) at an incident angle θ degree and transmittance T%,
It is.

The camera unit of the present invention includes the infrared cut filter.

According to the present invention, since the dielectric multilayer film characterized by spectral characteristics is provided on both sides of the substrate, an infrared cut filter with less ghost, color shading and red fog, and a camera unit having the same Can be realized. Then, by using the camera unit according to the present invention for a digital device such as a digital camera or a smartphone, a high-performance image input function can be realized at a low cost.

Sectional drawing which shows typically one Embodiment of an infrared cut filter. The figure for demonstrating the relationship between the spectral characteristic of an infrared cut filter, a ghost, a color shading, and a red fog. The figure for demonstrating the relationship between color shading and the sum of the amount of wavelength shifts. The block diagram which shows the schematic structural example of the digital apparatus with an image input function. The graph which shows the spectral transmittance of the whole filter of the comparative example 1. The graph which shows the spectral transmittance of each filter surface of the comparative example 1. FIG. The graph which shows the spectral transmittance of the whole filter of the comparative example 2. The graph which shows the spectral transmittance of each filter surface of the comparative example 2. FIG. The graph which shows the spectral transmittance of the whole filter of the comparative example 3. FIG. 10 is a graph showing the spectral transmittance of each filter surface in Comparative Example 3. 3 is a graph showing the spectral transmittance of the entire filter of Example 1. 3 is a graph showing the spectral transmittance of each filter surface of Example 1. 6 is a graph showing the spectral transmittance of the entire filter of Example 2. 6 is a graph showing the spectral transmittance of each filter surface of Example 2. 10 is a graph showing the spectral transmittance of the entire filter of Example 3. 6 is a graph showing the spectral transmittance of each filter surface of Example 3. 6 is a graph showing the spectral transmittance of the entire filter of Example 4. 6 is a graph showing the spectral transmittance of each filter surface of Example 4.

Hereinafter, an infrared cut filter, a camera unit and the like embodying the present invention will be described with reference to the drawings. FIG. 1 schematically shows a cross-sectional structure of an embodiment of an infrared cut filter FR in which dielectric multilayer films MA and MB are coated on both surfaces of a substrate SU (for example, a glass substrate). This infrared cut filter FR reduces ghost, color shading, and red fog favorably by imparting characteristic spectral characteristics to the dielectric multilayer films MA and MB on both surfaces of the substrate SU. The inventor produced infrared cut filters having various characteristics, incorporated them into a camera unit, performed image evaluation, and analyzed the evaluation results of filter characteristics, ghost, color shading, red fog, and the like. As a result, it has been found that there is a relationship described below between ghost, color shading, red fogging, and spectral characteristics of the infrared cut filter FR. An example is shown in FIG. 2 (θ: incident angle).

The ghost correlates with the reflectance in the visible region (wavelength 425 to 650 nm), and the generation of the ghost is suppressed when the reflectance is smaller. In other words, since the dielectric multilayer film hardly absorbs light in the visible region, ghost is suppressed when the transmittance is high. The characteristics related to the ghost are, specifically, an average transmittance at an incident angle of 0 degrees at a wavelength of 425 to 620 nm, an average transmittance at an incident angle of 30 degrees at a wavelength of 425 to 620 nm, and an incident at a wavelength of 600 to 620 nm. Average transmittance at an angle of 0 degrees. From the relationship between these numerical values and the image evaluation result of the live-action test, it is possible to calculate a threshold that can satisfactorily reduce ghosts.

Color shading is related to the transmittance difference between the incident angle of 0 degrees and 30 degrees with respect to the infrared cut filter, and the occurrence of color shading is suppressed when the transmittance difference is reduced. Specifically, the characteristics related to color shading are the sum of the wavelength shift amounts between 0 degree and 30 degrees of incident angles between 90% transmittance and 50% transmittance, and 50% transmittance to 5 transmittance. % Is the sum of the wavelength shift amounts between 0 degree and 30 degrees of incident angle. From the relationship between these numerical values and the image evaluation result of the live-action test, a threshold capable of satisfactorily reducing color shading can be calculated.

The red fog has a correlation with the transmittance at a wavelength of 700 to 1200 nm, and the smaller the transmittance, the more the occurrence of red fog is suppressed. Specifically, the characteristics related to the red fog are the average transmittance and the maximum transmittance at a wavelength of 700 to 1100 nm, and the average transmittance and the maximum transmittance at a wavelength of 1100 to 1200 nm. From the relationship between these numerical values and the image evaluation result of the live-action test, a threshold capable of satisfactorily reducing the red fog can be calculated.

The infrared cut filter FR according to the present invention based on the above viewpoint is an infrared cut filter having dielectric multilayer films MA and MB on both surfaces of a substrate SU,
The average transmittance at an incident angle of 0 degree at a wavelength of 425 to 620 nm is 95% or more,
The average transmittance at an incident angle of 30 degrees at a wavelength of 425 to 620 nm is 94% or more,
The average transmittance at an incident angle of 0 degree at a wavelength of 600 to 620 nm is 91% or more,
The following conditional expressions (1) and (2) are satisfied at a wavelength of 580 to 700 nm,
The average transmittance at a wavelength of 700 to 1100 nm is 0.5% or less and the maximum transmittance is 1.8% or less,
The average transmittance at a wavelength of 1100 to 1200 nm is 8% or less and the maximum transmittance is 12.5% or less.
Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degree) | <400 (1)
Σ [T = 5 to 50%] | λT (0 degree) −λT (30 degree) | <850 (2)
However,
Σ [T = a˜b%] | λT (0 degree) −λT (30 degree) |: Wavelength difference for every 1% from the transmittance T of a% to b% | λT (0 degree) −λT (30 Degree) |
λT (θ): wavelength (nm) at an incident angle θ degree and transmittance T%,
It is.

3 shows the relationship between color shading and the sum of wavelength shift amounts: Σ [T = a to b%] | λT (0 degree) −λT (30 degree) |. The shaded portion in FIG. 3A indicates the condition range defined by the conditional expression (1), and the shaded portion in FIG. 3B indicates the condition range defined by the conditional expression (2). Show. Conditional expressions (1) and (2) both define a condition range for favorably correcting color shading. Since conditional expression (1) defines a high transmittance range, effective color shading correction can be performed by setting the upper limit to satisfy conditional expression (1). On the other hand, since conditional expression (2) defines a low transmittance range, which is a weak range of sensor sensitivity, setting the upper limit to satisfy conditional expression (2) is effective for dealing with a small amount of light. Color shading correction is possible. Therefore, in order to suppress the occurrence of color shading, it is effective to satisfy both conditional expressions (1) and (2). That is, to satisfy the conditional expressions (1) and (2), the sum of the wavelength shift amounts of the incident angles of 0 degrees and 30 degrees between the transmittance 90% and the transmittance 50% and the transmittance 50% What is necessary is just to make both the sum of the wavelength shift amount of the incident angles 0 degree and 30 degree | times between the transmittance | permeability 5% small.

When reducing color shading with a small number of layers in order to improve productivity, the sum of the wavelength shift amounts between 0 degree and 30 degrees of incident angles between 90% transmittance and 50% transmittance: Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degree) | is emphasized, and if it is reduced, good results can be obtained. Sum of wavelength shifts: Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degrees) | When the optimum method for reducing it is considered, the wavelength shift is 580 to 700 nm. Of the two filter surfaces formed of the dielectric multilayer films MA and MB on both surfaces of the substrate SU, the surface with the shorter wavelength λ50% (0 degree) when the incident angle is 0 degree and the transmittance is 50% is defined as the A face. If the surface is the B surface, the wavelength shift is reduced by reducing the sum of wavelength shifts: Σ [T = 50 to 90%] | λT (0 degrees) −λT (30 degrees) | It is preferable that the B surface has a high transmittance so as not to affect the characteristics of the infrared cut filter FR at 580 to 700 nm. Further, the sum of the wavelength shift amounts of the incident angle between 0 degree and 30 degrees between the transmittance of 50% and the transmittance of 5%: Σ [T = 5-50%] | λT (0 degree) −λT (30 degrees If emphasizing |) and reducing it with the characteristics of the B surface, good results can be obtained in reducing color shading.

According to the above characteristic configuration, the dielectric multilayer films MA and MB having spectral characteristics are provided on both sides of the substrate SU, so that an infrared cut filter FR with less ghost, color shading and red fog is realized. can do. By using a camera unit including the infrared cut filter FR in a digital device such as a digital camera or a smartphone, a high-performance image input function can be realized at a low cost. The conditions for more effectively achieving ghost, color shading and red fog reduction will be described below.

It is preferable that the following conditional expression (3) is satisfied at a wavelength of 580 to 700 nm.
−15 ≦ λA 50% (0 degree) −λB 50% (30 degree) ≦ 10 (3)
However,
λA 50% (0 degree): wavelength (nm) when the incident angle is 0 degree on the A plane and the transmittance is 50%,
λB50% (30 degrees): wavelength (nm) at an incident angle of 30 degrees and a transmittance of 50% on the B surface,
It is.

As described above, it is important to reduce the wavelength shift amount with a transmittance of 90 to 50% on the A surface, while reducing the wavelength shift amount with a transmittance of 50 to 5% on the B surface. Wavelength difference between the wavelength λA50% (0 degree) when the incident angle is 0 degree and the transmittance is 50%, and the wavelength difference λB50% (30 degree) when the incident angle is 30 degrees and the transmittance is 50% on the B surface: λA50 % (0 degree) -λB50% (30 degrees). If this wavelength difference is too large (that is, if the overlap between the A side and the B side is large), the wavelength shift of 90% to 50% transmittance becomes large due to the influence of the B side characteristics, and the color shading deteriorates. To do. On the other hand, if the wavelength difference is too small (that is, the A and B surfaces do not overlap very much), the transmittance of 700 nm or more in wavelength increases due to the skirt of the cutoff region of the B surface, and the red fog is deteriorated. .

By satisfying conditional expression (3), the wavelength shift effective for color shading can be suppressed by the A-side dielectric multilayer film MA, and the infrared cut can be appropriately performed by the B-side dielectric multilayer film MB. Color shading increases when the upper limit of conditional expression (3) is exceeded, and red fog increases when the lower limit of conditional expression (3) is exceeded. Since the oblique characteristics are determined by the A-side dielectric multilayer film MA having a small angle dependency, and the infrared cut is performed by the B-side dielectric multilayer film MB, if below the lower limit of the conditional expression (3), Since λB50% (30 degrees) is farther away from λA50% (0 degrees), it becomes difficult to perform infrared cut around 700 nm with the spectral characteristics (0 degrees) of the dielectric multilayer film MB.

A design that suppresses ghost, color shading, and red fogging is possible by increasing the number of layers of each of the dielectric multilayer films MA and MB. However, as the number of layers increases, the surface roughness of the material and the material are slightly increased. Absorption causes light scattering and light absorption, and productivity also deteriorates. Therefore, in the infrared cut filter FR having the above-described configuration, the number of layers of the dielectric multilayer films MA and MB is preferably 200 or less on one side, and more preferably 100 or less on one side.

Regarding the characteristics related to the ghost, the average transmittance at an incident angle of 0 degrees at wavelengths of 425 to 620 nm is 99% or more, the average transmittance at an incident angle of 30 degrees at wavelengths of 425 to 620 nm is 97% or more, The average transmittance at an incident angle of 0 degree at 600 to 620 nm is preferably 98.5% or more. This condition stipulates a more preferable condition range based on the above viewpoints, etc., among the aforementioned ghost-related condition ranges. Therefore, preferably, the ghost reduction effect can be further increased by satisfying this condition.

The infrared cut filter FR preferably satisfies the following conditional expression (1a) at a wavelength of 580 to 700 nm.
Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degree) | <215 (1a)
The conditional expression (1a) defines a more preferable condition range based on the above viewpoints, etc., among the condition ranges defined by the conditional expression (1). Therefore, the color shading reduction effect can be further increased preferably by satisfying conditional expression (1a).

Regarding the characteristics related to red fog, the average transmittance at a wavelength of 700 to 1100 nm is 0.15% or less and the maximum transmittance is 1% or less, and the average transmittance at a wavelength of 1100 to 1200 nm is 4% or less and the maximum transmittance is 9%. % Or less, the average transmittance at a wavelength of 700 to 1100 nm is 0.1% or less and the maximum transmittance is 0.7% or less, and the average transmittance at a wavelength of 1100 to 1200 nm is 1% or less and the maximum transmittance is More preferably, the rate is 1.5% or less. These conditions define a more preferable condition range based on the above viewpoints, etc., among the above-described condition ranges related to red fog. Therefore, preferably, by satisfying this condition, the red fog reduction effect can be further increased.

In an imaging optical device (for example, a camera unit) mounted on a digital device (for example, a smartphone) with an image input function, use of the infrared cut filter FR according to the present invention is suitable. An imaging optical device is an optical device that is a main component of a camera used for still image shooting and moving image shooting of a subject, and is formed by, for example, an imaging lens that forms an optical image of an object (that is, a subject) and the imaging lens. An image sensor (for example, a solid-state image sensor such as a CCD image sensor or a CMOS image sensor) that converts the optical image that has been converted into an electrical signal, and an infrared cut filter disposed between the image sensor and the image sensor FR is provided to optically capture a subject image and output it as an electrical signal.

Examples of digital devices with an image input function include cameras such as digital cameras, video cameras, surveillance cameras, in-vehicle cameras, and videophone cameras. Built-in or external to personal computers, portable digital devices (for example, small information device terminals such as mobile phones, smartphones, tablet terminals, and mobile computers), peripheral devices (scanners, printers, etc.), and other digital devices. The one with a camera function is included. As can be seen from these examples, it is possible not only to configure a camera by using an imaging optical device, but also to add a camera function by mounting the imaging optical device on various devices. For example, a digital device with an image input function such as a smartphone can be configured.

FIG. 4 is a schematic cross-sectional view showing a schematic configuration example of a digital device DU as an example of a digital device with an image input function. The imaging optical device LU mounted on the digital device DU shown in FIG. 4 includes an imaging lens LN (AX: optical axis) that forms an optical image (image plane) IM of the object in order from the object (that is, subject) side, An infrared cut filter FR and an imaging element SR that converts an optical image IM formed on a light receiving surface (imaging surface) SS, which is a photoelectric conversion unit, by an imaging lens LN into an electrical signal are provided. When a digital device DU with an image input function is constituted by this imaging optical device LU, the imaging optical device LU is usually arranged inside the body, but when necessary to realize the camera function, a form as necessary is adopted. Is possible. For example, the unitized imaging optical device LU can be configured to be detachable or rotatable with respect to the main body of the digital device DU.

The digital device DU includes a signal processing unit 1, a control unit 2, a memory 3, an operation unit 4, a display unit 5 and the like in addition to the imaging optical device LU. The signal generated by the image sensor SR is subjected to predetermined digital image processing, image compression processing, and the like in the signal processing unit 1 as necessary, and recorded as a digital video signal in the memory 3 (semiconductor memory, optical disc, etc.) In some cases, it is transmitted to other devices via a cable or converted into an infrared signal or the like (for example, a communication function of a mobile phone). The control unit 2 is composed of a microcomputer, and controls functions such as a shooting function (still image shooting function, moving image shooting function, etc.), an image reproduction function, etc .; a lens moving mechanism for focusing, etc. For example, the control unit 2 controls the imaging optical device LU so as to perform at least one of still image shooting and moving image shooting of a subject. The display unit 5 includes a display such as a liquid crystal monitor, and performs image display using an image signal converted by the image sensor SR or image information recorded in the memory 3. The operation unit 4 is a part including operation members such as an operation button (for example, a release button) and an operation dial (for example, a shooting mode dial), and transmits information input by the operator to the control unit 2.

The infrared cut filter FR has optical characteristics in which the dielectric multilayer films MA and MB on both surfaces of the substrate SU both transmit visible light and reflect infrared light. For example, when producing an infrared cut filter that transmits light having a wavelength of 450 to 600 nm and reflects light having a wavelength of 700 nm or more, TiO ₂ and SiO ₂ constituting the dielectric multilayer films MA and MB are made of optical films. Film thicknesses corresponding to a quarter wavelength in the infrared region (for example, wavelength 900 nm) are alternately laminated. Then, in order to efficiently transmit light having a wavelength of 450 nm to 600 nm, the thickness of each layer is gradually shifted from the quarter wavelength to set the effect of interference. Examples of the film formation method of the infrared cut filter FR include vacuum deposition, ion assist film formation, ion plating film formation, sputter film formation (reactive sputter film formation, etc.), ion beam sputter film formation, and the like. The dielectric multilayer films MA and MB on both sides of the substrate SU are preferably formed by these film forming methods.

The substrate SU is preferably made of glass. The plastic substrate is not suitable for forming a dielectric multilayer film. Accordingly, a glass substrate is preferable to a plastic substrate as a reliable transparent substrate that has a certain degree of strength as the infrared cut filter FR and does not peel off.

The dielectric multilayer films MA and MB on both surfaces of the substrate SU are preferably made of at least two vapor deposition materials, and at least one of them is made of SiO ₂ or a mixture containing SiO ₂ . The dielectric multilayer films MA and MB on both surfaces of the substrate SU are both made of at least two vapor deposition materials, and at least one of them is made of TiO ₂ , Nb ₂ O ₅ , Ta ₂ O ₅ , ZrO ₂ or any one of them. It is preferable to consist of a mixture containing. A low-refractive index material such as SiO ₂ and a high-refractive index material such as TiO ₂ are preferable materials for imparting compressive stress, are easy to manufacture, and are preferable materials for the refractive index required for performance. .

Hereinafter, the configuration and the like of the infrared cut filter according to the present invention will be described more specifically with reference to the construction data of Comparative Examples 1 to 3 and Examples 1 to 4. The construction data indicates the film forming material and film thickness (nm) of each layer of the dielectric multilayer films MA and MB, and the refractive index n (wavelength 540 nm) of the substrate SU and film forming material. In Comparative Examples 1 to 3 and Examples 1 and 2, the dielectric multilayer films MA and MB are both alternating layers of a high refractive index layer made of Nb ₂ O ₅ and a low refractive index layer made of SiO ₂ ( In Examples 3 and 4, the dielectric multilayer films MA and MB are alternately composed of a high refractive index layer made of TiO ₂ and a low refractive index layer made of SiO _2. It is composed of layers (TiO2 / SiO2).

Table 1 shows the characteristic values and values corresponding to the conditional expressions of Comparative Examples 1 to 3 and Examples 1 to 4, and Table 2 shows the evaluation results obtained by using the following image evaluation method. Also, the graphs of FIGS. 5 to 18 show the spectral characteristics of Comparative Examples 1 to 3 and Examples 1 to 4. 5, FIG. 7, FIG. 15 and FIG. 17 show the spectral transmittance (incident angle θ = 0 °, 30 °) of the entire filter, and FIG. 6, FIG. The spectral transmittance (incident angle θ = 0 °, 30 °) of each filter surface (A surface, B surface) is shown.

[Image Evaluation Method] As shown in FIG. 4, an infrared cut filter FR is provided between the imaging lens LN (5 positive / negative / positive / negative elements) and the imaging element SR so that the A-side faces the imaging element SR. Placed and took pictures to evaluate the images. In the ghost evaluation (wavelength: 425 to 620 nm), the light source was arranged at a short side, a long side, and a diagonal at a pitch of 5 degrees with respect to the optical axis AX, and the appearance of the ghost was evaluated from the captured image. . In color shading evaluation (wavelength: 580 to 700 nm), a white light source was photographed as a light source, and the difference in color between the peripheral part and the central part was evaluated. In the red fog evaluation (wavelength: 700 to 1200 nm), a black object illuminated with a light source was photographed, and the difference in color between the photographed image and the object was evaluated. As the light source, DAYLIGHT (north window light), Cool White (cold white fluorescent light), HORIZON (sunset light), INCA (showcase light) were used.

In Table 1,
* 1: Average transmittance (%) at an incident angle of 0 degree at a wavelength of 425 to 620 nm.
* 2: Average transmittance (%) at an incident angle of 30 degrees at a wavelength of 425 to 620 nm,
* 3: Average transmittance (%) at an incident angle of 0 degree at a wavelength of 600 to 620 nm,
* 4: Average transmittance (%) at a wavelength of 700 to 1100 nm
* 5: Maximum transmittance (%) at a wavelength of 700 to 1100 nm
* 6: Average transmittance (%) at a wavelength of 1100 to 1200 nm
* 7: Maximum transmittance (%) at a wavelength of 1100 to 1200 nm.
λA 50% (0 degree): wavelength (nm) when the incident angle is 0 degree on the A plane and the transmittance is 50%,
λB50% (0 degree): wavelength (nm) when the incident angle is 0 degree on the B surface and the transmittance is 50%,
λB50% (30 degrees): wavelength (nm) at an incident angle of 30 degrees and a transmittance of 50% on the B surface,
These numerical values are shown together with the corresponding values of the conditional expressions (1) to (3).

In the evaluation results shown in Table 2,
D: unacceptable level
C: acceptable level with some problems,
B: acceptable level with no problem,
A: Acceptable level without any problem,
It was.

Comparative Example 1
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.39

Layer Material Film thickness (nm)
1 SiO2 188.38
2 Nb2O5 15.15
3 SiO2 32.36
4 Nb2O5 131.87
5 SiO2 32.99
6 Nb2O5 17.68
7 SiO2 398.71
8 Nb2O5 22.86
9 SiO2 34.94
10 Nb2O5 36.95
11 SiO2 185.92
12 Nb2O5 86.08
13 SiO2 19.58
14 Nb2O5 24.40
15 SiO2 44.06
16 Nb2O5 127.03
17 SiO2 26.41
18 Nb2O5 133.05
19 SiO2 27.31
20 Nb2O5 132.96
21 SiO2 29.16
22 Nb2O5 130.45
23 SiO2 31.00
24 Nb2O5 128.35
25 SiO2 31.06
26 Nb2O5 128.73
27 SiO2 33.58
28 Nb2O5 129.50
29 SiO2 36.22
30 Nb2O5 124.47
31 SiO2 53.14
32 Nb2O5 24.69
33 SiO2 13.91
34 Nb2O5 79.38
35 SiO2 200.47
36 Nb2O5 16.43
37 SiO2 200.03
38 Nb2O5 95.12
39 SiO2 131.85
40 Nb2O5 90.18
41 SiO2 144.59
42 Nb2O5 95.05
43 SiO2 161.79
44 Nb2O5 84.43
45 SiO2 37.89
46 Nb2O5 15.15
47 SiO2 58.99
48 Nb2O5 99.29
49 SiO2 169.89
50 Nb2O5 33.59
51 SiO2 29.51
52 Nb2O5 25.57
53 SiO2 170.14
54 Nb2O5 16.41
55 SiO2 22.54
56 Nb2O5 65.88
57 SiO2 18.69
58 Nb2O5 28.11
59 SiO2 203.62
60 Nb2O5 107.66
61 SiO2 206.28
62 Nb2O5 26.38
63 SiO2 27.17
64 Nb2O5 131.61
65 SiO2 173.95
66 Nb2O5 99.66
67 SiO2 157.76
68 Nb2O5 97.97
69 SiO2 83.39

Comparative Example 1
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.39

Layer Material Film thickness (nm)
1 Nb2O5 14.63
2 SiO2 47.88
3 Nb2O5 23.01
4 SiO2 191.84
5 Nb2O5 115.50
6 SiO2 25.77
7 Nb2O5 117.17
8 SiO2 52.53
9 Nb2O5 14.63
10 SiO2 35.23
11 Nb2O5 90.70
12 SiO2 190.20
13 Nb2O5 15.61
14 SiO2 221.29
15 Nb2O5 14.63
16 SiO2 217.11
17 Nb2O5 16.34
18 SiO2 187.01
19 Nb2O5 86.72
20 SiO2 25.86
21 Nb2O5 16.74
22 SiO2 49.39
23 Nb2O5 102.56
24 SiO2 18.22
25 Nb2O5 16.13
26 SiO2 28.51
27 Nb2O5 106.36
28 SiO2 19.32
29 Nb2O5 17.53
30 SiO2 23.21
31 Nb2O5 119.66
32 SiO2 21.56
33 Nb2O5 132.02
34 SiO2 19.79
35 Nb2O5 123.94
36 SiO2 15.24
37 Nb2O5 22.64
38 SiO2 14.63
39 Nb2O5 120.11
40 SiO2 18.69
41 Nb2O5 120.08
42 SiO2 24.50
43 Nb2O5 18.25
44 SiO2 18.36
45 Nb2O5 115.81
46 SiO2 22.13
47 Nb2O5 118.79
48 SiO2 42.60
49 Nb2O5 20.05
50 SiO2 22.85
51 Nb2O5 86.07
52 SiO2 156.82
53 Nb2O5 85.07
54 SiO2 157.16
55 Nb2O5 105.44
56 SiO2 178.10
57 Nb2O5 109.09
58 SiO2 176.07
59 Nb2O5 106.98
60 SiO2 174.50
61 Nb2O5 99.23
62 SiO2 164.22
63 Nb2O5 95.44
64 SiO2 167.02
65 Nb2O5 101.09
66 SiO2 85.49

Comparative Example 2
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 14.28
2 SiO2 35.73
3 Nb2O5 114.45
4 SiO2 196.82
5 Nb2O5 15.55
6 SiO2 203.33
7 Nb2O5 35.97
8 SiO2 28.56
9 Nb2O5 16.23
10 SiO2 134.47
11 Nb2O5 111.08
12 SiO2 33.69
13 Nb2O5 125.54
14 SiO2 29.75
15 Nb2O5 129.86
16 SiO2 29.14
17 Nb2O5 128.16
18 SiO2 29.69
19 Nb2O5 127.96
20 SiO2 29.89
21 Nb2O5 127.01
22 SiO2 30.13
23 Nb2O5 127.97
24 SiO2 30.59
25 Nb2O5 127.78
26 SiO2 30.36
27 Nb2O5 128.81
28 SiO2 29.79
29 Nb2O5 128.57
30 SiO2 28.59
31 Nb2O5 129.83
32 SiO2 27.90
33 Nb2O5 129.82
34 SiO2 27.10
35 Nb2O5 130.60
36 SiO2 26.84
37 Nb2O5 128.22
38 SiO2 27.16
39 Nb2O5 115.70
40 SiO2 48.45
41 Nb2O5 14.41
42 SiO2 32.98
43 Nb2O5 91.74
44 SiO2 41.00
45 Nb2O5 15.00
46 SiO2 38.68
47 Nb2O5 93.99
48 SiO2 27.72
49 Nb2O5 17.30
50 SiO2 34.30
51 Nb2O5 115.57
52 SiO2 24.24
53 Nb2O5 115.71
54 SiO2 28.56
55 Nb2O5 16.89
56 SiO2 28.56
57 Nb2O5 114.81
58 SiO2 28.56
59 Nb2O5 115.01
60 SiO2 55.50
61 Nb2O5 14.95
62 SiO2 28.56
63 Nb2O5 81.55
64 SiO2 145.32
65 Nb2O5 89.25
66 SiO2 191.09
67 Nb2O5 23.04
68 SiO2 37.35
69 Nb2O5 113.82
70 SiO2 158.36
71 Nb2O5 85.25
72 SiO2 75.02

Comparative Example 2
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 15.38
2 SiO2 30.98
3 Nb2O5 57.67
4 SiO2 23.94
5 Nb2O5 23.79
6 SiO2 97.67
7 Nb2O5 17.92
8 SiO2 30.75
9 Nb2O5 63.82
10 SiO2 46.28
11 Nb2O5 15.38
12 SiO2 75.48
13 Nb2O5 42.78
14 SiO2 25.62
15 Nb2O5 27.01
16 SiO2 113.30
17 Nb2O5 19.51
18 SiO2 30.75
19 Nb2O5 39.64
20 SiO2 163.91
21 Nb2O5 84.80
22 SiO2 151.54
23 Nb2O5 86.74
24 SiO2 33.52
25 Nb2O5 15.38
26 SiO2 45.62
27 Nb2O5 93.29
28 SiO2 147.13
29 Nb2O5 86.07
30 SiO2 147.27
31 Nb2O5 94.66
32 SiO2 56.66
33 Nb2O5 15.38
34 SiO2 37.30
35 Nb2O5 84.03
36 SiO2 39.12
37 Nb2O5 15.38
38 SiO2 57.54
39 Nb2O5 99.89
40 SiO2 160.09
41 Nb2O5 99.61
42 SiO2 176.00
43 Nb2O5 108.43
44 SiO2 182.01
45 Nb2O5 109.79
46 SiO2 183.74
47 Nb2O5 110.39
48 SiO2 183.10
49 Nb2O5 110.53
50 SiO2 183.09
51 Nb2O5 109.97
52 SiO2 181.76
53 Nb2O5 108.76
54 SiO2 181.05
55 Nb2O5 105.08
56 SiO2 170.20
57 Nb2O5 96.29
58 SiO2 79.48

Comparative Example 3
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 SiO2 94.81
2 Nb2O5 10.48
3 SiO2 33.79
4 Nb2O5 102.05
5 SiO2 33.32
6 Nb2O5 19.56
7 SiO2 40.71
8 Nb2O5 110.44
9 SiO2 35.39
10 Nb2O5 18.71
11 SiO2 24.59
12 Nb2O5 96.29
13 SiO2 196.65
14 Nb2O5 16.05
15 SiO2 223.97
16 Nb2O5 13.32
17 SiO2 227.18
18 Nb2O5 16.59
19 SiO2 196.77
20 Nb2O5 79.59
21 SiO2 19.56
22 Nb2O5 21.98
23 SiO2 57.44
24 Nb2O5 119.21
25 SiO2 32.06
26 Nb2O5 126.82
27 SiO2 33.85
28 Nb2O5 125.23
29 SiO2 34.09
30 Nb2O5 126.07
31 SiO2 36.59
32 Nb2O5 124.86
33 SiO2 34.66
34 Nb2O5 119.49
35 SiO2 61.27
36 Nb2O5 21.29
37 SiO2 20.28
38 Nb2O5 77.19
39 SiO2 183.85
40 Nb2O5 27.08
41 SiO2 31.73
42 Nb2O5 12.97
43 SiO2 156.54
44 Nb2O5 115.14
45 SiO2 34.33
46 Nb2O5 124.38
47 SiO2 79.30
48 Nb2O5 12.14
49 SiO2 72.94
50 Nb2O5 22.51
51 SiO2 201.57
52 Nb2O5 106.89
53 SiO2 37.65
54 Nb2O5 13.77
55 SiO2 34.15
56 Nb2O5 104.51
57 SiO2 202.42
58 Nb2O5 14.97
59 SiO2 199.77
60 Nb2O5 100.80
61 SiO2 35.73
62 Nb2O5 14.97
63 SiO2 43.55
64 Nb2O5 100.83
65 SiO2 188.87
66 Nb2O5 15.30
67 SiO2 209.98
68 Nb2O5 20.25
69 SiO2 35.81
70 Nb2O5 15.62
71 SiO2 149.54
72 Nb2O5 93.93
73 SiO2 154.42
74 Nb2O5 27.07
75 SiO2 17.64
76 Nb2O5 35.17
77 SiO2 170.29
78 Nb2O5 96.88
79 SiO2 37.25
80 Nb2O5 16.06
81 SiO2 45.39
82 Nb2O5 103.42
83 SiO2 87.50

Comparative Example 3
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 10.22
2 SiO2 35.62
3 Nb2O5 102.34
4 SiO2 156.54
5 Nb2O5 87.14
6 SiO2 149.29
7 Nb2O5 106.00
8 SiO2 20.02
9 Nb2O5 105.21
10 SiO2 149.81
11 Nb2O5 95.01
12 SiO2 42.76
13 Nb2O5 19.36
14 SiO2 34.17
15 Nb2O5 204.24
16 SiO2 44.45
17 Nb2O5 15.13
18 SiO2 57.31
19 Nb2O5 116.83
20 SiO2 21.06
21 Nb2O5 113.61
22 SiO2 23.41
23 Nb2O5 18.19
24 SiO2 26.17
25 Nb2O5 105.37
26 SiO2 62.06
27 Nb2O5 13.73
28 SiO2 44.37
29 Nb2O5 199.88
30 SiO2 42.86
31 Nb2O5 14.37
32 SiO2 56.82
33 Nb2O5 102.26
34 SiO2 61.10
35 Nb2O5 15.10
36 SiO2 41.53
37 Nb2O5 210.79
38 SiO2 41.49
39 Nb2O5 20.40
40 SiO2 40.23
41 Nb2O5 215.61
42 SiO2 33.15
43 Nb2O5 21.37
44 SiO2 40.41
45 Nb2O5 95.54
46 SiO2 154.28
47 Nb2O5 112.66
48 SiO2 30.66
49 Nb2O5 31.57
50 SiO2 45.52
51 Nb2O5 28.05
52 SiO2 34.75
53 Nb2O5 108.26
54 SiO2 154.08
55 Nb2O5 88.11
56 SiO2 155.57
57 Nb2O5 100.53
58 SiO2 173.70
59 Nb2O5 105.39
60 SiO2 172.65
61 Nb2O5 107.21
62 SiO2 172.22
63 Nb2O5 98.85
64 SiO2 156.11
65 Nb2O5 102.42
66 SiO2 37.82
67 Nb2O5 24.49
68 SiO2 27.87
69 Nb2O5 207.40
70 SiO2 24.01
71 Nb2O5 25.02
72 SiO2 32.87
73 Nb2O5 102.86
74 SiO2 152.65
75 Nb2O5 83.67
76 SiO2 70.39

Example 1
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 16.34
2 SiO2 28.28
3 Nb2O5 64.83
4 SiO2 23.55
5 Nb2O5 30.30
6 SiO2 40.40
7 Nb2O5 112.82
8 SiO2 45.22
9 Nb2O5 15.15
10 SiO2 36.35
11 Nb2O5 95.45
12 SiO2 190.09
13 Nb2O5 16.10
14 SiO2 218.88
15 Nb2O5 15.15
16 SiO2 220.94
17 Nb2O5 18.97
18 SiO2 199.93
19 Nb2O5 54.05
20 SiO2 29.18
21 Nb2O5 23.30
22 SiO2 74.99
23 Nb2O5 116.94
24 SiO2 38.72
25 Nb2O5 124.35
26 SiO2 36.76
27 Nb2O5 124.83
28 SiO2 38.48
29 Nb2O5 124.23
30 SiO2 38.39
31 Nb2O5 123.75
32 SiO2 40.50
33 Nb2O5 114.51
34 SiO2 85.79
35 Nb2O5 20.64
36 SiO2 28.61
37 Nb2O5 53.60
38 SiO2 176.99
39 Nb2O5 28.74
40 SiO2 25.25
41 Nb2O5 15.15
42 SiO2 147.35
43 Nb2O5 89.39
44 SiO2 143.58
45 Nb2O5 89.74
46 SiO2 169.33
47 Nb2O5 21.40
48 SiO2 30.30
49 Nb2O5 15.15
50 SiO2 165.72
51 Nb2O5 106.58
52 SiO2 56.89
53 Nb2O5 15.15
54 SiO2 32.19
55 Nb2O5 91.52
56 SiO2 180.87
57 Nb2O5 27.05
58 SiO2 30.30
59 Nb2O5 15.15
60 SiO2 155.48
61 Nb2O5 95.56
62 SiO2 149.06
63 Nb2O5 98.23
64 SiO2 180.19
65 Nb2O5 121.78
66 SiO2 46.19
67 Nb2O5 16.93
68 SiO2 229.33
69 Nb2O5 107.14
70 SiO2 180.94
71 Nb2O5 129.41
72 SiO2 25.25
73 Nb2O5 28.00
74 SiO2 184.96
75 Nb2O5 100.23
76 SiO2 79.29

Example 1
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 14.55
2 SiO2 47.64
3 Nb2O5 22.99
4 SiO2 190.77
5 Nb2O5 115.18
6 SiO2 25.31
7 Nb2O5 116.76
8 SiO2 51.63
9 Nb2O5 14.55
10 SiO2 35.46
11 Nb2O5 90.76
12 SiO2 189.51
13 Nb2O5 15.45
14 SiO2 220.58
15 Nb2O5 14.55
16 SiO2 216.46
17 Nb2O5 16.15
18 SiO2 186.22
19 Nb2O5 87.09
20 SiO2 27.39
21 Nb2O5 15.78
22 SiO2 49.91
23 Nb2O5 101.61
24 SiO2 19.36
25 Nb2O5 16.15
26 SiO2 28.83
27 Nb2O5 105.70
28 SiO2 18.02
29 Nb2O5 17.32
30 SiO2 22.62
31 Nb2O5 119.51
32 SiO2 21.35
33 Nb2O5 131.68
34 SiO2 19.38
35 Nb2O5 123.47
36 SiO2 13.98
37 Nb2O5 22.41
38 SiO2 14.55
39 Nb2O5 120.63
40 SiO2 18.50
41 Nb2O5 120.55
42 SiO2 23.56
43 Nb2O5 18.17
44 SiO2 16.53
45 Nb2O5 115.62
46 SiO2 22.04
47 Nb2O5 117.29
48 SiO2 44.84
49 Nb2O5 18.62
50 SiO2 25.30
51 Nb2O5 86.10
52 SiO2 156.03
53 Nb2O5 84.32
54 SiO2 155.86
55 Nb2O5 105.01
56 SiO2 177.09
57 Nb2O5 109.00
58 SiO2 174.93
59 Nb2O5 106.74
60 SiO2 174.34
61 Nb2O5 98.98
62 SiO2 163.78
63 Nb2O5 94.55
64 SiO2 165.72
65 Nb2O5 100.46
66 SiO2 85.17

Example 2
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 16.34
2 SiO2 28.28
3 Nb2O5 64.83
4 SiO2 23.55
5 Nb2O5 30.30
6 SiO2 40.40
7 Nb2O5 112.82
8 SiO2 45.22
9 Nb2O5 15.15
10 SiO2 36.35
11 Nb2O5 95.45
12 SiO2 190.09
13 Nb2O5 16.10
14 SiO2 218.88
15 Nb2O5 15.15
16 SiO2 220.94
17 Nb2O5 18.97
18 SiO2 199.93
19 Nb2O5 54.05
20 SiO2 29.18
21 Nb2O5 23.30
22 SiO2 74.99
23 Nb2O5 116.94
24 SiO2 38.72
25 Nb2O5 124.35
26 SiO2 36.76
27 Nb2O5 124.83
28 SiO2 38.48
29 Nb2O5 124.23
30 SiO2 38.39
31 Nb2O5 123.75
32 SiO2 40.50
33 Nb2O5 114.51
34 SiO2 85.79
35 Nb2O5 20.64
36 SiO2 28.61
37 Nb2O5 53.60
38 SiO2 176.99
39 Nb2O5 28.74
40 SiO2 25.25
41 Nb2O5 15.15
42 SiO2 147.35
43 Nb2O5 89.39
44 SiO2 143.58
45 Nb2O5 89.74
46 SiO2 169.33
47 Nb2O5 21.40
48 SiO2 30.30
49 Nb2O5 15.15
50 SiO2 165.72
51 Nb2O5 106.58
52 SiO2 56.89
53 Nb2O5 15.15
54 SiO2 32.19
55 Nb2O5 91.52
56 SiO2 180.87
57 Nb2O5 27.05
58 SiO2 30.30
59 Nb2O5 15.15
60 SiO2 155.48
61 Nb2O5 95.56
62 SiO2 149.06
63 Nb2O5 98.23
64 SiO2 180.19
65 Nb2O5 121.78
66 SiO2 46.19
67 Nb2O5 16.93
68 SiO2 229.33
69 Nb2O5 107.14
70 SiO2 180.94
71 Nb2O5 129.41
72 SiO2 25.25
73 Nb2O5 28.00
74 SiO2 184.96
75 Nb2O5 100.23
76 SiO2 79.29

Example 2
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
Nb2O5 2.38

Layer Material Film thickness (nm)
1 Nb2O5 21.03
2 SiO2 31.00
3 Nb2O5 34.37
4 SiO2 180.97
5 Nb2O5 117.57
6 SiO2 24.25
7 Nb2O5 110.40
8 SiO2 40.51
9 Nb2O5 14.55
10 SiO2 43.14
11 Nb2O5 98.21
12 SiO2 24.25
13 Nb2O5 20.35
14 SiO2 33.41
15 Nb2O5 121.78
16 SiO2 24.73
17 Nb2O5 115.21
18 SiO2 24.25
19 Nb2O5 17.27
20 SiO2 29.59
21 Nb2O5 122.35
22 SiO2 24.25
23 Nb2O5 133.06
24 SiO2 24.25
25 Nb2O5 134.08
26 SiO2 24.25
27 Nb2O5 134.90
28 SiO2 24.25
29 Nb2O5 133.68
30 SiO2 24.25
31 Nb2O5 132.29
32 SiO2 26.35
33 Nb2O5 133.27
34 SiO2 24.25
35 Nb2O5 132.92
36 SiO2 24.25
37 Nb2O5 133.38
38 SiO2 24.25
39 Nb2O5 134.92
40 SiO2 24.25
41 Nb2O5 133.53
42 SiO2 24.25
43 Nb2O5 133.31
44 SiO2 26.21
45 Nb2O5 128.44
46 SiO2 33.18
47 Nb2O5 110.75
48 SiO2 147.03
49 Nb2O5 87.24
50 SiO2 176.66
51 Nb2O5 114.02
52 SiO2 24.25
53 Nb2O5 14.55
54 SiO2 175.10
55 Nb2O5 26.12
56 SiO2 27.24
57 Nb2O5 34.05
58 SiO2 168.35
59 Nb2O5 92.33
60 SiO2 164.19
61 Nb2O5 108.87
62 SiO2 179.05
63 Nb2O5 97.45
64 SiO2 150.95
65 Nb2O5 88.14
66 SiO2 72.29

Example 3
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
TiO2 2.39

Layer Material Film thickness (nm)
1 TiO2 9.16
2 SiO2 29.43
3 TiO2 95.11
4 SiO2 159.35
5 TiO2 85.78
6 SiO2 20.25
7 TiO2 20.88
8 SiO2 39.90
9 TiO2 108.96
10 SiO2 195.34
11 TiO2 11.36
12 SiO2 678.69
13 TiO2 11.21
14 SiO2 192.42
15 TiO2 99.02
16 SiO2 37.50
17 TiO2 14.79
18 SiO2 42.40
19 TiO2 115.31
20 SiO2 24.63
21 TiO2 128.14
22 SiO2 24.24
23 TiO2 128.40
24 SiO2 25.26
25 TiO2 129.56
26 SiO2 27.05
27 TiO2 125.56
28 SiO2 31.34
29 TiO2 113.94
30 SiO2 80.27
31 TiO2 12.39
32 SiO2 31.73
33 TiO2 77.37
34 SiO2 185.56
35 TiO2 23.60
36 SiO2 185.81
37 TiO2 64.17
38 SiO2 19.91
39 TiO2 13.83
40 SiO2 117.13
41 TiO2 96.53
42 SiO2 139.71
43 TiO2 13.27
44 SiO2 37.62
45 TiO2 30.27
46 SiO2 188.60
47 TiO2 103.49
48 SiO2 29.02
49 TiO2 18.48
50 SiO2 38.05
51 TiO2 108.82
52 SiO2 197.19
53 TiO2 19.31
54 SiO2 194.83
55 TiO2 86.27
56 SiO2 23.28
57 TiO2 18.11
58 SiO2 53.39
59 TiO2 110.09
60 SiO2 60.43
61 TiO2 20.65
62 SiO2 24.11
63 TiO2 70.07
64 SiO2 159.63
65 TiO2 82.41
66 SiO2 48.23
67 TiO2 11.26
68 SiO2 63.43
69 TiO2 81.18
70 SiO2 20.53
71 TiO2 21.66
72 SiO2 50.41
73 TiO2 107.83
74 SiO2 208.64
75 TiO2 18.66
76 SiO2 42.12
77 TiO2 112.95
78 SiO2 165.54
79 TiO2 89.71
80 SiO2 77.84

Example 3
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
TiO2 2.39

Layer Material Film thickness (nm)
1 TiO2 10.05
2 SiO2 34.19
3 TiO2 97.80
4 SiO2 153.99
5 TiO2 86.57
6 SiO2 151.02
7 TiO2 105.53
8 SiO2 19.19
9 TiO2 113.00
10 SiO2 56.42
11 TiO2 12.87
12 SiO2 51.09
13 TiO2 100.27
14 SiO2 17.08
15 TiO2 26.39
16 SiO2 32.21
17 TiO2 32.55
18 SiO2 47.26
19 TiO2 22.20
20 SiO2 48.91
21 TiO2 108.20
22 SiO2 70.03
23 TiO2 11.45
24 SiO2 47.32
25 TiO2 200.40
26 SiO2 41.57
27 TiO2 14.77
28 SiO2 60.07
29 TiO2 105.16
30 SiO2 58.44
31 TiO2 15.70
32 SiO2 43.57
33 TiO2 196.62
34 SiO2 161.54
35 TiO2 85.75
36 SiO2 18.19
37 TiO2 21.35
38 SiO2 54.77
39 TiO2 25.45
40 SiO2 45.46
41 TiO2 31.68
42 SiO2 36.17
43 TiO2 116.54
44 SiO2 54.43
45 TiO2 17.42
46 SiO2 42.47
47 TiO2 203.30
48 SiO2 48.00
49 TiO2 12.03
50 SiO2 68.49
51 TiO2 104.90
52 SiO2 52.83
53 TiO2 18.34
54 SiO2 37.92
55 TiO2 202.90
56 SiO2 38.40
57 TiO2 19.27
58 SiO2 48.13
59 TiO2 96.33
60 SiO2 155.44
61 TiO2 92.57
62 SiO2 173.19
63 TiO2 103.66
64 SiO2 173.53
65 TiO2 103.50
66 SiO2 174.04
67 TiO2 102.01
68 SiO2 164.17
69 TiO2 90.66
70 SiO2 161.13
71 TiO2 113.04
72 SiO2 31.81
73 TiO2 29.18
74 SiO2 51.13
75 TiO2 26.04
76 SiO2 36.69
77 TiO2 109.39
78 SiO2 155.58
79 TiO2 85.88
80 SiO2 150.37
81 TiO2 83.25
82 SiO2 72.86

Example 4
Multilayer MA (A surface)
n (540nm)
Board 1.52
SiO2 1.47
TiO2 2.39

Layer Material Film thickness (nm)
1 SiO2 54.59
2 TiO2 9.90
3 SiO2 35.25
4 TiO2 107.25
5 SiO2 35.16
6 TiO2 21.40
7 SiO2 23.47
8 TiO2 91.88
9 SiO2 189.41
10 TiO2 19.76
11 SiO2 214.64
12 TiO2 20.27
13 SiO2 192.62
14 TiO2 72.68
15 SiO2 19.67
16 TiO2 26.11
17 SiO2 50.06
18 TiO2 121.81
19 SiO2 27.69
20 TiO2 128.55
21 SiO2 24.37
22 TiO2 129.54
23 SiO2 23.31
24 TiO2 129.71
25 SiO2 22.52
26 TiO2 130.03
27 SiO2 21.83
28 TiO2 130.18
29 SiO2 20.98
30 TiO2 130.68
31 SiO2 21.97
32 TiO2 130.13
33 SiO2 25.70
34 TiO2 121.99
35 SiO2 56.45
36 TiO2 23.71
37 SiO2 24.89
38 TiO2 69.60
39 SiO2 189.30
40 TiO2 23.96
41 SiO2 211.37
42 TiO2 22.52
43 SiO2 212.72
44 TiO2 23.32
45 SiO2 201.67
46 TiO2 42.44
47 SiO2 29.81
48 TiO2 22.29
49 SiO2 288.86
50 TiO2 15.75
51 SiO2 20.02
52 TiO2 75.03
53 SiO2 168.01
54 TiO2 69.30
55 SiO2 17.58
56 TiO2 20.89
57 SiO2 236.37
58 TiO2 11.40
59 SiO2 31.79
60 TiO2 100.20
61 SiO2 176.11
62 TiO2 113.67
63 SiO2 186.72
64 TiO2 113.29
65 SiO2 187.39
66 TiO2 114.15
67 SiO2 182.70
68 TiO2 124.66
69 SiO2 37.51
70 TiO2 17.76
71 SiO2 158.83
72 TiO2 9.94
73 SiO2 32.29
74 TiO2 82.85
75 SiO2 24.80
76 TiO2 19.07
77 SiO2 74.29
78 TiO2 21.29
79 SiO2 16.41
80 TiO2 78.08
81 SiO2 86.14

Example 4
Multilayer MB (B side)
n (540nm)
Board 1.52
SiO2 1.47
TiO2 2.39

Layer Material Film thickness (nm)
1 TiO2 10.15
2 SiO2 34.31
3 TiO2 102.29
4 SiO2 158.00
5 TiO2 85.29
6 SiO2 150.91
7 TiO2 87.84
8 SiO2 35.67
9 TiO2 15.31
10 SiO2 41.05
11 TiO2 89.48
12 SiO2 146.05
13 TiO2 80.84
14 SiO2 143.54
15 TiO2 80.59
16 SiO2 145.35
17 TiO2 93.20
18 SiO2 46.82
19 TiO2 22.36
20 SiO2 31.17
21 TiO2 58.41
22 SiO2 45.47
23 TiO2 11.33
24 SiO2 74.10
25 TiO2 88.06
26 SiO2 142.90
27 TiO2 81.55
28 SiO2 142.88
29 TiO2 82.87
30 SiO2 147.03
31 TiO2 91.50
32 SiO2 179.06
33 TiO2 26.19
34 SiO2 12.57
35 TiO2 80.35
36 SiO2 20.26
37 TiO2 10.15
38 SiO2 146.29
39 TiO2 92.57
40 SiO2 145.43
41 TiO2 21.58
42 SiO2 16.24
43 TiO2 40.24
44 SiO2 167.77
45 TiO2 104.56
46 SiO2 32.72
47 TiO2 14.04
48 SiO2 91.76
49 TiO2 10.15
50 SiO2 47.83
51 TiO2 100.80
52 SiO2 155.22
53 TiO2 90.33
54 SiO2 148.68
55 TiO2 11.92
56 SiO2 15.22
57 TiO2 304.64
58 SiO2 26.97
59 TiO2 26.25
60 SiO2 41.89
61 TiO2 112.25
62 SiO2 77.59
63 TiO2 10.15
64 SiO2 51.91
65 TiO2 212.68
66 SiO2 40.31
67 TiO2 20.94
68 SiO2 47.55
69 TiO2 106.09
70 SiO2 18.40
71 TiO2 10.15
72 SiO2 179.85
73 TiO2 15.07
74 SiO2 16.31
75 TiO2 92.24
76 SiO2 168.29
77 TiO2 64.07
78 SiO2 17.50
79 TiO2 19.39
80 SiO2 108.52
81 TiO2 21.10
82 SiO2 21.61
83 TiO2 50.42
84 SiO2 85.10

FR Infrared cut filter MA, MB Dielectric multilayer film SU substrate DU Digital equipment LU Imaging optical device (camera unit)
LN Imaging lens SR Imaging element SS Light receiving surface (imaging surface)
IM image plane (optical image)
AX Optical axis 1 Signal processing unit 2 Control unit 3 Memory 4 Operation unit 5 Display unit

Claims

An infrared cut filter having a dielectric multilayer film on both sides of a substrate,
The average transmittance at an incident angle of 0 degree at a wavelength of 425 to 620 nm is 95% or more,
The average transmittance at an incident angle of 30 degrees at a wavelength of 425 to 620 nm is 94% or more,
The average transmittance at an incident angle of 0 degree at a wavelength of 600 to 620 nm is 91% or more,
The following conditional expressions (1) and (2) are satisfied at a wavelength of 580 to 700 nm,
The average transmittance at a wavelength of 700 to 1100 nm is 0.5% or less and the maximum transmittance is 1.8% or less,
An infrared cut filter having an average transmittance of 8% or less at a wavelength of 1100 to 1200 nm and a maximum transmittance of 12.5% or less;
Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degree) | <400 (1)
Σ [T = 5 to 50%] | λT (0 degree) −λT (30 degree) | <850 (2)
However,
Σ [T = a˜b%] | λT (0 degree) −λT (30 degree) |: Wavelength difference for every 1% from the transmittance T of a% to b% | λT (0 degree) −λT (30 Degree) |
λT (θ): wavelength (nm) at an incident angle θ degree and transmittance T%,
It is.
Of the two filter surfaces comprising the dielectric multilayer films on both surfaces of the substrate at a wavelength of 580 to 700 nm, the surface with the shorter wavelength when the incident angle is 0 degree and the transmittance is 50% is the A surface, and the longer surface is The infrared cut filter according to claim 1, which satisfies the following conditional expression (3) as the B surface:
−15 ≦ λA 50% (0 degree) −λB 50% (30 degree) ≦ 10 (3)
However,
λA 50% (0 degree): wavelength (nm) when the incident angle is 0 degree on the A plane and the transmittance is 50%,
λB50% (30 degrees): wavelength (nm) at an incident angle of 30 degrees and a transmittance of 50% on the B surface,
It is.
The average transmittance at an incident angle of 0 degree at a wavelength of 425 to 620 nm is 99% or more,
The average transmittance at an incident angle of 30 degrees at a wavelength of 425 to 620 nm is 97% or more,
The infrared cut filter according to claim 1 or 2, wherein the average transmittance at an incident angle of 0 degree at a wavelength of 600 to 620 nm is 98.5% or more.
The infrared cut filter according to any one of claims 1 to 3, which satisfies the following conditional expression (1a) at a wavelength of 580 to 700 nm:
Σ [T = 50 to 90%] | λT (0 degree) −λT (30 degree) | <215 (1a)
However,
Σ [T = a˜b%] | λT (0 degree) −λT (30 degree) |: Wavelength difference for every 1% from the transmittance T of a% to b% | λT (0 degree) −λT (30 Degree) |
λT (θ): wavelength (nm) at an incident angle θ degree and transmittance T%,
It is.
The average transmittance at a wavelength of 700 to 1100 nm is 0.15% or less and the maximum transmittance is 1% or less,
The infrared cut filter according to any one of claims 1 to 4, wherein an average transmittance at a wavelength of 1100 to 1200 nm is 4% or less and a maximum transmittance is 9% or less.
The average transmittance at a wavelength of 700 to 1100 nm is 0.1% or less and the maximum transmittance is 0.7% or less,
6. The infrared cut filter according to claim 1, wherein an average transmittance at a wavelength of 1100 to 1200 nm is 1% or less and a maximum transmittance is 1.5% or less.
A camera unit comprising the infrared cut filter according to any one of claims 1 to 6.