JP7251423B2 - Optical components and camera modules - Google Patents

Description

The present invention relates to an optical member and a camera module using the optical member.

2. Description of the Related Art Image sensors such as CCD and CMOS are used in solid-state imaging devices such as video cameras, digital still cameras, mobile phones with camera functions, and the like. These image sensors use silicon photodiodes in their light receiving portions that are sensitive to near-infrared light that cannot be detected by the human eye. For these image sensors, it is necessary to perform luminosity correction to make colors look natural to the human eye, and optical filters that selectively transmit or block light in a specific wavelength range, such as near-infrared cut filters, are used. There are many things.

As such optical filters, filters manufactured by various methods have been conventionally used. For example, an absorbing glass type infrared cut filter (Patent Document 1) in which copper oxide is dispersed in phosphate glass, or a resin type infrared cut filter (Patent Document 2) having a layer in which a dye having absorption in the near-infrared band is dispersed. , a glass substrate-coated infrared cut filter having a transparent dielectric substrate (glass substrate), an infrared reflective layer, and an infrared absorbing layer (Patent Document 3), using a transparent resin as the substrate, and having a wavelength of 600 nm or more in the transparent resin A resin-type near-infrared cut filter (Patent Document 4) containing a dye having an absorption maximum in the region of 800 nm or less and using a dielectric multilayer film having near-infrared reflective performance on both sides of the substrate (Patent Document 4), with a glass substrate at a wavelength of 695 nm. Various types of infrared cut filters are known, such as a glass substrate coating type infrared cut filter provided with a resin layer containing a dye having absorption in the vicinity of the region of 720 nm or less (Patent Document 5).

In recent years, camera modules have become thinner, and there is a demand for both further reduction in thickness and an optical telephoto function. A reflective imaging camera module (Patent Literature 6) is known that is thin but can secure an optical path length for optical telephoto.

WO2011/071157 Japanese Patent Application Laid-Open No. 2008-303130 JP 2014-52482 A JP 2011-100084 A JP 2014-63144 A Japanese Patent Application Laid-Open No. 2007-19860

In an optical filter having a substrate surface that reflects near-infrared light, such as the optical filter described in the above-mentioned publication, a so-called ghost occurs, which is a phenomenon in which the light reflected by the surface of the optical filter enters the image sensor again. do. That is, image defects may occur in imaging using a camera module equipped with this optical filter. In particular, near-infrared rays, to which human visibility is low, cause serious image defects because the image is different from the image visible to the human eye.

In order to prevent the above image defects, an antireflection layer is sometimes provided on the optical filter, but in such a case, the thickness of the optical filter is greatly affected. In recent years, camera modules have been required to achieve both slimness and high-performance optical telephoto functions. .

The present invention has been made based on the circumstances as described above, and selectively reflects visible light in a specific wavelength region in order to improve the problems of image defects and thinness associated with existing optical filters. An object of the present invention is to provide an optical member that suppresses reflection of light in a specific wavelength range and a camera module using the optical member.

The invention made to solve the above problems is provided with a reflecting surface, and the average reflectance of non-polarized light incident on the reflecting surface at 45° from the vertical is 80% or more in the wavelength range of 400 nm or more and 640 nm or less. , 8% or less in the wavelength region of 700 nm or more and 1150 nm or less.

Another invention made to solve the above-mentioned problems is a camera module comprising an optical member, the optical member comprising a reflecting surface, and a non-polarized light beam incident on the reflecting surface at an angle of 45° from the vertical. The camera module has an average reflectance of 80% or more in the wavelength range of 400 nm or more and 640 nm or less and 8% or less in the wavelength range of 700 nm or more and 1150 nm or less.

Here, "average reflectance" means the ratio of specular reflection to the amount of incident non-polarized light, that is, the ratio of the amount of non-polarized light reflected at the same angle as the incident angle of the non-polarized light.

The optical member according to the present invention reflects incident light in the wavelength region of 400 nm or more and 640 nm or less and converts the optical path, but suppresses reflection of light in the wavelength region of 700 nm or more and 1150 nm or less that is incident on the optical member. be. The optical member selectively reflects visible light in a specific wavelength range, but can suppress reflection of light in a specific wavelength range. Moreover, the camera module according to the present invention can be made thinner while suppressing image defects.

FIG. 1 is a schematic front view showing an optical member according to an embodiment of the invention. FIG. 2 is a schematic front view showing an optical member according to another embodiment of the invention. FIG. 3 is a schematic front view showing an optical member according to another embodiment of the invention. 4 is a schematic perspective view showing the optical member of FIG. 1. FIG. FIG. 5A is a schematic front view showing an optical member having a dielectric multilayer film according to another embodiment of the invention. FIG. 5B is a schematic front view showing an optical member having a dielectric multilayer film according to another embodiment of the invention. FIG. 5C is a schematic front view showing an optical member having a dielectric multilayer film according to another embodiment of the invention. FIG. 5D is a schematic front view showing an optical member having a dielectric multilayer film according to another embodiment of the invention. FIG. 5E is a schematic front view showing an optical member having a dielectric multilayer film according to another embodiment of the invention. FIG. 5F is a schematic front view showing an optical member having a dielectric multilayer film according to another embodiment of the invention. 6A is a schematic front view showing optical paths in the optical member of FIG. 5B. FIG. FIG. 6B is a schematic perspective view showing optical paths in the optical member of FIG. 5B. FIG. 7A is a schematic front view showing an optical member having a light shielding film according to another embodiment of the invention. FIG. 7B is a schematic perspective view showing an optical member having a light shielding film according to another embodiment of the invention. FIG. 8A is a schematic perspective view showing an optical member having uneven portions according to another embodiment of the present invention. FIG. 8B is a schematic top view showing an optical member having uneven portions according to another embodiment of the present invention. FIG. 8C is a schematic bottom view of an optical member having uneven portions according to another embodiment of the present invention, viewed from the vertical direction of the slope. FIG. 9A is a schematic plan view showing one aspect of the camera module according to the embodiment of the invention. FIG. 9B is a schematic plan view showing one aspect of the camera module according to the embodiment of the invention. FIG. 9C is a schematic plan view showing one aspect of the camera module according to the embodiment of the invention. FIG. 9D is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9E is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9F is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9G is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9H is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9I is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9J is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9K is a schematic plan view showing one aspect of the camera module according to the embodiment of the present invention. FIG. 9L is a schematic plan view showing one aspect of the camera module according to the embodiment of the invention. FIG. 10A is a conceptual diagram showing a method of measuring the transmittance of an unpolarized light incident at 45° of an optical member. FIG. 10B is a conceptual diagram showing a method of measuring the reflectance of an unpolarized light incident at 45° on an optical member. FIG. 10C is a conceptual diagram showing a method of measuring the reflectance of an unpolarized light incident at 5° on an optical member. FIG. 10D is a conceptual diagram showing a method of measuring the reflectance of an unpolarized light incident at 45° on an optical member made of a prismatic substrate. FIG. 10E is a conceptual diagram showing a method of measuring the spectral transmission efficiency of an optical member. FIG. 10F is a conceptual diagram showing a method of measuring 100% of the light amount used as a reference in spectral transmission efficiency measurement. FIG. 10G is a conceptual diagram showing a method of measuring spectral transmission efficiency through a cover glass. FIG. 11 is a graph showing the wavelength-dependent sensitivity of each sensor pixel for blue, green, and red.

[Optical member]
The optical member has a reflective surface, and the average reflectance of non-polarized light incident on the reflective surface at an angle of 45° is 80% or more in the wavelength region of 400 nm or more and 640 nm or less, and the wavelength of 700 nm or more and 1150 nm or less. area is 8% or less.

The optical member reflects light in the wavelength region of 400 nm or more and 640 nm or less, but suppresses reflection of light in the wavelength region of 700 nm or more and 1150 nm or less. Here, "reflect" means a reflectance of 65% or more in specular reflection, and "suppress reflection" means a reflectance of 20% or less in specular reflection. The light in the wavelength range of 400 nm or more and 640 nm or less, which has entered the optical member, is reflected by the reflecting surface and has its optical path changed. In addition, reflection of light in the wavelength region of 700 nm or more and 1150 nm or less incident on the optical member is suppressed, and unreflected light is transmitted through the optical member or absorbed by the optical member. For example, when light is incident on the reflecting surface at an angle of 45° from the perpendicular, light in the wavelength range of 400 nm or more and 640 nm or less is reflected at a reflection angle of 45° by specular reflection. On the other hand, the light in the wavelength region of 700 nm or more and 1150 nm or less is suppressed from such an optical path change. With this optical member, for example, it is possible to combine the function of a reflecting mirror that reflects visible light and the function of an optical filter that shields near-infrared light with a single member.

The optical member can specularly reflect light in a wavelength range of 400 nm or more and 640 nm or less, and the specular reflection can change the optical path of the visible light. For example, when the optical member is used in a camera module, a sufficient optical path length can be secured by performing the optical path conversion, so a zoom lens or the like can be incorporated in the optical path.

In addition, the optical member can suppress reflection of light in the wavelength range of 700 nm or more and 1150 nm or less, in which the sensitivity of silicon photodiodes used in optical sensors is high and the visibility of humans is low. When the optical member is used in a camera module, reflection of light in the wavelength range of 700 nm or more and 1150 nm or less can be suppressed, and detection by a silicon photodiode can be prevented. As a result, the camera module has good luminosity correction for making red color look natural to the human eye. In addition, it is possible to suppress the occurrence of image defects such as ghosts caused by the light reflected by the optical filter when the optical filter is used.

The optical member preferably has a maximum reflectance of 20% or less in a wavelength region of 700 nm or more and 1150 nm or less for a non-polarized light incident on the reflecting surface at an angle of 45°. Thereby, it is possible to suppress the reflection of light in the wavelength range of 700 nm or more and 1150 nm or less.

The optical member preferably has a reflectance of 65% or more at a wavelength of 650 nm for a non-polarized light beam incident at 45° perpendicular to the reflecting surface. As a result, the light with a wavelength of 650 nm can be mirror-reflected, and the specular reflection can change the optical path of the light with a wavelength of 650 nm, which is highly visible to humans.

[Reflective surface]
The mode of the reflecting surface is not limited. For example, the reflective surface may be formed on the base material, or the reflective surface may be formed on the slope of the prism. When the reflective surface is formed on the slope of the prism, the shape of the prism is not limited. The reflecting surface may be formed on the surface of a single-layer resin or laminated film, or the reflecting surface may be formed by coating a base material.

[Base material]
The optical member preferably includes a substrate and a reflective layer forming the reflective surface, and the substrate preferably contains a compound having an absorption maximum in a wavelength region of 680 nm or more and 1200 nm or less. The compound contained in the base material absorbs light in the range of 680 nm or more and 1200 nm or less, so that the optical member has a high sensitivity of a silicon photodiode and a wavelength range of 700 nm or more and 1150 nm or less where human visibility is low. Reflection of light can be suppressed. The material, shape, and the like of the substrate are not particularly limited as long as they do not impair the effects of the present invention, but transparent inorganic materials, transparent resins, and the like can be used. Whether the optical member is formed from one base material as shown in FIG. 5A or FIG. 5B, or is formed from a plurality of base materials as shown in FIG. 5C, FIG. 5D or FIG. It may be formed from a substrate having a curved surface.

[Reflection layer]
The mode of the reflective layer is not limited. For example, a dielectric multilayer film, a high refractive index material layer containing a high refractive index material, a medium refractive index material layer containing a medium refractive index material, a low refractive index material layer containing a low refractive index material, a metal layer, a semiconductor layer, and a high refractive index It may be in the form of a resin layer in which a material, medium refractive index material, or low refractive index material is dispersed. Moreover, the aspect which combined the several reflective layer may be sufficient. Furthermore, the reflective layer may be laminated on one surface of the substrate, or the reflective layer may be laminated on a plurality of surfaces. When the reflective layer is laminated on the substrate, the reflective surface may be formed on the surface of the reflective layer, or may be formed on the surface where the reflective layer and the substrate are in contact with each other.

[Compound]
The compound is not particularly limited as long as it has an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less. For example, squarylium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, croconium-based compounds, hexaphyrin-based compounds, azo-based compounds, naphthoquinone-based compounds, polymethine-based compounds, oxonol-based compounds, pyrrolopyrrole-based compounds, triarylmethane-based dyes , diimonium compounds, dithiol complex compounds, dithiolene complex compounds, dipyrromethene compounds, mercaptophenol complex compounds, mercaptonaphthol complex compounds, and the like. In addition, the said compound may be used individually by 1 type, and may be used in combination of 2 or more type.

The compound is preferably contained in the range of 0.01% by mass or more and 80.0% by mass or less with respect to the base material. If the content of the base material is within the above range, appropriate optical properties are likely to be obtained.

[prism]
The optical member preferably includes a prism having a triangular cross section with an apex angle of 70° or more and 120° or less. In such a case, the reflective surface is formed on a slope facing the apex angle of the prism. As a result, specular reflection can be performed at a constant angle of reflection without changing the oblique angle of the reflecting surface. The apex angle is more preferably 80° or more and 110° or less, and more preferably substantially right angle.

[Light incident surface]
The prism may further include a light incident surface through which light incident toward the reflecting surface is transmitted. As for the optical characteristics of the light incident surface, it is more preferable that the average reflectance of non-polarized light incident on the light incident surface at an angle of 5° is 20% or less in the wavelength region of 400 nm or more and 640 nm or less. If the optical characteristics of the light incident surface are within the above range, when light is incident on the light incident surface in a substantially vertical direction, the visible light in the wavelength range of 400 nm or more and 640 nm or less on the light incident surface Reflection can be prevented.

As for the optical characteristics of the light incident surface, the average reflectance of non-polarized light incident on the light incident surface at 5° perpendicular to the light incident surface is preferably 20% or less in the wavelength region of 700 nm or more and 1150 nm or less, and preferably 10%. It is more preferably 5% or less, more preferably 5% or less. If the optical characteristics of the light incident surface are within the above range, the light in the wavelength range of 700 nm or more and 1150 nm or less is reflected on the light incident surface when the light is incident on the light incident surface in a substantially vertical direction. can be prevented.

[Light emitting surface]
The prism may further include a light output surface through which the light reflected by the reflecting surface is transmitted. As for the optical characteristics of the light output surface, the average reflectance of non-polarized light incident on the light output surface at an angle of 5° is preferably 20% or less, and preferably 10% or less, in the wavelength region of 750 nm or more and 1150 nm or less. and more preferably 5% or less. If the optical characteristics of the light exit surface are within the above range, the wavelength range of 750 nm or more and 1150 nm or less on the light exit surface when the light reflected by the reflection surface is incident on the light exit surface in a direction substantially perpendicular to the light exit surface. of light can be prevented.

[Spectral transmission efficiency]
The prism has an average transmission efficiency of 80 in the wavelength region of 400 nm or more and 640 nm or less for non-polarized light rays that are incident on the light entrance surface, reflected at an angle of 45° from the perpendicular to the reflection surface, and transmitted through the light exit surface. % or more, 8% or less in a wavelength range of 700 nm or more and 1150 nm or less, a transmittance of 80% or more at a wavelength of 600 nm, and a maximum transmission efficiency of 20% or less in a wavelength range of 700 nm or more and 1150 nm or less. Here, "average transmission efficiency" refers to the ratio of the amount of non-polarized light emitted from the light exit surface after the non-polarized light is reflected by the reflecting surface to the amount of non-polarized light incident on the light entrance surface. If the optical characteristics of the prism are within the above range, the light entering the prism is reflected by the reflective surface and transmitted through the light emitting surface, and the light in the wavelength region of 700 nm or more and 1150 nm or less, where human visibility is low. Transmission can be suppressed, and light in a wavelength region of 400 nm or more and 640 nm or less, which has high human visibility, can be transmitted.

[The camera module]
The camera module is a camera module comprising an optical member, wherein the optical member comprises a reflecting surface, and the average reflectance of non-polarized light rays incident on the reflecting surface at an angle of 45° from the vertical is 400 nm or more and 640 nm or less. is 80% or more in the wavelength region of , and 8% or less in the wavelength region of 700 nm or more and 1150 nm or less.

According to the camera module, visibility correction is performed by suppressing reflection on the reflective surface of light in the wavelength range of 700 nm or more and 1150 nm or less, where human visibility is low, so that red is a natural color to the human eye. become good. In addition, since the camera module can secure a sufficient optical path length by converting the optical path of light in the wavelength range of 400 nm or more and 640 nm or less, a zoom lens or the like can be incorporated in the optical path, and an optical telephoto Higher performance functions are possible. Furthermore, the camera module can omit an optical filter that shields near-infrared light, and can suppress the occurrence of image defects such as ghosts caused by reflected light when an optical filter is used. The camera module can easily be made thinner by eliminating the optical filters described above.

The camera module may further comprise an optical sensor. The optical sensor can have, for example, a light receiving surface in which a large number of photodiodes are arranged in a matrix. The optical sensor can receive the light reflected by the optical member, photoelectrically convert the light, and output an imaging signal.

The camera module may further include a lens, and may not have an optical filter between the lens and the optical sensor. By reducing the number of optical filters, it is easy to reduce the thickness of the camera module.

The camera module may further comprise a periscope-shaped optical system housing unit. In the optical system housing unit, the plurality of optical members are arranged such that the optical paths are substantially perpendicular. As a result, a longer optical path length can be ensured, so that it is possible to realize a high-performance optical telephoto function and a reduction in thickness. Further, the optical system housing unit can arrange the lens, the planar optical member, etc. between the one optical member and the other optical member.

The camera module is useful for solid-state imaging devices such as digital still cameras, mobile phone cameras, digital video cameras, surveillance cameras, vehicle-mounted cameras, and web cameras. Since the optical member provided in the camera module enables both the optical path conversion of visible light and the shielding of near-infrared light, the camera module is designed to reduce the size and thickness of the solid-state imaging device illustrated above. It is easy to achieve both high performance of the optical telephoto function.

The camera module may comprise an absorber that absorbs light in a specific wavelength range. The absorber is provided on an optical path of light that has entered the optical member and has passed through the reflecting surface without being reflected. As the optical characteristics of the absorber, the average reflectance for unpolarized light incident on the absorber at 5° from the vertical direction is preferably 10% or less in the wavelength region of 700 nm or more and 1150 nm or less, and is 5% or less. and more preferred. If the optical properties of the absorber are within the above range, it is possible to absorb light that has passed through the reflecting surface without being reflected, thereby preventing irregular reflection within the camera module.

The camera module may include a near-infrared sensor that receives light in a specific wavelength range. The near-infrared sensor is provided on the optical path of the light that has entered the optical member and has passed through the reflecting surface without being reflected. It is possible to sense the brightness around the camera module by receiving light that has passed through the reflecting surface without being reflected. As a result, it is possible to integrate the light receiving portion for solid-state imaging and the light receiving portion for ambient light, and it is possible to provide a camera module with excellent design.

[Details of the embodiment of the present invention]
Hereinafter, optical members and camera modules according to embodiments of the present invention will be described in detail with reference to the drawings.

[Details of Embodiment of Optical Member]
The optical member 1 shown in FIG. 1 comprises a prism 5 having a right isosceles triangular cross section. The prism 5 is in the shape of a right-angled triangular prism and has a reflecting surface 2 , a light incident surface 3 and a light exiting surface 4 . Two planes orthogonal to each other constitute the light entrance surface 3 and the light exit surface 4, and the reflective surface 2 is an inclined surface that intersects the light entrance surface 3 and the light exit surface 4 at an acute angle (45° in the embodiment of FIG. 1). Configure.

Light incident from the light incident surface 3 of the optical member 1 passes through the light incident surface 3 and is reflected by the reflecting surface 2 . Light reflected by the reflecting surface 2 is transmitted through the light emitting surface 4 and emitted from the optical member 1 . As for the optical characteristics of the reflecting surface 2, the average reflectance of non-polarized light incident on the reflecting surface 2 at an angle of 45° is 80% or more in the wavelength range of 400 nm or more and 640 nm or less, and the wavelength range of 700 nm or more and 1150 nm or less. is 8% or less.

The optical member 1 can specularly reflect visible light of 400 nm or more and 640 nm or less on the reflecting surface 2 , and can change the optical path by such specular reflection. In addition, the optical member 1 can suppress reflection of light in the wavelength range of 700 nm or more and 1150 nm or less, where the sensitivity of a silicon photodiode is high and human visibility is low. Furthermore, the optical member 1 can suppress the loss of the amount of visible light of 400 nm or more and 640 nm or less due to the optical path change.

The optical characteristics of the reflective surface 2 in the optical member 1 are such that the maximum reflectance of non-polarized light incident on the reflective surface 2 at 45° from the vertical is 20% or less in the wavelength region of 700 nm or more and 1150 nm or less. . When light incident on the optical member 1 is incident on the reflecting surface 2 at an angle of 45° from the vertical, the optical member 1 can prevent reflection of light in the wavelength range of 700 nm or more and 1150 nm or less on the reflecting surface 2. can. As a result, the optical member 1 can suppress specular reflection and optical path change for light in the wavelength region of 700 nm or more and 1150 nm or less, to which silicon photodiodes used in optical sensors have high sensitivity.

The optical characteristics of the reflecting surface 2 of the optical member 1 are preferably such that the reflectance of non-polarized light incident on the reflecting surface 2 at an angle of 45° from the vertical is 65% or more at a wavelength of 650 nm. When light incident on the optical member 1 is incident on the reflecting surface 2 at an angle of 45° from the vertical, the optical member 1 can change the optical path of light with a wavelength of 650 nm, which is highly visible to humans, by specular reflection. .

According to the optical member 1, both the optical path conversion of visible light and the shielding performance of near-infrared light are achieved by one member. Furthermore, according to the optical member 1, for example, it is possible to combine the function of a reflecting mirror that reflects visible light and the function of an optical filter that shields near-infrared light with a single member.

In the above embodiment, the prism 5 has a right-angled isosceles triangular cross section, but the shape of the prism 5 is not limited to this as long as it has a triangular cross section. One of the apex angles in the triangular cross section is preferably 70° or more and 120° or less, more preferably 80° or more and 110° or less, and even more preferably a substantially right angle. When the prism 5 has a right-angled triangular cross section, the two sides forming the right angle may have the same length or different lengths. Also, the material of the prism 5 can be the material used for the substrate, which will be described later.

In the embodiment of the optical member 1 shown in FIG. 1, a configuration including a prism having a right-angled triangular cross section has been described, but the shape of the prism is not limited to a triangular prism shape, and may be quadrilateral or polygonal. It may be in the form of a film, a thin film, a flat plate, a single-layer resin, a laminate structure, or the like. For example, it may be in the form of a flat plate having a reflecting surface 12 like the optical member 11 shown in FIG.

When the optical member 11 has a plate shape, the thickness is not particularly limited and may be appropriately selected according to the desired application. 15 mm or less, particularly preferably 0.02 mm or more and 0.1 mm or less. When the thickness of the optical member is within the above range, the ease of handling is excellent, and the weight of a camera module or the like using the obtained optical member can be reduced.

Like an optical member 21 shown in FIG. 3, it may have a reflective layer 23 forming a reflective surface 22 . For example, reflective layer 23 can be laminated to substrate 24 . The base material 24 preferably contains a compound having an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less. Since the compound absorbs light in the range of 680 nm to 1200 nm, the optical member 21 has high sensitivity of silicon photodiodes and suppresses reflection of light in the wavelength range of 700 nm to 1150 nm, where human visibility is low. can be done.

The compound is not particularly limited as long as it has an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less. For example, squarylium-based compounds, phthalocyanine-based compounds, naphthalocyanine-based compounds, croconium-based compounds, hexaphylline-based compounds, azo-based compounds, naphthoquinone-based compounds, polymethine-based compounds, oxonol-based compounds, pyrrolopyrrole-based compounds, diimonium-based compounds, dithiols complex-based compounds, dithiolene complex-based compounds, dipyrromethene-based compounds, mercaptophenol complex-based compounds, mercaptonaphthol complex-based compounds, copper oxide-based compounds, copper phosphate-based compounds, copper phosphonate-based compounds, and the like. The above compound is preferably contained in the range of 0.01 mass % or more and 80.0 mass % or less with respect to the base material 24 .

The squarylium-based compound is not particularly limited as long as it does not impair the effects of the present invention. Examples thereof include squarylium-based dyes having a squaric acid structure. Some squarylium-based compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less. can be used as the compound contained in the substrate 24 by using a squarylium-based compound having an absorption maximum in the wavelength region of .

The phthalocyanine-based compound or the naphthalocyanine-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include metal phthalocyanine and metal naphthalocyanine. As the central metal, copper, zinc, cobalt, vanadium, iron, nickel, tin, silver, magnesium, sodium, lithium, lead and the like can be used. Some of the phthalocyanine-based compounds or naphthalocyanine-based compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less. By selecting a compound, or by using a phthalocyanine-based compound or a naphthalocyanine-based compound having an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less, it can be used as the above-mentioned compound contained in the base material 24 .

The croconium-based compound is not particularly limited as long as it does not impair the effects of the present invention. Examples thereof include croconium-based dyes having a croconium structure. Some of the croconium-based compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less. By using a croconium-based compound having an absorption maximum in the wavelength region of , it can be used as the above compound contained in the base material 24 .

The hexaphyrin-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include hexaphyrin and florin-type hexaphyrin. Some hexaphyrin-based compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less. By using a hexaphylline-based compound having an absorption maximum in a wavelength range of 1200 nm or less, it can be used as the compound contained in the base material 24 .

The azo compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include diazo dyes and triaz dyes. Some of the azo compounds include those that do not have an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less, but select an azo compound that has an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less, or 680 nm or more and 1200 nm or less. can be used as the compound contained in the substrate 24 by using an azo compound having an absorption maximum in the wavelength region of .

The naphthoquinone-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include 1,4-disubstituted 5,8-naphthoquinone derivatives. Some naphthoquinone-based compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less. By using a naphthoquinone-based compound having an absorption maximum in the wavelength region of , it can be used as the compound contained in the base material 24 .

The polymethine-based compound is not particularly limited as long as it does not impair the effects of the present invention. The oxonol-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include oxonols such as oxonol VI. Some polymethine compounds or oxonol compounds do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less. It can be used as the above compound contained in the base material 24 by selecting or using together a polymethine-based compound or an oxonol-based compound having an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less.

The pyrrolopyrrole-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include compounds having a diketopyrrolopyrrole structure. Some of the pyrrolopyrrole compounds include those that do not have an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less, but select a pyrrolopyrrole compound that has an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less, or 680 nm or more By using a pyrrolopyrrole-based compound having an absorption maximum in a wavelength region of 1200 nm or less, it can be used as the above compound contained in the base material 24 .

The diimmonium-based compound is not particularly limited as long as it does not impair the effects of the present invention. Diimmonium-based compounds described in paragraphs [0049] to [0061] of International Publication No. 2018/043564, and the like. Some of the diimmonium-based compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less, but select a diimonium-based compound that has an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less, or 680 nm or more and 1200 nm or less. can be used as the above compound contained in the base material 24 by using a dimonium-based compound having an absorption maximum in the wavelength region of .

The dithiol complex-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include dithiol metal complexes. Examples of the dithiolene complex-based compound include dithiolene metal complexes. A transition metal or the like can be used as the central metal. Some of the dithiol complex compounds or dithiolene complex compounds do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less, but dithiol complex compounds or dithiolenes that have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less By selecting a complex-based compound or using a dithiol complex-based compound or a dithiolene complex-based compound having an absorption maximum in a wavelength range of 680 nm or more and 1200 nm or less, it can be used as the compound contained in the substrate 24 .

The dipyrromethene-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include dipyrromethene-based boron complex compounds. Some of the dipyrromethene compounds include those that do not have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less, but dipyrromethene compounds that have an absorption maximum in the wavelength range of 680 nm or more and 1200 nm or less are selected, or 680 nm or more and 1200 nm or less. By using a dipyrromethene-based compound having an absorption maximum in the wavelength region of , it can be used as the above compound contained in the base material 24 .

The mercaptophenol complex-based compound is not particularly limited as long as it does not impair the effects of the present invention, and examples thereof include metal complexes of mercaptophenol derivatives. Examples of the mercaptonaphthol complex compounds include metal complexes of mercaptonaphthol derivatives. A transition metal or the like can be used as the central metal. Some of the mercaptophenol complex compounds or mercaptonaphthol complex compounds do not have an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less, but mercaptophenol complex compounds that have an absorption maximum in the wavelength region of 680 nm or more and 1200 nm or less By selecting a compound or a mercaptonaphthol complex-based compound, or using together a mercaptophenol complex-based compound or a mercaptonaphthol complex-based compound having an absorption maximum in a wavelength range of 680 nm or more and 1200 nm or less, the above compound contained in the base material 24 can be used as

The above compound can be synthesized by a generally known method. As the synthesis method, for example, JP-A-60-228448, JP-A-1-146846, JP-A-1-228960, JP-A-4081149, JP-A-63-124054, "phthalocyanine -Chemistry and function-" (IPC, 1997), JP 2007-169315, JP 2009-108267, JP 2010-241873, JP 3699464, JP 4740631 The methods described can be mentioned.

[Base material]
Substrate 24 may be a transparent inorganic material. The transparent inorganic material is not particularly limited, but quartz, borosilicate glass, silicate glass, chemically strengthened glass, physically strengthened glass, soda glass, phosphate glass, alumina glass, sapphire glass, colored glass, etc. is mentioned. These commercially available products include SCHOTT D263, BK7, B270, KG1 or KG1 cut into the shape of the base material, KG3 or KG3 cut into the shape of the base material, KG5 or KG5. Cut into the shape of the base material, C5000 manufactured by HOYA Co., Ltd. cut into the shape of the base material, CD5000 cut into the shape of the base material, E-CM500S in the shape of the base material Gorilla Glass, Willow Glass manufactured by Corning, BS1 to 11 and BS1 to 11 manufactured by Matsunami Glass Industry Co., Ltd. cut into the shape of the above base material, Hiceram manufactured by NGK Insulators, Ltd., etc. is mentioned. Among these, borosilicate-based glass or phosphate-based glass is preferable from the viewpoint of high visible light transmittance and excellent near-infrared shielding performance. , B270, KG1, KG3, KG5, etc. Examples of the phosphate-based glass include, but are not limited to, phosphate-copper salt-based glass containing copper atoms. Copper phosphate-based glasses containing copper atoms can be obtained, for example, by the methods described in JP-A-2015-522500, WO 2011/071157, and WO 2017/208679. As the phosphate-based glass, fluorophosphate-based glass containing fluorine atoms, which tends to have little change in optical properties in a high-temperature and high-humidity environment, is preferable.

Moreover, the material of the base material 24 may be a transparent resin. The transparent resin is not particularly limited as long as it does not impair the effects of the present invention. In order to obtain a base material capable of forming a multilayer film, the glass transition temperature (Tg) is preferably 110° C. or higher and 380° C. or lower, more preferably 110° C. or higher and 370° C. or lower, and still more preferably 120° C. or higher and 360° C. or lower. Some resins are mentioned. Further, when the Tg of the resin is 150° C. or more, even if the Tg is lowered by adding an additive to the resin at a high concentration, the resin can be used as a base material on which a dielectric multilayer film can be vapor-deposited at a high temperature. , is particularly preferred.

As the transparent resin, when a resin plate having a thickness of 0.05 mm made of only the resin is formed, the total light transmittance (JIS K7375) of the resin plate is preferably 50% or more and 96% or less, more preferably It is desirable to use a resin with a viscosity of 60% or more and 96% or less, particularly preferably 70% or more and 96% or less. If a resin having a total light transmittance in such a range is used, the substrate obtained exhibits good transparency as an optical film.

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

Examples of the transparent resin include cyclic polyolefin-based resins, aromatic polyether-based resins, polyimide-based resins, fluorene polyester-based resins, polycarbonate-based resins, polyamide-based resins, aramid-based resins, polysulfone-based resins, and polyethersulfone-based resins. Resins, polyparaphenylene resins, polyamideimide resins, polyethylene naphthalate resins, fluorinated aromatic polymer resins, (modified) acrylic resins, epoxy resins, silsesquioxane ultraviolet curing resins, maleimide resins Resins, alicyclic epoxy thermosetting resins, polyether ether ketone resins, polyarylate resins, allyl ester curable resins, acrylic UV curable resins, vinyl UV curable resins, silica formed by the sol-gel method and the like as a main component. Among these, cyclic polyolefin-based resins, aromatic polyether-based resins, fluorene polyester-based resins, polycarbonate-based resins, polyimide-based resins, fluorinated aromatic polymer-based resins, and acrylic UV-curable resins can be used to improve transparency. It is preferable in that an optical member having an excellent balance of properties (optical properties), heat resistance, reflow resistance, and the like can be obtained. One type of transparent resin may be used alone, or two or more types may be used.

A prism may be formed using the base material as in the optical member 1 shown in FIG. The optical member 1 has a length L of 0.5 mm or more and 100 mm or less, a width W of 0.5 mm or more and 100 mm or less, and a height H of 0.5 mm or more and 100 mm or less, more preferably 0.5 mm. 50 mm or less, width W is 0.5 mm or more and 50 mm or less, height H is 0.5 mm or more and 50 mm or less, more preferably length L is 0.5 mm or more and 20 mm or less, width W is 0.5 mm or more and 20 mm or less, height It is preferable that the height H is C0.5 mm or more and 20 mm or less.

[Method for producing base material]
When the base material 24 is a plate-shaped base material containing the transparent resin, the base material 24 can be formed by, for example, melt molding or cast molding. By coating with a coating agent such as a coating agent or an antistatic agent, a substrate having an overcoat layer laminated thereon can be produced.

When the substrate 24 is a substrate in which a transparent resin layer containing an additive or the transparent resin is laminated on a transparent inorganic support or a resin support, for example, a transparent inorganic support or a resin By melt-molding or cast-molding a resin solution containing additives on a support, the solvent is preferably removed by drying after coating by a method such as spin coating, slit coating, or inkjet, and if necessary, light is applied. By irradiating or heating, it is possible to produce a substrate in which the transparent resin layer is formed on a support made of a transparent inorganic material or a support made of a resin.

[Melt molding]
Specifically, when the base material 24 contains a resin and an additive, the melt-molding includes a method of melt-molding pellets obtained by melt-kneading the resin and the additive, and a method of melt-molding the resin and the additive. Examples include a method of melt-molding a resin composition containing the resin composition, and a method of melt-molding pellets obtained by removing the solvent from a resin composition containing additives, resins, solvents, and the like. Examples of melt molding methods include injection molding, melt extrusion molding, and blow molding. When the base material 24 contains a transparent inorganic material, a platinum crucible, a platinum-rhodium crucible, a gold crucible, an iridium crucible, an alumina porcelain crucible, or the like is used depending on the melting point and releasability of the inorganic material. Examples include a method in which a transparent inorganic material is melted and then molded by an overflow method, a float method, or the like.

[Cast molding]
Examples of cast molding include a method of casting a resin composition containing an additive, a resin, a solvent, etc. on a suitable support and removing the solvent. Also, after casting a curable composition containing additives, photocurable resins, thermosetting resins, etc. on a suitable support and removing the solvent, it is cured by an appropriate method such as ultraviolet irradiation or heating. It can be a method.

When the base material 24 is a plate-like base material made of the transparent resin layer containing additives, the base material 24 can be obtained by peeling off the coating film from the support after cast molding. The base material 24 is a plate-like base material in which a transparent resin layer such as an overcoat layer containing an additive, a curable resin, etc. is laminated on a support such as a support made of a transparent inorganic material or a support made of resin. In some cases, the substrate 24 can be obtained by, for example, casting and then not removing the coating.

Examples of the support include a glass plate, a steel belt, a steel drum, and a support made of transparent resin (eg, polyester film, cyclic olefin resin film).

Further, by a method of coating an optical member such as a transparent inorganic material or a transparent resin with the above resin composition and drying the solvent, or a method of coating the above curable composition, curing and drying, and the like, the A transparent resin layer can also be formed on the substrate.

When the substrate is a prismatic substrate comprising a transparent resin layer containing additives, it can be obtained by melt molding.

The amount of residual solvent in the base material obtained by the above method should be as small as possible. Specifically, the amount of residual solvent is preferably 3% by mass or less, more preferably 1% by mass or less, and still more preferably 0.5% by mass with respect to 100% by mass of the transparent resin layer or transparent resin substrate. It is below. When the amount of residual solvent is within the above range, it is possible to easily obtain a transparent resin layer and a transparent resin substrate which are resistant to deformation and change in properties and which can easily exhibit desired functions.

[Additive]
The base material 24 may contain additives such as antioxidants, light stabilizers, fluorescence quenchers, and ultraviolet absorbers within limits that do not impair the effects of the present invention. These additives may be used individually by 1 type, and may be used 2 or more types.

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.

Examples of the ultraviolet absorber include azomethine compounds, indole compounds, triazole compounds, triazine compounds, oxazole compounds, merocyanine compounds, cyanine compounds, naphthalimide compounds, oxadiazole compounds, and oxazine compounds. compound, oxazolidine-based compound, naphthalic acid-based compound, styryl-based compound, anthracene-based compound, cyclic carbonyl-based compound, and the like.

The ultraviolet absorber preferably has a maximum absorption wavelength in the range of 350 nm or more and 410 nm or less, more preferably 350 nm or more and 405 nm or less, and still more preferably 360 nm or more and 400 nm or less. By having the maximum absorption wavelength within the above range, an optical member with more excellent visibility correction can be easily obtained. Moreover, the absorption maximum wavelength can be measured using a solution in which an ultraviolet absorber is dissolved in dichloromethane.

[Dielectric multilayer film]
In the optical member according to the present invention, the reflective layer forming the reflective surface may be a dielectric multilayer film. A plurality of dielectric multilayer films may be provided. For example, an optical member 31 shown in FIG. 5A has a dielectric multilayer film 36a as a reflective layer forming a reflective surface 32, and a dielectric multilayer film 36b on the other surface of a substrate 35. As shown in FIG. The optical member 31 may have the dielectric multilayer film 36a only on the surface forming the reflecting surface of the substrate 35 . The optical member 31 preferably has the dielectric multilayer films 36a and 36b on both sides of the base material from the viewpoint of suppressing the warp. is less than 5.0 μm in absolute value. It is more preferably less than 4.0 μm, even more preferably less than 3.0 μm, even more preferably less than 2.0 μm, particularly preferably less than 1.5 μm, and most preferably less than 1.0 μm. When the absolute value of the difference in the total physical thickness of the dielectric multilayer film 36a and the dielectric multilayer film 36b is 0.1 μm or more and less than 5.0 μm, the dielectric multilayer film on one side is reduced in order to suppress warpage. It is preferable that the temperature during the formation and the temperature during the formation of the dielectric multilayer film on the other surface be different in the range of about 10.degree. C. to about 80.degree.

Like the optical member 41a shown in FIG. 5B, the dielectric multilayer film 46a may constitute the reflecting surface 42 of the prism-shaped substrate 45. As shown in FIG. Further, the light entrance surface 43 may be formed by the dielectric multilayer film 46b, and the light exit surface 44 may be formed by the dielectric multilayer film 46c. As shown in FIGS. 6A and 6B, the light L incident from the light incident surface 43 of the optical member 41 a is transmitted through the light incident surface 43 and reflected by the reflecting surface 42 . Reflected light L<b>1 reflected by the reflecting surface 42 is transmitted through the light emitting surface 44 and emitted from the optical member 41 . Also, the transmitted light L2 that is not reflected by the reflecting surface 42 is transmitted through the reflecting surface 42 and emitted from the optical member 41 . The optical member according to the present invention may be formed from a plurality of substrates 45 as shown in FIG. 5C, 5D or 5E, or the substrate 45 may have a curved surface as shown in FIG. 5F.

The dielectric multilayer film can be composed of, for example, a high refractive index material layer, a low refractive index material layer, a medium refractive index material layer, and the like.

Examples of the material forming the high refractive index material layer include materials having a refractive index of 2.0 or more, and materials having a refractive index of 2.0 or more and 3.6 or less are usually selected. Note that the refractive index represents a value for light with a wavelength of 550 nm.

Materials constituting the high refractive index material layer include, for example, titanium oxide, zirconium oxide, tantalum oxide, niobium oxide, lanthanum oxide, zinc oxide, zinc sulfide, barium titanate, silicon, and the like. Titanium oxide, niobium oxide, hafnium oxide, tin oxide, cerium oxide, etc., contained in an amount of, for example, more than 0% by mass and not more than 10% by mass with respect to the main component, titanium oxide, zirconium oxide, etc. in resins such as the above transparent resins, Examples thereof include those in which tantalum oxide, niobium oxide, lanthanum oxide, zinc oxide, zinc sulfide, barium titanate, silicon, or the like is dispersed.

Examples of the material forming the low refractive index material layer include materials with a refractive index of less than 1.6, and materials with a refractive index of 1.2 or more and less than 1.6 are usually selected. Examples of such materials include silica, lanthanum fluoride, magnesium fluoride, and sodium aluminum hexafluoride. In addition, silica, lanthanum fluoride, magnesium fluoride, sodium aluminum hexafluoride, etc. are dispersed in the transparent resin.

Examples of the material forming the medium refractive index material layer include materials having a refractive index of 1.6 or more and less than 2.0. Examples of such materials include aluminum oxide, bismuth oxide, europium oxide, yttrium oxide, ytterbium oxide, samarium oxide, indium oxide, magnesium oxide, and molybdenum oxide. Further, a mixture of these materials and a material constituting the high refractive index material layer, a material constituting the low refractive index material layer, a material constituting the high refractive index material layer and the low refractive index material layer and materials obtained by dispersing these materials in a resin such as the above-mentioned transparent resin.

The dielectric multilayer film may have a metal layer or a semiconductor layer with a thickness of about 1 nm to 100 nm. Materials constituting these layers include materials having a refractive index of about 0.1 to 5.0. Such materials include gold, silver, copper, zinc, aluminum, tungsten, titanium, magnesium, nickel, silicon, silicon hydride, germanium, and the like.

The method for forming the dielectric multilayer film is not particularly limited as long as the dielectric multilayer film is formed by stacking these material layers. For example, a dielectric layer in which a high refractive index material layer and a low refractive index material layer are alternately laminated directly on the base material by a CVD method, a sputtering method, a vacuum deposition method, an ion-assisted deposition method, an ion plating method, or the like. A dielectric multilayer film can be formed by alternately laminating a high refractive index material layer, a medium refractive index material layer, and a low refractive index material layer. When laminating a layer containing a transparent resin, it can be formed by melt molding, cast molding, or the like, preferably by spin coating, dip coating, slit coating, gravure coating, or the like, in the same manner as in the molding method of the substrate.

Among these, the sputtering method, the ion-assisted vapor deposition method, or the ion plating method is preferable from the viewpoints of adhesiveness to the base material and little change in the optical properties of the dielectric multilayer film due to humidity.

For example, the apparatus capable of performing the ion-assisted deposition includes the SYRUSpro series manufactured by Buehler Leybold Optics, the OTFC series manufactured by Optorun Co., Ltd., the MIC series and EPD series manufactured by Shincron Co., Ltd., and the VCD manufactured by ShinMaywa Industries, Ltd. series, Sapio series manufactured by Showa Shinku Co., Ltd., and the like.

In the ion-assisted vapor deposition, it is preferable to control the film formation rate of the vapor deposition with a crystal oscillator, and control the optical film thickness of each layer of the dielectric multilayer film with an optical monitor that estimates from the reflection intensity. When forming a layer with a physical thickness of 60 nm or less, it is preferable to control the film thickness based on the integrated value of the film formation rate of the crystal resonator. By controlling the film thickness based on the integrated value of the film formation rate of the crystal oscillator, it is possible to reduce the deviation of the optical film thickness control by the optical monitor.

The dielectric multilayer film is preferably formed at a temperature of 90° C. or higher. By setting the temperature to 90° C. or higher, when the obtained optical member is heated to 90° C., the occurrence of film peeling, breakage and cracking of the obtained dielectric multilayer film is reduced. From the viewpoint of improving the heat resistance temperature of the optical member, the formation temperature of the dielectric multilayer film is more preferably 120° C. or higher.

When the dielectric multilayer film is formed by vapor deposition, the vapor deposition starting vacuum degree is preferably 0.01 Pa or less, more preferably 0.005 Pa or less, and even more preferably 0.001 Pa or less. By increasing the degree of vacuum at the start of vapor deposition to a higher vacuum, it becomes possible to lower the moisture content in the obtained dielectric multilayer film, thereby reducing the phenomenon in which the optical properties of the obtained optical member change according to humidity. can. When the dielectric multilayer film is formed by the ion-assisted vapor deposition, the degree of vacuum during the formation of the dielectric multilayer film is preferably 0.05 Pa or less. By setting the viscosity to 0.05 Pa or less, the resulting dielectric multilayer film has good smoothness and an optical member with low haze can be obtained.

Further, the gas introduced into the ion gun, which is an ion supply device in the ion-assisted deposition, is preferably oxygen gas or a mixed gas of oxygen gas and rare gas. By using an oxygen gas or a mixed gas of an oxygen gas and a rare gas, it is possible to obtain a dielectric multilayer film having low absorption, good smoothness, and low crystallinity.

By appropriately setting the structure of the dielectric multilayer film, specifically, the material types constituting the high refractive index material layer, the medium refractive index material layer, the low refractive index material layer, etc., the high refractive index material layer, The optical member according to the present invention can be obtained by appropriately selecting the thickness of each layer such as the medium refractive index material layer and the low refractive index material layer, the order of lamination, the number of lamination, and the like.

[Reflection band]
The above dielectric multilayer film forms a reflection band by optical interference by appropriately setting the film thickness of each laminated layer. Here, the reflection band means a wavelength band in which the reflectance is 80% or more when the light is incident at an angle of 45° from the surface on which the dielectric multilayer film is formed. The optical member of the present invention has a reflecting surface having a reflection band with a reflectance of 80% or more in the wavelength region in order to efficiently deliver the visible light wavelength region of 400 nm or more and 640 nm or less to the sensor. In order to deliver visible light to the sensor more efficiently, the reflectance is 85% or more, more preferably 90% or more. In addition, in order to prevent near-infrared wavelength regions from 700 nm to 1150 nm in which human eyes have low visibility, which cause noise and ghost, from entering the sensor, there is no reflection band in the above wavelength regions. The reflectance in the wavelength range of 700 nm or more and 1150 nm or less is 8% or less, 6% or less, more preferably 4% or less from the viewpoint of further noise reduction.

[Other functional films]
In the optical member according to the present invention, the surface of the substrate opposite to the surface provided with the dielectric multilayer film is provided between the substrate and the dielectric multilayer film, as long as the effects of the present invention are not impaired. Or, on the surface of the dielectric multilayer film opposite to the surface on which the base material is provided, the surface hardness of the base material or the dielectric multilayer film is improved, chemical resistance is improved, antistatic, scratch removal, etc. For this purpose, it may have a functional film such as an antireflection layer, a hard coat film, an antistatic film, or the like. The optical member according to the present invention may contain one layer of the functional film, or may contain two or more layers. When the optical member according to the present invention contains two or more layers of the functional film, it may contain two or more similar layers or two or more different layers.

The method for laminating the functional film is not particularly limited, but a coating agent such as an antireflection agent, a hard coating agent, and an antistatic agent is applied to the substrate or the dielectric multilayer film in the same manner as described above by melt molding or casting. A molding method and the like can be mentioned. It can also be produced by applying a curable composition containing the coating agent and the like onto the base material and the dielectric multilayer film using a bar coater or the like, and then curing the composition by ultraviolet irradiation or the like.

Examples of the coating agent include ultraviolet (UV)/electron beam (EB) curable resins and thermosetting resins. Specifically, vinyl compounds, urethane, urethane acrylate, acrylate, epoxy and epoxy acrylate resins. 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.

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

The mixing ratio of the polymerization initiator in the curable composition is preferably 0.1% by mass or more and 10% by mass or less, more preferably 0.5% by mass when the total amount of the curable composition is 100% by mass. % by mass or more and 10% by mass or less, particularly preferably 1% by mass or less and 5% by mass or less. When the blending ratio of the polymerization initiator is in the above range, the resulting curable composition has excellent curing characteristics and handleability, and the functional film such as an antireflection layer, a hard coat film, and an antistatic film having a desired hardness. can be easily obtained.

An organic solvent may be added to the curable composition, and known solvents can be used as the organic solvent. 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, Esters such as propylene 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 - amides such as methylpyrrolidone. These solvents may be used individually by 1 type, and may be used 2 or more types.

The thickness of the functional film is preferably 0.9 μm or more and 30 μm or less, more preferably 0.9 μm or more and 20 μm or less, and particularly preferably 0.9 μm or more and 5 μm or less.

For the purpose of increasing the adhesion between the substrate and the functional film or the dielectric multilayer film and the adhesion between the functional film and the dielectric multilayer film, the substrate, the functional film or the dielectric multilayer film The surface may be subjected to surface treatment such as corona treatment, plasma treatment, and vacuum ultraviolet treatment.

[Light shielding film]
Further, the optical member according to the present invention may have a light shielding film on the outermost layer or part of the layer. For example, an optical member 51 in FIG. 7A has a light shielding film 52 on the surface of a substrate 53 . Further, the optical member 61 of FIG. 7B has a light shielding film 62a and a light shielding film 62b on the light incident surface and the light exit surface of the substrate 63. As shown in FIG. By having the light-shielding film in this way, in the solid-state imaging device or the camera module including the optical member 51 or the optical member 61, it is possible to suppress the light reflected by the frame or the lens from entering the sensor, and the ghost image is suppressed. can be obtained easily.

Materials for forming the light-shielding film include resin materials such as thermosetting resins, ultraviolet-curing resins, and thermoplastic resins; metal materials such as chromium, molybdenum, tungsten, iron, nickel, titanium, and chromium; and oxides of the above metal materials. , carbon materials such as graphite, carbon nanotubes, and fullerenes, absorption materials composed of one or more pigments, and one or more dyes. Among these, it is preferable to contain an ultraviolet curable resin from the viewpoint of easiness of shape control.

The thickness of the light shielding film is preferably 0.1 μm or more and 10 μm or less. If the thickness of the light shielding film is less than 0.1 μm, it tends to be difficult to obtain a sufficient optical density (OD value), and if it exceeds 10 μm, the influence of diffraction and reflection on the end face of the light shielding film is large. tend to become The thickness is preferably 0.5 μm or more and 4.0 μm or less.

The light shielding film provided on the optical member according to the present invention may be provided at one location or at a plurality of locations. Here, regarding the number of light-shielding films, it is assumed that continuous zones form one light-shielding film, and having a plurality of light-shielding films means having a plurality of discontinuous light-shielding films.

The light-shielding film preferably has an OD value of 3.0 or more, more preferably 4.0 or more, in terms of total light transmittance in a D65 light source (a standard light source defined by the International Commission for Certification (CIE)). If the OD value is within the above range, stray light can be sufficiently shielded.

A method for forming the light-shielding film is not particularly limited, and examples thereof include a coating method, a sputtering method, a vacuum deposition method, a screen printing method, and the like. The coating methods include spin coating, bar coating, dip coating, casting, spray coating, bead coating, wire bar coating, blade coating, roller coating, curtain coating, slit die coating, A gravure coating method, a slit reverse coating method, a micro gravure method, a comma coating method, and the like can be mentioned. Application in these methods may be performed in multiple steps.

The light shielding film may cooperate with a plurality of light shielding films to form a Fresnel zone plate or a mosaic mask. The optical member that constitutes the Fresnel zone plate can be used as a substitute for a lens, and the obtained solid-state imaging device, camera module, sensor module, etc. can be made thinner, which is preferable. The light-shielding film that constitutes the mosaic mask is preferable because it can eliminate the need for a lens, and image data with which the focal length can be changed can be obtained by computationally processing the obtained image.

The optical member according to the present invention may have uneven portions at positions not involved in the optical path. FIG. 8A shows an example in which rectangular parallelepiped protrusions 72 a and 72 b are provided on both side surfaces of the optical member 71 . Note that FIG. 8B is a top view of the optical member 71 seen from a direction perpendicular to the light incident surface. FIG. 8C is a bottom view of the optical member 71 viewed from a direction perpendicular to the reflecting surface. In a camera module equipped with an optical member according to the present invention, if the incident angle of light is shifted due to displacement of the optical member, the optical path of light reaching the sensor may be distorted. From the viewpoint that the angle of the optical member can be fixed based on the unevenness at a position that does not participate in the optical path, the optical member according to the present invention preferably has unevenness, and more preferably has convexities with ridges. Also, the uneven portion may be a recess.

The optical member according to the present invention is thin, has excellent visibility correction characteristics, and excels in cutting characteristics in the near-infrared band even when incident light is at a high angle. Therefore, it is useful for visibility correction of solid-state imaging devices such as solid-state imaging devices, camera modules, and sensors that are compatible with high-angle incidence.

[Details of Embodiment of Camera Module]
A camera module 101 a shown in FIG. 9A includes the optical member 1 described above, and the optical member 1 includes a reflecting surface 2 . The camera module 101a further comprises a lens 102, an optical filter 103a and an optical sensor 104a. A camera module 101 b shown in FIG. 9B includes the optical member 11 described above, and the optical member 11 includes a reflecting surface 12 . Also, the camera module according to the present invention may not have an optical filter between the lens and the optical sensor. For example, in the camera module 101c of FIG. 9C, the optical filter 103a is not installed between the lens 102 and the optical sensor 104a, and the cover glass 107 is installed on the optical path before the light enters the optical member 1.

Light incident on the camera module 101a shown in FIG. 9A is reflected by the reflecting surface 2, passes through the lens 102, and is received by the optical sensor 104a. Lens 102 may be single or multiple. Also, the lens 102 is appropriately set to be a convex lens, a concave lens, or the like according to the zoom performance of the camera module 101a.

The camera module 101a can secure a sufficient optical path length by using the reflecting surface 2 to change the optical path of light incident on the optical member 1 . Therefore, multiple lenses 102 can be incorporated in the optical path. The camera module 101a can have a zoom function or the like by means of the lens 102. FIG. In addition, the camera module 101a suppresses reflection of light in the wavelength region of 700 nm or more and 1150 nm or less, to which the silicon photodiode has high sensitivity, by the optical characteristics of the reflecting surface 2, and suppresses reflection of light in the wavelength region of 700 nm or more and 1150 nm or less in the optical sensor 104a. can interfere with the perception of As a result, the camera module 101a has good luminosity correction for making red color look natural to the human eye. Furthermore, the camera module 101a can eliminate the optical filter that shields near-infrared light from its configuration, and suppresses the occurrence of image defects such as ghosts caused by reflected light that occur when the above optical filter is used. be able to.

A camera module 101d shown in FIG. 9D includes a lens 102, an optical member 1 arranged in front of the lens 102 in the optical path, and an optical member 1 arranged behind the lens 102 in the optical path. In addition, the camera module 101d includes two optical members 1, and further includes a periscope-shaped optical system storage unit 108 in which the two optical members 1 are arranged such that the optical paths are substantially perpendicular. By providing the periscope-shaped optical system storage unit 108, the light incident surface and the sensor surface are parallel, so the sensor width is not limited by the thickness of the camera module, and a sensor with a larger area is possible. It is preferable. Since the camera module 101d having such a configuration can secure a long optical path length by bending the optical path twice, it is possible to realize high performance optical telephoto function and reduction in thickness. A lens 102 or a lens substituting planar optical element 106 may be provided between one optical member 1 and the other optical member 1 . Moreover, although not shown in FIG. 9D, the camera module 101d may include an optical filter and may include a plurality of optical system storage units.

A camera module 101e shown in FIG. 9E includes an absorber 105 that absorbs light in a specific wavelength range. The absorber 105 is provided on the optical path of the light that has entered the optical member 1 and has passed through the reflecting surface 2 without being reflected. As the optical characteristics of the absorber 105, the average reflectance for non-polarized light incident on the absorber 105 at 5° from the vertical direction is preferably 10% or less in the wavelength region of 700 nm or more and 1150 nm or less, and is 5% or less. and more preferred.

For the absorber 105, for example, a transparent resin containing a near-infrared light absorbing dye having steep absorption characteristics can be used. As the near-infrared absorption dye, for example, a metal complex compound, dye, or pigment that acts as a dye that absorbs near-infrared light can be used. dyes, squarylium dyes, croconium dyes, dithiol metal complex compounds, and the like.

A camera module 101f shown in FIG. 9F does not include an optical filter, and an optical sensor 104b is provided on the optical path of light transmitted through the reflecting surface 2 without being reflected. Optical sensor 104b may be an ambient light sensor. A camera module having such a configuration can receive light that has passed through the reflecting surface 2 without being reflected, and can sense the brightness around the camera module 101f. As a result, it is possible to install the light receiving portion for solid-state imaging and the light receiving portion for ambient light in one module, and it is possible to provide a camera module with excellent design. The optical sensor 104b included in the camera module 101f may be a near-infrared sensor. This near-infrared sensor can capture night vision and measure the distance to an object.

A camera module according to the present invention may include an optical filter 103b in front of the optical sensor 104b, like the camera module 101g of FIG. 9G. Also, an optical filter 103a can be provided in front of the optical sensor 104a. The camera module 101g includes at least one of an optical filter 103a and an optical filter 103b.

A camera module according to the present invention, like a camera module 101h in FIG. 9H, is a lens substitute having a role as a lens such as a Fresnel zone plate, a Fresnel lens, a metalens, a mosaic mask, etc., between an optical sensor 104a and an optical filter 103a. A planar optical element 106 may be provided. Alternatively, as in a camera module 101i including the optical member 1 in FIG. 9I, light may be reflected by the reflective surface 2 instead of entering through the light incident surface of the optical member 1 .

A camera module according to the present invention may include the optical member 11 in a rotatable state, like the camera module 101j of FIG. 9J. Since the light is guided to the optical sensor 104a when the optical member 11 is fixed at an appropriate angle and is not guided at other angles, a shutter function using the optical member 11 can be provided.

A camera module according to the present invention has two optical members 1, like a camera module 101k shown in FIG. A lens 102 may be arranged.

The camera module according to the present invention preferably does not have an optical filter in front of the optical sensor 104a, like the camera module 101l in FIG. 9L, from the viewpoint of noise and ghost reduction due to near-infrared rays. Furthermore, it is more preferable to have a cover glass 107 having a near-infrared cut performance on the front surface of the optical member 11 . The cover glass 107 is not limited as long as it does not impair the effect of the present invention, which transmits light of a specific wavelength. Become. A transparent inorganic material is preferable from the viewpoint of scratch resistance. The cover glass 107 may have an antireflection layer and a dielectric multilayer film from the viewpoint of improving the sensitivity of the optical sensor and reducing image defects. From the viewpoint of reducing image defects caused by near-infrared rays even when a light source that strongly emits near-infrared rays is incident on the optical sensor, the cover glass 107 preferably has a dielectric multilayer film having a near-infrared cutting function. It is preferable that the average transmittance of light incident from the vertical direction of 107 is 10% or less at a wavelength of 800 nm or more and 1150 nm or less. As such a dielectric multilayer film, for example, design (VII) in Table 7, which will be described later, can be cited.

The camera module according to the present invention further includes a focus adjustment mechanism, a phase detection mechanism, a distance measurement mechanism, an iris authentication mechanism, a vein authentication mechanism, a face authentication mechanism, a blood flow meter, an oxidized or reduced hemoglobin meter, and a vegetation index meter. etc. may be provided. Such a camera module can be suitably used for devices that output images and information as electrical signals. Moreover, such a camera module may be configured to have a lens or may be configured to have no lens. Moreover, from the viewpoint of obtaining an image with a short optical path and less aberration, it is preferable to use a reflective lens as the lens.

Photoelectric conversion elements such as silicon, avalanche diodes, black silicon, InGaAs, selenium, and organic photoelectric conversion films that convert light of a specific wavelength into electric charges are used as members constituting the solid-state imaging device.

[Black Silicon]
Black silicon may be used for the light receiving portion of the solid-state imaging device using this filter. Black silicon can be obtained, for example, by irradiating a silicon wafer with a laser under a specific atmosphere to form minute spikes on the silicon surface. When black silicon is used, the light receiving sensitivity in the near-infrared band becomes higher than in the case of using a silicon photodiode. Therefore, black silicon is preferably used for imaging devices using near-infrared rays. Commercially available CMOS products using black silicon include XQE series manufactured by SiOnyx.

[Other embodiments]
The embodiments disclosed this time are examples and do not limit the configuration of the present invention. Therefore, in the above embodiment, the components of each part of the above embodiment can be omitted, replaced, or added based on the description of the present specification and common general technical knowledge, and all of them are understood to fall within the scope of the present invention. should.

[Example]
EXAMPLES The present invention will be described in more detail below based on examples, but the present invention is by no means limited to these examples. In addition, "parts" means "parts by mass" unless otherwise specified. In addition, the method for measuring each physical property value and the method for evaluating physical properties are as follows.

[Molecular weight]
The molecular weight of the resin is determined using a GPC apparatus manufactured by Tosoh Corporation (HLC-8220, column: TSKgelα-M, developing solvent: THF), and the weight average molecular weight (Mw) and number average molecular weight (Mn) in terms of standard polystyrene. It was measured.

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

[Resin Synthesis Example 1]
8-methyl-8-methoxycarbonyltetracyclo[4.4.0.1 ^2,5 . 1 ^7,10 ]dodeca-3-ene (hereinafter also referred to as “DNM”) 100 parts, 1-hexene (molecular weight modifier) 18 parts and toluene (solvent for ring-opening polymerization reaction) 300 parts were replaced with nitrogen. A vessel was charged and the solution was heated to 80°C. Next, 0.2 part of a toluene solution of triethylaluminum (0.6 mol/liter) and 0.2 part of a toluene solution of methanol-modified tungsten hexachloride (concentration: 0.025 mol/liter) were added as polymerization catalysts to the solution in the reaction vessel. 9 parts were added, and this solution was heated and stirred at 80° C. for 3 hours to carry out ring-opening polymerization reaction to obtain a ring-opening polymer solution. The polymerization conversion rate in this polymerization reaction was 97%.

An autoclave was charged with 1,000 parts of the ring-opened polymer solution thus obtained, and 0.12 part of RuHCl(CO)[P(C ₆ H ₅ ) ₃ ] ₃ was added to the ring-opened polymer solution. Then, under the conditions of a hydrogen gas pressure of 100 kg/cm ² and a reaction temperature of 165° C., a hydrogenation reaction was carried out by heating and stirring for 3 hours. After cooling the resulting reaction solution (hydrogenated polymer solution), hydrogen gas was released. This reaction solution was poured into a large amount of methanol to separate and recover a solidified 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.

[Base material A]
100 parts of Resin A obtained in Resin Synthesis Example 1 and methylene chloride were added to a container to prepare a solution having a resin concentration of 20% by weight. 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 at 140° C. under reduced pressure for 2 hours to obtain a substrate A consisting of a transparent resin substrate having a thickness of 0.1 mm, a length of 60 mm and a width of 60 mm.

[Base material B]
100 parts of a cycloolefin resin (ZEONEX, Nippon Zeon Co., Ltd.) and cyclohexane were added to a container to prepare a solution having a resin concentration of 20% by weight. 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 at 150° C. under reduced pressure for 2 hours to obtain a substrate B made of a transparent resin having a thickness of 0.1 mm, a length of 60 mm and a width of 60 mm.

[Base material C]
A glass substrate (D263T eco, manufactured by Shot Japan Co., Ltd.) having a thickness of 0.1 mm was used as the substrate C.

[Base material D]
100 parts of Resin A obtained in Resin Synthesis Example 1, 0.04 parts of Compound A, 0.08 parts of Compound D described later, and methylene chloride were added to a container to prepare a solution having a resin concentration of 20% by weight. . 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 at 140° C. under reduced pressure for 2 hours to obtain a substrate D made of a transparent resin having a thickness of 0.1 mm, a length of 60 mm and a width of 60 mm.

[Base material E]
A triangular prism-shaped TECHSPEC (registered trademark) synthetic quartz right angle prism (manufactured by Edmund Optics Japan Co., Ltd.) having a length L of 5.0 mm, a width of 5.0 mm, and a height of 5.0 mm shown in FIG.

[Injection molding substrate]
[Base material F]
Cycloolefin resin (ZEONEX T62R manufactured by Nippon Zeon Co., Ltd.) is used as an injection molding machine by FANUC ROBOSHOT S-2000i30B, cylinder temperature 320 ° C., mold temperature 160 ° C., injection speed 20 mm / s, pressure holding time 6 A cycloolefin resin rectangular prism having a length L of 5.0 mm, a width W of 5.0 mm, and a height H of 5.0 mm was obtained at a cycle time of 20 minutes. The obtained rectangular prism was used as a substrate F.

[Base material G]
The resin A obtained in Resin Synthesis Example 1 was subjected to the same injection conditions as those for the base material F, with a length L of 5.0 mm, a width of 5.0 mm, and a height of 5.0 mm shown in FIG. Obtained. The rectangular prism thus obtained was used as a substrate G.

[Base material H]
Resin A obtained in Resin Synthesis Example 1 was preheated at 100 ° C. for 1 hour using a microwave molding apparatus, then subjected to microwave irradiation intensity of 3 kW, temperature increase rate of 5 ° C./min, target At a temperature of 180° C. and a temperature holding time of 10 minutes, a rectangular prism made of cycloolefin resin having a length L of 5.0 mm, a width of 5.0 mm and a height of 5.0 mm as shown in FIG. 4 was obtained. Similarly, a 1.0 mm long, 1.0 mm wide, and 1.0 mm deep cube A made of resin A was formed. After applying methylene chloride to one surface of the obtained cube A, two cubes were press-bonded to the cycloolefin resin rectangular prism as shown in FIG. Substrate H was a right-angle prism having an uneven portion at a position not affected by .

[Base material I]
₄₁ parts of _P2O5 , 5 parts of _Al2O3 , 24 parts of _Na2O , 6 parts of _MgF2 , 6 parts _of CaO, 12 parts of BaO, and 0.035 parts of CuO were weighed and mixed. . It was placed in a platinum crucible and heated and melted at a temperature of 1000°C. After sufficiently stirring and fining, it was cast into a mold to obtain a copper phosphate glass rectangular prism having a length of 5.0 mm, a width of 5.0 mm, and a height of 5.0 mm as shown in FIG. The rectangular prism thus obtained was used as a substrate I.

[Base material J]
The resin A obtained in Resin Synthesis Example 1 and the compound A described later were injection-molded under the conditions of length L 5.0 mm, width W 5.0 mm, and height H 5.0 mm shown in FIG. Obtained. The obtained rectangular prism was used as a substrate J.

[Coating film A]
After applying the following resin composition (1) to the surface of the substrate shown in Table 8 below by spin coating, it was heated on a hot plate at 80° C. for 2 minutes to evaporate and remove the solvent to form a cured layer. At this time, the coating conditions of the spin coater were adjusted so that the film thickness of the cured layer was about 0.8 μm.
Resin composition (1): isocyanuric acid ethylene oxide-modified triacrylate (trade name: Aronix M-315, manufactured by Toagosei 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: IRGACURE 184, manufactured by Chiba Specialty Chemical Co., Ltd.) and San-Aid SI-110 main agent (Sanshin Kagaku Kogyo Co., Ltd.) was mixed, dissolved in propylene glycol monomethyl ether acetate so that the solid content concentration was 50% by mass, and then filtered through a Millipore filter having a pore size of 0.2 μm.

Next, 100 parts of Resin A obtained in Resin Synthesis Example 1, 0.4 parts of Compound A described later, 0.8 parts of Compound D described later, and methylene chloride were added to a container to obtain a solution having a resin concentration of 15% by mass. (A) was obtained. On the cured layer, the solution (A) is applied with a spin coater so that the film thickness after drying is 10 μm, heated on a hot plate at 80 ° C. for 30 minutes, and the solvent is volatilized to remove the transparent resin. formed a layer. Next, the glass plate side was exposed using a UV conveyor type exposure machine (exposure amount: 500 mJ/cm ² , illuminance: 200 mW), and then baked in an oven at 210° C. for 5 minutes to obtain a coating film A.

[Coating film B]
Coating film B was obtained in the same procedure except that 0.4 parts of compound A and 0.8 parts of compound D in coating film A were replaced with 0.8 parts of compound B described later.

[Coating film C]
The same procedure except that 0.2 parts of compound A instead of 0.4 parts of compound A and 0.8 parts of compound D in coating film A, 0.68 parts of compound C and 0.8 parts of compound D described later were used to obtain a coating film C.

[Coating film D]
Coating film D was obtained in the same procedure except that 0.4 parts of compound A and 0.8 parts of compound D in coating film A were replaced with 0.2 parts of compound A.

[Coating film E]
Resin composition (1) was applied using a spin coater so that the film thickness after drying was 0.002 mm, and then dried at 80° C. for 3 hours using an inert oven (inert oven DN410I manufactured by Yamato Scientific Co., Ltd.). dried for a minute. A resin near-infrared cut filter Lumicle UCF (Lumicle 100-132) is pressed onto the coated film with a stress of 300 g/cm2, and then a UV conveyor (manufactured by Eye Graphics Co., Ltd., eye ultraviolet curing device, model US2-X0405 60 Hz), a metal halide lamp illuminance of 270 mW/cm ² and an exposure amount of 500 mJ/cm ² for UV curing to obtain a coating film E.

[Coating film F]
100 parts of Resin A obtained in Resin Synthesis Example 1, 0.16 parts of Compound B described later, and methylene chloride were added to a container to prepare a solution having a resin concentration of 20% by weight. 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 at 140° C. under reduced pressure for 2 hours to obtain a transparent resin film having a thickness of 0.05 mm, a length of 60 mm and a width of 60 mm. Separately, the following resin composition (2) was applied to the substrate by spin coating, and then heated on a hot plate at 80° C. for 2 minutes to evaporate and remove the solvent to form a cured layer. At this time, the coating conditions of the spin coater were adjusted so that the film thickness of the cured layer was about 2 μm.
Resin composition (2): A composition containing 60 parts of tricyclodecanedimethanol acrylate, 40 parts of dipentaerythritol hexaacrylate, 5 parts of 1-hydroxycyclohexylphenyl ketone, and methyl ethyl ketone (used so that the solid content concentration is 30% by mass). thing.

After the above transparent resin film is crimped onto the applied cured layer with a load of 300 g/cm2, a UV conveyor (manufactured by Eye Graphics Co., Ltd., eye ultraviolet curing device, model US2-X0405 60 Hz) is used, and a metal halide lamp is used. UV curing was performed at an illuminance of 270 mW/cm ² and an exposure amount of 500 mJ/cm ² to obtain a coating film F.

[Coating film G]
Coating film G was obtained in the same procedure except that 0.04 parts of compound A and 0.14 parts of compound C and 0.16 parts of compound D were used instead of 0.16 parts of compound B in coating film F.

[Deposition A]
Using an ion-assisted vacuum deposition apparatus, a starting pressure of 0.0001 Pa, a deposition temperature of 120 ° C., a mixed gas of oxygen and argon as a supply gas to the ion gun, and a layer with a physical thickness of 60 nm or less is integrated with a crystal oscillator. Controlled by the film thickness, the ion current density per unit area (μA/cm2) was divided by the film formation rate (Å/sec) ^. A silica layer (SiO ₂ : the refractive index of light at 550 nm is 1.47) is formed while performing ion assist, and the ion current density per unit deposition rate/area is 10 μA·sec/Å·cm ² or more and 20 μA·sec/Å.・The design shown below, in which a titanium oxide layer (TiO ₂ : the refractive index of light at 550 nm is 2.48) is formed while performing ion assist of cm ² or less, and silica layers and titanium oxide layers are alternately laminated. The dielectric multilayer film of I) was provided.

[Deposition B]
A dielectric multilayer film was provided by the same procedure except that design (I) in vapor deposition A was changed to design (II) shown in Table 2.

[Deposition C]
A dielectric multilayer film was provided in the same procedure except that design (I) in vapor deposition A was changed to design (III) shown in Table 3.

[Deposition D]
A silica layer ( An amorphous silicon layer (α _- Si: H: A dielectric multilayer film of design (IV) shown in Table 4, in which H: refractive index 4.1) for light at 550 nm is alternately laminated.

[Deposition E]
A dielectric multilayer film was provided by the same procedure except that design (I) in vapor deposition A was changed to design (V) shown in Table 5.

[Deposition F]
Using an RF magnetron sputtering apparatus, Al was used as a vapor deposition source, and Al was formed as a vapor deposition film of 50 nm with an RF power of 300 W.

[Deposition G]
An RF magnetron sputtering apparatus was used, Ag was used as a vapor deposition source, and Ag was formed as a 100 nm vapor deposition film by forming a film with an RF power of 300 W.

[Deposition H]
A dielectric multilayer film was provided by the same procedure except that design (I) in vapor deposition A was changed to design (VI) shown in Table 6.

[Deposition I]
A dielectric multilayer film was provided in the same procedure except that design (I) in vapor deposition A was changed to design (VII) shown in Table 7.

[Light shielding film A]
An ultraviolet curable light-shielding ink (UltraPack UVK+180 manufactured by Marabu) was applied to the outer periphery of the optical member by screen printing to a width of 1 mm and a thickness of 10 μm. Using a UV conveyor (manufactured by Eye Graphics Co., Ltd., eye ultraviolet curing device, model US2-X0405, 60 Hz), UV curing was performed at a metal halide lamp illuminance of 100 mW / cm and an exposure amount of 200 mJ / cm to obtain a light shielding film A. .

[Compound A]
A compound A represented by the following chemical formula (A) was used as the compound. Compound A has a maximum absorption wavelength of 698 nm when dissolved in dichloromethane.

[Compound B]
A compound B represented by the following chemical formula (B) was used as the compound. Compound B has a maximum absorption wavelength in resin A of 1095 nm.

[Compound C]
A compound C represented by the following chemical formula (C) was used as the compound. Compound C has a maximum absorption wavelength of 738 nm when dissolved in dichloromethane.

<Ultraviolet absorber>
As a UV absorber, "BONASORB UA-3911" manufactured by Orient Chemical Industry Co., Ltd. was used as compound D. Compound D has a maximum absorption wavelength of 391 nm when dissolved in dichloromethane.

[Example 1]
The substrate A was prepared, and the dielectric multilayer film 36a of the optical member 31 shown in FIG. , the dielectric multilayer film 36b (hereinafter referred to as surface B in Examples 1 to 5 and Comparative Examples 1 and 2) was formed by vapor deposition A, thereby obtaining an optical member.

[Examples 2 to 5]
An optical member was obtained in the same manner as in Example 1, except that the optical member was produced using the substrate, vapor deposition method, and light-shielding film shown in Examples 2 to 5 in Table 8 below.

[Comparative Examples 1 and 2]
An optical member was obtained in the same manner as in Example 1, except that the optical member was produced using the substrate, vapor deposition method, and light-shielding film shown in Comparative Examples 1 and 2 in Table 8 below.

[Example 6]
The substrate E was prepared, and the dielectric multilayer film 46a (hereinafter referred to as the A surface in Examples 6 to 18 and Comparative Example 3) of the optical member 41a shown in FIG. The dielectric multilayer film 46b (hereinafter referred to as the B side in Examples 6 to 18 and Comparative Example 3) was formed by the vapor deposition A, and the dielectric multilayer film 46c (hereinafter referred to as Examples 6 to 18 and Comparative Example 3). ) was vapor-deposited in the vapor deposition A described above. Furthermore, the optical member was obtained by forming the light shielding film A on the B surface and the C surface.

[Example 7]
The substrate G is prepared, the coating film A is formed on the B surface, the A surface is vapor-deposited by the vapor deposition C, the B surface is vapor-deposited by the vapor deposition A, and the C surface is vapor-deposited by the vapor deposition A. got the parts.

[Examples 8 to 17, Comparative Example 3]
In the same manner as in Example 6 or Example 7, except that an optical member was produced using the substrate, light absorber, vapor deposition method, and light shielding film shown in Examples 8 to 17 and Comparative Example 3 in Table 8 below. , an optical member was obtained. In Examples 11 and 12, the optical member was produced on the assumption that the optical member is used as shown in FIG. 9I.

[Example 18]
An optical member was obtained in the same manner as in Example 17. Separately, vapor deposition I was provided on one surface of the substrate C to obtain a cover glass.

[Evaluation of optical properties]
The optical properties of the optical members produced in Examples 1 to 18 and Comparative Examples 1 to 3 were evaluated by the method shown in FIG. FIG. 10A shows a method for measuring the transmittance of an unpolarized light incident at 45° of an optical member. FIG. 10B is a method of measuring the reflectance of an unpolarized light incident at 45° on an optical member. FIG. 10C is a method of measuring the reflectance of an unpolarized light incident at 5° on an optical member. FIG. 10D shows a method for measuring the reflectance of an optical member made of a prismatic substrate for unpolarized light at 45° incidence. In Examples 11 and 12, it was assumed that an optical member was used as in the camera module shown in FIG. 9I, and the reflectance in FIG. 10D was defined as the spectral transmission efficiency. 10E shows a method for measuring the spectral transmission efficiency of the optical members in Examples 6 to 10, Examples 13 to 17, and Comparative Example 3. FIG. FIG. 10F shows a method of measuring 100% of the light amount used as a reference in spectral transmission efficiency measurement. 10G is a method for measuring spectral transmission efficiency through a cover glass in Example 18. FIG.

[Transmittance]
The transmittance of the optical member in each wavelength region was measured using a spectrophotometer (V-7200) manufactured by JASCO Corporation and an automatic absolute reflectance measurement unit (V-7030). Here, the transmittance of light incident at an angle of 45° from the direction perpendicular to the surface direction of the optical member is, as shown in FIG. Light L (P-polarized light and S-polarized light) was incident, and the light transmitted in the vertical direction was reflected by the mirror 202 and collected by the integrating sphere 201 for measurement. In addition, the average transmittance of the wavelength A-Bnm is measured by measuring the transmittance at each wavelength of 1 nm or more and B nm or less, and the total of the transmittances is the number of measured transmittances (wavelength range, BA + 1 ). A value calculated from the average of the S-polarized light transmittance and the P-polarized light transmittance was used as the transmittance of non-polarized light. For the maximum transmittance of wavelengths A to B nm, the transmittance at each wavelength from Anm to Bnm was measured in increments of 1 nm, and the maximum value of the transmittance was used.

[Reflectance]
The reflectance of the optical member in each wavelength region was measured using a spectrophotometer (V-7200) manufactured by JASCO Corporation and an automatic absolute reflectance measurement unit (V-7030). Here, the reflectance of a non-polarized light beam incident at an angle of 45° with respect to the direction perpendicular to the surface of the optical member is 45° with respect to the direction perpendicular to the specific surface of the optical member 11 as shown in FIG. The incident light L was measured by condensing the light reflected by the optical member 11 with the integrating sphere 201 via the mirror 202 . Similarly, the reflectance of a non-polarized light beam incident at an angle of 5° to the normal to the surface of the optical member is as shown in FIG. The light reflected by the incident unpolarized light was collected by the integrating sphere 201 via the mirror 202 to measure the light.

Similarly, when the optical member is not a flat plate, the reflectance of a non-polarized light beam incident at an angle of 45° with respect to the direction perpendicular to the surface of the optical member is 45° with respect to the direction perpendicular to the specific surface as shown in FIG. 10D. A light beam L incident at an angle of .degree.

The average reflectance at wavelengths A-B nm is obtained by measuring the reflectance at each wavelength of 1 nm or more and B nm or less, and the total reflectance is the number of measured reflectances (reflectance, B-A+1). It was calculated by the value obtained by dividing As for the maximum reflectance at wavelengths A to B nm, the reflectance was measured at each wavelength of 1 nm from An nm to B nm, and the maximum value of the reflectance was used.

[Spectral transmission efficiency]
In Examples 6 to 10, Examples 13 to 17, and Comparative Example 3, the spectral transmission efficiency T(λ) of the optical member is as shown in FIG. 10E when the light amount in FIG. Second, the light L was measured by collecting the light reflected by the reflecting surface after passing through the base material with the integrating sphere 201 via the mirror 202 . In Examples 11 and 12, it is assumed that an optical member such as the camera module shown in FIG. 9I is used, and the reflectance obtained with the arrangement of the optical member 1 shown in FIG. 10D is defined as the spectral transmission efficiency T(λ). . In Example 18, it is assumed that an optical member is used via a cover glass as in the camera modules shown in FIGS. 9C and 9L. was defined as the spectral transmission efficiency T(λ). For optical members having a light-shielding film, the portion inside the light-shielding film where no light-shielding film was provided was evaluated.
In addition, the average transmission efficiency of the wavelength A-B nm is obtained by measuring the spectral transmission efficiency at each wavelength of 1 nm or more and B nm or less, and calculating the sum of the spectral transmission efficiencies as the number of measured spectral transmission efficiencies (reflectance, Calculated by dividing by BA+1). Further, the maximum transmission efficiency at wavelengths AB nm was obtained by measuring the spectral transmission efficiency at each wavelength from An nm to B nm in increments of 1 nm, and using the maximum value of the spectral transmission efficiency.

[Noise amount evaluation]
[N / S sensitivity evaluation]
As an index for evaluating the amount of noise in an optical sensor equipped with an optical member, the ratio of noise N by near-infrared rays to signal S by visible light, and N/S sensitivity evaluation were performed. N/S sensitivity evaluation is the spectral transmission efficiency T (λ) of the optical member, and in the sensor pixel, the blue pixel sensitivity B (λ) by wavelength, the green pixel wavelength G (λ), and the red pixel wavelength sensitivity R It was calculated from (λ) by the following formula.
The signal intensity S was the sum of the calculated products of the transmittance of the optical filter for each wavelength of 1 nm and the sensitivity of the sensor pixel in the blue, green, and red pixel wavelength range from 380 nm to 780 nm. The noise intensity N was the sum of the calculated values of the product of the transmittance of the optical filter for each wavelength of 1 nm in the blue, green, and red pixel wavelength region from 781 nm to 1050 nm and the sensor pixel sensitivity. For the N/S sensitivity evaluation, a value obtained by dividing the noise intensity N by the signal intensity S using these calculated values of N and S was used as an index. Based on the description of Japanese Patent Laid-Open No. 2017-216678, the values shown in FIG. 11 were used as the wavelength sensitivity of each sensor pixel of blue, green, and red.

[Evaluation results of optical properties]
The optical properties of the optical members of Examples 1 to 18 and Comparative Examples 1 to 3, which were produced as shown in Table 8, were evaluated. The evaluation results are shown in Table 9.

From the results in Table 9 above, the optical members of Examples can reflect light of a specific wavelength and have low N/S sensitivities, so they are suitable as optical members according to the present invention. Further, the optical members of Comparative Examples 1 to 3 do not suppress the reflection of light in the wavelength region of 700 nm or more and 1150 nm or less. .

The optical member according to the present invention is particularly useful as an optical member constituting a camera module. The camera module according to the present invention is particularly useful for digital still cameras, mobile phone cameras, smartphone cameras, digital video cameras, PC cameras, surveillance cameras, automobile cameras, televisions, car navigation systems, personal digital assistants, personal computers, and video cameras. It is useful for games, portable game machines, fingerprint authentication systems, ambient light sensors, distance measurement sensors, iris authentication systems, face authentication systems, distance measurement cameras, digital music players, and the like.

L Light L1 Reflected light L2 Transmitted light 1, 11, 21, 31, 41a-e, 51, 61, 71 Optical member 2, 12, 22, 32, 42 Reflective surface 3, 43 Light incident surface 4, 44 Light exit surface 5 Prism 23 Reflective layers 24, 35, 45, 53, 63, 73 Base materials 36a, 36b, 46a, 46b, 46c Dielectric multilayer films 52, 62a, 62b Light shielding films 72a, 72b Projections 101a to l Camera module 102 Lens 103a , 103b optical filters 104a, 104b optical sensor 105 absorber 106 lens-substituting planar optical elements 107, 203 cover glass 108 optical system storage unit 201 integrating sphere 202 mirror

Claims (7)

Equipped with a reflective surface,
The average reflectance of non-polarized light rays incident at 45° perpendicular to the reflecting surface is 80% or more in the wavelength range of 400 nm or more and 640 nm or less and 8% or less in the wavelength range of 700 nm or more and 1150 nm or less,
A base material and a reflective layer that constitutes the reflective surface,
The base material contains a compound having an absorption maximum in a wavelength range of 680 nm or more and 1200 nm or less,
A prism having a triangular cross section with an apex angle of 70° or more and 120° or less,
the reflective surface is formed on a slope facing the apex angle of the prism;
The prism comprises a light incident surface through which light incident toward the reflecting surface is transmitted, and a light exit surface through which light reflected by the reflecting surface is transmitted,
The prism has an average transmission efficiency of 400 nm or more and 640 nm or less in a wavelength range of 400 nm or more and 640 nm or less for unpolarized light rays that are incident on the light entrance surface, reflected at an angle of 45° from the perpendicular to the reflection surface, and transmitted through the light exit surface. 72% or more at a wavelength of 600 nm, a transmittance of 66% or more at a wavelength of 600 nm, and a maximum transmission efficiency of 12% or less in a wavelength region of 700 nm or more and 1150 nm or less. 2. The optical member according to claim 1, wherein the maximum reflectance of non-polarized light incident on the reflecting surface at an angle of 45[deg.] is 20% or less in the wavelength range of 700 nm or more and 1150 nm or less. 3. The optical member according to claim 1, wherein the reflectance of non-polarized light incident on the reflecting surface at an angle of 45[deg.] from the vertical is 65% or more at a wavelength of 650 nm. A camera module comprising the optical member according to claim 1 . 5. The camera module of Claim 4 , further comprising an optical sensor. Equipped with an additional lens,
6. The camera module according to claim 5 , wherein no optical filter is provided between said lens and said optical sensor. 7. The camera module according to any one of claims 4 to 6, further comprising a periscope-shaped optical system housing unit.

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