JPH1073704A - Reflection mirror for high energy ray - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a reflection mirror for high energy rays having high reflectance characteristics, high heat resistance and excellent heat radiation property by forming an Al2 O3 layer on a base body of an aluminum nitride sintered body, forming a glass-mixed Al2 O3 layer prepared by mixing a glass in Al2 O3 on the Al2 O3 layer, and further forming a main glass layer and a laminated body thereon. SOLUTION: This reflection mirror is composed of a base body 11 of an aluminum nitride sintered body, an Al2 O3 layer 12 on the base body 11, a glass- mixed Al2 O3 layer 13 prepared by mixing a glass in Al2 O3 , a main glass layer 16 formed on the glass-mixed Al2 O3 layer 13, and a laminated body 17 produced by alternately depositing high refractive index layers 17a and low refractive index layers 17b on the main glass layer 16. By forming the high refractive index layer 17a which shows rather small absorption of light and is chemically stable on the low refractive index layer 17b, the reflection characteristics on the interface can be improved. By forming plural layers of these, the reflection efficiency can be improved.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a reflector used for reflecting light rays. More specifically, the present invention relates to a reflecting mirror for reflecting a high energy beam such as a laser beam.

[0002]

2. Description of the Related Art In recent years, the fields of application of high energy beams such as laser beams have been increasing. In particular, the field of activity of laser processing machines is expanding to ultra-precision processing such as drilling, cutting, and welding. Such a laser operates a laser beam by bending a laser beam generated from a laser beam source by a reflector or a prism. Conventionally, as a reflecting mirror that reflects such a high-energy light beam, a mirror in which a dielectric is formed in multiple layers on a substrate formed of an appropriate material such as a metal or an alloy such as aluminum or quartz glass is known. The surface of the substrate is mirror-polished, and the dielectric is formed on the substrate by a method such as an evaporation method or a sputtering method. By forming a laminate formed by alternately laminating such a high refractive index layer and a low refractive index layer a plurality of times on a substrate, a plurality of boundary surfaces can be provided. It can be increased to increase the reflection efficiency.

However, since a metal material such as aluminum has a property of causing an oxidation reaction, when used for a high-energy light beam, the oxidation reaction is accelerated by a temperature rise caused by reflection of the light beam. As a result, there was a problem that the laminate was peeled off and the reflectance was lowered. In addition, quartz glass has good workability and oxidation resistance is superior to aluminum, but the thermal conductivity of quartz glass itself is low. However, there was a problem that the reflectance was lowered due to peeling or thermal deformation of the substrate. In order to solve these problems, a reflector using a ceramic such as Si or SiC having a relatively high thermal conductivity for a substrate is known. By using such a substrate, a reflection mirror having high oxidation resistance and good heat resistance can be manufactured.

[0004]

However, Si is excellent in thermal conductivity, but mechanical strength is weaker than aluminum or quartz glass, so it can be used for mirror-polishing the surface and handling for forming the dielectric layer. There is a problem that it causes difficulty and cannot be used in a place where mechanical strength is required. Also,
SiC has a higher mechanical strength than Si and does not cause any trouble in Si, but has a problem that the workability in mirror polishing is inferior due to the increase in mechanical strength. That is, due to the difficulty of mirror polishing, an excessive time is required as compared with a normal processing time for processing Si or the like. There is a problem that it is difficult to finish the flatness. An object of the present invention is to provide a high-energy ray reflecting mirror having high reflectance characteristics and high heat resistance and excellent heat dissipation.

[0005]

The invention according to claim 1 is
As shown in the enlarged view of FIG. 1, a base 11 made of an aluminum nitride sintered body, and a glass mixture A in which glass is mixed with Al ₂ O ₃ provided on the base 11 with an Al ₂ O ₃ layer 12 interposed therebetween.
l ₂ O ₃ layer 13, a main glass layer 16 provided on the glass-mixed Al ₂ O ₃ layer 13, and a high refractive index layer 17 a and a low refractive index layer 17 b on the main glass layer 16 alternately. A high-energy ray reflecting mirror 10 including a laminated body 17 formed by laminating a plurality of times. Although not shown, another configuration of the reflecting mirror 10 is a glass mixed the Al ₂ O ₃ layer glass are mixed in Al ₂ O ₃ on a substrate made of an aluminum nitride sintered body is formed directly.

In the reflecting mirror 10, the Al ₂ O ₃ layer 12 has a high consistency with the sintered body at the interface with the sintered body 11 and is firmly joined to the base 11. This Al ₂ O ₃ layer 12
Functions as a glass barrier layer for the substrate 11 and prevents the generation of bubbles at the interface of the substrate 11. Further, since the Al ₂ O ₃ layer formed by thermal oxidation is porous, it has the following features. That is, the coefficient of thermal expansion is (7-8) × 10 ⁻⁶ /
Since the thermal expansion coefficient of aluminum nitride is as small as about 4 × 10 ⁻⁶ / ° C. as compared with Al ₂ O _{3 at} ° C., glass mixed Al ₂ O formed by intrusion of glass into the porous Al ₂ O ₃ layer ₃ layers 13
Is smaller if the coefficient of thermal expansion than the thermal expansion coefficient of the thermal expansion coefficient of the glass is Al ₂ O ₃ approaches the aluminum nitride can sufficiently relax the thermal stress generated during the heat treatment at the time of layer formation, Al ₂ O _No cracks occur in the _three layers 13.

The invention according to claim 2 is the invention according to claim 1, wherein the Al ₂ O ₃ layer 12 is formed to a thickness of 0 to 9.99 μm, and the glass-mixed Al ₂ O ₃ layer 13 is .01-1
The main glass layer 16 is formed to a thickness of 0 μm.
The high refractive index layer 17a is formed to a thickness of
The low refractive index layer 17b is formed to have a thickness of 60 nm to 300 nm. In particular, the main glass layer 16 is preferably formed to have a thickness of 2 μm to 40 μm. When the thickness of the main glass layer 16 is less than 0.1 μm, the surface smoothness of the substrate is not sufficient, and as a result, it is difficult to obtain a high reflectance, and
If it exceeds m, there is a problem that the thermal conductivity of the entire substrate is extremely reduced. In addition, the high refractive index layer 17a and the low refractive index layer 17
b is 30 nm or more depending on the use of the high energy beam reflecting mirror.
It is preferably formed to a thickness of 150 nm and a thickness of 60 nm to 300 nm, respectively. If the thicknesses of the high refractive index layer 17a and the low refractive index layer are out of the above ranges, a sufficient reflectance cannot be obtained.

[0008] According to a third aspect of the present invention, as shown in the enlarged view of FIG.
Al is provided on the substrate 11 with an Al ₂ O ₃ layer 12 interposed therebetween.
Glass mix the Al ₂ O ₃ layer 13 in which the glass are mixed in ₂ O _3,
The glass mix the Al ₂ O ₃ layer 13 provided on the Al ₂ O _3,
An oxide particle-dispersed glass layer 14 in which one or two or more oxide particles selected from the group consisting of TiO ₂ and ZrO ₂ particles are dispersed in glass;
Main glass layer 1 provided thereon and not containing the oxide particles
6 is a high-energy ray reflecting mirror 20 including a main body layer 16 and a laminated body 17 formed by alternately laminating a high refractive index layer 17a and a low refractive index layer 17b on the main glass layer 16 a plurality of times.
Although not shown, another configuration of the reflecting mirror 20 does not include the Al ₂ O ₃ layer 12 like the reflecting mirror 10 of another configuration.

In the reflecting mirror 20, the oxide particle-dispersed glass layer 14 is formed by dispersing particles such as Al ₂ O ₃ , TiO ₂ , and ZrO _{2 having} better heat conductivity than glass in the glass layer.
The heat conductivity of the layer 14 is increased, and the heat radiation characteristics of the reflecting mirror 20 are further improved. The oxide particle-dispersed glass layer 14
Formation improves the surface smoothness of the glass-mixed Al ₂ O ₃ layer. This means that even with an aluminum nitride sintered body having a relatively large surface roughness, it is possible to reduce the substrate surface roughness and improve the substrate surface smoothness. The surface of the laminate 17 formed on the smoothed main glass layer has a mirror surface without distortion.

The invention according to claim 4 is the invention according to claim 3, wherein the Al ₂ O ₃ layer 12 is formed to a thickness of 0 to 9.99 μm, and the glass-mixed Al ₂ O ₃ layer 13 is .01-1
Oxide particle-dispersed glass layer 14 formed to a thickness of 0 μm.
Is formed to a thickness of 0.1 to 10 μm, and the main glass layer 16 is formed.
Is formed to a thickness of 0.1 to 100 μm, and the high refractive index layer 1
7a is formed to a thickness of 30 nm to 150 nm, and the low refractive index layer 17b is formed to a thickness of 60 nm to 300 nm.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS First, points common to the reflecting mirrors according to claims 1 and 3 will be described. The aluminum nitride sintered body serving as the base of the present invention is not limited to a sintered body consisting of only aluminum nitride alone, but is a sintered body containing aluminum nitride as a main component and various additives such as CaO and Y ₂ O _3. It may be your body. Al ₂ O ₃ provided on this substrate
The layer is formed by heating the aluminum nitride sintered body at 1100-1500 ° C. in an atmosphere having an oxygen partial pressure of 1 × 10 ⁻² atm or more and a steam partial pressure of 1 × 10 ⁻³ atm or less.
It is made by heat treatment for about 0.5 hour. The higher the temperature, the shorter the processing time may be. By this heat treatment, the surface of the aluminum nitride sintered body is oxidized to have a porosity of 0.
01-15 volume% of Al ₂ O ₃ layer is formed.

(A) The reflecting mirror according to claim 1 The glass-mixed Al ₂ O ₃ layer and the main glass layer on the substrate before forming a laminate composed of the high refractive index layer and the low refractive index layer of the reflecting mirror , and fired after the glass particles are dispersed suspension was applied and dried in a solvent the Al ₂ O ₃ layer on made by the thermal oxidation, Al ₂ O ₃ by heat treatment at a temperature at which the glass softens
It is made by penetrating softened glass into the micropores at the top of the layer. It is necessary to prevent the softened glass from reaching the aluminum nitride sintered body when invading the glass. In other words, it is necessary to leave the Al ₂ O ₃ layer on the aluminum nitride sintered body. This is because bubbles are not generated at the interface of the sintered body due to the reaction between the glass and the sintered body. As shown in the enlarged view of FIG. 1, in this reflecting mirror 10, an Al ₂ O ₃ layer 1 formed by oxidation and not penetrated by glass is formed on a substrate 11 made of a sintered body.
2, a glass mixed the Al ₂ O ₃ layer 13 in which the glass in Al ₂ O ₃ glass from entering are mixed, a main glass layer 16, a multilayer body 17 made of a high refractive index layer and a low refractive index layer is the They are formed in order. Here, the glass-containing Al ₂ O ₃ layer 13 preferably contains 0.01 to 15% by volume of glass according to the porosity of the Al ₂ O ₃ layer formed by thermal oxidation.

The high refractive index layer 17a and the low refractive index layer 17b of the laminate formed on the main glass layer 16 are formed by a sputtering method, a vapor deposition method or the like. High refractive index layer 17
Examples of a include ZnS (zinc sulfide), TiO ₂ (titanium dioxide), CeO ₂ (cerium dioxide), and the like. Z
nS and TiO ₂ form a fairly hard and fairly durable film without light absorption in the visible spectrum, while CeO ₂ forms a more chemically stable film. Examples of the low refractive index layer 17b include MgF ₂ (magnesium fluoride), ThF ₂ (thorium fluoride), and the like. M
Similarly, gF ₂ and ThF ₂ form an extremely hard and durable film without light absorption in the visible spectrum.

Since the reflection of light rays mainly occurs at the interface of the refractive index, the reflection occurring at different interfaces has almost no reflection loss due to absorption, and can be a very good reflecting surface. Therefore, it is necessary to form the chemically stable high refractive index layer 17a, which has relatively little light absorption, on the chemically stable low refractive index layer 17b, which does not normally absorb light. Accordingly, the reflection characteristics at the boundary surface can be improved, and the reflection efficiency can be improved by providing a plurality of such layers 17a and 17b. However, the film thickness of these layers 17a and 17b needs to be selected in consideration of the intended use. That is, each layer 17
The light reflected from the boundary surfaces a and 17b is reflected while overlapping each other. Therefore, when the phases of the light overlap, the light reinforces each other, and when the phase is inverted, the light cancels out. Therefore, the reflectivity can be increased by adjusting the film thickness according to the wavelength and the incident angle of the light beam to be reflected, and sequentially increasing the number of boundary surfaces by laminating a plurality of times. This laminate 17 is made of a high refractive index layer 17.
It is preferable to form at least two layers each of a and the low refractive index layer 17b. If it is less than two layers, it will be difficult to obtain a sufficient reflectance.

In this reflector, the Al ₂ O ₃ layer formed by the above thermal oxidation is impregnated with an alkoxide or a sol as a glass precursor, and baked to fix glass in the Al ₂ O ₃ layer. It is also made by letting them do. In this case, it is not necessary to leave the Al ₂ O ₃ layer 12 in which glass has not penetrated, and air bubbles are not generated at the bonding interface between the sintered body 11 and the glass-containing Al ₂ O ₃ layer 13. Al
_A reflector 10 without the ₂ O ₃ layer 12 is made. This method can be similarly applied to a reflecting mirror 20 according to claim 3 described later.

(B) Reflector according to claim 3 The reflector 20 shown in the enlarged view of FIG. 2 is manufactured by the following method.
Can be First, Al made by thermal oxidation_TwoO_ThreeGala on layer
The suspension in which the particles are dispersed in the solvent
After coating, drying and firing, the above Al_TwoO_Threelayer
The softened glass penetrates into the fine pores of_TwoO_Threelayer
From the base 11 side of the sintered body_TwoO_ThreeLayer 12
And glass mixed Al_TwoO_ThreeLayer 13. Then this glass
Mixed Al _TwoO_ThreeAl on the layer 13_TwoO_Three, TiO_TwoAnd ZrO_Two
One or more oxides selected from the group consisting of particles
Apply and dry suspension of particles and glass particles dispersed in solvent
After firing, the glass particles are softened
To form a glass layer 14 in which the oxide particles are dispersed.
You. Further, glass particles are formed on the oxide particle-dispersed glass layer 14.
Apply the suspension in which the particles are dispersed in the solvent, dry and bake.
Thereby, the glass particles are softened to form the main glass layer 16.
To form

The reflecting mirror 20 shown in the enlarged view of FIG. 2 can be made by the following alternative method. First, Al ₂ O ₃ made by thermal oxidation
One or two or more oxide particles selected from the group consisting of Al ₂ O ₃ , TiO ₂ and ZrO ₂ particles and a suspension of SiO ₂ particles dispersed in a solvent are applied on the layer, dried and fired. To form a composite or mixed layer of oxide particles and SiO ₂ particles. Subsequently, a suspension in which glass particles are dispersed in a solvent is applied onto the composite or mixed layer, and dried to form a glass particle layer. Finally, heat treatment is performed at a temperature at which the glass particle layer softens, and the softened glass of the glass particle layer dissolves the SiO ₂ particles of the composite or mixed layer, and further melts the porous Al ₂
Penetrates into the O ₃ layer. As a result, as shown in FIG. 2, a four-layer structure of an Al ₂ O ₃ layer 12, a glass-mixed Al ₂ O ₃ layer 13, an oxide particle dispersed glass layer 14, and a main glass layer 16 on a sintered body 11 is formed. Is formed, and the main glass layer 1
A laminate 17 is formed on 6. Also in this case, it is necessary to control the softening conditions of the glass layer so that the softened glass does not reach the aluminum nitride sintered body. In other words,
It is necessary to leave the Al ₂ O ₃ layer on the aluminum nitride sintered body. Al ₂ O ₃ mixed with glass for reflector 20
The layer 13 contains 0.01 to 15% by volume of glass depending on the porosity of the Al ₂ O ₃ layer formed by thermal oxidation, and the oxide particle-dispersed glass layer 14 contains 5 to 100% by volume of glass. % Is preferably contained. The thickness of each layer is
This is the same as the case of the reflecting mirror 10 except that the oxide particle dispersed glass layer 14 is formed to a thickness of 0.1 to 10 μm.

The main glass layers of the reflectors 10 and 20;
The glass component in the oxide particle-dispersed glass layer and the glass-mixed Al ₂ O ₃ layer is PbO—SiO ₂ —B ₂ O ₃ based on Al.
_This is a system to which ₂ O ₃ , an alkaline earth metal, an alkali metal and the like are added. This glass layer has a thermal expansion coefficient of A
It is preferable that the coefficient of thermal expansion is close to 1N because defects such as cracks do not occur when these layers are formed. Specifically, the thermal expansion coefficient of these layers is preferably (4.4 ± 1.0) × 10 ⁻⁶ / ° C. close to the thermal expansion coefficient of AlN. In addition, this glass layer is formed by mixing these glass powders with a solvent to form a glass paste, and applying the glass paste to an Al ₂ O ₃ layer formed by thermal oxidation, such as screen printing, spray coating, dip coating, and spin coating. After coating and drying by the method, it is formed by firing. Further, the glass layer may be formed by applying a glass paste to a plastic base sheet and then peeling the base sheet by stacking the paste surface of the sheet on the surface to be laminated, a sol-gel method, a sputtering method, or the like.

[0019]

Next, embodiments of the present invention will be described. Example 1 The reflecting mirror 10 shown in FIG. 1 was manufactured by the following method. First, the surface roughness is 0.5 to 0.
A flat aluminum nitride sintered substrate having a thickness of 6 μm,
Heat treatment was performed at 1300 ° C. for 1 hour in the air to form a 3.0 μm thick porous Al ₂ O ₃ layer on the surface of the sintered substrate. Next, a suspension in which glass particles were uniformly dispersed in a solvent was applied on the Al ₂ O ₃ layer by a spray coating method.
It dried at 30 degreeC for 30 minutes, and formed the glass particle layer. Subsequently, it was baked at 1000 ° C. for 30 minutes to soften the glass of the glass particle layer. Thus, the Al ₂ O ₃ layer 12 and the glass-mixed Al are placed on the plane of the substrate 11 made of the aluminum nitride sintered body.
_{The 2} O ₃ layer 13 and the main glass layer 16 were formed in this order.
On this main glass layer 16, a ZnS thin film as a high refractive index layer having a thickness of 60 nm and Mg as a low refractive index layer having a thickness of 100 nm are formed.
And F ₂ are alternately laminated five times by a vacuum evaporation method to a thickness of 80
A laminate 17 having a thickness of 0 nm was formed.

Embodiment 2 The reflecting mirror 20 shown in FIG. 2 was manufactured by the following method. First, a flat aluminum nitride sintered body having the same surface roughness as that of Example 1 was placed in the air.
Heat treated at 1300 ° C for 1 hour, and apply 3.0μ
An m-thick porous Al ₂ O ₃ layer was formed. Al ₂ O ₃ particles and S
iO ₂ particles and the Al ₂ O ₃ particles 34% by weight, after preparing a suspension of SiO ₂ particles are uniformly dispersed in a solvent at a ratio of 66 wt%, the porous Al ₂ O The suspension _{After the three} layers were applied by a spray coating method, they were dried at 300 ° C. for 1 hour and then fired at 1100 ° C. for 1 hour to form a composite or mixed layer of Al ₂ O ₃ particles and SiO ₂ particles. Next, a suspension in which glass particles were uniformly dispersed in a solvent was applied on the composite or mixed layer by a spray coating method, and dried at 150 ° C. for 30 minutes to form a glass particle layer. Subsequently, it was baked at 1000 ° C. for 30 minutes to soften the glass of the glass particle layer. As a result, Al is placed on the plane of the substrate 11 made of the aluminum nitride sintered body.
_{The 2} O ₃ layer 12, the glass-containing Al ₂ O ₃ layer 13, the oxide particle dispersed glass layer 14, and the main glass layer 16 were formed in this order. A laminate 17 having a thickness of 800 nm was formed on the main glass layer 16 in the same manner as in Example 1.

<Comparative Example 1> An aluminum nitride sintered substrate having the same plane as in Example 1 was not heat-treated and was directly 800 nm thick on the substrate surface by the same method as in Example 1.
Was formed. <Comparative Example 2> A suspension in which the same glass particles as in Example 1 were uniformly dispersed in a solvent was sprayed directly on the surface of the aluminum nitride sintered substrate having the same plane as in Example 1 without heat treatment. It was applied by a coating method and dried at 150 ° C. for 30 minutes to form a glass particle layer. Then 10
The glass of the glass particle layer was softened by baking at 00 ° C. for 30 minutes. Thus, a glass layer was formed on the plane of the substrate made of the aluminum nitride sintered body. On this glass layer, a laminate having a thickness of 800 nm was formed in the same manner as in Example 1.

<Comparative Test and Evaluation>
For the reflecting mirrors of Comparative Example 1 and Comparative Example 2, the reflectivity of the high-energy light beam was compared and tested. Table 1 shows the results. The reflectance is 550 nm for the laminate on the substrate.
Is determined by measuring the total reflectance when irradiating a light beam with a spectrophotometer, and the heat resistance of the laminate after aging at 500 ° C. for 100 hours in the air at 500 ° C. Was visually determined for any change in appearance. Further, the adhesion of the laminate to the substrate was evaluated by the peeling (peeling) test of the laminate after the above-mentioned aging treatment, and the peeled or broken portion was determined.

[0023]

[Table 1]

As is clear from Table 1, Comparative Example 1 having no glass layer had a reflectivity of 78% and had a glass layer but did not have an Al ₂ O ₃ layer and a glass-mixed Al ₂ O ₃ layer. In Example 2, the reflectance was 70%. On the other hand, in Examples 1 and 2 having the Al ₂ O ₃ layer, the glass-mixed Al ₂ O ₃ layer and the glass layer on the substrate, the reflectance was 98%. In addition, the reflective mirror of Comparative Example 2 caused fine swelling due to the high heat treatment, whereas the laminates of Examples 1 and 2 showed no change and exhibited high heat resistance. Further, in the peeling test, peeling occurred between the laminate and the substrate with the reflecting mirror of Comparative Example 1, and between the glass layer and the substrate with the reflecting mirror of Comparative Example 2, whereas the reflecting mirrors of Examples 1 and 2 produced the substrate. It was peeling inside.

[0025]

As described above, according to the reflector of the present invention, even if the surface roughness of the sintered body is large, the glass mixed Al
₂ O ₃ layer and main glass layer, or glass mixed Al ₂ O ₃ layer,
The oxide particle-dispersed glass layer and the main glass layer flatten this, and the surface of the laminate formed on the main glass layer is made a mirror surface without distortion. In addition, since the laminate is formed on the base made of the aluminum nitride sintered body via the main glass layer, the laminate has high heat resistance and heat dissipation. In particular, the present invention exerts excellent effects on reflectance characteristics and heat resistance as compared with conventional reflecting mirrors.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a reflecting mirror of the present invention and an enlarged sectional view thereof.

FIG. 2 is a sectional view corresponding to FIG. 1 and showing another reflecting mirror of the present invention.

[Explanation of symbols]

10, 20 reflector 11 base 12 the Al ₂ O ₃ layer 13 of glass mixed the Al ₂ O ₃ layer 14 oxide particle dispersion glass layer 16 main glass layer 17 laminated body 17a high refractive index layer 17b low refractive index layer

Claims (4)

[Claims] 1. A base (1) made of an aluminum nitride sintered body.
1) and an Al ₂ O ₃ layer (12) on the substrate (11) or A
a glass-mixed Al ₂ O ₃ layer (13) in which glass is mixed with Al ₂ O ₃ , which is provided without passing through the l ₂ O ₃ layer (12);
The main glass layer (16) provided on the l ₂ O ₃ layer (13), and the high refractive index layer (17a) and the low refractive index layer (17b) are alternately formed on the main glass layer (16). A high-energy ray reflecting mirror comprising: a laminate (17) formed by multiple laminations. 2. An Al ₂ O ₃ layer (12) having a thickness of 0 to 9.99 μm and a glass-mixed Al ₂ O ₃ layer (13) having a thickness of 0.01 to 9.99 μm.
The main glass layer (16) is formed to a thickness of 10 μm,
The high refractive index layer (17a) is formed to a thickness of 100 μm and has a thickness of 30 μm.
nm-150 nm thick, low refractive index layer (17b)
2. The reflector for a high-energy light beam according to claim 1, wherein is formed to a thickness of 60 nm to 300 nm. 3. A base (1) made of an aluminum nitride sintered body.
1) and an Al ₂ O ₃ layer (12) on the substrate (11) or A
a glass-mixed Al ₂ O ₃ layer (13) in which glass is mixed with Al ₂ O ₃ , which is provided without passing through the l ₂ O ₃ layer (12);
Al ₂ O ₃ , TiO ₂ and Zr provided on the l ₂ O ₃ layer (13)
An oxide particle-dispersed glass layer (1) in which one or more oxide particles selected from the group consisting of O ₂ particles are dispersed in glass.
4), a main glass layer (16) provided on the oxide particle dispersed glass layer (14) and not containing the oxide particles, and a high refractive index layer (17a) on the main glass layer (16) And a low-refractive-index layer (17b). 4. An Al ₂ O ₃ layer (12) having a thickness of 0 to 9.99 μm and a glass-mixed Al ₂ O ₃ layer (13) having a thickness of 0.01 to 9.99 μm.
An oxide particle-dispersed glass layer (1
4) is formed to a thickness of 0.1 to 10 μm, and the main glass layer (1
6) is formed to a thickness of 0.1 to 100 μm, and has a high refractive index layer
The high-energy ray reflecting mirror according to claim 3, wherein (17a) is formed with a thickness of 30 nm to 150 nm, and the low refractive index layer (17b) is formed with a thickness of 60 nm to 300 nm.