JP2002082208A - Antireflection film and optical component with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To dispense with a step for eliminating or preventing yellowing and flawing before film formation and obtain an antireflection film having high adhesion to the surface of a lens and good reflectance characteristics over the wide wavelength range of visible light. SOLUTION: In the antireflection film obtained by laminating plural materials on the surface of an optical component comprising optical glass, the first layer counted from the surface side of the optical component comprises material containing >=50 mol% silicon oxide, and when the refractive index of the m-th layer (m=1-5) to light of 520 nm wavelength is represented by nm and the optical film thickness by nmdm, 14<=n1d1<=115, 1.44<=n1<=1.48, 15<=n2d2<=71, 1.90<=n2<=2.20, 27<=n3d3<=74, 1.35<=n3<=1.40, 246<=n4d4<=318, 1.90<=n4<=2.20, 108<=n5d5<=147 and 1.35<=n5<=1.40 are satisfied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antireflection film used for an optical component such as an eyeglass lens, an optical lens for an optical device such as a camera or a microscope, and an optical component having the same.

[0002]

2. Description of the Related Art Conventionally, spectacle lenses have a reflection function for preventing reflection, and an optical lens used for an optical device such as a camera has a reflection function for preventing reflection and ghost and flare. It is common practice to provide a barrier film. JP-A-57-112701 discloses a visible light having a five-layer structure in which low refractive index material layers and high refractive index material layers are alternately laminated from the lens surface side, and the outermost layer is a low refractive index material layer. An anti-reflection coating (prior art) is disclosed. According to this, the optical film thickness is the first from the surface side, where λ is approximately 510 nm of the center wavelength in the visible light region.
The total of the layers from the layer to the third layer is λ / 2, the fourth layer is λ / 2,
The layers are configured to be λ / 4, and the first
The film thickness of each layer from the layer to the third layer is determined by the equivalent approximate film method so that the total optical film thickness is λ / 2 and the refractive index is 1.65. Thus, an antireflection film having a low reflectance in the visible light region has been obtained.

On the other hand, optical components such as spectacle lenses and optical lenses are generally polished from blocks or the like to form an optically functional surface (hereinafter, referred to as a lens surface) in many cases. A phenomenon called burns or scratches occurs in the cleaning step and the staying step in the middle of the steps from these steps to the film forming step. The burn phenomenon includes blue burn and white burn. Blue discoloration occurs when the lens surface is left undisturbed in the air without being protected in the stagnation process, and the components in the lens glass material undergo a chemical reaction due to the contact with water used in the polishing process. Is a phenomenon caused by being covered with a thin film having a low refractive index, and is referred to as having a blue interference color. In addition, white scorch causes soluble components in the lens glass and water to react with each other, eroding the glass surface, and causing elution components and reaction products between the elution components and gases such as CO ₂ to precipitate on the lens surface. This is a phenomenon that occurs when the surface looks cloudy and white. The level at which burns occur depends on the components of the lens glass material, but is generally remarkable in La-based, SK-based, and SF-based glass materials.

[0004] On the other hand, scratches are caused by the hardness of the glass material. Although this is a level that does not cause any problem, in the cleaning process performed after the polishing process or before the film forming process of the antireflection film, etc., the glass surface is eroded by components contained in the cleaning solution, and the fine particles generated in the polishing process are generated. The growth of the scratches becomes noticeable to the extent that they can be seen with the naked eye.

[0005]

In the anti-reflection film disclosed in Japanese Patent Application Laid-Open No. 57-112701, which is a prior art, such burns and scratches have already occurred on the lens surface before the film formation step of the anti-reflection film. When this occurred, burns and scratches were observed even when the antireflection film having the above-mentioned laminated structure was provided, and in many cases, the appearance was inferior. Further, the antireflection film also has a problem that sufficient adhesion to the lens surface cannot be obtained. For this reason, the time of the staying step before providing the antireflection film, which is a cause of burns and scratches, is reduced as much as possible, and the covering step of covering the lens surface with a protective paint that is less likely to burn, or immediately before the formation of the antireflection film This problem was addressed by adding a polishing process to remove burns and scratches. However, reducing the time of the stagnation process leads to a decrease in the number of lenses to be input for each film formation lot, and the addition of the coating process and the polishing process involves an increase in the number of processes. Had become.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned conventional problems, and an object of the invention according to claims 1, 2 or 3 is to form an antireflection film on an optical component before forming the film. By providing an antireflection film having good reflectance characteristics over a wide wavelength range of visible light and an optical component having the same, which eliminates the need for a step of removing or preventing burns and scratches, and has high adhesion to the lens surface. is there.

[0007]

According to a first aspect of the present invention, there is provided an antireflection film formed by laminating a plurality of materials on a surface of an optical component made of optical glass. The first layer, counting from the surface side of the component, is made of a material containing silicon oxide in a molar ratio of 50% or more,
When the refractive index _{n m} for light having a wavelength 520nm of the m-th layer (m = 1 to 5), the optical film thickness was _{n m d m, 14 ≦ n} 1 d 1 ≦ 115, 1.44 ≦ n 1 ≦ 1.
48, 15 ≦ n ₂ d ₂ ≦ 71, 1.90 ≦ n ₂ ≦ 2.
20, 27 ≦ n ₃ d ₃ ≦ 74, 1.35 ≦ n ₃ ≦ 1.
40, 246 ≦ n ₄ d ₄ ≦ 318, 1.90 ≦ n ₄ ≦ 2.
20, 108 ≦ n ₅ d ₅ ≦ 147, 1.35 ≦ n ₅ ≦ 1.
40,

According to a second aspect of the present invention, in the antireflection film formed by laminating a plurality of materials on the surface of an optical component made of optical glass, the first layer counted from the surface side of the optical component is made of silicon oxide. Consisting of a material containing at least 50% by mole of
And the optical thickness is 14 to 115 nm, the second layer is made of a mixture containing at least zirconium oxide and tantalum oxide, and the optical thickness is 15 to 71 n.
m, the third layer is made of a material containing at least magnesium fluoride, and has an optical thickness of 27 to 7
4 nm, the fourth layer is made of a mixture containing at least zirconium oxide and tantalum oxide, and has an optical thickness of 246 to 318 nm, and the fifth layer is made of a material containing at least magnesium fluoride. And the optical film thickness is 108 to 147 nm.

According to a third aspect of the present invention, in an optical component, the antireflection film according to the first or second aspect is provided on a surface thereof.

In the antireflection film according to the first aspect of the present invention,
Anti-reflective coating on optical glass surface
The first layer, counted from the surface side of the optical component, is made of silicon oxide (S
iO _xAnd x is a material containing 1 ≦ x ≦ 2) in a molar ratio of 50% or more.
Optical components before the anti-reflection coating is formed
Makes burns on the surface less noticeable. This is the optical section
If burns occur on the surface of the product, the reflection characteristics of the surface
A silicon oxide coating, a low refractive index material, was provided on the surface of the
This is supported by the fact that it has characteristics similar to those of the case.
In addition, the key generated on the optical component surface before the formation of the anti-reflection coating
Is compensated by silicon oxide as a film-forming material,
Silicon oxide, which is the main component of optical glass,
It becomes less noticeable by embodying. In addition, silicon oxide
Components made of optical glass containing as main component and silicon oxide
Anti-reflective coating made of a material containing 50% or more of
Optical components and anti-reflection due to coupling effect with layer
The adhesion to the film is improved.

Further, by limiting the refractive index and the optical film thickness of each of the first to fifth layers with respect to light having a wavelength of 520 nm to the above ranges, the reflectance of the antireflection film can be increased over a wide wavelength range of visible light. Good reflectance characteristics can be obtained over the entire region. Here, the good reflectance characteristic means that the reflectance R of the antireflection film is, for example, 440 nm ≦ λ ≦ 650 nm and R ≦ 1% with respect to the wavelength λ of the light incident parallel to the optical axis of the optical component. Λ = 420 nm, R ≦ 2%, and λ = 700 nm, meaning that R ≦ 2%.

More preferably, the m-th layer (m = 1 to 5)
The refractive index _{n m} for light having a wavelength 520 nm, the optical thickness _{n m d m, 29 ≦ n} 1 d 1 ≦ 97, 1.44 ≦ n 1 ≦ 1.
48, 20 ≦ n ₂ d ₂ ≦ 71, 1.90 ≦ n ₂ ≦ 2.
20, 36 ≦ n ₃ d ₃ ≦ 68, 1.35 ≦ n ₃ ≦ 1.
40, 257 ≦ n ₄ d ₄ ≦ 318, 1.90 ≦ n ₄ ≦ 2.
20, 116 ≦ n ₅ d ₅ ≦ 142, 1.35 ≦ n ₅ ≦ 1.
40, the reflectance R of the antireflection film is 440 nm ≦ λ ≦ 650 nm, R ≦ 0.6%, λ = 420 nm, R ≦ 2%, λ = 700 nm, R ≦ 2%. Even when a plurality of components are combined, good reflectance characteristics can be obtained as a whole.

In the antireflection film according to the first aspect of the present invention, the glass material of the optical glass to be formed is not particularly limited, and the d-line (wavelength: 587 nm) is used.
Any glass material having a refractive index of 1.465 to 1.925 can be used, and infrared absorbing glass can also be used. As the method for forming the antireflection film, an ion assist method, a sputtering method, or the like can be used in addition to the vacuum evaporation method.

In the antireflection film according to the invention, the first layer of the antireflection film laminated on the surface of the optical component made of optical glass, counted from the surface side of the optical component, is formed of silicon oxide (SiO 2). _{2. The method according to} claim 1, wherein _x and x are made of a material containing 50% or more of 1 ≦ x ≦ 2) in a molar ratio and the optical film thickness is 14 to 115 nm.
It acts like a layer.

Further, the second layer and the fourth layer are made of a high-refractive-index material layer composed of a mixture containing at least zirconium oxide and tantalum oxide, and the optical thickness of each layer is within the above-mentioned range. An antireflection film having a stable film quality can be obtained as compared with a heterogeneous film quality obtained from only zirconium oxide that has been used. Here, the high refractive index material layer is formed of a mixture of zirconium oxide (ZrO2) and tantalum oxide (Ta2O5) only (hereinafter, ZrO2).
2: Ta2O5 mixture), the weight ratio of both is in the range of 95: 5 to 5:95, preferably 95: 5 to 50:50, and more preferably 95: 5. When the ratio is in the range of 78:22, the film formation rate, the state of the material being formed, and the film quality after the film formation can be stably obtained, for example, when performing vacuum deposition using an electron gun. _Further, ZrO 2: _Ta 2 _{O 5} for other materials added to the mixture, the refractive index _{n H} with respect to light having a wavelength lambda = 520 nm obtained when the film formation by mixing these 1.
There is no particular limitation as long as it is within the range of 90 ≦ n _H ≦ 2.20, and TiO ₂ , Nb ₂ O ₅ , Y ₂ O ₃ or the like may be used. The mixing ratio between the ZrO ₂ : Ta ₂ O ₅ mixture and these materials is relatively large in the ZrO ₂ : Ta ₂ O ₅ mixture, such as 100: 0 to 75:25 by weight. It is easy to form a film, but 50:50 is acceptable.

Further, at least the third layer and the fifth layer are
Low-refractive-index material made of a material containing magnesium fluoride
And the optical thickness of each layer within the above-mentioned range.
With this, the reflectivity of the anti-reflection coating is spread over a wide wavelength range of visible light.
As a result, good reflectance characteristics can be obtained. Magnesium fluoride
Nesium (MgF₂About other materials added to
Is a wavelength λ = 52 obtained when these are mixed to form a film.
Refractive index n for 0 nm light_LIs 1.35 ≦ n_L≤
If it is included in the range of 1.40, it is particularly limited.
Without SiO₂, Na₃AlF₆, LiF, CaF₂ etc
It doesn't matter. MgF ₂And the mixing ratio with other materials, weight
The ratio is in the range of 100: 0 to 50:50.
It is preferable from the viewpoint of securing a folding ratio and a stable composition of a film forming material,
More preferably within the range of 100: 0 to 70:30
Is desirable. Further, the anti-reflection coating of the invention according to claim 2
In the case of the stop film, the glass material of the optical glass to be formed is also used.
The method for forming the anti-reflection film and the anti-reflection film is the same as in claim 1.
Materials and methods can be used.

In the optical component according to the third aspect of the invention, the antireflection film according to the first or second aspect is formed on the surface of the optical component, so that burns and scratches are not conspicuous and the adhesion of the antireflection film is excellent. And exhibits good reflectance characteristics over a wide wavelength range of visible light.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Prior to the description of a specific embodiment of the present invention, a vacuum deposition apparatus used for forming an antireflection film according to the embodiment will be described. In FIG. 1, a vacuum deposition apparatus 1 mainly includes a film forming chamber 2 for forming a film and an exhaust device 3 for evacuating the inside of the film forming chamber 2. The film forming chamber 2 includes a housing as a main body,
And a door rotatably supported so as to be open to the housing, but FIG. 1 shows a state where the door is removed.

An electron gun 4 and an electron gun 5 for irradiating the material with an electron beam are provided below the film forming chamber 2.
Are disposed substantially symmetrically with respect to the center of the film forming chamber 2. A material crucible 6 and a material crucible 7 are also disposed substantially horizontally symmetrically with respect to the center of the film forming chamber 2 in the vicinity of the electron gun 4 and the electron gun 5, respectively.
The material crucible 6 has an accommodating portion 6a for accommodating the material to be formed on the upper surface, and the material crucible 7 has accommodating portions 7a and 7b for accommodating the material to be formed on the upper surface. The accommodation portion 7a and the accommodation portion 7b are provided at symmetrical positions with respect to the central axis of the material crucible 7. A rotating shaft 8 is provided directly below the material crucible 7 through an opening formed in the bottom surface of the film forming chamber 2. The upper end of the rotating shaft 8 is fixed to the bottom surface of the material crucible 7, and the lower end is It is connected to a motor 9 provided outside the film forming chamber 2. An O-ring 10 is provided in a gap between the opening and the rotating shaft 8 to rotatably support the rotating shaft 8 and secure airtightness in the film forming chamber 2. The housing part 7a and the housing part 7b
By rotating the material crucible 7 by the rotation of the motor 9,
It approaches and separates from the electron gun 5, respectively.

In the upper part of the film forming chamber 2, a spherical dome 11 is provided with its concave surface facing downward. The dome 11 is rotatable around a center of the film forming chamber 2 by a driving unit (not shown). At the top of the dome 11,
An opening is formed, and a cylindrical support member 1 is formed in the opening.
2 is fitted and fixed to the upper surface of the film forming chamber 2. At the lower end of the inner peripheral surface of the support member 12, a monitoring glass 13 for monitoring the film thickness is supported with the deposition surface facing downward. A reflection type film thickness monitor 14 is provided above the outside of the film forming chamber 2 so as to face the monitoring glass 13. The reflection type film thickness monitor 14 is used for the monitoring glass 1.
By irradiating light to 3 and measuring the amount of reflected light (reflectance), the thickness of the film formed on the monitoring glass 13 is monitored. A holder hole 15 is formed at an intermediate position between the top and the end of the dome 11, so that a substrate holder 17 on which a glass substrate 16 on which a film is to be formed is placed can be set.

Shutters 18 and 19 are disposed above the material crucible 6 and the material crucible 7 and below the dome 11, respectively. Shutter 18, 1
9 are rotated in a horizontal plane, so that
a and the material housed in the housing portions 7a and 7b
1 is reached or blocked. On the other hand, the exhaust device 3 includes a rotary pump 20, a diffusion pump 21, a valve 22, and a pipe 23 connecting these components to each other. One end of the pipe 23 communicates with the inside of the film forming chamber 2.

Next, a vacuum deposition method using the vacuum deposition apparatus 1 having the above configuration will be described. First, deposition chamber 2
The door of the first layer is opened and the material of the first layer is stored
a, the material of the third layer, the material of the fifth layer, the second layer,
The material of the fourth layer is housed in the housing portion 6a of the material crucible 6, respectively. Next, a glass substrate 16 as an optical component on which a film is to be formed is set on a substrate holder 17 with the film forming surface thereof facing downward, and the substrate holder 17 on which the glass substrate 16 is set is inserted into the holder hole 15. Fit and place. After the door of the film forming chamber 2 is closed, the inside of the film forming chamber 2 is evacuated by an exhaust device 3 including a rotary pump 20, a diffusion pump 21, a valve 22, and a pipe 23, and the dome 11 is driven at 15 rpm by a driving unit (not shown). Rotate with. The degree of vacuum inside the film forming chamber 2 is 2.6 × 10
^{When the} pressure reaches ^-3 Pa, the current value of the electron gun 5 is increased to sufficiently heat the material accommodated in the accommodating portion 7a of the material crucible 7, then the shutter 19 is opened, and the film forming surface of the glass substrate 16 is The material of the first layer is formed. Reflection type film thickness monitor 14
When the film thickness of the monitoring glass 13 monitored in step (1) reaches a predetermined value, the shutter 19 is closed to block the material toward the glass substrate 16, and the current value of the electron gun 5 is reduced.

Next, after increasing the current value of the electron gun 4 to sufficiently heat the material of the second layer stored in the storage portion 6a of the material crucible 6, the shutter 18 is opened and the glass substrate 16 is opened.
The material of the second layer is formed on the film forming surface. When the film thickness of the monitoring glass 13 monitored by the reflection type film thickness monitor 14 reaches a predetermined value, the shutter 18 is closed and the glass substrate 1 is closed.
The material crucible 7 is turned halfway through the rotation shaft 8 by driving the motor 9 to block the material toward the electron gun 6 and reduce the current value of the electron gun 4, and the housing portion 7 b is positioned close to the electron gun 5 (initially, (The position where the accommodation portion 7a was). Electron gun 5
After sufficiently heating the material stored in the storage portion 7b of the material crucible 7 by opening the current value of
The material of the third layer is formed on the film forming surface of the glass substrate 16. When the film thickness of the monitoring glass 13 monitored by the reflection type film thickness monitor 14 reaches a predetermined value, the shutter 19 is closed to block the material toward the glass substrate 16 and reduce the current value of the electron gun 5. Similarly, the material of the fourth layer and the material of the fifth layer are sequentially formed on the glass substrate 16 in the same manner, and an antireflection film composed of five layers is formed on the glass substrate 16.

Next, specific embodiments of the present invention will be described with reference to embodiments including Examples 1 to 3 and a comparative example.

(Embodiment) Glass base as optical component
In the plate, as Example 1, (a) S-BAL11 (n) _d:
1.57), (b) SK16 (n_d:
1.62), (c) S-LAL14 (n
_d: 1.70) three types of optical glass as optical glass
The gap is also made by Ohara Co., Ltd.)
After that, it was exposed to 40 ° C and 90% RH for 1 week.
On the other hand, an anti-reflection film was formed by the vacuum evaporation method described above.
Was.

As a film forming material, counting from the surface side of the glass substrate, SiO ₂ (n: 1.46) is used for the first layer, and ZrO ₂ and Ta ₂ O ₅ are used for the _second and fourth layers. A mixture (n: 2.07) mixed at a weight ratio of 1: 1, MgF ₂ (n: 1.39) for the third and fifth layers was used to form a five-layer antireflection film. Here, n is the refractive index of each material with respect to light of wavelength λ = 520 nm. Example 1 for each glass material used,
Table 1 shows the optical film thickness of each layer for Examples 2 and 3.
FIGS. 2 to 4 show the spectral reflectance characteristics of a few wavelengths, and Table 2 shows the reflectance for typical wavelengths. In Table 2, the antireflection films formed on the glass substrates (a), (b), and (c) of Examples 1, 2, and 3 were replaced with the antireflection films (a), (b), and (b), respectively. (C).

[0027]

[Table 1]

[0028]

[Table 2]

The antireflection films (a) of Examples 1, 2, and 3
The reflectances of (b) and (c) are all as shown in Table 2,
2% or less at λ = 420 nm with respect to the wavelength λ of the incident light,
1% or less at 40 nm ≦ λ ≦ 650 nm, λ = 700 nm
And excellent reflectance characteristics over a wide wavelength range of visible light of 2% or less.

Next, for the antireflection films (a), (b), and (c) of Examples 1, 2, and 3, cellophane for evaluating the appearance before and after film formation and testing the adhesion of the film after film formation. Table 3 shows the results of the tape peeling test and the abrasion test for testing abrasion resistance. Appearance evaluation is a three-level evaluation,
A state where neither burns nor scratches are observed is “1”, and a state after one week exposure in a 40 ° C. 90% RH environment after the polishing step and the cleaning step is “3”. The state slightly observed was designated as “2”. “1” and “2” are practical levels, but “3”
Is not available.

In the cellophane tape peeling test, an adhesive surface of a 24-mm cellophane tape (manufactured by Nichiban Co., Ltd.) was attached to the film-forming surface, and was lifted in a 90 ° direction with respect to the film-forming surface.
This was performed by confirming the state of peeling of the film. "No peeling" means that no deposits are found on the cellophane tape side, and "No peeling" means that any deposits are found on the cellophane tape side.
In the abrasion test, a solvent-soaked silbon paper was applied to the film-forming surface, and a load of 200 was applied.
After reciprocating 500 times with gf, the state of scratches on the film formation surface was confirmed.

[0032]

[Table 3]

According to Examples 1, 2, and 3, scorching and scratching of the glass substrate become inconspicuous and the practical level is achieved, and good results are obtained in the cellophane tape peeling test and the abrasion test for the antireflection film. I was able to.

[0034] In addition, the refractive index _{n d} is 1.465 to 1.9
As a result of a detailed study on an antireflection film using a glass material in the range of 25 as a glass substrate, the following facts were found. That is, the refractive index _{n d} 1.465 to 1.
If the optical film thickness of each layer of the antireflection film is as shown in Table 4 with respect to the glass substrate in the range of 65, 1.65 to 1.75, 1.75 to 1.925, the wavelength of the incident light For λ,
2% or less at λ = 420 nm, 440 nm ≦ λ ≦ 650 n
It was found that excellent reflectance characteristics were exhibited over a wide wavelength range of visible light, such as 1% or less at m and 2% or less at λ = 700 nm.

[0035]

[Table 4]

Further, if the optical film thickness of each layer of the antireflection film is as shown in Table 5, λ = 42 with respect to the wavelength λ of the incident light.
2% or less at 0 nm and 0.0 at 440 nm ≦ λ ≦ 650 nm.
6% or less, 2% or less at λ = 700 nm, showing excellent reflectivity characteristics over a wide wavelength range of visible light. Even when a plurality of optical components are combined, good reflectivity characteristics can be obtained as a whole. all right.

[0037]

[Table 5]

[0038] As described above in detail, the antireflection film of this embodiment, the refractive index _{n d} can be used glass material in the range of 1.465 to 1.925 as a glass substrate. Also, there is no problem even if infrared absorbing glass is used for the glass substrate. On the other hand, the method for forming the antireflection film according to the present embodiment is not limited to the vacuum evaporation method, and the same effect can be obtained by an ion assist method or a sputtering method.

The material for forming the antireflection film is not limited to the material described in the present embodiment, and the first layer counted from the surface side of the optical component may be formed of silicon oxide (SiO _x , where 1 ≦ 1).
x ≦ 2) in a molar ratio of 50% or more.
= Refractive index for light of 520 nm is 1.44-1.48.
If there is no problem, MgF ₂ ,
Na ₃ AlF ₆ , LiF, CaF ₂ or the like may be mixed. The second and fourth layers have a wavelength λ = 52.
There is no problem as long as the refractive index for light of 0 nm is in the range of 1.90 to 2.20, and TiO ₂ , Nb ₂ O ₅ , Y ₂ O _3, etc. are mixed in addition to the ZrO ₂ : Ta ₂ O ₅ mixture. It doesn't matter. The third and fifth layers have a wavelength λ = 52.
There is no problem if the refractive index with respect to light of 0 nm is in the range of 1.35 to 1.40. In addition to MgF ₂ , SiO ₂ and Na ₃
AlF ₆ , LiF, CaF _{2 and the} like may be mixed.

(Comparative Example) The same glass substrates (a), (b) and (c) as those in the embodiment of the present invention were formed on the first glass substrate from the front side of the glass substrate by using the same film forming apparatus. Layer MgF
A material obtained by forming an anti-reflection film ₂ and the five layers, respectively and Comparative Examples 1. Table 6 shows the optical film thicknesses of the antireflection films of Comparative Examples 1, 2, and 3.

[0041]

[Table 6]

FIGS. 5 to 7 show the spectral reflectance characteristics of the antireflection films of Comparative Examples 1, 2, and 3, and Table 7 shows the reflectance with respect to typical wavelengths.

[0043]

[Table 7]

As shown in Table 7, the reflectance of the antireflection films of Comparative Examples 1, 2, and 3 was λ = 4 with respect to the wavelength λ of the incident light.
2% or less at 00 nm, 1 at 440 nm ≦ λ ≦ 650 nm
% And 2% or less at λ = 700 nm, all exhibit excellent reflectance characteristics. Further, for the antireflection films of Comparative Examples 1, 2, and 3, the appearance evaluation before and after the film formation, the cellophane tape peeling test for testing the adhesion of the film after the film formation, and the abrasion resistance were performed in the same manner as in the embodiment. Table 8 shows the results of the abrasion test.

[0045]

[Table 8]

According to Comparative Examples 1, 2, and 3, the scratches on the appearance were noticeable after the film formation, and appeared as burns and stains, and the appearance tended to be worse than before the film formation. Met. Further, in the cellophane tape peeling test and the abrasion test, bad results were obtained, such as peeling and scratching, as compared with the present embodiment.

According to the embodiment of the present invention, in forming an antireflection film on an optical component, a step of removing or preventing burns and scratches is not required before the film is formed, and the adhesion to the lens surface is high. Further, it is possible to obtain an antireflection film having good reflectance characteristics over a wide wavelength range of visible light and an optical component having the same.

[0048]

According to the first aspect of the present invention, it is possible to prevent burns and scratches generated on the surface of the optical component before forming the antireflection film.
Since it can be made inconspicuous, a step of removing or preventing burns and scratches before film formation becomes unnecessary, and cost can be reduced as compared with the conventional case. Further, since the adhesion between the optical component and the anti-reflection film is improved, the type of the optical component does not limit the anti-reflection film, and the applicable range can be expanded. In addition, each of the first to fifth layers has a wavelength of 5
By limiting the refractive index and the optical film thickness for the light of 20 nm, the reflectance of the antireflection film can have good reflectance characteristics over a wide wavelength range of visible light.

According to the second aspect of the present invention, the burns and scratches generated on the surface of the optical component can be made inconspicuous before the antireflection film is formed, so that the burns and scratches are removed before the film is formed. , Or the step of preventing it is unnecessary, and the cost can be reduced as compared with the conventional case. Further, since the adhesion between the optical component and the anti-reflection film is improved, the type of the optical component does not limit the anti-reflection film, and the applicable range can be expanded. Further, by forming the second layer and the fourth layer as high-refractive-index material layers made of a mixture containing at least zirconium oxide and tantalum oxide, an antireflection film having stable film quality can be obtained. Further, by setting the third and fifth layers to be low refractive index material layers made of a material containing at least magnesium fluoride, and by setting the optical film thickness of each layer to a specified range, the reflectance of the antireflection film can be improved. Can have good reflectance characteristics over a wide wavelength range of visible light.

According to the third aspect of the present invention, by forming the antireflection film of the first or second aspect on the surface of the optical component, burns and scratches are not noticeable, and the adhesion of the antireflection film is reduced. And an optical component having excellent reflectance characteristics over a wide wavelength range of visible light can be obtained.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a vacuum evaporation apparatus according to an embodiment of the present invention.

FIG. 2 is a table showing the spectral reflectance characteristics of the antireflection film of Example 1.

FIG. 3 is a table showing spectral reflectance characteristics of an antireflection film of Example 2.

FIG. 4 is a table showing the spectral reflectance characteristics of the antireflection film of Example 3.

FIG. 5 is a table showing the spectral reflectance characteristics of the antireflection film of Comparative Example 1.

FIG. 6 is a table showing spectral reflectance characteristics of an antireflection film of Comparative Example 2.

FIG. 7 is a table showing the spectral reflectance characteristics of the antireflection film of Comparative Example 3.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (reference) C23C 14/06 G02B 1/10 A F term (reference) 2K009 AA08 BB02 CC03 CC06 DD03 DD09 4F100 AA06D AA06E AA17C AA17E AA20B AA27C AA27E AG00A AT00A BA05 BA07 GB41 JN06 JN18B JN18C JN18D JN18E 4G059 AA11 AB11 AC04 GA02 GA04 GA12 4K029 AA09 BA42 BA43 BA46 BB02 BC07 CA01 DA03 DA12 DB14 DB21 FA03 FA04

Claims (3)

[Claims] A surface of an optical component made of optical glass,
In the antireflection film formed by laminating a plurality of materials, the first layer counted from the surface side of the optical component is made of a material containing silicon oxide in a molar ratio of 50% or more, and an mth layer (m = 1 to 1). Assuming that the refractive index for the light having a wavelength of 520 nm is 5 nm and the optical film thickness is nm dm, 14 ≦ n ₁ d ₁ ≦ 115 and 1.44 ≦ n ₁ ≦ 1.
48, 15 ≦ n ₂ d ₂ ≦ 71, 1.90 ≦ n ₂ ≦ 2.
20, 27 ≦ n ₃ d ₃ ≦ 74, 1.35 ≦ n ₃ ≦ 1.
40, 246 ≦ n ₄ d ₄ ≦ 318, 1.90 ≦ n ₄ ≦ 2.
20, 108 ≦ n ₅ d ₅ ≦ 147, 1.35 ≦ n ₅ ≦ 1.
40. An antireflection film, characterized by the following: 2. The surface of an optical component made of optical glass,
In the antireflection film formed by laminating a plurality of materials, the first layer counted from the surface side of the optical component is made of a material containing silicon oxide in a molar ratio of 50% or more, and has an optical thickness of 14 to 115 nm, the second layer is made of a mixture containing at least zirconium oxide and tantalum oxide, and has an optical thickness of 15 to
The third layer is made of a material containing at least magnesium fluoride, has an optical thickness of 27 to 74 nm, and the fourth layer is made of a mixture containing at least zirconium oxide and tantalum oxide. And its optical film thickness is 246.
The fifth layer is made of a material containing at least magnesium fluoride, and has an optical thickness of 108 to 147 nm.
An anti-reflection film characterized by the following. 3. The antireflection film according to claim 1 or 2,
An optical component characterized by having on its surface.