JPH10339808A - Reflection mirror - Google Patents

Abstract

(57) [Summary] A reflector having an arbitrary shape and having an absorption characteristic in an arbitrary wavelength band is manufactured. [MEANS FOR SOLVING PROBLEMS] Metal layers such as gold, silver, copper, and aluminum;
Single diameter polystyrene with a particle size of 5 nm to 100 μm, styrene / butadiene, polyvinyl toluene, styrene /
Polymer such as divinylbenzene, vinyltoluene / tertiary butylstyrene or non-metallic insulator microsphere layer such as silicon, silicon oxide, gallium arsenide, glass, etc., 1 nm to 100 nm thick formed by vapor deposition on these microspheres It has a three-layer structure of a layer of fine metal particles such as gold, silver, copper, and aluminum.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a reflecting mirror that absorbs light in a specific wavelength band and has a complicated curved surface.

[0002]

2. Description of the Related Art In the prior art, mirrors having different reflectances were produced by using a metal such as gold, silver, copper, or aluminum as a reflecting surface and appropriately selecting the thickness and type of the metal. In addition, a mirror having an arbitrary reflectance was manufactured by forming a dielectric multilayer film of an arbitrary thickness and material.

[0003]

In the above prior art, when a metal is used, it is impossible to manufacture a reflector having absorption characteristics in an arbitrary wavelength band, and a dielectric multilayer film is used. In this case, there is a problem that it is difficult to manufacture a reflecting mirror having a complicated curved surface because the film thickness must be strictly controlled.

An object of the present invention is to provide a method for easily manufacturing a reflector having an absorption characteristic in an arbitrary wavelength band and an arbitrary surface shape.

[0005]

In order to achieve the above object, the present invention utilizes absorption by fine metal particles. It is known that the absorption characteristics of metal fine particles due to surface plasmon depend on the shape, material, and particle size of the fine particles and are different from the bulk absorption characteristics. When adsorbed on the metal substrate via the spacer layer, the absorption increases due to the interaction between the localized surface plasmon of the metal fine particles and the surface plasmon of the metal substrate, and the peak of the absorption spectrum changes significantly depending on the particle size. This has recently turned out.

[0006] When a single layer of insulating microspheres having a uniform particle size is formed on a metal substrate, and a metal is vapor-deposited on the microsphere, fine particles become an insulator spacer layer, and the deposited metal is deposited on the microsphere. FIG. 1 (a)
As shown in (1), a reflecting mirror composed of three layers of a metal substrate 1, insulating microspheres 2 functioning as an insulating spacer layer, and metal fine particles 3 could be easily formed. The component in the specific wavelength band of the incident light 4 was absorbed and was specularly reflected as the reflected light 5. The reflection characteristics strongly depend on the type of metal to be deposited and the particle size of the insulating microspheres. When the reflecting mirror is made of gold, as shown in FIG. 1 (b), the reflectance obtained when using fine particles having a particle size of 100 nm is 6, and as shown in FIG. And the reflectance 8 obtained when microspheres having a particle size of 300 nm are used as shown in FIG.

The reflecting mirror of the present invention largely depends on the particle size, but the reflecting characteristics do not depend much on the thickness of the deposited film and the direction of the deposition. Therefore, it is possible to realize uniform absorption characteristics even on a curved surface. did it.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION

<Embodiment 1> An embodiment of the present invention will be described below with reference to FIG. A gold thin film 11 having a thickness of 5 nm to 1000 nm was formed on a flat silicon substrate 10 by vapor deposition. In order to make the surface of the gold thin film hydrophilic, a thiol solution containing a carboxylic acid such as sodium thioglycolate (concentration: 0.
(From 1 mM to 1 M), the gold thin film was treated with the thiol molecular layer 12 for 1 minute or more.

Next, the carboxylic acid of the thiol molecule is activated with a carbodiimide solution having a concentration of 0.01 mM to 1 M,
Polystyrene microspheres 13 having a particle size of 5 nm to 100 μm suspended in an aqueous solution were added to the surface to be adsorbed on the gold thin film surface. After drying, the gold is 5 to 100 nm thick
A reflective mirror was manufactured by forming gold fine particles 14 by vapor deposition. According to this embodiment, there is an effect that a reflecting mirror having an arbitrary reflecting characteristic can be easily manufactured by selecting microspheres having an appropriate particle diameter.

<Embodiment 2> An embodiment of the present invention will be described below with reference to FIG. A gold thin film 21 having a thickness of 5 nm to 1000 nm was formed on a flat glass substrate 20 by vapor deposition of gold. In order to make the surface of the gold thin film hydrophilic, the gold thin film is treated with a thiol solution having a carboxylic acid such as sodium thioglycolate (concentration of 0.01 mM to 1 M) for 1 minute or more, so that the surface of the gold thin film is a thiol molecular layer. 22 was chemically modified. Next, the carboxylic acid was activated with a carbodiimide solution having a concentration of 0.01 mM to 1 M, and the polystyrene A microspheres 23 having a particle size of 5 nm to 100 μm suspended in an aqueous solution.
And B microspheres 24 having different particle diameters, such as microspheres 24, were adsorbed on the surface of the gold thin film.

After drying, gold having a thickness of 5 nm to 100 nm is further vapor-deposited to form gold fine particles 25, so that the absorption 26 by the A microspheres 23 and the absorption by the B microspheres 24 as shown in FIG. Thus, a reflector having a wide wavelength band absorption characteristic 28 was manufactured. According to this embodiment, there is an effect that a reflecting mirror having an arbitrary broadband absorption characteristic can be easily manufactured, and the number of the adsorbed microspheres is not limited to two.

<Embodiment 3> An embodiment of the present invention will be described below with reference to FIG. As shown in FIG. 3A, a polymer substrate 30 having a paraboloid is formed by evaporation to a thickness of 5 nm to 100 nm.
A 0 nm silver thin film was formed. In order to make the surface of the silver thin film hydrophilic, the silver thin film is treated with a thiol solution having a carboxylic acid such as sodium thioglycolate (concentration of 0.01 mM to 1 M) for 1 minute or more, so that the surface of the silver thin film is a thiol molecular layer. Was chemically modified. Next, the carboxylic acid was activated with a carbodiimide solution having a concentration of 0.01 mM to 1 M, and polystyrene microspheres having a particle size of 5 nm to 100 μm suspended in an aqueous solution were added to the surface to be adsorbed on the surface of the silver thin film. After drying, silver having a thickness of 5 nm to 100 nm was further evaporated to produce a parabolic mirror 33 having a reflection surface 32 covered with an absorption film 31.

According to this embodiment, since a reflecting mirror having an arbitrary reflecting characteristic can be easily manufactured, conventionally, as shown in FIG. When necessary, a single reflecting mirror can be used instead, which has the effect of simplifying the optical system. According to the present embodiment, not only the paraboloid but also the complicated reflecting surface 4 as shown in FIG.
There is an effect that the reflecting mirror 41 having 0 can be easily manufactured.

<Embodiment 4> An embodiment of the present invention will be described below with reference to FIG. A gold thin film 51 having a thickness of 5 nm to 1000 nm was formed on a flat silicon substrate 50 by vapor deposition. In order to make the surface of the gold thin film hydrophilic, the gold thin film is treated with a thiol solution having a carboxylic acid such as sodium thioglycolate (concentration of 0.01 mM to 1 M) for 1 minute or more, and the surface of the gold thin film is treated with thiol molecules. The layer 52 was chemically modified. Next, the carboxylic acid of the thiol molecule is activated with a carbodiimide solution having a concentration of 0.01 mM to 1 M, and polystyrene microspheres 53 having a particle size of 5 nm to 100 μm suspended in an aqueous solution are added to the surface to be adsorbed on the gold thin film surface. did. After drying, gold was deposited to a thickness of 5 nm to 100 nm to form fine gold particles 54. In constructing the second-layer reflecting surface, the insulating thin film 55 is formed, and then the silver thin film 56, the microspheres 57, and the gold fine particles 5 are formed in the same manner as in the first layer.
A second reflective film composed of No. 8 was constructed. According to this embodiment, by selecting microspheres having an appropriate particle size in each reflective layer, there is an effect that a reflector having an arbitrary reflection characteristic can be easily manufactured.

[0015]

According to the present invention, it is possible to provide a method for manufacturing a reflector having absorption characteristics in an arbitrary wavelength band and having an arbitrary surface shape.

[Brief description of the drawings]

FIG. 1 is a diagram showing a principle configuration of the present invention and light reflection characteristics generated by metal microspheres formed on a substrate.

FIG. 2 is a sectional view showing a manufacturing process of the reflecting mirror according to one embodiment of the present invention.

FIG. 3 is a cross-sectional view of an example using a plurality of microspheres having different particle diameters and a diagram showing its light absorption characteristics.

FIG. 4 is a sectional view showing a reflecting mirror of an embodiment in which the functions of a reflecting mirror and an absorption filter are integrated, and a conventional example.

FIG. 5 is a sectional view of an embodiment in which an absorbing film is formed optically uniformly on a reflecting mirror having a complicated curved surface.

FIG. 6 is a sectional view showing a reflecting mirror of an embodiment having a plurality of reflecting layers.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Metal substrate, 2 ... Insulator microsphere, 3 ... Metal fine particle, 4
... incident light, 5 ... reflected light, 6 ... reflectivity obtained when using microspheres having a particle size of 100 nm, 7 ... reflectance obtained when using microspheres having a particle size of 200 nm, 8 ... microparticles having a particle size of 300 nm The reflectance obtained when using a sphere, 10 ... silicon substrate, 1
DESCRIPTION OF SYMBOLS 1 ... Gold thin film, 12 ... Thiol molecular layer, 13 ... Polystyrene microsphere, 14 ... Gold fine particle, 20 ... Glass substrate, 21 ...
Gold thin film, 22: thiol molecular layer, 23: A microsphere, 24
.. B microspheres, 25 ... gold fine particles, 26 ... absorption by A microspheres, 27 ... absorption by microspheres B, 28 ... wide wavelength band absorption characteristics, 30 ... polymer substrate having parabolic surface, 31 ... absorption film, 32: Reflecting surface, 33: Reflecting mirror, 34: Parabolic mirror without an absorbing film, 35: Absorbing filter, 40: Reflecting surface, 41
... reflecting mirror, 50 ... silicon substrate, 51 ... gold thin film, 52 ...
Thiol molecular layer, 53: polystyrene microspheres, 54: gold fine particles, 55: insulating thin film, 56: silver thin film, 57: microspheres, 58: silver fine particles.

Claims (3)

[Claims] 1. A metal layer of gold, silver, copper, aluminum or the like,
Single diameter polystyrene with a particle size of 5 nm to 100 μm, styrene / butadiene, polyvinyl toluene, styrene /
Polymer such as divinylbenzene, vinyltoluene / tertiary butylstyrene or non-metallic insulator microsphere layer such as silicon, silicon oxide, gallium arsenide, glass, etc., 1 nm to 100 nm thick formed by vapor deposition on these microspheres It has a three-layer structure of fine metal particles such as gold, silver, copper, and aluminum, so that it absorbs ultraviolet, visible, and infrared light in a wavelength band that depends on the particle size of the microspheres. mirror. 2. A reflecting mirror according to claim 1, wherein a plurality of types of polystyrene, styrene / butadiene, polyvinyltoluene, styrene / styrene having different particle sizes are provided on the insulating microsphere layer of the intermediate layer.
The absorption wavelength band is controlled by using a mixture of polymers such as divinylbenzene, vinyltoluene / tertiary butylstyrene, or non-metallic insulator microspheres such as silicon, silicon oxide, gallium arsenide, and glass. And a reflecting mirror. 3. A reflecting mirror according to claim 1, wherein said polymer is a polymer such as polystyrene, styrene / butadiene, polyvinyl toluene, styrene / divinylbenzene, vinyl toluene / tertiary butyl styrene or silicon, silicon oxide, gallium arsenide, glass or the like. A non-metallic insulator microsphere layer, gold deposited on these microspheres by evaporation,
A reflecting mirror having a hierarchical structure in which a plurality of layers of fine metal particles such as silver, copper, and aluminum are stacked.