JP5994686B2 - Optical glass - Google Patents

Description

  The present invention relates to an optical glass, and more particularly to an optical glass such as a cover glass and a near infrared cut filter.

  Optical glass such as near-infrared cut filter glass and cover glass is used for solid-state imaging devices such as CCD (Charge Coupled Device) and CMOS (Complementary Metal Oxide Semiconductor) used in digital still cameras. In recent years, optical glass with a thin plate thickness has been demanded from the demand for thin solid-state imaging device modules and digital still cameras mounted on mobile terminals such as mobile phones and smartphones.

  However, when the thickness of the optical glass is reduced, if bending stress acts on the optical glass, the crack will start from the chip and minute cracks that exist on the ridgeline of the glass (the boundary between the main surface and the side surface of the glass). There is a high possibility of damage.

  For this reason, it is proposed to chamfer the glass end face from the viewpoint of improving the bending strength of the glass (see Patent Document 1). This is to increase the bending strength of the glass by removing the scratches on the glass end face, which is the starting point of cracking, by chamfering. It has also been proposed to remove scratches on the surface of the glass plate by etching (see Patent Document 2).

JP 2000-169166 A JP 2010-168262 A

However, the chamfering process of the glass end face and the process of removing scratches on the glass surface deteriorate (decrease) the productivity of the optical glass. Moreover, a flaw may be formed in a glass end surface by chamfering. This is because glass chamfering is mechanically processed with a grinding wheel. That is, there is a possibility that unintentional scratches may be newly formed due to an impact during chamfering. In addition, if etching is performed while maintaining the main surface of the glass in order to remove scratches on the surface of the glass, uneven etching occurs on the main surface serving as the optical working surface, and the optical properties as optical glass deteriorate (decrease). )
The present invention has been made to solve the above problems, and an object of the present invention is to provide a highly reliable optical glass that is not easily damaged by an external force such as an impact.

The optical glass according to the present invention is an optical glass bonded to the casing so as to cover the opening of the casing, and is opposed to the first main surface on the side bonded to the casing and the first main surface. A glass substrate having a second main surface, and an optical thin film provided at least on the first main surface . The internal stress of the optical thin film provided on the first main surface is a tensile stress, and a stress of 5 MPa to 150 MPa acts on the optical glass in a direction that swells on the side opposite to the casing .

  According to the present invention, since the stress is applied to the optical glass in the direction in which it swells on the side opposite to the casing, it is possible to provide a highly reliable optical glass that is not easily damaged even when an external force such as an impact is applied. be able to.

It is sectional drawing of the optical glass which concerns on embodiment. It is sectional drawing which shows an example which used the optical glass which concerns on embodiment for an imaging device. It is explanatory drawing of the method of providing stress to the optical glass which concerns on embodiment.

  Hereinafter, the optical glass according to the embodiment will be described with reference to the drawings.

(Embodiment)
FIG. 1 is a cross-sectional view of an optical glass 100 according to an embodiment. As shown in FIG. 1, the optical glass 100 according to the present embodiment is used for, for example, a solid-state imaging device such as a digital still camera (for example, Charge Coupled Device (hereinafter, CCD) or Complementary Metal Oxide Semiconductor (CMOS)). Optical glass such as cover glass and near infrared cut filter. The optical glass 100 is provided on the glass substrate 110, the optical thin film 120 as an antireflection film provided on the surface 110A (translucent surface) of the glass substrate 110, and the back surface 110B (translucent surface) of the glass substrate 110. And an optical thin film 130 as a UVIR cut film (an ultraviolet shielding film and an infrared shielding film) for cutting ultraviolet (UV) rays and infrared (IR) rays.

  The cover glass is hermetically sealed to an alumina ceramic package or a resin package in which an LSI chip, which is a light receiving element of a solid-state image sensor, is housed, and not only protects the LSI chip but also efficiently transmits light to the light receiving surface. Therefore, high transmittance characteristics are required in the visible light region. The near-infrared cut filter is used as a color correction filter for correcting visibility, and is required to efficiently transmit a visible light region of 400 to 600 nm and to have excellent sharp cut characteristics in the vicinity of 700 nm.

  When the optical glass 100 is used by being bonded to another member, it is preferable to match the thermal expansion coefficients. Since the optical glass 100 used as such an optical glass is required to have high transmittance in the visible light region, an optical thin film 120 as an antireflection film is provided on the surface 110A of the glass substrate 110 on the light incident side. It has been.

(Glass substrate 110)
The glass substrate 110 is not particularly limited as long as it can transmit at least light in the visible wavelength region. In particular, the glass substrate 110 is preferably one that absorbs light in the near-infrared wavelength region. This is because by using the glass substrate 110 that absorbs light in the near-infrared wavelength region, an image quality close to human visibility characteristics can be obtained. Examples of the glass substrate 110 that absorbs light in the near-infrared wavelength region include absorption glass in which Cu ²⁺ (ion) is added to fluorophosphate glass or phosphate glass. In addition, borosilicate glass, quartz glass, soda-lime glass, alkali-free glass, and the like can be used.

(Optical thin film 120)
The optical thin film 120 is an antireflection film, and is provided on the surface 110A of the glass substrate 110 on the light incident side. The optical thin film 120 reduces the reflectance of the surface of the optical glass 100 and increases the transmittance. The optical thin film 120 includes, for example, a single layer film of MgF ₂ , a mixture film of Al ₂ O ₃ .TiO ₂ and ZrO ₂ , a multilayer film in which MgF ₂ is laminated, or an alternating multilayer film of SiO ₂ and TiO _2. ing. These single layer / multilayer films are formed on the surface 110A of the glass substrate 110 by a film forming method such as vacuum deposition or sputtering. The optical thin film 120 preferably has a physical film thickness of 0.2 μm to 8 μm.

(Optical thin film 130)
Further, an optical thin film 130 as a UVIR cut film for cutting ultraviolet (UV) rays and infrared (IR) rays is provided on the back surface 110B of the glass substrate 110. The optical thin film 130 is composed of a multilayer film in which dielectric films having different refractive indexes, such as SiO ₂ and TiO ₂ , are stacked. These multilayer films are formed on the back surface 110B of the glass substrate 110 by a film forming method such as vacuum deposition or sputtering. The optical thin film 130 preferably has a physical film thickness of 0.2 μm to 8 μm.

  In the above description, the optical thin film 120 is provided on the front surface 110A of the glass substrate 110 and the optical thin film 130 is provided on the back surface 110B of the glass substrate 110. However, the optical thin film 120 is provided on the back surface 110B of the glass substrate 110. The optical thin film 130 may be provided on the surface 110A of the 110. Further, the optical thin films 120 and 130 may be provided on the front surface 110 </ b> A of the glass substrate 110, and the optical thin films 120 and 130 may be provided on the back surface 110 </ b> B of the glass substrate 110. Further, when the transparent substrate 110 can sufficiently absorb light in the near-infrared wavelength region, only the optical thin film that cuts ultraviolet (UV) rays may be provided as the optical thin film 130.

(Side state of glass substrate 110)
The state of the side surface 110S of the glass substrate 110 will be described with reference to FIG.
At least one of the boundary L1 between the front surface 110A and the side surface 110S of the glass substrate 110 and the boundary L2 between the back surface 110B and the side surface 110S of the glass substrate 110 has unevenness, and the height difference of the unevenness is 0.5 μm to 60 μm. Furthermore, it is preferable that the surface roughness Ra of at least a part of the side surface 110S of the glass substrate 110 is 0.01 μm to 0.50 μm. In addition, the height difference of the unevenness | corrugation of the boundary L1, L2 of the glass substrate 110 and the surface roughness Ra of the side surface 110S can be measured using a known surface roughness measuring apparatus of a contact type or a non-contact type.

  When the height difference of the unevenness at the boundaries L1 and L2 is less than 0.5 μm, the adhesive area is small when the optical glass 100 is attached to the casing of the imaging device 300 described later with reference to FIG. There is a risk that strong adhesion cannot be achieved. Moreover, it is because defects, such as a crack and a chip | tip, will arise easily in the glass substrate 110, if the level difference of the unevenness | corrugation in boundary L1, L2 exceeds 60 micrometers.

  Furthermore, when the surface roughness Ra of at least a part of the side surface 110S of the glass substrate 110 is less than 0.01 μm, light obliquely incident on the solid-state image sensor is reflected on the surface of the solid-state image sensor and becomes stray light. The reflected image may adversely affect the captured image. Further, if the surface roughness Ra exceeds 0.50 μm, defects such as cracks and chipping are likely to occur in the glass substrate 110. In addition, surface roughness Ra means the arithmetic mean roughness based on JISB0601: 2001.

(Configuration of imaging device)
FIG. 2 is a cross-sectional view showing an example in which the optical glass 100 is used in the imaging device 300. The imaging apparatus 300 is obtained by sealing the optical glass 100 of the present invention with a thermosetting resin R or the like in a housing 320 containing a solid-state imaging device 310 (for example, CCD or CMOS). The housing 320 is provided with an opening 320a for accommodating the solid-state imaging device 310.

  The optical glass 100 is attached to the housing 320 in a state where stress is applied (worked) in a direction in which the optical glass 100 swells on the opposite side to the housing 320. An arrow α in FIG. 2 indicates the direction of stress acting on the optical glass 100 or the direction of deformation of the optical glass 100. That is, the optical glass 100 is subjected to a stress that has a convex shape on the side that is not bonded to the housing 320.

  The stress acting on the optical glass 100 is the internal stress of the optical thin film 120, 130 in the direction parallel to the main surface (front surface 110A, back surface 110B) of the glass substrate 110 described later, or the heat of the glass substrate 110 and the optical thin film 120, 130. This is caused by the difference in expansion coefficient. When the internal stress or the like acts on the optical glass 100, the optical glass 100 is deformed in a direction in which it swells on the opposite side to the housing 320. Therefore, the stress acting in the direction in which the optical glass 100 in the present invention swells on the opposite side to the housing 320 can be expressed by converting the amount of deformation into stress.

The stress acting on the optical glass 100 can be calculated by converting the curvature radius of the warp from the warp amount of the optical glass 100 and calculating the following Stoney formula (formula (1)) (the optical glass 100 is a circular substrate). in the case of).
^{σ = Et 2/6 (1} -ν) Rt '··· (1)
However,
σ: Stress E: Young's modulus of optical glass 100 t: Plate thickness of optical glass 100 ν: Poisson's ratio of optical glass 100 R: Curvature radius of curvature of optical glass 100 t ′: Thickness of optical thin film

When the optical glass 100 is a strip substrate, the stress acting on the optical glass 100 is calculated using the following equation (2).
^{σ = Et 2/3 (1} -ν) Rt '··· (2)

  Specifically, the warp amount of the optical glass 100 is measured by a known means such as a laser displacement meter. Next, the radius of curvature is calculated from the measured amount of warpage and the dimensions of the optical glass 100. Then, the stress of the optical glass 100 is calculated by substituting the calculated value into the equation (1) or (2). In addition to the above method, the stress acting on the optical glass 100 can be measured by a known method.

  Further, the stress acting on the optical glass 100 is preferably 5 MPa to 150 MPa. If the stress acting on the optical glass 100 is less than 5 MPa, the effect of suppressing the damage of the optical glass 100 described later cannot be sufficiently obtained. In addition, when the stress acting on the optical glass 100 exceeds 150 MPa, the amount of warpage increases, and there is a possibility that an image captured by the solid-state image sensor 310 may be defective. The stress acting on the optical glass 100 is preferably 10 MPa to 125 MPa, more preferably 10 MPa to 100 MPa.

  A strong impact may be applied to a portable electronic device (for example, a mobile terminal such as a mobile phone or a smartphone) on which the imaging device 300 is mounted due to dropping or the like. At that time, a strong impact is similarly applied to the optical glass 100 used in the imaging apparatus 300. When the optical glass 100 bends in the thickness direction of the optical glass 100 due to an impact, the optical glass 100 is displaced in a direction away from the housing 320 and a state in which the optical glass 100 is in contact with the housing 320 and in a direction approaching the solid-state imaging device 310 side. Are alternately repeated, and the impact is absorbed by gradually decreasing the amplitude.

  When the optical glass 100 is displaced in a direction away from the housing 320, the stress acting on the optical glass 100 is substantially an adhesive (thermosetting resin or ultraviolet curable resin) joining the optical glass 100 and the housing 320. Etc.) and is reduced by the elastic force. Further, since there is no contact between the optical glass 100 and other members, high stress does not act on the optical glass 100 locally.

  On the other hand, when the optical glass 100 is in close contact with the housing 320 and is displaced in a direction approaching the solid-state imaging device 310 side, the optical glass 100 and the end portion of the opening 320a of the housing 320 are in close contact with each other. High stress acts on Thereby, the stress which acted on the optical glass 100 propagates in the plane direction, and it is conceivable that the optical glass 100 is damaged due to the cracks starting from the chipping of the boundary L1 or the boundary L2, the minute cracks, or the like.

  The optical glass 100 of the present invention is attached to the housing 320 in a state where stress is applied (worked) in a direction in which the optical glass 100 swells on the opposite side of the housing 320, so that the optical glass 100 is in the thickness direction. Even if an impact such as displacement is applied, it is possible to prevent the optical glass 100 from coming into close contact with the housing 320 and moving toward the solid-state imaging device 310, so that the optical glass due to an impact such as a drop of the imaging device 300 can be suppressed. 100 damage can be suppressed.

(Applying stress to optical glass)
There are four means described below for making the optical glass 100 in a state in which stress is applied in a direction in which the optical glass 100 swells in the direction opposite to the casing 320. Hereinafter, the first to fourth means will be described with reference to FIG. In addition, the same code | symbol is attached | subjected to the structure same as the structure demonstrated in FIG. 1, FIG. 2, and the overlapping description is abbreviate | omitted. Further, the surface 110A of the glass substrate 110 is defined as a first main surface on the side bonded to the housing 320, and a surface facing the first main surface is defined as a second main surface.

(First means: see FIG. 3A)
As a first means, an optical thin film 130 is formed on the back surface 110B (second main surface) of the glass substrate 110, and the internal stress of the optical thin film 130 is a compressive stress parallel to the second main surface of the glass substrate 110. To be. By doing so, stress acts on the optical glass 100 in the direction of the arrow α in FIG. When the optical glass 100 has a convex shape on the side opposite to the housing 320, it can be said that stress is acting on the optical glass 100 in such a direction, but the optical glass 100 is not necessarily convex. It is not necessary that the stress is applied, and it is important that the stress acts in the direction of the arrow α.

(Second means: see FIG. 3B)
As a second means, an optical thin film 120 is formed on the surface 110A (first main surface) of the glass substrate 110, and the internal stress of the optical thin film 120 is a tensile stress parallel to the first main surface of the glass substrate 110. To be. By doing so, stress acts on the optical glass 100 in the direction of the arrow α.

(Third means: see FIG. 3C)
As a third means, optical thin films 130 and 120 are formed on both the back surface 110B (second main surface) and the front surface 110A (first main surface) of the glass substrate 110, and are formed on the second main surface. The internal stress parallel to the second main surface of the glass substrate 110 of the optical thin film 130 is A and the internal stress parallel to the first main surface of the glass substrate 110 of the optical thin film 120 formed on the first main surface. Is B, the compressive stress is a positive value, and the tensile stress is a negative value, the value of AB is made to exceed zero. By doing so, stress acts on the optical glass 100 in the direction of the arrow α. That is, when the internal stresses of the optical thin films 130 and 120 formed on the first main surface and the second main surface are offset, it means that compressive stress remains on the second main surface side.

  Therefore, if a stress acts on the optical glass 100 in the direction of the arrow α, the first and second glass substrates 110 of the optical thin films 120 and 130 formed on the first main surface and the second main surface are used. Both internal stresses parallel to the main surface may be compressive stresses or tensile stresses. When the internal stress of the optical thin film 130 formed on the second main surface is a compressive stress and the internal stress of the optical thin film 120 formed on the first main surface is a tensile stress, the above-described relationship is always satisfied. If the value of B) is too large, the amount of warping of the optical glass 100 may increase and affect the optical characteristics. Therefore, the stress should not be excessively increased in the direction of the arrow α acting on the optical glass 100. It is.

(Fourth means: see FIG. 3A)
As a fourth means, the optical thin film 130 is formed on the back surface 110B (second main surface) of the glass substrate 110, and the thermal expansion coefficient is 100 × 10 ⁻⁷ / K to 150 × 10 ⁻⁷ / K. Is to use. When an optical thin film is formed on the glass substrate 110, a vacuum deposition method, an ion assist deposition method, a sputtering method, or the like is used. In any of these methods, the glass substrate 110 is held at a high temperature (a temperature higher than room temperature) when forming the optical thin film.

Therefore, when the thermal expansion coefficient of the glass substrate 110 is the above-mentioned value, thermal shrinkage occurs more than the optical thin film 130 when the glass substrate reaches room temperature after the optical thin film 130 is formed, and the optical glass 100 is oriented in the direction of the arrow α. Stress will act. When the thermal expansion coefficient of the glass substrate 110 is less than 100 × 10 ⁻⁷ / K, the difference in thermal expansion coefficient from the optical thin film 130 is small, and the stress acting on the optical glass 100 is not sufficient. Moreover, there exists a possibility that the stress which acts on the optical glass 100 may become large too much that the thermal expansion coefficient of the glass substrate 110 exceeds 150 * 10 < ^-7 > / K.

Examples of the glass having the above-described thermal expansion coefficient include fluorophosphate glass.
In the case of fluorophosphate glass, the glass substrate 110 is preferably the following components.
In cation% display,
P ⁵⁺ 20-45%,
Al ³⁺ 1-25%,
R ⁺ 1-30% (where R ⁺ is the total amount of Li ⁺ , Na ⁺ , K ⁺ )
Cu ²⁺ 1-15%,
R ²⁺ 1-50% (where R ²⁺ is the total amount of Mg ²⁺ , Ca ²⁺ , Sr ²⁺ , Ba ²⁺ , Zn ²⁺ ),
Anion% display
F ^- 10-65%,
O ^2-35 to 90% containing.

  Further, as a method for forming the optical thin films 120 and 130 on the glass substrate 110, a vacuum deposition method, an ion assist deposition method (ion beam assist method), an ion plating method, a sputtering method, an ion beam sputtering method, or the like is used. it can.

  The method for cutting the optical glass 100 of the present invention includes a method for forming a modified region in the glass substrate 110 by irradiation with a laser beam, a method for forming a cut line with a diamond cutter, a method for breaking by a dicing method, a method for cutting by dicing, An appropriate cutting method such as a method of cutting by forming a crack on the glass surface with a laser beam, rapidly cooling it and causing the crack to propagate in the thickness direction can be used.

  The optical glass 100 of the present invention is not easily damaged when bonded to the housing 320. Therefore, it is not necessary to chamfer or round the end face of the optical glass 100 (at least one of the boundary between the front surface 110A and the side surface 110S of the glass substrate 110 and the boundary between the back surface 110B and the side surface 110S of the glass substrate 110). Necessary steps can be omitted. As a result, the manufacturing cost of the optical glass 100 can be suppressed, and the optical glass 100 can be manufactured with high productivity. The optical glass 100 of the present invention is not limited to a housing that houses semiconductor elements, and can be suitably used for the optical glass 100 that is used for the purpose of covering the openings of various housings. In addition, the end surface of the optical glass 100 may be chamfered or rounded, and by doing so, the strength of the optical glass 100 can be further increased.

  EXAMPLES Hereinafter, although it demonstrates in detail based on the Example of this invention, this invention is not limited only to these Examples. As glass substrates of Examples and Comparative Examples, fluorophosphate glass (manufactured by AGC Techno Glass, NF-50, plate thickness 0.3 mm, dimensions 100 mm × 100 mm) was prepared. In addition, the glass substrate (corresponding to the glass substrate 110) of the example is glass within the composition range described in paragraph 0039.

As the optical glass of the example (corresponding to the optical glass 100), an antireflection film (corresponding to the optical thin film 120) was formed on one main surface of the glass substrate. The antireflection film has a three-layer structure in which the first layer is Al ₂ O ₃ from the fluorophosphate glass (glass substrate) side, the second layer is a mixture film of TiO ₂ and ZrO _2, and the third layer is MgF _2. . The antireflection film was formed by a vacuum deposition method. The physical thickness of the antireflection film (the total of the first to third layers) was 0.3 μm.

Then, an ultraviolet and infrared reflective film (corresponding to the optical thin film 130) was formed on the other main surface of the glass substrate. The UV and infrared reflective films are composed of TiO ₂ as the first layer, SiO _{2 as} the second layer, and the third and subsequent layers of TiO ₂ and SiO ₂ from the fluorophosphate glass (glass substrate) side (60 layers in total). Consists of. The ultraviolet and infrared reflective films were formed by a vacuum deposition method. The physical film thickness (total of all 60 layers) of the ultraviolet and infrared reflective films was 7.0 μm. In addition, as a comparative example, a material in which no optical thin film was provided on any main surface of the fluorophosphate glass (glass substrate) was prepared.

  When the optical glass of an Example and a comparative example was observed from the side surface direction, as for the optical glass of an Example, the main surface side in which the ultraviolet-ray and infrared rays reflecting film were formed became convex shape. On the other hand, the optical glass of the comparative example was flat. In addition, the stress acting (working) on the optical glass was calculated.

  As a method for calculating the stress, first, the warpage amount of the optical glass was measured with a laser displacement meter, and the curvature radius of the warpage was calculated from the warpage amount and the outer diameter dimension. Next, the calculated value was substituted into Stoney's equation (Equation (2)) to calculate the stress of the optical glass. As a result of the calculation, the stress acting on the optical glass of the example was 64 MPa to 90 MPa, whereas the stress acting on the optical glass of the comparative example was 0 MPa.

  In addition, the optical glass of an Example and a comparative example cut | disconnected by the method of forming a cut line in the surface of an optical glass with a diamond cutter, and cracking by hand from the cut line later.

  Next, the strengths of the optical glasses of Examples and Comparative Examples were examined by the following drop test. Specifically, each optical glass was bonded with a thermosetting resin to an opening of a concave resin package having an opening of 7 mm × 7 mm imitating the housing of the imaging device. In the optical glass of the example, the main surface on which the antireflection film was formed was used as the adhesive surface. Then, the resin package with the optical glass attached is fixed inside a metal box having an external shape of 100 mm × 80 mm × 20 mm imitating a digital camera, and dropped onto the asphalt ground from a height of 1 m to optical glass. The presence or absence of damage was confirmed. The optical glass was dropped in a posture in which the main surface of the optical glass and the ground were parallel.

  As a result of the drop test, two of the ten optical glasses in the example were damaged. On the other hand, 8 of the 10 optical glasses of the comparative example were damaged. From the results of these drop tests, it can be said that the optical glass of the example of the present invention has a high strength that is difficult to break even when an external force such as an impact is applied as compared with the optical glass of the comparative example.

  The glass substrate of the present invention has a thin plate thickness of 0.15 mm to 1.00 mm and is applied with bending stress, for example, a cover glass used for a solid-state imaging device (CCD or CMOS) such as a digital still camera, It can be suitably used for optical glass such as a near infrared cut filter.

  DESCRIPTION OF SYMBOLS 100 ... Optical glass, 110 ... Glass substrate, 120, 130 ... Optical thin film, 300 ... Imaging device, 310 ... Solid-state image sensor, 320 ... Housing | casing.

Claims (9)

An optical glass bonded to the housing so as to cover the opening of the housing,
A glass substrate having a first main surface to be joined to the housing and a second main surface facing the first main surface;
An optical thin film provided at least on the first main surface ,
The internal stress of the optical thin film provided on the first main surface is a tensile stress,
The optical glass is subjected to a stress of 5 MPa to 150 MPa in a direction in which it swells on the side opposite to the casing.   The optical thin film is formed on both the first main surface and the second main surface, the internal stress of the optical thin film formed on the second main surface is A, and the first main surface 2. The value of A-B exceeds 0 when the internal stress B of the optical thin film formed on the substrate is set to a positive value and the tensile stress is a negative value. Optical glass. Wherein the optical thin film, optical glass according to claim 1 or 2 physical thickness, characterized in that a 8μm from 0.2 [mu] m. The glass substrate has a side surface between the first main surface and the second main surface,
At least one of the boundary between the boundary and the side surface and the second major surface of said side surface and said first main surface, chamfering or claims 1 to 3, characterized in that there are no round-up The optical glass of any one. The glass substrate has a side surface between the first main surface and the second main surface,
At least one of the boundary between the first main surface and the side surface and the boundary between the second main surface and the side surface has unevenness, and the height difference of the unevenness is 0.5 μm to 60 μm. The optical glass according to any one of claims 1 to 4 , characterized in that: The glass substrate has a side surface between the first main surface and the second main surface,
The optical glass according to any one of claims 1 to 5 , wherein the surface roughness Ra of at least a part of the side surface is 0.01 µm to 0.50 µm. The optical glass according to any one of claims 1 to 6 , wherein the optical thin film is at least one of an antireflection film, an infrared shielding film, and an ultraviolet shielding film. Wherein the housing, the optical glass according to any one of claims 1 to 7, characterized in that for accommodating the semiconductor element The optical glass according to claim 8 , wherein the semiconductor element is a solid-state imaging element.

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