JP2021009271A - Camera module and electronic equipment - Google Patents

Abstract

To provide an optical filter capable of coping with both of suppression of flare of a camera image, and suppression of color shading and that of ghost at a high level.SOLUTION: A camera module 100x includes: an optical lens group 104x disposed in an incidence side of light; an image pickup device 106x for receiving light that enters via the optical lens group; a near-infrared light reflection part for reflecting light in a near-infrared region; and a near-infrared light absorption part for absorbing light in a near-infrared region. The near-infrared light absorption part contains a cycloolefin resin having a refractive index of 1.52 or larger and less than 1.54, and a compound for absorbing near infrared rays.SELECTED DRAWING: Figure 2

Description

One embodiment of the present invention relates to an optical configuration of a camera module and an electronic device using the camera module.

Electronic devices such as video cameras, digital still cameras, and mobile phones with a camera function use CCDs and CMOS image sensors as solid-state image sensors capable of capturing color images. For these solid-state image sensors, a silicon photodiode having sensitivity to near infrared rays, which cannot be perceived by the human eye, is used in the light receiving portion thereof. Since silicon photodiodes have light sensitivity up to the near-infrared wavelength region, it is necessary for solid-state image sensors to perform visual sensitivity correction that makes the colors look natural to the human eye, and light rays in a specific wavelength region are selected. An optical filter (for example, a near-infrared cut filter) that transmits or cuts light is often used.

As the near-infrared cut filter, those manufactured by various methods have been conventionally used. For example, a near-infrared cut filter in which a transparent resin is used as a base material and a near-infrared absorbing dye is contained in the transparent resin is known (see, for example, Patent Document 1). However, the near-infrared cut filter described in Patent Document 1 may not always have sufficient near-infrared absorption characteristics.

Patent Document 2 discloses a near-infrared cut filter having a wide viewing angle and high visible light transmittance. Further, Patent Document 3 discloses a near-infrared cut filter that achieves both excellent visible transmittance and lengthening of the absorption maximum wavelength at a high level by using a phthalocyanine dye having a specific structure. However, in the near-infrared cut filters described in Patent Documents 2 and 3, although the applied base material has a sufficiently strong absorption band near a wavelength of 700 nm, the near-infrared rays such as 900 nm to 1200 nm are used. It has almost no absorption in the wavelength region. Therefore, the light rays in the near-infrared wavelength region are cut almost only by the reflection of the dielectric multilayer film, but in such a configuration, a slight stray light due to the internal reflection in the optical filter and the reflection between the optical filter and the lens. However, it may cause ghosts and flares when shooting in a dark environment. In particular, in recent years, there has been a strong demand for higher image quality of cameras even in mobile devices such as smartphones, and conventional optical filters may not be suitable for use.

On the other hand, as an optical filter using a base material having a wide absorption in the near infrared wavelength region, an infrared shielding filter as disclosed in Patent Document 4 has been proposed. In Patent Document 4, a wide absorption in the near-infrared wavelength region is achieved by mainly applying a compound having a dithiolene structure, but the absorption intensity near 700 nm is not sufficient.

Further, Patent Document 5 discloses a camera module in which a cover glass having a characteristic of reflecting light in a specific wavelength band by a dielectric multilayer film and a near-infrared light absorbing unit are combined. However, while the camera module of Patent Document 5 has the effect of suppressing the near-infrared rays transmitted through the cover glass, the incident near-infrared rays are emitted from the surface of the near-infrared light absorbing portion when shooting under a light source having a strong near-infrared light. The ghost that occurs due to the reflection on the infrared ray and the reflection on the cover glass again has become a problem.

Japanese Unexamined Patent Publication No. 6-200113 Japanese Unexamined Patent Publication No. 2011-100084 International Publication 2015/025779 Pamphlet International Publication 2014/168190 Pamphlet International Publication No. 2018/155634 Pamphlet

In addition to the above-mentioned problems, for the purpose of further improving the performance of the camera module, it has been studied to configure the functions of a conventional optical filter that combines absorption by a dye and reflection by a dielectric multilayer film with separate members for each function. Therefore, there is a demand for an optical filter capable of supporting such a configuration.

One embodiment of the present invention provides a camera module having an optical filter capable of suppressing flare, color shading, and ghost of a camera image at a high level, which cannot be sufficiently achieved by a conventional optical filter. Make it an issue.

The camera module according to the embodiment of the present invention reflects light in the near-infrared region, an optical lens group arranged on the incident side of light, an image pickup element that receives light incident through the optical lens group, and light in the near infrared region. It includes a cover glass having a near-infrared light reflecting portion and a near-infrared light absorbing portion that absorbs light in the near-infrared region. The near-infrared light absorbing unit includes a cycloolefin resin having a refractive index of 1.52 or more and less than 1.54, and a compound that absorbs near-infrared rays.

In the near-infrared light reflecting unit and the near-infrared light absorbing unit, the near-infrared light reflecting unit and the near-infrared light absorbing unit may be arranged in order from the light incident side. The near-infrared light reflecting portion includes a glass base material, an antireflection layer that prevents light in the visible region from being reflected on at least one surface of the glass base material, and a reflection layer that reflects light in the near infrared region. It may be included. In the near-infrared light absorption unit, the compound may be dispersed in the cycloolefin resin. The near-infrared light absorbing unit may have an antireflection layer for preventing reflection of light in the visible light region on the incident surface of light.

The camera module according to the embodiment of the present invention preferably satisfies the following requirements (1) and (2).
Requirements (1) R _NIR-5 <30
Requirement (2) R _NIR-30 <30
here,
RA5 (λ): Reflectance when incident on the optical filter at wavelength λ nm at 5 degrees from the optical lens group side RB5 (λ): Reflectance when incident on the cover glass at wavelength λ nm at 5 degrees from the optical lens group side And
RA30 (λ): Reflectance when incident on the optical filter at wavelength λ nm at 30 degrees from the optical lens group side RB30 (λ): Reflectance when incident on the cover glass at wavelength λ nm at 30 degrees from the optical lens group side Is.

The camera module according to the embodiment of the present invention preferably further satisfies the following requirements (3) and (4).
Requirements (3) T _NIR-5 <30
Requirement (4) T _NIR-30 <30
here,
TA5 (λ): Transmittance when incident on the optical filter at wavelength λ nm at 5 degrees from the optical lens group side TB5 (λ): When incident on the cover glass at wavelength λ nm at 5 degrees from the opposite side of the optical lens group Is the transmittance of
TA30 (λ): Transmittance when incident on the optical filter at wavelength λ nm at 30 degrees from the optical lens group side TB30 (λ): Transmittance on the cover glass at wavelength λ nm at 30 degrees from the side opposite to the optical lens group side The transmittance of the lens.

The compound that absorbs near infrared rays may be at least one compound selected from the group consisting of a squarylium compound, a phthalocyanine compound, a naphthalocyanine compound, a croconium compound, and a cyanine compound.

The optical filter preferably has a maximum absorption wavelength in the wavelength range of 650 nm to 800 nm. The optical filter contains a compound having an absorption maximum in the wavelength region of 650 m or more and 715 nm or less, the compound being a squarylium compound, a compound having an absorption maximum in the wavelength region of more than 715 nm and 750 nm or less is a phthalocyanine compound, and a wavelength of more than 750 nm and 800 nm. The compound having the absorption maximum in the following regions is preferably a squarylium-based compound.

According to one embodiment of the present invention, a camera module having excellent near-infrared cut characteristics, less dependence on incident angle, and excellent transmittance characteristics in the visible wavelength range, flare suppression effect, color shading suppression effect, and ghost suppression effect. Can be provided.

It is a figure which showed the structure which measures the transmission spectrum from the vertical direction, the diagonal 30 degree direction, and the reflection spectrum from the diagonal 5 degree direction, and the oblique 30 degree direction. It is a schematic diagram which showed the structure of the camera module used for the flare evaluation, the color shading evaluation, and the ghost performed in an Example and a comparative example. It is a figure explaining the mechanism which ghost occurs in a camera module. It is a schematic diagram for demonstrating the color shading evaluation of the camera image performed in an Example and a comparative example. It is a schematic diagram for demonstrating the flare evaluation of the camera image performed in an Example and a comparative example. It is a schematic diagram for demonstrating the ghost evaluation of the camera image performed in an Example and a comparative example. It is a spectral transmission / reflection spectrum of the optical filter obtained in Example 1. It is a spectral transmission / reflection spectrum of the optical filter obtained in Example 2. 3 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 3. It is a spectral transmission / reflection spectrum of the optical filter obtained in Example 4. 6 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 5. 6 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 6. 6 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 7. 6 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 8. 9 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 10. 9 is a spectral transmission / reflection spectrum of the optical filter obtained in Example 11. It is a spectral transmission / reflection spectrum of the optical filter obtained in Comparative Example 1. It is a spectral transmission / reflection spectrum of the optical filter obtained in Comparative Example 2. It is a spectral transmission / reflection spectrum of the optical filter obtained in Comparative Example 3. It is a figure which shows the structure of the camera module which concerns on one Embodiment of this invention. It is a figure which shows the structure of the cover glass which concerns on one Embodiment of this invention. It is a figure which shows the structure of the optical filter which concerns on one Embodiment of this invention. It is a figure which shows the structure of the image pickup device which concerns on one Embodiment of this invention.

Embodiments of the present invention will be described with reference to drawings and the like. However, the present invention can be implemented in many different modes and is not construed as being limited to the description of the embodiments illustrated below. In order to clarify the explanation, the drawings may schematically represent the width, thickness, shape, etc. of each part as compared with the actual embodiment, but this is merely an example and limits the interpretation of the present invention. It's not a thing. Further, in the present specification and each figure, the same elements as those described above with respect to the above-mentioned figures are designated by the same reference numerals or similar reference numerals (signatures in which a, b, etc. are simply added after the numbers). The detailed description may be omitted as appropriate.

Hereinafter, an optical filter according to an embodiment of the present invention, a camera module using the optical filter, and an electronic device having the camera module will be described in detail.

1. 1. Camera module The camera module 100 according to the embodiment of the present invention includes a near-infrared light reflecting unit 108 and a near-infrared light absorbing unit 110 in addition to the optical lens group 104 and the image sensor 106. Hereinafter, the configuration of the camera module 100 will be described with reference to FIG.

1-1. Configuration of Camera Module FIG. 20 shows the configuration of the camera module 100 according to the embodiment of the present invention. The camera module 100 includes an optical lens group 104, a housing 102 in which the optical lens group 104 is housed, an image pickup element 106 provided on the side of the optical lens group 104 opposite to the light incident side, an optical lens group 104, and an image pickup element 106. It includes a near-infrared light absorbing unit 110 provided between the two, and a near-infrared light reflecting unit 108 provided on the front surface of the incident surface of the optical lens group 104. The housing 102, the optical filter 111, and the image sensor 106 may be housed or supported in the casing 103. The camera module 100 has a configuration in which a near-infrared light reflecting unit 108, an optical lens group 104, a near-infrared light absorbing unit 110, and an image sensor 106 are arranged from the incident side of external light. The near-infrared light reflecting unit 108 and the near-infrared light absorbing unit 110 are arranged so as to cover at least a part, preferably the entire surface, of the light receiving surface of the image sensor 106 when the image sensor 106 is viewed from the light incident side. To. The camera module 100 is configured by the housing 102 and the casing 103 so that stray light does not enter the image sensor 106 from the outside.

The configuration of the optical lens group 104 shown in FIG. 20 is an example, and one embodiment of the present invention is not construed as being limited to the configuration of the lens as shown. Further, although not shown in FIG. 20, the camera module 100 may be provided with a drive mechanism for zooming the lens.

1-2. Structure of Near Infrared Light Reflecting Unit The near infrared light reflecting unit 108 is configured to include an optical thin film that reflects light in the near infrared region. Further, the near-infrared light reflecting unit 108 is configured to include an optical thin film that prevents reflection of light in the visible light wavelength region. The near-infrared light reflecting unit 108 has a structure in which these optical thin films are provided on a translucent base material. The function of the near-infrared light reflecting unit 108 is realized by, for example, a cover glass provided on the light incident side of the camera module 100.

FIG. 21 shows the configuration of the cover glass 109 having a function as a near-infrared light reflecting portion 108 of the camera module 100 according to the embodiment of the present invention. FIG. 21A shows an antireflection layer 122 that prevents reflection of light in the visible light wavelength region, a reflection layer 124 that reflects near-infrared light, and reflection having an antireflection effect on light having a wavelength of 700 nm to 1200 nm. The prevention layer 114 and the cover glass 109a provided on the transparent base material 120 are shown. In the cover glass 109a, the members of the antireflection layer 122, the reflection layer 124, the transparent base material 120, and the antireflection layer 114 are arranged in this order from the light incident side. That is, the transparent base material 120 has a structure in which the antireflection layer 122 and the reflection layer 124 are provided on the surface on the side where the external light is incident, and the antireflection layer 114 is provided on the surface on the opposite side. The antireflection layer 122 for preventing the reflection of light in the visible light wavelength region and the reflection layer 124 for reflecting near infrared light are each formed of a dielectric multilayer film. As the transparent base material 120, for example, crystallized glass is used to increase the transmittance of visible light. Further, an antifouling layer may be provided on the surface of the antireflection layer 122 of the cover glass 109 to prevent stains.

The cover glass 109b shown in FIG. 21B is different in that the reflective layer 124 that reflects near-infrared light is provided between the transparent base material 120 and the antireflection layer 114, but each member constitutes the cover glass 109b. The same as the cover glass 109a shown in FIG. 21 (A) is used. In the cover glasses 109a and 109b, the surface reflection of incident external light is suppressed by the action of the antireflection layer 122, and the near-infrared light among the external light components is reflected by the action of the reflection layer 124. Further, the light in the visible light wavelength region incident from the back surfaces of the cover glasses 109a and 109b (the surface opposite to the light incident side) is suppressed from being reflected on the surface of the transparent base material 116 by the action of the antireflection layer 114. To.

1-3. Structure of Near Infrared Light Absorbing Unit The near infrared light absorbing unit 110 is configured to include a transparent resin layer containing a compound that absorbs light in the near infrared region. Further, the near-infrared light absorption unit 110 includes an optical thin film that prevents reflection of light in the visible light wavelength region. The near-infrared light reflecting unit 108 has a structure in which these members are provided on a translucent base material. The function of the near-infrared light absorption unit 110 is realized by, for example, an optical filter provided in the camera module 100.

FIG. 22 shows the configuration of the optical filter 111 having a function as a near-infrared light absorbing unit 110 of the camera module 100 according to the embodiment of the present invention. FIG. 22A shows an optical filter 111a having a transparent resin base material 112 containing a compound that absorbs near infrared rays and an antireflection layer 114 having an antireflection effect on light having a wavelength of 700 nm to 1200 nm. The transparent resin base material 112 is formed in a flat plate shape, and the compound that absorbs near infrared rays is dispersed and contained in the transparent resin base material 112. The antireflection layer 114 is provided on the surface of the transparent resin base material 112 on the light incident side. The near-infrared light incident on the optical filter 111a hardly reflects due to the effect of the antireflection layer 114, enters the transparent resin base material 112, and is absorbed in the transparent resin base material 112. On the other hand, the transparent resin base material 112 has a property of hardly absorbing and transmitting light in the visible light wavelength region. As a result, the optical filter 111a has a property of transmitting light in the visible light wavelength region and absorbing near-infrared light without scattering.

FIG. 22B shows a transparent base material 116 formed of glass or the like, a transparent resin layer 118 containing a compound that absorbs near infrared rays, and an antireflection layer 114 having an antireflection effect on light having a wavelength of 700 nm to 1200 nm. The optical filter 111b having the above is shown. The transparent resin layer 118 is provided on the surface of the transparent base material 116 on the light incident side. Further, the antireflection layer 114 is provided on the surface of the transparent resin layer 118 on the light incident side. FIG. 22C shows an optical filter 111c having a structure in which a transparent resin layer 118 containing a compound that absorbs near infrared rays is provided on a surface of the transparent base material 116 opposite to the light incident surface. The antireflection layer 114 having an antireflection effect on light having a wavelength of 700 nm to 1200 nm is provided directly on the surface of the transparent base material 116 on the light incident side. Although the optical filter 111b shown in FIG. 22B and the optical filter 111c shown in FIG. 22C contain a transparent base material 116 with respect to the optical filter 111a shown in FIG. 22A, the transparent resin layer 118 and the reflection are included. It has the property of transmitting light in the visible light wavelength region by the action of the prevention layer 114 and absorbing near-infrared light without scattering.

The transparent resin base material 112 and the transparent resin layer 118 are preferably cycloolefin resins having a refractive index of 1.52 or more and less than 1.54. General optical glass can be used for the transparent base material 116. Examples of general optical glass include BK7 (manufactured by SCHOTT, refractive index 1.52) and D263 (manufactured by SCHOTT, refractive index 1.52).

When a difference in refractive index occurs between the two components of the interface, reflected light is generated according to Fresnel's equations. By using a cycloolefin resin having a refractive index within the above range, it is possible to reduce the reflected light of the laminate when the general optical glass is used as a transparent base material, and the ghost of the obtained imaging device can be reduced. It can be suppressed. The transparent resin base material 112 and the transparent resin layer 118 are more preferably cycloolefin resins having a refractive index of 1.52 or more and 1.53 or less. The refractive index shown here is a wavelength of 589 nm at 23 ° C. using a prism coupler model 2010 (manufactured by Metrocon) and a test piece having a width of 8 mm, a length of 20 mm, and a thickness of 3 mm according to JIS K7142: 2014. The refractive index n _D measured by using the light beam of.

1-4. Image sensor The image sensor 106 is realized by a CMOS image sensor, a CCD image sensor, or the like. These image sensors include a photodiode that constitutes a pixel, a signal reading circuit, and the like. An example of the image sensor 106 is shown below.

FIG. 23 shows the cross-sectional structure of the pixel 126 of the image sensor 106 used in the camera module 100. The pixel 126 includes a photodiode 128 (128r, 128g, 128b) as a light receiving element. A color filter layer 130 and a microlens array 132 are provided on the light receiving surface of the photodiode 128. Further, when the image pickup device 106 is a surface incident type, a wiring layer 134 is provided between the photodiode 128 and the color filter layer 130. The wiring layer 134 is a layer including wiring provided in the pixel 126, such as an address line and a signal line. In the wiring layer 134, a plurality of wirings may be separated by an interlayer insulating film to form multiple layers. In a normal case, the address line and the signal line extend in the row direction and the column direction and intersect with each other, so that they are provided in different layers with an interlayer insulating film in between.

The color filter layer 130 is provided with a red color filter layer 130r, a green color filter layer 130g, and a blue color filter layer 130b so that a color image can be captured. The color filter layer 130 has a transmission spectrum corresponding to each color. For example, the red color filter layer 130r has a characteristic of transmitting not only the red light band but also the near infrared light band.

The photodiode 128 is formed on a semiconductor substrate. As the semiconductor substrate, for example, a silicon substrate, a substrate in which a silicon layer is provided on an insulating layer (SOI substrate), or the like is used. The photodiode 128 includes a semiconductor junction by a pn junction or a pin junction, and converts incident light into an electric signal by the photoelectric effect. The photodiode 128 has optical sensitivity over a wide band from visible light to near-infrared light, depending on the physical characteristics of the silicon semiconductor.

As shown in FIG. 21, in the camera module 100 according to the present embodiment, an optical filter 111 having a function of blocking near infrared rays is arranged on the light incident surface side of the image sensor 106. The optical filter 111 attenuates the near-infrared light transmitted through the optical lens group 104 and contributes to the improvement of the dynamic range of the image sensor 106. Further, as will be described later, the optical filter 111 can significantly suppress the influence of ghosts.

2. 2. Requirements to be Satisfied by the Camera Module In the camera module 100, the light incident on the light receiving surface of the image sensor 106 includes direct light and scattered incident light. When the influence of the scattered incident light on the direct light cannot be ignored, the occurrence of ghost is visually recognized in the image captured by the camera module 100. In this section, first, the direct light and the scattered incident light incident on the light receiving surface of the image sensor 106 will be considered.

2-1. Ghost Generation Mechanism FIG. 2 shows a configuration example of the camera module 100. FIG. 2A shows an optical lens group 104x housed in a housing 102x, an optical filter 111x as a near-infrared light absorbing unit, and an image sensor 106x. FIG. 2B shows a configuration in which a cover glass 109x as a near-infrared light reflecting portion is arranged in front of the optical lens group 104x on the light incident side. FIG. 2C shows an embodiment in which the optical filter 111x is arranged in the optical lens group 104x. In FIG. 2C, the optical filter 111x is located between the fourth and fifth elements of the optical lens group 104x, but it may be designed to be provided at other positions. From the viewpoint of ease of designing a lens group with less wavelength dispersion, the optical filter 111x is between the second and third lenses of the optical lens group 104x, between the third and fourth lenses, and the fourth and fifth lenses. It is preferable to have it between. As the optical lens group 104x, the incident angle (CRA) of the main light beam that can be tolerated by the pixels on the light receiving surface of the sensor is 30 to 60 degrees.

3 (A) and 3 (B) show an example of a mechanism in which ghosts occur in the camera module 100x having the configuration shown in FIG. 2 (B). In FIG. 3A, after the external light passes through the cover glass 109x, the light incident from the optical lens group 104x is reflected on the surface of the optical filter 111x, and the reflected light is again incident on the surface of the cover glass 109x and reflected. An example of a ghost generated by passing through the optical filter 111x and incident on the image pickup element 106x is shown. FIG. 3B shows a case where the incident angle of the external light incident on the cover glass 109x is larger than that of FIG. 3A. When the incident angle of external light is large, a part of the light incident from the optical lens group 104x on the surface of the optical filter 111x becomes reflected light, but since the incident angle is large, it is complicatedly reflected in the housing 102x. Then, the reflected light is incident on the surface of the cover glass 109x again and is reflected again, and then is transmitted through the optical filter 111x and incident on the image pickup element 106x to generate a ghost. In particular, in the optical lens group 104x having a CRA of 34 degrees or more, the curvature of the lens is large and complicated reflection tends to occur.

By suppressing the reflectance of light incident on the cover glass 109x from the optical lens group 104x and the reflectance of light incident on the optical filter 111x from the optical lens group 104x to R _NIR-0 and R _NIR-30 low. , Ghosts generated in the optical path as shown in FIG. 3A can be effectively reduced. Further, the T _NIR-0 and T _NIR-30 obtained from the transmittance of the light incident on the cover glass 109x from the optical lens group 104x and the transmittance of the light incident on the optical filter 111x from the optical lens group 104x are suppressed to be low. As a result, ghosts generated in the optical path as shown in FIG. 3B can be effectively reduced. In particular, it is preferable to use it in combination with an optical lens group 104x having a CRA of 34 degrees or more, and even more preferably to use it in combination with an optical lens group 104x having a CRA of 40 degrees or more.

As shown in FIG. 3A, when the incident light is small, the difference between the position of the direct light 21 on the image sensor 106x and the position of the scattered incident light 22 is small, and the influence of the ghost is small. On the other hand, as shown in FIG. 3B, when the incident light is large, the difference between the position of the direct light 23 to the image sensor 106x and the position of the scattered incident light 24 is large, and the influence of ghost is large. It will be easier. In reality, when the incident angle of external light is about 5 degrees or more, the influence of ghosts often becomes a problem.

Some camera modules have an optical lens group designed so that the incident angle of the light incident on the optical filter includes an optical path of about 35 degrees. When the angle of incidence on the optical filter is about 35 degrees, the effect of the light reflected from the surface of the optical filter being scattered inside the housing and re-incident is small, but when the angle of incidence on the optical filter is about 30 degrees, the ghost Occurrence is considered to be a problem in many cases.

2-2. Requirement (1) to Requirement (4) In such a case, the camera module 100 according to the present embodiment satisfies the following requirements (1) to (4), and thus an environment in which near-infrared light is strong. In the case where the incident angle of the external light is 5 degrees at the bottom angle and the incident angle is 30 degrees at a high angle, a high-quality image with less ghost can be captured.

The requirements (1) and (2) are as follows.
Requirements (1) R _NIR-5 <30
Requirement (2) R _NIR-30 <30
Here, R _NIR-5 is a value represented by the following equation.
RA5 (λ): The reflectance when the optical filter at a wavelength of λ nm is incident at 5 degrees from the optical lens group side.
RB5 (λ): The reflectance when the cover glass at a wavelength of λ nm is incident at 5 degrees from the optical lens group side.
Further, R _NIR-30 is a value represented by the following equation.
RA30 (λ): The reflectance when the optical filter at a wavelength of λ nm is incident at 30 degrees from the optical lens group side.
RB30 (λ): The reflectance when the cover glass at a wavelength of λ nm is incident at 30 degrees from the optical lens group side.

The requirements (3) and (4) are as follows.
Requirements (3) T _NIR-5 <30
Requirement (4) T _NIR-30 <30
Here, T _NIR-5 is a value represented by the following equation.
TA5 (λ): Transmittance when incident on an optical filter at a wavelength of λ nm at 5 degrees from the optical lens group side.
TB5 (λ): Transmittance when incident on the cover glass at a wavelength of λ nm from the side opposite to the optical lens group at 5 degrees.
Further, T _NIR-30 is a value represented by the following equation.
TA30 (λ): Transmittance when incident on an optical filter at a wavelength of λ nm at 30 degrees from the optical lens group side.
TB30 (λ): Transmittance when incident on the cover glass at a wavelength of λ nm from the side opposite to the optical lens group side at 30 degrees.

A method that satisfies the requirements (1) and (2), that is, both the reflectance of the light incident on the optical filter 111 from the optical lens group 104 and the reflectance of the light incident on the cover glass 109 from the optical lens group 104 are suppressed. Examples of the adjusting method include a method of providing a dielectric multilayer film having an antireflection effect at a wavelength of 700 nm to 1200 nm on one side or both sides of the optical filter 111.

By satisfying requirements (1) and (2), when a light source with strong near-infrared light is photographed, ghosts occur both at a low angle of incidence of 5 degrees and at a high angle of incidence of 30 degrees. It is possible to obtain a small number of high-quality camera images.

The method of satisfying the requirements (3) and (4), that is, the transmittance of the light incident on the optical filter 111 from the optical lens group 104 and the transmittance of the light incident on the cover glass 109 from the reflective surface of the optical lens group 104. As an adjustment method for suppressing both, for example, a method of providing a dielectric multilayer film for shielding near infrared rays having a wavelength of 700 nm to 1200 nm on the cover glass can be mentioned.

By satisfying requirements (3) and (4), in an environment with strong near-infrared light, both when the incident angle of external light is low at 0 degrees and when the incident angle is high at 30 degrees. It is possible to capture a high-quality image with few ghosts.

In the method of satisfying all the requirements (1) to (4), that is, in the optical characteristics of the optical filter 111 and the cover glass 109 incorporated in the camera module 100, the reflectance of the light incident on the optical filter 111 from the optical lens group 104 and the optics. The reflectance of light incident on the cover glass 109 from the lens group 104 is suppressed, and the transmittance of light incident on the optical filter 111 from the optical lens group 104 and the transmittance of light incident on the cover glass 109 from the optical lens group 104. As a method of suppressing the above, for example, an antireflection film (dielectric multilayer film) having an antireflection effect having a wavelength of 700 nm to 1200 nm is provided on one side (for example, the surface on the optical lens group 104 side) of the optical filter 111 or on both sides. Examples thereof include a method of providing a dielectric multilayer film that shields near infrared rays having a wavelength of 700 nm to 1200 nm on one side (the side on the optical lens group 104 side) of the cover glass 109 or on both sides.

By not providing a dielectric multilayer film that reflects near infrared rays having a wavelength of 700 nm to 1200 nm in both the optical filter 111 and the cover glass 109, ghosting is suppressed even if near infrared light enters the optical system of the camera module 100. can do. Since the near-infrared rays having a wavelength of 700 nm to 1200 nm transmitted through the optical filter 111 and the cover glass 109 are effectively shielded, flare generated by the influence of the near-infrared light can be suppressed.

In order to satisfy the requirements (1) to (4), for example, a dielectric multilayer film that shields near infrared rays at a wavelength of 700 nm to 1200 nm is provided on one side or both sides of the optical filter 111, and one side or both sides of the cover glass 109 is provided. A dielectric multilayer film having a wavelength of 700 nm to 1200 nm may be provided, but from the viewpoint that ghosts can be further reduced by reducing the reflected light of the optical filter 111 having a short distance from the image pickup element. , A dielectric multilayer film having an antireflection effect with a wavelength of 700 nm to 1200 nm is provided on one side or both sides of the optical filter 111, and a dielectric multilayer film that shields near infrared rays having a wavelength of 700 nm to 1200 nm on one side or both sides of the cover glass 109. May be provided.

2-2-1. Requirements (1)
In the region of wavelength 430 to 580 nm, the minimum value of the transmittance of light incident from the vertical direction of the optical filter T _b-0 and the minimum value of the transmittance of light incident from an oblique direction of 30 degrees with respect to the vertical direction T _{b- 30} is preferably 63% or more and 86% or less, and more preferably 67% or more and 82% or less. As a method of satisfying the requirement (1), that is, a method of adjusting the minimum value of each transmittance, for example, the type and the amount of the compound (A) to be added, which will be described later, are used so that the minimum value of the transmittance in the specified range can be obtained. Examples include a method of appropriately selecting and adjusting. By satisfying the requirement (1), the change in RGB balance (color balance) can be reduced even when the incident angle is as high as 30 degrees, and a high-quality image can be taken.

2-2-2. Requirement (2)
In the region of the wavelength 700～780Nm, the average value of the optical density for light incident from the mean _{OD a-0} and 30 ° oblique direction with respect to the vertical direction of the optical density for light incident from the vertical direction of the optical filter 111 OD _{a -30} is preferably 1.8 or more and 4.0 or less, more preferably 1.9 or more and 3.5 or less, and is an average value of optical densities OD _a for light incident from an oblique direction of 60 degrees with respect to the vertical direction. _-60 is preferably 2.1 or more and 4.5 or less, and more preferably 2.2 or more and 4.0 or less.

As a method of satisfying the requirement (2), that is, a method of adjusting the average value of the optical density (OD value), for example, the type of the compound (A) described later and the method of adjusting the average value of the transmittance in the specified range can be obtained. Examples thereof include a method of appropriately selecting and adjusting the addition amount.

By satisfying the requirement (2), the optical filter can sufficiently cut not only the near-infrared rays transmitted in the vertical direction but also the near-infrared rays transmitted at a high incident angle, so that there is no or reduced color shading. You can take an image.

Here, the OD value is a common logarithmic value of transmittance and can be calculated by the following equation (1). When the average OD value in the designated wavelength range is high, the optical filter 111 indicates that the light cut characteristic in the wavelength range is high.

2-2-3. Requirements (3)
In the region of the wavelength 900～1200Nm, average _{T IR} of the transmittance of light incident from the vertical direction of the optical filter is preferably from 70% to 98%, more preferably 80% to 95%, more preferably 85% It is 94%, particularly preferably 89% to 93%.

As a method of satisfying the requirement (3), that is, a method of adjusting the average value of the light transmittance, for example, the type and the amount of the compound (A) to be added, which will be described later, are appropriately selected so as to obtain the transmittance in the specified range. There is a method of adjustment.

By satisfying the requirement (3), the transmittance in the near-infrared region is high and the reflected light in the near-infrared region can be reduced, so that a camera image with reduced ghost can be obtained.

2-2-4. Requirements (4)
In the region of wavelength 430 to 580 nm, the average value Ta _-0 of the transmittance of light incident from the vertical direction of the optical filter is preferably 73% or more and 88% or less, more preferably 76% or more and 86% or less. The average value _Ta-30 of the transmittance of light incident from an oblique direction of 30 degrees with respect to the vertical direction is preferably 72% or more and 87% or less, more preferably 75% or more and 85% or less, with respect to the vertical direction. The average value _Ta-60 of the transmittance of light incident from an oblique direction of 60 degrees is preferably 68% or more and 85% or less, and more preferably 70% or more and 80% or less.

As a method of satisfying the requirement (4), that is, a method of adjusting the average value of each transmittance, for example, the type and the amount of the compound (A) to be added, which will be described later, are used so that the average value of the transmittance in the specified range can be obtained. Examples include a method of appropriately selecting and adjusting.

By satisfying the requirement (4), a high-quality camera image can be obtained because the change in RGB balance is small even when the incident angle is high such as 30 degrees or 60 degrees.

3. 3. Details of Near Infrared Light Reflector (Optical Filter) Details of the optical filter as a near infrared light absorber for satisfying the above requirements (1) to (4) will be described.

3-1. Thickness of Optical Filter The thickness of the optical filter 111 is preferably 210 μm or less, more preferably 190 μm or less, further preferably 160 μm or less, particularly preferably 130 μm or less, and the lower limit is not particularly limited, but is preferably 20 μm or more. ..

3-2. The configuration of the base material optical filter 111 is not particularly limited as long as the above-mentioned optical characteristics can be obtained, but it is preferable to include a base material satisfying the following requirement (a), and the base material further satisfies the following requirement (b). Is preferable.
Requirement (e) A layer containing the compound (A) having an absorption maximum in a region having a wavelength of 650 to 800 nm is provided.
Requirement (f) Wavelength X on the longest wavelength side in which the transmittance for light incident from the vertical direction of the substrate at a wavelength of 600 to 900 nm is more than 10% to 10% or less from the short wavelength side to the long wavelength side. difference between _a, transmittance of light incident from the vertical direction of the substrate, the wavelength X _b the most from the short wavelength side of 10% or less than 10% toward the long wavelength side shorter wavelength side | X _b -X _a | is 100 nm or more. Each requirement will be described below.

3-3. Requirements (e)
In the requirement (e), the components constituting the layer containing the compound (A) are not particularly limited, and examples thereof include transparent resins, sol-gel materials, low-temperature cured glass materials, etc., but they are easy to handle and the compounds ( From the viewpoint of compatibility with A), a transparent resin is preferable.

3-4. Compound (A)
The compound (A) is not particularly limited as long as it has an absorption maximum in the region of 650 to 800 nm, but is selected from the group consisting of a squarylium compound, a phthalocyanine compound, a naphthalocyanine compound, a croconium compound and a cyanine compound at least. It is preferably one kind of compound, and particularly preferably a squarylium compound, a phthalocyanine compound and a cyanine compound. The compound (A) may be used alone or in combination of two or more.

Squalylium-based compounds have excellent visible light transmittance, steep absorption characteristics, and a high molar extinction coefficient, but may generate fluorescence that causes scattered light when absorbing light. In such a case, by using the squarylium compound and the other compound (A) in combination, it is possible to obtain an optical filter 111 having less scattered light and better image quality.

The absorption maximum wavelength of compound (A) is preferably 660 nm or more and 795 nm or less, and more preferably 680 nm or more and 790 nm or less.

The compound (A) is not particularly limited as long as it has an absorption maximum in the wavelength region of 650 to 800 nm, but from the viewpoint of heat resistance of the optical filter, the compound (A) has an absorption maximum in the wavelength region of 650 nm or more and 715 nm or less, and has a wavelength of more than 715 nm. It is more preferable to contain at least one compound having an absorption maximum in the region of 750 nm or less and a compound having an absorption maximum in the region of more than 750 nm and 800 nm or less.

When the compound (A) is a combination of two or more kinds of compounds, the difference between the absorption maximum wavelengths of the compound (A) to be applied having the shortest absorption maximum wavelength and the longest absorption maximum wavelength is preferably 20 to 20 to. It is 100 nm, more preferably 30 to 90 nm, and even more preferably 40 to 80 nm. When the difference in absorption maximum wavelength is within the above range, scattered light due to fluorescence can be sufficiently reduced, and a wide absorption band around 700 nm and excellent visible light transmittance can be compatible with each other, which is preferable.

As for the content of the entire compound (A), for example, a base material made of a transparent resin substrate containing the compound (A) can be used as the base material. When a base material in which a resin layer such as an overcoat layer made of a curable resin or the like is laminated on a transparent resin substrate containing the compound (A) is used, the compound (A) is added to 100 parts by mass of the transparent resin. However, those containing 0.04 to 2.0 parts by mass, more preferably 0.06 to 1.5 parts by mass, and further preferably 0.08 to 1.0 parts by mass can be used. Further, when a base material in which a transparent resin layer such as an overcoat layer made of a curable resin containing the compound (A) is laminated on a support such as a glass support or a resin support as a base is used. The compound (A) is preferably 0.4 to 5.0 parts by mass, more preferably 0.6 to 4.0 parts by mass, and further preferably 0 with respect to 100 parts by mass of the resin forming the transparent resin layer. .8 to 3.5 parts by mass can be used.

3-4-1. Squalilium-based compounds Examples of the squalylium-based compounds include compounds represented by the following formula (A1).
In formula (A1), X independently represents a methylene group or an alkylene group having 2 to 12 carbon atoms in which one or more hydrogen atoms are substituted, and Z ⁶ , Z ⁷ , and Z ⁸ are independent of each other. , A hydrogen atom, an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent, and a substituent. Also shows a good heteroaromatic ring group with 5 to 20 carbon atoms.
Z ⁹ has an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, an aromatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, and a substituent. Also shows a good heterocyclic functional group having 5 to 20 carbon atoms.

Specific examples of such a formula (A1) include a compound of the formula (A1-1) represented by the following formula. The maximum absorption (λmax) of the compound of (A1-1) is 752 nm.

Further, as a squarylium-based compound different from the compound (A1), the compound shown by Mr. (A1-2) below can be mentioned.

Further, among the squarylium compounds, a compound represented by the formula (A2) can be mentioned as a compound having a maximum absorption on the longer wavelength side than the compound of the formula (A1).

In the formula (A2), Z ⁶ and Z ⁷ independently have a hydrogen atom and an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent and an aromatic which may have a substituent. It shows a heterocyclic functional group having 5 to 20 carbon atoms which may have a hydrocarbon group and a substituent.

Specific examples of such a formula (A2) include a compound of the formula (A2-1) represented by the following formula. The maximum absorption (λmax) of the compound of (A2-1) is 776 nm.

Moreover, as a phthalocyanine compound, a compound represented by the following formula (A3) can be mentioned.

In the formula (A3), Z ¹⁰ is independently a hydrogen atom, an aliphatic hydrocarbon having 1 to 12 carbon atoms which may have a substituent, and an aromatic having 6 to 12 carbon atoms which may have a substituent. It represents a heterocyclic functional group having 5 to 20 carbon atoms which may have a group hydrocarbon group or a substituent, and M represents metal-free, metal, or metal oxide. Examples of the metal include Zn, Mg, Si, Sn, Rh, Pt, Pd, Mo, Mn, Pb, Cu, Ni, Co, Fe and the like, and examples of the metal oxide include VO and TiO.

As a specific example of such a formula (A3), for example, it is a compound of (A3-1) represented by the following formula. The maximum absorption (λmax) of the compound of (A3-1) is 738 nm.

The cyanine compound is a dye containing only a compound having a structure in which an odd number of methine groups are conjugated and double-bonded between two heterocycles in the molecule as a dye. Specific examples of the cyanine compound include compounds represented by the following formulas (C1) and (C2).

In formula (C1), Z ¹ is an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent, an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent, and a substituent. It represents a heterocyclic functional group having 5 to 20 carbon atoms which may have a group, and Z ² may have a substituent and may have a substituent of 1 to 12 carbon atoms. It represents an aliphatic hydrocarbon group of 12, an aromatic hydrocarbon group having 6 to 12 carbon atoms which may have a substituent, and a heterocyclic functional group having 5 to 20 carbon atoms which may have a substituent. For example, one or more hydrogen atoms of a phenyl group and a naphthyl group may be substituted with a halogen or an alkyl group having 1 to 12 carbon atoms. In the formula (C2), Z ³ and Z ⁴ independently have a hydrogen atom and an aliphatic hydrocarbon group having 1 to 12 carbon atoms which may have a substituent and a substituent may have 6 carbon atoms. Shows are heterocyclic functional groups having 5 to 20 carbon atoms which may have from 12 aromatic hydrocarbon groups and substituents. n is an integer from 1 to 12. X indicates a counter anion.
The substituent in the compound (A) is a halogen, a hydroxyl group, an aldehyde group, an aliphatic hydrocarbon group having 1 to 12 carbon atoms, an aromatic hydrocarbon group having 1 to 12 carbon atoms, and an alkoxyl having 1 to 12 carbon atoms. A group, an acyl group having 1 to 12 carbon atoms, a ketone group, an alkoxycarbonyl group having 2 to 12 carbon atoms, an amine group, and an amine group in which one or more hydrogen atoms are substituted with an aliphatic hydrocarbon group having 1 to 12 carbon atoms. , Imine group, nitrile group, amide group, cyano group, thiol group, thioether group having a hydrocarbon group having 1 to 12 carbon atoms, dithiol group having a hydrocarbon group having 1 to 12 carbon atoms, 1 to 12 carbon atoms. Examples thereof include an alkylsulsulfonic group and a heterocycle having 4 to 20 carbon atoms.

Examples of the counter anion of X include halide ion, ClO ^4- , OH ⁻ , organic carboxylic acid anion, organic sulfonic acid anion, Lewis acid anion, organic metal complex anion, dye-derived anion, organic sulfonylimide acid anion, and organic sulfonylmethi. Dorate anion and the like can be mentioned. Examples of the halide ion include Cl ⁻ , Br ⁻ , I ^{− and the} like. Examples of the organic carboxylic acid anion include benzoate ion, alkanoate ion, trihaloalkanoate ion, nicotinate ion and the like. Examples of the organic sulfonic acid anion include benzenesulfonic acid ion, naphthalenesulfonic acid ion, p-toluenesulfonic acid ion, alcansulfonic acid ion and the like. Examples of the Lewis acid anion include hexafluorophosphate ion, tetrafluoroborate ion, hexafluoroantimonate ion, tetrakis (pentafluorophenyl) boron anion and the like.

Specific examples of such formulas (C1) and (C2) are, for example, the compounds of (C1-1) and (C2-1) represented by the following formulas. The maximum absorption (λmax) of the compound (C1-1) is 466 nm, and the maximum absorption (λmax) of the compound (C2-1) is 549 nm.

The base material may be a single layer or a multilayer as long as it has a layer containing the compound (A).

3-5. Thickness of Base Material The thickness of the base material can be appropriately selected depending on the desired application and is not particularly limited, but is preferably 10 to 200 μm, more preferably 20 to 180 μm, and further preferably 25 to 150 μm. When the thickness of the base material is within the range, the optical filter using the base material can be made thinner and lighter, and can be suitably used for various applications such as a solid-state image sensor. In particular, when a base material made of a transparent resin substrate is used for a lens unit such as a camera module, it is preferable because the lens unit can be reduced in height and weight.

3-6. Transparent resin The transparent resin is not particularly limited as long as it does not impair the effects of the present invention. For example, in order to ensure thermal stability and moldability into a film, the glass transition temperature (Tg) is preferably 110. Examples thereof include resins having a temperature of about 380 ° C., more preferably 110 to 370 ° C., and even more preferably 120 to 360 ° C. Further, since it is suitable for the reflow step, the glass transition temperature of the resin is preferably 140 ° C. or higher, and more preferably 230 ° C. or higher.

As the transparent resin, when a resin plate having a thickness of 0.1 mm made of the resin is formed, the total light transmittance (JIS K7105) of the resin plate is preferably 75 to 95%, more preferably 78 to 95. %, Especially preferably 80 to 95% of the resin can be used. If a resin having a total light transmittance in such a range is used, the obtained substrate exhibits good transparency as an optical film.

The polystyrene-equivalent weight average molecular weight (Mw) measured by gel permeation chromatography (GPC) of a transparent resin is usually 15,000 to 350,000, preferably 30,000 to 250,000, and is a number. The average molecular weight (Mn) is usually 10,000 to 150,000, preferably 20,000 to 100,000.

Examples of the transparent resin include cyclic polyolefin resin, aromatic polyether resin, polyimide resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, polyamide resin, aramid resin, polysulfone resin, and poly. Ethersalphon resin, polyparaphenylene resin, polyamideimide resin, polyethylene naphthalate resin, fluorinated aromatic polymer resin, (modified) acrylic resin, epoxy resin, silsesquioxane UV curable type By resin, maleimide-based resin, alicyclic epoxy thermocurable resin, polyetheretherketone-based resin, polyarylate-based resin, allyl ester-based curable resin, acrylic UV-curable resin, vinyl-based UV-curable resin, and solgel method. Examples thereof include a resin containing the formed silica as a main component. Of these, the use of cyclic polyolefin resin, aromatic polyether resin, fluorene polycarbonate resin, fluorene polyester resin, polycarbonate resin, and polyarylate resin is transparent (optical characteristics), heat resistance, and reflow resistance. It is preferable in that an optical filter having an excellent balance such as the above can be obtained. The transparent resin may be used alone or in combination of two or more.

3-6-1. Cyclic polyolefin resin The cyclic polyolefin resin is at least one single amount selected from the group consisting of a monomer represented by the following formula (X ₀ ) and a monomer represented by the following formula (Y ₀ ). A resin obtained from the body and a resin obtained by hydrogenating the resin are preferable.

Wherein _{^{(X 0), R X1 ~R}} X4 each independently represents an atom or a group selected from the following (i ') ~ (ix' ), k X, m X and ^{p X} are each independently 0 Or represents a positive integer.
(I') Hydrogen atom (ii') Halogen atom (iii') Trialkylsilyl group (iv') Substituent or unsubstituted carbon number 1 having a linking group containing an oxygen atom, a sulfur atom, a nitrogen atom or a silicon atom. Hydrocarbon group (v') substituted or unsubstituted hydrocarbon group (vi') polar group having 1 to 30 carbon atoms (excluding (iv')).
(Vii ^') and the ^{R X1} and ^{R X2} or ^{R X3} and ^{R X4,} another bond formed to alkylidene group (wherein, ^R X1 ^{to R X4} which is not involved in binding are each independently (i') ~ Represents an atom or group selected from (vi').)
(Viii ^{') R X1} and ^{R X2} or ^{R X3} and ^{R X4} and are mutually formed bonded to the monocyclic or polycyclic hydrocarbon ring or a heterocyclic ring (provided that not involved in binding ^R X1 ^{to R X4} Represents an atom or group independently selected from (i') to (vi').)
(Ix ') and R ^X2 and R ^X3 is a hydrocarbon ring or a heterocyclic ring monocyclic formed are bonded to each other (however, R ^X1 and R ^X4 which is not involved in binding, each independently (i') Represents an atom or group selected from ~ (vi').)

In formula (Y ₀ ), R ^y1 and R ^y2 each independently represent an atom or group selected from (i') to (vi'), or R ^y1 and R ^y2 are formed by being bonded to each other. Represents monocyclic or polycyclic alicyclic hydrocarbons, aromatic hydrocarbons or heterocycles, where ^ky and ^py each independently represent 0 or a positive integer.

3-6-2. Commercially available products Examples of commercially available transparent resin products include the following commercially available products. Examples of commercially available cyclic polyolefin resins include Arton manufactured by JSR Co., Ltd., Zeonoa manufactured by Zeon Corporation, APEL manufactured by Mitsui Chemicals Co., Ltd., and TOPAS manufactured by Polyplastics Co., Ltd.

3-7. Other pigments (X)
The base material may further contain another dye (X) that does not correspond to the compound (A).

The other dye (X) is not particularly limited as long as it is a dye having a maximum absorption wavelength in the region of less than 650 nm or a wavelength of more than 800 nm and 1250 nm or less, and is, for example, a squarylium compound, a phthalocyanine compound, a cyanine compound, or na. At least one compound selected from the group consisting of phthalocyanine compounds, croconium compounds, octaphyllin compounds, diimonium compounds, pyrolopyrrole compounds, borondipyrromethene (BODIPY) compounds, perylene compounds and metal dithiolate compounds. Can be mentioned. By using such a dye, it is possible to achieve absorption characteristics and excellent visible light transmittance in a wide range of near-infrared wavelength regions.

The absorption maximum wavelength of the other dye (X) is preferably 805 nm or more and 1200 nm or less, and more preferably 810 nm or more and 1150 nm or less. When the absorption maximum wavelength of the other dye (X) is in such a range, unnecessary near-infrared rays can be efficiently cut, and the dependence of the incident light on the incident angle can be reduced.

The content of the other dye (X) is preferably relative to 100 parts by mass of the transparent resin when a base material made of a transparent resin substrate containing the other dye (X) is used as the base material. Is 0.005 to 1.0 parts by mass, more preferably 0.01 to 0.9 parts by mass, and particularly preferably 0.02 to 0.8 parts by mass, and serves as a base material such as a glass support or a base. A base material in which a transparent resin layer such as an overcoat layer made of a curable resin containing another dye (X) or the like is laminated on a support such as a resin support, or a transparent resin containing the compound (A). When a base material in which a resin layer such as an overcoat layer made of a curable resin containing another dye (X) is laminated on the substrate is used, a transparent resin layer containing another dye (X) is used. It is preferably 0.05 to 4.0 parts by mass, more preferably 0.1 to 3.0 parts by mass, and particularly preferably 0.2 to 2.0 parts by mass with respect to 100 parts by mass of the resin to be formed.

3-8. Other Ingredients The base material may further contain an antioxidant, a near-ultraviolet absorber, a fluorescent quencher and the like as other ingredients as long as the effects of the present invention are not impaired. These other components may be used alone or in combination of two or more.

Examples of the near-ultraviolet absorber include azomethine-based compounds, indole-based compounds, benzotriazole-based compounds, and triazine-based compounds.

Examples of the antioxidant include 2,6-di-t-butyl-4-methylphenol, 2,2'-dioxy-3,3'-di-t-butyl-5,5'-dimethyldiphenylmethane, tetrakis [ Methylene-3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, tris (2,4-di-t-butylphenyl) phosphite and the like can be mentioned.

These other components may be mixed with a resin or the like when the base material is produced, or may be added when the resin is synthesized. The amount to be added is appropriately selected according to the desired characteristics, but is usually 0.01 to 5.0 parts by mass, preferably 0.05 to 2.0 parts by mass with respect to 100 parts by mass of the resin. It is a department.

3-9. Method for Producing Base Material When the base material is a base material containing a transparent resin substrate containing the compound (A), the transparent resin substrate can be formed, for example, by melt molding or cast molding, and further. If necessary, a base material having an overcoat layer laminated can be produced by coating a coating agent such as an antireflection agent, a hard coating agent and / or an antistatic agent after molding.

An overcoat layer in which the base material is a curable resin containing the compound (A) on a support such as a glass support or a resin support as a base or a transparent resin substrate containing no compound (A). In the case of a base material on which a transparent resin layer such as is laminated, for example, a resin solution containing the compound (A) is melt-molded or cast-molded on a support or a transparent resin substrate, preferably spin-coated or slit. After coating by a method such as coating or inkjet, the solvent is dried and removed, and if necessary, further light irradiation or heating is performed to obtain a transparent resin layer containing the compound (A) on the support or the transparent resin substrate. Can be produced as a base material on which is formed.

3-9-1. Melt molding The melt molding is specifically a method of melt-molding a pellet obtained by melt-kneading a resin, a compound (A) and, if necessary, other components; a resin and a compound (A). A method of melt-molding a resin composition containing other components as needed; or obtained by removing the solvent from the compound (A), a resin, a solvent and a resin composition containing other components as needed. Examples thereof include a method of melt-molding the pellets. Examples of the melt molding method include injection molding, melt extrusion molding, blow molding and the like.

3-9-2. Cast molding In cast molding, a resin composition containing a compound (A), a resin, a solvent and, if necessary, other components is cast on a suitable support to remove the solvent; or the compound (A). A curable composition containing a photocurable resin and / or a thermosetting resin and, if necessary, other components is cast on a suitable support to remove the solvent, and then irradiated with ultraviolet rays or heated. It can also be manufactured by a method of curing by an appropriate method such as.

When the base material is a base material made of a transparent resin substrate containing the compound (A), the base material can be obtained by peeling the coating film from the support after cast molding. , The base material is an overcoat made of a curable resin containing the compound (A) or the like on a support such as a glass support or a resin support as a base or a transparent resin substrate containing no compound (A). In the case of a base material on which a transparent resin layer such as a layer is laminated, the base material can be obtained by not peeling off the coating film after cast molding.

As the support, for example, a phosphate-based material containing a copper component such as a near-infrared absorbing glass plate (for example, "BS1-13" manufactured by Matsunami Glass Industry Co., Ltd. or "NF-50T" manufactured by AGC Techno Glass Co., Ltd. Glass plate), transparent glass plate (for example, non-alkali glass plate such as "OA-10G" manufactured by Nippon Electric Glass Co., Ltd. and "AN100" manufactured by Asahi Glass Co., Ltd., crown glass plate such as "BK7" and "D263Teco" manufactured by SCHOTT. ), Steel belts, steel drums and supports made of transparent resin (for example, polyester film, cyclic olefin resin film).

Further, the optical component made of glass plate, quartz, transparent plastic, or the like is coated with a resin composition to dry the solvent, or a curable composition is coated to cure and dry the optical component. A transparent resin layer can also be formed on the surface.

The amount of residual solvent in the transparent resin layer (transparent resin substrate) obtained by the method should be as small as possible. Specifically, the amount of residual solvent is preferably 3% by weight or less, more preferably 1% by weight or less, still more preferably 0.5% by weight or less, based on the weight of the transparent resin layer (transparent resin substrate). Is. When the amount of the residual solvent is within the range, a transparent resin layer (transparent resin substrate) that is less likely to be deformed or changes in characteristics and can easily exhibit a desired function can be obtained.

3-10. Dielectric multilayer film (antireflection film for visible light)
The optical filter of the present invention preferably has a dielectric multilayer film having an antireflection effect. A dielectric multilayer film that reflects near infrared rays may be provided on at least one surface of the cover glass as long as the effects of the present invention are not impaired. The dielectric multilayer film of the optical filter in the present invention is a film having an antireflection effect in the visible region.

The dielectric multilayer film preferably has antireflection properties over a wavelength range of 400 to 800 nm, more preferably wavelengths of 410 to 750 nm, and even more preferably 420 to 700 nm.

As a form having dielectric multilayer films on both sides of the base material, when measured from the vertical direction of the optical filter, a form having dielectric multilayer films having antireflection characteristics mainly at a wavelength of around 400 to 800 nm on both sides of the base material. And so on.

The thickness of the dielectric multilayer film having an antireflection effect in the visible region is not particularly limited as long as the effect of the present invention is not impaired, but is preferably 0.01 to 1.0 μm, more preferably 0.05 to 0.5 μm. is there. By setting the thickness in the above range, an optical filter with less warpage and distortion can be obtained.

Examples of the dielectric multilayer film include those in which high refractive index material layers and low refractive index material layers are alternately laminated. As a material constituting the high refractive index material layer, a material having a refractive index of 1.7 or more can be used, and a material having a refractive index of 1.7 to 2.5 is usually selected. Examples of such a material include titanium oxide, zirconium oxide, tantalum pentoxide, niobium pentoxide, lanthanum oxide, yttrium oxide, zinc oxide, zinc sulfide, indium oxide and the like as main components, and titanium oxide, tin oxide and /. Alternatively, those containing a small amount of cerium oxide or the like (for example, 0 to 10% by weight based on the main component) can be mentioned.

As the material constituting the low refractive index material layer, a material having a refractive index of less than 1.7 can be used, and a material having a refractive index of usually 1.2 to less than 1.7 is selected. Examples of such a material include silica, alumina, lanthanum fluoride, magnesium fluoride and sodium hexafluoride, and a mixture thereof.

The method of laminating the high refractive index material layer and the low refractive index material layer is not particularly limited as long as a dielectric multilayer film in which these material layers are laminated is formed. For example, a dielectric in which high refractive index material layers and low refractive index material layers are alternately laminated directly on a base material by a CVD method, a sputtering method, a vacuum vapor deposition method, an ion-assisted vapor deposition method, an ion plating method, or the like. A multilayer film can be formed.

The thickness of each layer of the high refractive index material layer and the low refractive index material layer is usually preferably 0.1λ to 0.5λ, where λ (nm) is the near-infrared wavelength to be blocked. The value of λ (nm) is, for example, 700 to 1400 nm, preferably 750 to 1300 nm. When the thickness is in this range, the optical film thickness in which the product (n × d) of the refractive index (n) and the film thickness (d) is calculated by λ / 4, the high refractive index material layer, and the low refraction The thickness of each layer of the index material layer becomes almost the same value, and there is a tendency that the blocking / transmitting of a specific wavelength can be easily controlled due to the relationship between the optical characteristics of reflection / refraction.

The total number of layers of the high-refractive index material layer and the low-refractive index material layer in the dielectric multilayer film of the optical filter is preferably 1 to 20 layers as a whole, and preferably 2 to 12 layers. More preferred. By setting the number of layers in the above range, an optical filter with less warpage and distortion can be obtained.

In one embodiment of the present invention, the material species, the high refractive index material layer and the material species constituting the high refractive index material layer and the low refractive index material layer according to the absorption characteristics of the compound (A) and other dyes (X). By appropriately selecting the thickness of each layer of the low refractive index material layer, the order of lamination, and the number of laminations, it has sufficient light-cutting characteristics in the near-infrared wavelength region while ensuring sufficient transmittance in the visible region. Moreover, it is possible to reduce the refractive index when near infrared rays are incident from an oblique direction.

3-11. Antireflection layer The antireflection layer according to the first embodiment of the present invention has an effect of reducing the reflectance of a base material alone in light rays at a specific wavelength. Specifically, it represents a layer having an effect of having a reflectance of 4% or less in light having a wavelength having an antireflection effect and being incident from a direction perpendicular to the incident surface. The antireflection layer includes a dielectric single layer film having a refractive index lower than that of the base material, a dielectric multilayer film, and a conical or polygonal pyramid structure having a height or width or depth less than the wavelength of the light for antireflection. So-called moss eye).

3-12. Other Functional Films The optical filter according to an embodiment of the present invention is a dielectric material of a base material on at least one surface of the base material, between the base material and the dielectric multilayer film, as long as the effects of the present invention are not impaired. On the surface opposite to the surface on which the multilayer film is provided, or on the surface opposite to the surface on which the substrate of the dielectric multilayer film is provided, the surface hardness of the substrate and the dielectric multilayer film is improved, and chemical resistance is improved. Functional films such as an antireflection film, a hard coat film, and an antistatic film can be appropriately provided for the purpose of improvement, antistatic, and scratch erasing.

The optical filter according to the first embodiment of the present invention may include one layer made of a functional film or two or more layers. When the optical filter of the present invention contains two or more layers made of a functional film, it may contain two or more similar layers or two or more different layers.

The method of laminating the functional film is not particularly limited, but a coating agent such as an antireflection agent, a hard coating agent and / or an antistatic agent is melt-molded or cast-molded on the base material or the dielectric multilayer film in the same manner. The method of doing this can be mentioned.

It can also be produced by applying a curable composition containing a coating agent or the like on a base material or a dielectric multilayer film with a bar coater or the like, and then curing the composition by irradiation with ultraviolet rays or the like.

Examples of the coating agent include ultraviolet (UV) / electron beam (EB) curable resin and thermosetting resin. Specific examples thereof include vinyl compounds, urethane-based, urethane acrylate-based, acrylate-based, and epoxy-based coating agents. And epoxy acrylate resin and the like. Examples of the curable composition containing these coating agents include vinyl-based, urethane-based, urethane acrylate-based, acrylate-based, epoxy-based and epoxy acrylate-based curable compositions.

Further, the curable composition may contain a polymerization initiator. As the polymerization initiator, a known photopolymerization initiator or thermal polymerization initiator can be used, and the photopolymerization initiator and the thermal polymerization initiator may be used in combination. The polymerization initiator may be used alone or in combination of two or more.

The proportion of the polymerization initiator in the curable composition is preferably 0.1 to 10% by weight, more preferably 0.5 to 10% by weight, and further, when the total amount of the curable composition is 100% by weight. It is preferably 1 to 5% by weight. When the blending ratio of the polymerization initiator is within the range, it is possible to obtain a functional film such as an antireflection film, a hard coat film or an antistatic film which has excellent curing properties and handleability of the curable composition and has a desired hardness. ..

Further, an organic solvent may be added to the curable composition as a solvent, and known organic solvents can be used. Specific examples of the organic solvent include alcohols such as methanol, ethanol, isopropanol, butanol and octanol; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; ethyl acetate, butyl acetate, ethyl lactate, γ-butyrolactone and propylene. Esters such as glycol monomethyl ether acetate and propylene glycol monoethyl ether acetate; ethers such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; aromatic hydrocarbons such as benzene, toluene and xylene; dimethylformamide, dimethylacetamide, N- Examples thereof include amides such as methylpyrrolidone. The solvent may be used alone or in combination of two or more.

The thickness of the functional film is preferably 0.1 to 20 μm, more preferably 0.5 to 10 μm, and particularly preferably 0.7 to 5 μm.

Further, for the purpose of improving the adhesion between the base material and the functional film and / or the dielectric multilayer film and the adhesion between the functional film and the dielectric multilayer film, a corona is formed on the surface of the base material, the functional film or the dielectric multilayer film. Surface treatment such as treatment or plasma treatment may be performed.

4. Optical lens group The camera module according to the embodiment of the present invention has 12 or less optical lens groups. As a material constituting the optical lens group, a transparent resin, glass, a metal oxide, and a metal nitride are preferable. From the viewpoint of suppressing ghosts due to reflected light between optical lens groups, 6 or more to 11 or less are more preferable. When the focus of light is bound to the sensor with an optical lens group having a curvature made of transparent resin or glass, it is preferable that the lens surface of the optical lens group has an antireflection film. As the optical lens group, a metal lens having a structure of a metal oxide having a size of less than 1 μm may be used, and it is more preferable to use a metal lens because the resulting image pickup apparatus can have a lower profile. The CRA of the optical lens group is preferably 30 degrees or more and 60 degrees or less. If it is less than 30 degrees, the viewing angle of the image obtained is narrow with respect to the viewing angle of a human being, and the scenes that can be photographed are limited. When the temperature is 60 degrees or more, the amount of light in the vicinity of the edge of the sensor pixel is greatly reduced, and it becomes difficult to maintain the contrast by placing it in both the center of the image and the peripheral portion of the image.

The camera module according to the embodiment of the present invention is between optical lens groups as shown in FIG. 2B or as shown in FIG. 2C from the viewpoint of suppressing ghosts caused by stray light incident at a very high angle. It is provided on the sensor side at the bottom of the optical lens group. It is more preferable that the optical filter is provided between the optical lens groups as shown in FIG. 2B from the viewpoint that the distance between the sensor and the optical filter can be increased and ghosting can be further suppressed.

5. Applications of the camera module The camera module according to the embodiment of the present invention can obtain an image having a wide viewing angle and less flare, color shading, and ghosting. Therefore, in particular, camera modules, digital still cameras, smartphone cameras, mobile phone cameras, digital video cameras, wearable device cameras, PC cameras, surveillance cameras, automobile cameras, televisions, car navigation systems, mobile information terminals, video games. It is useful for machines, portable game machines, retinal authentication systems, eyeball authentication systems, vein authentication systems, fingerprint authentication systems, digital music players, and the like. Here, the camera module is a module equipped with a solid-state image sensor such as a CCD or a CMOS image sensor, and specifically, a digital still camera, a smartphone camera, a mobile phone camera, a wearable device camera, or a digital video camera. It can be used for such purposes. For example, the camera module according to an embodiment of the present invention includes an optical filter 111. Here, the camera module is a device including an image sensor, a focus adjustment mechanism, a phase detection mechanism, a distance measurement mechanism, and the like, and outputs an image or distance information as an electric signal.

Further, the electronic device according to the embodiment of the present invention has the camera module of the present invention. The electronic device is not particularly limited, and examples thereof include smartphones, mobile phones, and PCs in the above-mentioned applications.

6. Each physical property value Hereinafter, the present invention will be described in more detail based on Examples, but the present invention is not limited to these Examples. In addition, "part" means "mass part" unless otherwise specified. The method for measuring each physical property value and the method for evaluating the physical property are as follows.

6-1. Molecular Weight The molecular weight of the resin was measured by the following method (a) or (b) in consideration of the solubility of each resin in a solvent and the like.
(A) Using a gel permeation chromatography (GPC) apparatus (150C type, column: H type column manufactured by Tosoh Corporation, developing solvent: o-dichlorobenzene) manufactured by WATERS, weight average molecular weight in terms of standard polystyrene. (Mw) and number average molecular weight (Mn) were measured.
(B) Using a GPC apparatus manufactured by Tosoh Corporation (HLC-8220 type, column: TSKgelα-M, developing solvent: THF), the weight average molecular weight (Mw) and the number average molecular weight (Mn) in terms of standard polystyrene were measured.
For the resin synthesized in Resin Synthesis Example 3 described later, the logarithmic viscosity was measured by the following method (c) instead of the molecular weight measurement by the above method.

6-2. Glass transition temperature (Tg)
Using a differential scanning calorimeter (DSC6200) manufactured by SII Nano Technologies Co., Ltd., the temperature was measured at a heating rate of 20 ° C. per minute under a nitrogen stream.

6-3. Spectral Transmittance The transmittance of the base material and the optical filter at each wavelength was measured using a spectrophotometer (U-4100) manufactured by Hitachi High-Technologies Corporation.

Here, in the transmittance measured from the vertical direction of the optical filter, the light 1 transmitted perpendicularly to the optical filter 2 is measured by the spectrophotometer 3 as shown in FIG. 1A, and the optical filter is vertical. As for the transmittance when measured from an angle of 30 degrees with respect to the direction, as shown in FIG. 1 (B), the light 1'transmitted at an angle of 30 degrees with respect to the vertical direction of the optical filter 2 is transmitted by the spectrophotometer 3. When the transmittance is measured and measured from an angle of 60 degrees with respect to the vertical direction of the optical filter, the light 1 transmitted at an angle of 60 degrees with respect to the vertical direction of the optical filter 2 as shown in FIG. 1 (C). '' Was measured with a spectrophotometer 3.

7. Evaluation of camera image Color shading evaluation, flare evaluation, and ghost evaluation were performed as evaluation items of the camera image. The contents of each item are shown below.

7-1. Color shading evaluation of camera image The color shading evaluation when the optical filter was incorporated into the camera module was performed by the following method. A camera module as shown in FIG. 2 was produced in the same manner as in JP-A-2016-110067, and a white plate having a size of 300 mm × 400 mm (Labsphere, Inc. Spectralon standard reflection) was produced using the obtained camera module. The target CSRT-99-180 cut out to the above size) was photographed under a D65 light source (X-Rite standard light source device “Macbeth Judge II”). The difference in color between the central portion (position of 150 mm in the vertical direction and 200 mm in the horizontal direction) and the end portion (position of 280 mm in the vertical direction and 380 mm in the horizontal direction) of the white plate in the camera image was evaluated according to the following criteria.

There is no problem at all and the acceptable level is A, a slight difference in color is recognized, but there is no problem in practical use as a high-quality camera module, and the acceptable level is B. The possible level was determined to be C, and the level that was unacceptable for general camera module applications due to a clear difference in color was determined to be D.

As shown in FIG. 4, when taking a picture, the positional relationship between the white plate 202 and the camera module was adjusted so that the white plate 202 occupies 90% or more of the area in the camera image 200. Further, as the cover glass 109x in FIG. 2, a cover glass having the film structure shown in Table 1 below was used, and as the optical filter 111x, the optical filters prepared in the following Examples and Comparative Examples were used.

7-2. Flare evaluation of camera image Flare evaluation when the optical filter was incorporated into the camera module was performed by the following method. A camera module as shown in FIG. 2 was produced in the same manner as in JP-A-2016-110067. As the cover glass 109x in FIG. 2, the cover glass 1 having the film structure shown in Table 1 was used, and as the optical filter 111x, the optical filters prepared in the following Examples and Comparative Examples were used.

Using the manufactured camera module, a photograph was taken in a dark room under a halogen lamp light source (“Luminer Ace LA-150TX” manufactured by Hayashi Clock Industry Co., Ltd.), and the degree of flare generation around the light source in the camera image was evaluated according to the following criteria.

There is no problem at all and the acceptable level is A, some flare is recognized, but there is no practical problem as a high-quality camera module and the acceptable level is B, flare occurs and it is unacceptable for high-quality camera module applications. The possible level was determined to be C, and the level that was unacceptable for general camera module applications with a severe degree of flare was determined to be D.

As shown in FIG. 5, when taking a picture, the halogen lamp light source was arranged at a distance of 1 mm from the camera module and adjusted so as to be in the center of the camera image 208. The ISO sensitivity was set to 100, and the focus was adjusted to the position of the light source. In the obtained image, the flare inside the circle having the same center as the light source and having a radius twice the radius of the light source and outside the circle of the light source was evaluated as the flare 212 around the light source.

7-3. Ghost evaluation of camera image The ghost evaluation when the optical filter was incorporated into the camera module was performed by the following method. A camera module is manufactured by the same method as the flare evaluation of the camera image, and the camera module is photographed under a halogen lamp light source in a dark room (“Luminer Ace LA-150TX” manufactured by Hayashi Clock Industry Co., Ltd.) in the camera image. The degree of ghost generation around the light source was evaluated according to the following criteria.

There is no problem at all and the acceptable level is A, some ghosts are recognized, but there is no practical problem as a high-quality camera module and the acceptable level is B, ghosts are generated and it is unacceptable for high-quality camera module applications. The possible level was determined to be C, and the level that was unacceptable for general camera module applications with a severe degree of ghost was determined to be D.

As shown in FIG. 6, when shooting, the halogen lamp light source 216 is arranged at a distance of 1 mm from the camera module, and the upper right end portion of the camera image 214 (the same position as the end portion of the color shading evaluation of the camera image). ) Was adjusted. The ghost generated at the position closest to the light source was defined as the ghost 218 around the light source.

8. Synthesis Example The compound (A) and the near-infrared absorbing dye (X) used in the following examples were synthesized by a generally known method. As a general synthesis method, for example, JP-A-60-228448, JP-A-1-146846, JP-A-1-228960, Patent No. 4081149, JP-A-63-124054, " Phthalocyanine-Chemistry and Function- "(IPC, 1997), JP-A-2007-169315, JP-A-2009-108267, JP-A-2010-241873, and the like. ..

8-1. Resin synthesis example 1
8-Methyl-8-methoxycarbonyltetracyclo represented by the following formula (a) [4.4.0.1 ^2,5 . ^{17 and 10} ] 100 parts of dodeca-3-ene (hereinafter also referred to as "DNM"), 18 parts of 1-hexene (molecular weight regulator) and 300 parts of toluene (solvent for ring-opening polymerization reaction) are replaced with nitrogen. It was placed in a container and the solution was heated to 80 ° C. Next, 0.2 parts of a toluene solution of triethylaluminum (0.6 mol / liter) and a toluene solution of methanol-modified tungsten hexachloride (concentration 0.025 mol / liter) were added to the solution in the reaction vessel as a polymerization catalyst. Nine parts were added, and the solution was heated and stirred at 80 ° C. for 3 hours to cause a ring-opening polymerization reaction to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%.

1,000 parts of the ring-opening polymer solution thus obtained was charged into an autoclave, and 0.12 parts of RuHCl (CO) [P (C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opening polymer solution. Then, under the conditions of a hydrogen gas pressure of 100 kg / cm ² and a reaction temperature of 165 ° C., the hydrogenation reaction was carried out by heating and stirring for 3 hours. After cooling the obtained reaction solution (hydrogenated polymer solution), hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover the coagulated product, which was dried to obtain a hydrogenated polymer (hereinafter, also referred to as "resin A"). The obtained resin A had a number average molecular weight (Mn) of 32,000, a weight average molecular weight (Mw) of 137,000, and a glass transition temperature (Tg) of 165 ° C.

[Example 1]
In a container, 100 parts of the resin A obtained in Resin Synthesis Example 1, 0.05 part of the compound represented by the following formula (A1-1) (absorption maximum wavelength in dichloromethane, 712 nm), and the following formula (A3-1). Add 0.12 parts of the compound represented (absorption maximum wavelength 738 nm in dichloromethane), 0.05 part of the compound represented by the following formula (A2-1) (absorption maximum wavelength 776 nm in dichloromethane), and methylene chloride. A solution having a resin concentration of 20% by weight was prepared. The obtained solution was cast on a smooth glass plate, dried at 20 ° C. for 8 hours, and then peeled off from the glass plate. The peeled coating film was further dried under reduced pressure at 100 ° C. for 8 hours to obtain a substrate made of a transparent resin substrate having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm.

A silica (SiO ₂ ) layer having a film thickness of 10 nm to 132 nm and a titania (TiO ₂ ) layer having a film thickness of 21 nm to 110 nm are formed on both sides of the substrate as a dielectric multilayer film (I) by ion-assisted deposition at a vapor deposition temperature of 120 ° C. And were laminated alternately (8 layers in total). The silica layer and the titania layer of the dielectric multilayer film (I) were alternately laminated in the order of the titania layer, the silica layer, the titania layer, and the silica layer from the base material side, and the outermost layer of the optical filter was a silica layer. The membrane composition is shown in Table 2 below.

The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter made of this base material. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 7 and Table 4.

[Example 2]
In Example 1, 0.03 part of the compound represented by the following formula (A1-2) (absorption maximum wavelength in dichloromethane 686 nm), 0.04 part of the compound represented by the formula (A2-1) and the following formula ( A transparent resin substrate was obtained under the same procedure and conditions as in Example 1 except that 0.06 part of the compound represented by C2-2) (absorption maximum wavelength in dichloromethane, 760 nm) was used.

The resin composition (1) having the following composition was applied to one side of the obtained transparent resin substrate with a bar coater, and heated in an oven at 70 ° C. for 2 minutes to volatilize and remove the solvent. At this time, the coating conditions of the bar coater were adjusted so that the thickness after drying was 2 μm. Next, exposure (exposure amount: 500 mJ / cm ² , 200 mW) was performed using a conveyor type exposure machine to cure the resin composition (1), and a resin layer was formed on the transparent resin substrate. Similarly, a resin layer made of the resin composition (1) was formed on the other surface of the transparent resin substrate to obtain a substrate having resin layers on both sides of the transparent resin substrate. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. In addition, a camera module was produced using the obtained optical filter, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 8 and Table 4.

Resin composition (1): tricyclodecanedimethanol diacrylate 60 parts, dipentaerythritol hexaacrylate 40 parts, 1-hydroxycyclohexylphenyl ketone 5 parts, methyl ethyl ketone (solvent, solid content concentration (TSC): 30%)

[Example 3]
In Example 1, 0.04 parts of (A1-1) compound, 0.03 part of (A1-2) compound, 0.10 part of (A3-1) compound, and 0.04 part of (A2-1) compound and A base material made of a transparent resin substrate was obtained under the same procedure and conditions as in Example 1 except that 0.05 part of the compound (C2-2) was used. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 9 and Table 4.

[Example 4]
In Example 1, 0.04 part of the (A1-1) compound and 0.03 part of the (A1-2) compound were used, 0.01 part of the (A3-1) compound was used, and (A2-1). 0.03 part of compound and 0.04 part of (C2-2) compound were used, and near-infrared absorption dye (XA) represented by the following formula (XA) (absorption maximum wavelength 813 nm in dichloromethane) 0. A base material made of a transparent resin substrate containing the compound (A) and the near-infrared absorbing dye (X) was obtained under the same procedure and conditions as in Example 1 except that 0.04 part was used. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 10 and Table 4.

[Example 5]
In a container, 100 parts by mass of the resin A obtained in Resin Synthesis Example 1, 0.30 parts of the (A1-1) compound, 0.10 parts of the (A1-2) compound, 0.70 part of the (A3-1) compound, (A2-1) 0.40 part of the compound and methylene chloride were added to prepare a solution (A1) having a resin concentration of 20% by weight. A resin composition (2) having the following composition is applied with a spin coater on a transparent glass substrate "OA-10G (thickness 150 μm)" (manufactured by Nippon Electric Glass Co., Ltd.) cut into a size of 60 mm in length and 60 mm in width. The solvent was volatilized and removed by heating on a hot plate at 80 ° C. for 2 minutes. At this time, the coating conditions of the spin coater were adjusted so that the thickness after drying was 0.8 μm. Next, the solution (A1) was applied onto the resin layer using an applicator under conditions such that the film thickness after drying was 20 μm, and heated on a hot plate at 80 ° C. for 5 minutes to volatilize and remove the solvent. A transparent resin layer was formed. Next, the glass surface was exposed from the glass surface side using a conveyor type exposure machine (exposure amount 1 J / cm ² , illuminance 200 mW), and then fired in an oven at 180 ° C. for 5 minutes to obtain a substrate.

Next, exposure (exposure amount: 500 mJ / cm ² , 200 mW) was performed using a conveyor type exposure machine to cure the resin composition (2), and a substrate made of a transparent glass substrate having a transparent resin layer was obtained. .. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The spectral transmittance of this optical filter was measured to evaluate the optical characteristics. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2C was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 11 and Table 4.

Resin composition (2): Isocyanurate ethylene oxide-modified triacrylate (trade name: Aronix M-315, manufactured by Toa Synthetic Chemical Co., Ltd.) 30 parts, 1,9-nonanediol diacrylate 20 parts, methacrylic acid 20 parts, 30 parts of glycidyl methacrylate, 5 parts of 3-glycidoxypropyltrimethoxysilane, 5 parts of 1-hydroxycyclohexylbenzophenone (trade name: IRGACURE184, manufactured by Ciba Specialty Chemical Co., Ltd.) and Sun Aid SI-110 main agent (Sanshin) A solution obtained by mixing 1 part (manufactured by Kagaku Kogyo Co., Ltd.), dissolving it in propylene glycol monomethyl ether acetate so that the solid content concentration becomes 50 wt%, and then filtering it with a millipore filter having a pore size of 0.2 μm.

[Example 6]
In Example 1, 0.04 part of (A1-1) compound and 0.03 part of (A1-2) compound were used, 0.34 part of (A3-1) compound was used, and (A2-1). ) A substrate made of a transparent resin substrate was obtained under the same procedure and conditions as in Example 1 except that 0.04 part of the compound was used and the thickness of the transparent resin substrate was 0.08 mm. It was. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 12 and Table 4.

[Example 7]
In Example 1, 0.05 part of the (A1-1) compound was used, 0.85 part of the (A3-1) compound was used, and 0.05 part of the (A2-1) compound was used. A substrate made of a transparent resin substrate was obtained under the same procedure and conditions as in Example 1 except that the thickness of the transparent resin substrate was 0.04 mm. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 13 and Table 4.

[Example 8]
A resin having a resin concentration of 20% by weight was prepared by adding the resin A and methylene chloride obtained in Resin Synthesis Example 1 to a container, and the obtained solution was used in the same manner as in Example 1. A plastic support was prepared.

A resin layer made of the resin composition (3) having the following composition is applied to one side of the obtained resin support with an applicator so that the thickness of the resin layer after drying is 4 μm, and dried at 20 ° C. for 8 hours. Then, it was further dried under reduced pressure at 100 ° C. for 8 hours to obtain a substrate having a transparent resin layer containing the compound (A) and the near-infrared absorbing dye (X) on one side of the resin support. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 14 and Table 4.

Resin composition (3): 100 parts by mass of the resin A obtained in Resin Synthesis Example 1, 0.50 parts of the (A1-1) compound, 0.50 parts of the (A2-1) compound, and (C2-2) compound 2. .50 parts, near infrared absorbing dye (X) 1.40 parts, methylene chloride (solvent, TSC: 25%)

[Example 9]
The resin composition (2) was applied with a spin coater on a near-infrared absorbing glass substrate "BS11 (manufactured by Matsunami Glass Industry Co., Ltd.) polished to a thickness of 120 μm" cut to a size of 60 mm in length and 60 mm in width. The solvent was volatilized and removed by heating on a hot plate at 80 ° C. for 2 minutes. At this time, the coating conditions of the spin coater were adjusted so that the thickness after drying was 0.8 μm. Next, the resin layer composed of the resin composition (4) having the following composition is applied with an applicator so that the thickness of the resin layer after drying is 4 μm, and then exposed using a conveyor type exposure machine (exposure amount: The resin composition (2) was cured by performing 500 mJ / cm ² , 200 mW) to obtain a substrate made of a near-infrared absorbing glass substrate having a transparent resin layer containing the compound (A). A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in Table 4.

Resin composition (4): 100 parts by mass of the resin A obtained in Resin Synthesis Example 1, 1.00 parts of the (A1-1) compound, 1.00 parts of the (A2-1) compound, and 5 parts of the (C2-2) compound. .00 parts, methylene chloride (solvent, TSC: 25%)

[Example 10]
In Example 1, 0.04 part of the (A1-1) compound and 0.03 part of the (A1-2) compound were used, 0.14 part of the (A3-1) compound was used, and (A2-1). ) Compound (A) and near-red under the same procedure and conditions as in Example 1 except that 0.04 part of compound was used and 0.04 part of near-infrared absorbing dye (X) was used. A substrate made of a transparent resin substrate containing an external absorption dye (X) was obtained. A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. In addition, a camera module was produced using the obtained optical filter, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 15 and Table 4.

[Example 11]
In Example 1, 0.04 part of (A1-1) compound and 0.03 part of (A1-2) compound were used, 0.34 part of (A3-1) compound was used, and (A2-). 1) A substrate made of a transparent resin substrate was obtained under the same procedure and conditions as in Example 1 except that 0.04 part of the compound was used.

A dielectric multilayer film (I) was provided on both sides of the obtained base material in the same manner as in Example 1 to obtain an optical filter. The optical characteristics were evaluated by measuring the spectral transmittance of the optical filter. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 16 and Table 4.

[Comparative Example 1]
Transparent under the same procedure and conditions as in Example 1 except that 0.07 part of (A1-1) compound was used and 0.08 part of (A3-1) compound was used in Example 1. A substrate made of a resin substrate was obtained. The | X _b- X _a | of the obtained substrate was 61 nm, which was less than 100 nm.

Subsequently, a silica (SiO ₂ ) layer and a titania (TiO ₂ ) layer are alternately laminated as a dielectric multilayer film (II) on one surface of the obtained base material (26 layers in total). II) is formed, and silica (SiO ₂ ) layers and titania (TiO ₂ ) layers are alternately laminated as a dielectric multilayer film (III) on the other surface of the base material (20 layers in total). A body multilayer film (III) was formed to obtain an optical filter having a thickness of about 0.105 mm. The dielectric multilayer film (II) and the dielectric multilayer film (III) are as shown in Table 3 below.

The spectral transmittance of the obtained optical filter was measured to evaluate the optical characteristics. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 17 and Table 4. Although the optical filter obtained in Comparative Example 1 exhibits relatively good optical density and shielding performance of 700 nm to 1200 nm, it is considered to be due to near-infrared reflection by the dielectric multilayer film of the optical filter and reflection of the cover glass. Occurrence of ghost was confirmed.

[Comparative Example 2]
From the transparent resin substrate, except that 0.07 part of (A1-1) compound was used and 0.08 part of (A3-1) compound was used under the same procedure and conditions as in Comparative Example 1. A base material was obtained. A dielectric multilayer film (II) formed by alternately laminating silica (SiO ₂ ) layers and titania (TiO ₂ ) layers (26 layers in total) on both sides of the obtained base material in the same procedure as in Comparative Example 1. It was formed to obtain an optical filter having a thickness of about 0.105 mm.

The spectral transmittance of the obtained optical filter was measured to evaluate the optical characteristics. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was produced, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 18 and Table 4. In the optical filter obtained in Comparative Example 2, it was confirmed that ghosts, which are considered to be caused by near-infrared reflection by the dielectric multilayer film of the optical filter and reflection of the cover glass, were generated.

[Comparative Example 3]
A substrate made of a transparent resin substrate was obtained under the same procedure and conditions as in Comparative Example 1. Subsequently, a dielectric multilayer film (I) was formed on both surfaces of the obtained base material under the same procedure and conditions as in Example 11, and a similar dielectric multilayer film (I) was further formed on the other surface of the base material. I) was formed, and an optical filter having a thickness of about 0.101 mm was obtained.

The spectral transmittance of the obtained optical filter was measured to evaluate the optical characteristics. Further, using the obtained optical filter, a camera module incorporating the optical filter at the position shown in FIG. 2B was created, and flare evaluation, color shading evaluation, and ghost evaluation of the camera image were performed. The results are shown in FIG. 19 and Table 4. It was confirmed that the optical filter obtained in Comparative Example 3 did not sufficiently absorb the near-infrared wavelength region and was inferior in the flare suppression effect, and the near-infrared reflection and the reflection of the cover glass by the dielectric multilayer film of the optical filter were confirmed. The occurrence of ghosts, which is thought to be caused by the above, was confirmed.

The composition of the base material in Table 4, the symbols of various compounds, and the drying conditions of the film [(transparent) resin substrate or resin support] are as follows.
<Form of base material>
Form (1): Transparent resin substrate containing compound (A) Form (2): Transparent resin substrate containing compound (A) having resin layers on both sides Form (3): Compound on both sides of resin support Form having a transparent resin layer containing (A) (4): Form having a transparent resin layer containing compound (A) on one side of a transparent glass substrate (5): Compound on one side of a near-infrared absorbing glass substrate Form (6) having a transparent resin layer containing (A): Form having antireflection layers on both sides of a transparent resin substrate containing compound (A) (7): Compound (A) and near-infrared absorbing dye (X) Transparent resin substrate containing: Form (8): A transparent resin substrate containing the compound (A) and having a | X _b- X _a | of less than 100 nm has near-infrared reflective layers on both sides (comparative example).
Form (9): Antireflection layers are provided on both sides of a transparent resin substrate having | X _b- X _a | of less than 100 nm, which contains the compound (A) (comparative example).
Form (10): A transparent resin substrate containing the compound (A) and having | X _b- X _a | of less than 100 nm (comparative example).

<Glass substrate>
Glass substrate (1): Transparent glass substrate "OA-10G (thickness 150 μm)" cut to a size of 60 mm in length and 60 mm in width (manufactured by Nippon Electric Glass Co., Ltd.)
Glass substrate (2): Near-infrared absorbing glass substrate cut to a size of 60 mm in length and 60 mm in width "BS-11 (manufactured by Matsunami Glass Industry Co., Ltd.) polished to a thickness of 120 μm"

<Resin support>
Resin support (1): A transparent resin substrate made of resin A having a thickness of 0.1 mm, a length of 60 mm, and a width of 60 mm.

<Near infrared absorbing pigment>
≪Compound (A) ≫
Compound (A1-1): Compound represented by the formula (A1-1) (absorption maximum wavelength 712 nm in dichloromethane)
Compound (A1-2): Compound represented by the formula (A1-2) (absorption maximum wavelength in dichloromethane, 686 nm).
Compound (A3-1): Compound represented by the formula (A3-1) (absorption maximum wavelength in dichloromethane, 738 nm)
Compound (A2-1): Compound represented by the formula (A2-1) (absorption maximum wavelength in dichloromethane, 776 nm)
Compound (C2-2): Compound represented by the formula (C2-2) (absorption maximum wavelength in dichloromethane, 760 nm)

≪Other pigments (X) ≫
Near-infrared absorbing dye (X): Compound represented by formula (X) (maximum absorption wavelength in dichloromethane 813 nm)

<Solvent>
Solvent (1): Methylene chloride

<Film drying conditions>
Condition (1): 20 ° C / 8hr → 100 ° C / 8hr under reduced pressure

1 ... Optical filter, 2, 2'... Light, 3 ... Spectral photometer, 21, 23 ... Direct light, 22, 24 ... Scattered incident light, 100 ... Camera module, 102 ... Housing, 103 ... Casing, 104 ... Optical lens group, 106 ... Imaging element, 108 ... Near infrared light reflector, 109 ... Cover glass, 110 ... Near-infrared light absorber, 111 ... optical filter, 112 ... transparent resin base material, 114 ... antireflection layer (NIR), 116 ... transparent base material, 118 ... transparent resin layer, 120 ... transparent base material, 122 ... antireflection layer, 124 ... reflection layer, 126 ... pixel, 128 ... photodiode, 130 ... color filter layer, 132 ... microlens Array, 134 ... Wiring layer, 200 ... Camera image, 202 ... White plate, 204 ... Example of the central part of the white plate, 206 ... Example of the edge of the white plate, 208 ... -Camera image, 210 ... light source, 212 ... example of flare around the light source, 214 ... camera image, 216 ... light source, 218 ... example of ghost around the light source

Claims (11)

A cover glass having a near-infrared light reflecting portion that reflects light in the near-infrared region arranged on the incident side of light, an optical lens group, and
An image sensor that receives light incident through the optical lens group and
A near-infrared light absorber that absorbs light in the near-infrared region,
Including
The near-infrared light absorbing unit is a camera module composed of an optical filter containing a cycloolefin resin having a refractive index of 1.52 or more and less than 1.54 and a compound that absorbs near-infrared rays. Claim 1 in which the near-infrared light reflecting portion and the near-infrared light absorbing portion are arranged in order from the light incident side of the cover glass having the near-infrared light reflecting portion and the near-infrared light absorbing portion. The camera module described in. The cover glass having the near-infrared light reflecting portion includes a glass base material, an antireflection layer that prevents light in the visible region from being reflected on at least one surface of the glass base material, and near infrared rays on at least one surface. The camera module according to claim 1 or 2, further comprising a reflective layer that reflects light in the region. The camera module according to any one of claims 1 to 3, wherein the near-infrared light absorption unit is a cycloolefin resin in which the compound is dispersed. The camera module according to any one of claims 1 to 4, wherein the near-infrared light absorbing unit has an antireflection layer for preventing reflection of light in the visible light region on an incident surface of light. The camera module according to any one of claims 1 to 5, wherein the camera module satisfies the following requirements (1) and (2).
Requirements (1) R _NIR-5 <30
Requirement (2) R _NIR-30 <30
here,

RA5 (λ): Reflectance when incident on the optical filter at wavelength λ nm at 5 degrees from the optical lens group side RB5 (λ): When incident on the cover glass at wavelength λ nm at 5 degrees from the optical lens group side Is the reflectance of

RA30 (λ): Reflectance when incident on the optical filter at wavelength λ nm at 30 degrees from the optical lens group side RB30 (λ): Reflectance when incident on the cover glass at wavelength λ nm at 30 degrees from the optical lens group side The reflectance of. The camera module according to any one of claims 1 to 6, which satisfies the following requirements (3) and (4).
Requirements (3) T _NIR-5 <30
Requirement (4) T _NIR-30 <30
here,

TA5 (λ): Transmittance when incident on the optical filter at wavelength λ nm at 5 degrees from the optical lens group side TB5 (λ): Transmittance on the cover glass at wavelength λ nm at 5 degrees from the side opposite to the optical lens group It is the transmittance when it is incident.

TA30 (λ): Transmittance when incident on the optical filter at wavelength λ nm at 30 degrees from the optical lens group side TB30 (λ): Transmittance on the cover glass at wavelength λ nm 30 degrees from the side opposite to the optical lens group side It is the transmittance when it is incident at. Claims 1 to 7 where the compound that absorbs near infrared rays is at least one compound selected from the group consisting of a squarylium compound, a phthalocyanine compound, a naphthalocyanine compound, a croconium compound, and a cyanine compound. The camera module according to any one of the above. The camera module according to any one of claims 1 to 8, wherein the optical filter has a maximum absorption wavelength in the wavelength range of 650 nm to 800 nm. The optical filter contains a compound having an absorption maximum in a wavelength region of 650 m or more and 715 nm or less, the compound is a squarylium compound, a compound having an absorption maximum in a wavelength region of more than 715 nm and 750 nm or less is a phthalocyanine compound, and a wavelength of more than 750 nm. The camera module according to any one of claims 1 to 9, wherein the compound having an absorption maximum in a region of 800 nm or less is a squarylium-based compound. An electronic device having the camera module according to any one of claims 1 to 10.