JP2005107046A - Lenticular lens for display - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lenticular lens for display equipped with an advanced antireflection function whose transmittance to all the light beams is high. <P>SOLUTION: In the lenticular lens for display 2, an antireflection film 6 is formed on at least either surface of base material 4 by supplying gas containing thin film forming gas to discharge space and applying high frequency electric field to the discharge space under atmospheric pressure or pressure near it, so that the gas is excited, and exposing the base material 4 to the excited gas. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a lenticular lens constituting a display device, and more particularly to a lenticular lens for display having an antireflection film formed thereon.

  A normal transmission type screen has a configuration in which two screens, a Fresnel lens and a lenticular lens, are stacked (see, for example, Patent Document 1). In the lenticular lens, light diffusing fine particles made of glass or a polymer member are mixed in a base material, and both surfaces have a cylindrical shape. In addition, a projection-like external light absorbing layer (black stripe) is formed in a stripe shape at a predetermined pitch on the non-condensing part on the light incident side of both surfaces of the lenticular lens. It is possible to prevent a decrease in contrast due to.

  By the way, in the above lenticular lens, in general, a part of the light diffusing fine particles protrudes on the surface of the cylindrical portion or the black stripe portion, but in such a configuration, the surface of the lenticular lens is uneven. When external light is irradiated on the light exit surface of the lenticular lens, there is a problem that the external light is irregularly reflected on the light exit surface and the screen surface becomes whitish, resulting in deterioration of contrast.

In order to prevent the sharpness of the image projected on the screen and the decrease in contrast due to outside light, there is a method of placing a transparent panel made of glass or plastic with reduced light transmittance on the front of the screen. However, there is a problem that it is difficult to see the image on the screen because the reflection of external light (such as lighting equipment and viewers) on the transparent panel is extremely generated.
Japanese Patent Laid-Open No. 6-160982

In such a situation, it is possible to prevent the sharpness of the image projected on the screen and the decrease in contrast due to external light by forming an antireflection film on the surface of the lenticular lens. Is required to have a high total light transmittance and an advanced antireflection function. As a technique for forming an antireflective film on a lenticular lens, a known coating technique can be mentioned. However, when an antireflective film is formed by a coating technique, uneven coating is formed on the antireflective film and the film thickness is made uniform. Therefore, it is impossible to form an antireflection film having a high total light transmittance and an advanced antireflection function on the surface of the lenticular lens.
An object of the present invention is to provide a lenticular lens for display having a high total light transmittance and an advanced antireflection function.

In order to solve the above problem, the invention according to claim 1
A gas containing a thin film forming gas is supplied to the discharge space under atmospheric pressure or a pressure in the vicinity thereof, the high-frequency electric field is applied to the discharge space to excite the gas, and the substrate is exposed to the excited gas. A lenticular lens for display in which an antireflection film is formed on at least one surface of the substrate,
The high-frequency electric field is a superposition of the first high-frequency electric field and the second high-frequency electric field, and the frequency ω2 of the second high-frequency electric field is higher than the frequency ω1 of the first high-frequency electric field, and the first high-frequency electric field is And the second high frequency electric field strength V2 and the discharge start electric field strength IV satisfy V1 ≧ IV> V2 or V1> IV ≧ V2, and the output density of the second high frequency electric field is Is 1 W / cm ² or more.

The invention according to claim 2 is the lenticular lens for display according to claim 1,
The discharge space includes a first electrode and a second electrode facing each other.

The invention described in claim 3 is the lenticular lens for display according to claim 1 or 2,
The output density of the second high frequency electric field is 50 W / cm ² or less.

The invention according to claim 4 is the lenticular lens for display according to claim 3,
The output density of the second high-frequency electric field is 20 W / cm ² or less.

The invention according to claim 5 is the lenticular lens for display according to any one of claims 1 to 4,
The output density of the first high frequency electric field is 1 W / cm ² or more.

The invention described in claim 6 is the lenticular lens for display according to claim 5,
The output density of the first high-frequency electric field is 50 W / cm ² or less.

The invention according to claim 7 is the lenticular lens for display according to any one of claims 1 to 6,
The first high-frequency electric field and the second high-frequency electric field are sine waves.

The invention according to claim 8 is the lenticular lens for display according to any one of claims 2 to 7,
The first high-frequency electric field is applied to the first electrode, and the second high-frequency electric field is applied to the second electrode.

The invention according to claim 9 is the lenticular lens for display according to any one of claims 1 to 8,
90-99.9 volume% of the total gas amount supplied to the discharge space is a discharge gas.

The invention described in claim 10 is the lenticular lens for display according to claim 9,
The discharge gas contains 50 to 100% by volume of nitrogen gas.

The invention according to claim 11 is the lenticular lens for display according to claim 9 or 10,
The discharge gas contains a rare gas of less than 50% by volume.

The invention according to claim 12 is the lenticular lens for display according to any one of claims 1 to 11,
The thin film forming gas contains at least one selected from an organometallic compound, a metal halide, and a metal hydride.

The invention according to claim 13 is the lenticular lens for display according to claim 12,
The organometallic compound contains at least one compound selected from an organosilicon compound, an organotitanium compound, an organotin compound, an organozinc compound, an organoindium compound, and an organoaluminum compound.

The invention according to claim 14 is the lenticular lens for display according to any one of claims 1 to 13,
The thickness of the base material is 1 mm or more.

The present invention is described in detail below.
In the present invention, the plasma discharge treatment is performed under atmospheric pressure or a pressure in the vicinity thereof, and “atmospheric pressure or the pressure in the vicinity thereof” is about 20 kPa to 110 kPa, and the favorable effects described in the present invention are obtained. Therefore, 93 kPa to 104 kPa is preferable.

  In the present invention, the gas supplied between the counter electrodes (discharge space) includes at least a discharge gas excited by an electric field and a thin film forming gas that receives the energy and forms a thin film in a plasma state or an excited state. .

  However, in the present invention, in rare gas discharge gases such as helium and argon, the production cost when forming a thin film often depends on the cost of the discharge gas, and the use of an alternative discharge gas also from an environmental standpoint. The present inventors have studied. As a result of investigating air, oxygen, nitrogen, carbon dioxide, hydrogen, etc. as alternative discharge gases, it is necessary to obtain conditions that can generate high-density plasma even with these gases, and it has excellent thin film formability and formation. As a result of studying conditions and methods for making the thin film dense and uniform, the present invention has been achieved.

The discharge condition in the present invention is such that the first high-frequency electric field and the second high-frequency electric field are superimposed on the discharge space, and the frequency ω2 of the second high-frequency electric field is higher than the frequency ω1 of the first high-frequency electric field, In addition, the relationship between the first high-frequency electric field strength V1, the second high-frequency electric field strength V2, and the discharge start electric field strength IV satisfies V1 ≧ IV> V2 or V1> IV ≧ V2. The power density of the second high frequency electric field is 1 W / cm ² or more.

High frequency refers to one having a frequency of at least 0.5 kHz.
When the superposed high-frequency electric field is both a sine wave, the frequency ω1 of the first high-frequency electric field and the frequency ω2 of the second high-frequency electric field higher than the frequency ω1 are superimposed, and the waveform is a sine of the frequency ω1. A sawtooth waveform in which a sine wave having a higher frequency ω2 is superimposed on the wave is obtained.

  In the present invention, the strength of the electric field at which discharge starts is the lowest electric field intensity that can cause discharge in the discharge space (such as electrode configuration) and reaction conditions (such as gas conditions) used in the actual thin film formation method. Point to. The discharge start electric field strength varies somewhat depending on the type of gas supplied to the discharge space, the dielectric type of the electrode, or the distance between the electrodes, but is controlled by the discharge start electric field strength of the discharge gas in the same discharge space.

  By applying a high-frequency electric field as described above to the discharge space, it is presumed that a discharge capable of forming a thin film is generated and high-density plasma necessary for forming a high-quality thin film can be generated.

  What is important here is that such a high-frequency electric field is applied to the opposing electrodes, that is, applied to the same discharge space. As described in Japanese Patent Application Laid-Open No. 11-16696, the thin film formation of the present invention cannot be achieved by a method in which two application electrodes are juxtaposed and different high-frequency electric fields are applied to the different discharge spaces.

  Although the superposition of continuous waves such as sine waves has been described above, the present invention is not limited to this, and both pulse waves may be used, one of them may be a continuous wave and the other may be a pulse wave. Further, it may have a third electric field.

  As a specific method of applying the high-frequency electric field of the present invention to the same discharge space, the first high-frequency electric field having the frequency ω1 and the electric field strength V1 is applied to the first electrode constituting the counter electrode. It is to use an atmospheric pressure plasma discharge treatment apparatus in which a power source is connected and a second power source for applying a second high frequency electric field having a frequency ω2 and an electric field strength V2 is connected to the second electrode.

  The atmospheric pressure plasma discharge treatment apparatus includes a gas supply unit that supplies a discharge gas and a thin film forming gas between the counter electrodes. Furthermore, it is preferable to have an electrode temperature control means for controlling the temperature of the electrode.

  Further, it is preferable to connect the first filter to the first electrode, the first power source or any of them, and connect the second filter to the second electrode, the second power source or any of them, The first filter facilitates the passage of the first high-frequency electric field current from the first power source to the first electrode, grounds the second high-frequency electric field current, and the second filter from the second power source to the first power source. It makes it difficult to pass the current of the high frequency electric field. On the other hand, the second filter makes it easy to pass the current of the second high-frequency electric field from the second power source to the second electrode, grounds the current of the first high-frequency electric field, and the second power from the first power source. A power supply having a function of making it difficult to pass the current of the first high-frequency electric field to the power supply is used. Here, being difficult to pass means that it preferably passes only 20% or less of the current, more preferably 10% or less. On the contrary, being easy to pass means preferably passing 80% or more of the current, more preferably 90% or more.

  Furthermore, it is preferable that the first power source of the atmospheric pressure plasma discharge processing apparatus of the present invention has a capability of applying a higher frequency electric field strength than the second power source.

  Here, the high frequency electric field strength (applied electric field strength) and the discharge starting electric field strength referred to in the present invention are those measured by the following method.

Measuring method of high-frequency electric field strengths V1 and V2 (unit: kV / mm):
A high-frequency voltage probe (P6015A) is installed in each electrode section, and the output signal of the high-frequency voltage probe is connected to an oscilloscope (Tektronix, TDS3012B), and the electric field strength is measured.

Measuring method of electric discharge starting electric field intensity IV (unit: kV / mm):
A discharge gas is supplied between the electrodes, the electric field strength between the electrodes is increased, and the electric field strength at which discharge starts is defined as a discharge starting electric field strength IV. The measuring instrument is the same as the high frequency electric field strength measurement.

  The positional relationship between the high-frequency voltage probe used for the measurement and the oscilloscope is shown in FIG.

  By adopting the discharge conditions specified in the present invention, even a discharge gas having a high discharge starting electric field strength, such as nitrogen gas, can start discharge, maintain a high density and stable plasma state, and form a high-performance thin film. It can be done.

When the discharge gas is nitrogen gas by the above measurement, the discharge start electric field strength IV (1/2 V _pp ) is about 3.7 kV / mm. Therefore, in the above relationship, the first high frequency electric field strength is By applying V1 ≧ 3.7 kV / mm, the nitrogen gas can be excited and put into a plasma state.

  Here, the frequency of the first power source is preferably 200 kHz or less. The electric field waveform may be a continuous wave or a pulse wave. The lower limit is preferably about 1 kHz.

  On the other hand, the frequency of the second power source is preferably 800 kHz or more. The higher the frequency of the second power source, the higher the plasma density, and a dense and high-quality thin film can be obtained. The upper limit is preferably about 200 MHz.

  The application of a high frequency electric field from such two power sources is necessary to start the discharge of a discharge gas having a high discharge start electric field strength by the first high frequency electric field, and the high frequency of the second high frequency electric field. In addition, it is an important point of the present invention to form a dense and high-quality thin film by increasing the plasma density with a high power density.

  Also, by increasing the output density of the first high-frequency electric field, the output density of the second high-frequency electric field can be improved while maintaining the uniformity of discharge. Thereby, a further uniform high-density plasma can be generated, and a further improvement in film formation speed and an improvement in film quality can be achieved.

  In the atmospheric pressure plasma discharge processing apparatus used in the present invention, the first filter facilitates passage of the current of the first high-frequency electric field from the first power source to the first electrode, and grounds the current of the second high-frequency electric field. Thus, it is difficult to pass the current of the second high-frequency electric field from the second power source to the first power source. On the other hand, the second filter makes it easy to pass the current of the second high-frequency electric field from the second power source to the second electrode, grounds the current of the first high-frequency electric field, and the second power from the first power source. The current of the first high-frequency electric field to the power supply is made difficult to pass. In the present invention, any filter having such properties can be used without limitation.

  For example, as the first filter, a capacitor of several tens of pF to several tens of thousands of pF or a coil of about several μH can be used depending on the frequency of the second power source. As the second filter, a coil of 10 μH or more is used according to the frequency of the first power supply, and it can be used as a filter by grounding through these coils or capacitors.

  As described above, the atmospheric pressure plasma discharge treatment apparatus used in the present invention discharges between the counter electrodes, puts the gas introduced between the counter electrodes into a plasma state, and places the gas between the counter electrodes or between the electrodes. By exposing the substrate to be transferred to the plasma state gas, a thin film is formed on the substrate. As another method, the atmospheric pressure plasma discharge treatment apparatus discharges between the counter electrodes similar to the above, excites the gas introduced between the counter electrodes or puts it in a plasma state, and excites or jets the gas outside the counter electrode. There is a jet type apparatus that blows out a plasma gas and exposes a substrate (which may be stationary or transferred) in the vicinity of the counter electrode to form a thin film on the substrate. .

  According to the invention described in claims 1 to 14, the antireflection film is formed on the substrate by exposing the substrate to the excited gas under special discharge conditions. Unlike the case where it is formed on a substrate, there is no problem such as uneven coating and non-uniform thickness of the antireflection film, and the lenticular lens has a high total light transmittance and a high antireflection function. Can do.

  The best mode for carrying out the present invention will be described below with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples.

FIG. 1 is a cross-sectional view schematically showing a screen structure of a display device.
The screen of the display device has a structure composed of a front plate 1, a lenticular lens 2 and a Fresnel lens 3. The front plate 1 is arranged on the front side of the display device (the viewer side of the display device), the lenticular lens 2 is arranged on the rear side of the front plate 1, and the Fresnel is arranged on the rear side of the lenticular lens 2. A lens 3 is arranged.

  As shown in the enlarged view in FIG. 1, the lenticular lens 2 has a configuration in which an antireflection film 6 is formed on both front and rear surfaces of a base material 4. The lenticular lens 2 as a lenticular lens for display according to the present invention is applicable as a lenticular lens for all known display devices, and is applied as a lenticular lens such as a projection display.

  The substrate 4 is not particularly limited as long as it is a lenticular lens capable of forming a thin film on the surface thereof. There is no limitation on the form or material of the base material 4 as long as the base material 4 is exposed to a mixed gas in a plasma state regardless of whether it is in a stationary state or a transported state, and a uniform antireflection film 6 is formed. Various materials such as glass, resin, earthenware, metal, and non-metal can be used.

  In the case where the substrate 4 is made of a resin, the material is a polyolefin (polyethylene) from the viewpoints of optical properties such as transparency, refractive index, dispersion, and various physical properties such as impact resistance, heat resistance, and durability. , Polypropylene, etc.), cyclopolyolefin, polyester (polyethylene terephthalate, polyethylene naphthalate, etc.), polyamide (nylon-6, nylon-6, 6 etc.), polystyrene, polyvinyl chloride, polyimide, polycarbonate, polyvinyl alcohol, ethylene Examples include vinyl alcohol, acrylic, cellulose-based (triacetyl cellulose, diacetyl cellulose, cellophane, etc.), and the like, or copolymers of these organic polymers.

  The antireflection film 6 is a film having a function of preventing incident light directed to the base material 4 from the front side or the rear side of the lenticular lens 2 and is formed of a single layer or has a refractive index. Are formed by laminating a plurality of layers different from each other. “Antireflection film 6” means that a gas G containing a thin film forming gas (see FIG. 2) is supplied to the discharge space and a high-frequency electric field is applied to the discharge space under atmospheric pressure or a pressure in the vicinity thereof. The gas G is excited by the above, and the base material 4 is exposed to the excited gas G to form a film on the base material 4.

  In the lenticular lens 2, the antireflection film 6 is formed on both front and rear surfaces of the base material 4. However, the lenticular lens 2 is formed on at least one surface of the front and back surfaces of the base material 4. A filmed configuration may also be used. In the lenticular lens 2, an antifouling film (not shown) for preventing dirt may be formed on the antireflection film 6 of the substrate 4. As an example of the antifouling film, an antifouling film containing an organometallic compound having an organic group having a fluorine atom can be given.

Next, an atmospheric pressure plasma discharge processing apparatus 10 for forming the antireflection film 6 on the base material 4 of the lenticular lens 2 will be described with reference to FIGS.
As shown in FIG. 2, the atmospheric pressure plasma discharge processing apparatus 10 has a flat and long stage electrode 11. Above the stage electrode 11 as the first electrode, a plasma discharge vessel 12 having an open bottom is disposed. A plurality of rectangular tube electrodes 13 are arranged inside the plasma discharge vessel 12 and above the stage electrode 11.

  As shown in FIG. 2 and FIG. 3, each square tube electrode 13 as the second electrode and the stage electrode 11 are arranged to face each other at a predetermined interval. In the atmospheric pressure plasma discharge processing apparatus 10, the stage electrode 11 and each cylindrical electrode 13 constitute a counter electrode. A drive mechanism (not shown) is connected to the stage electrode 11, and the stage electrode 11 can be reciprocated by the action of the drive mechanism (see arrows in FIGS. 2 and 3).

  As shown in FIG. 4, the stage electrode 11 has a structure in which a flat and long metallic base material 11a is covered with a dielectric 11b. As shown in FIG. 5, the rectangular tube electrode 13 has a structure in which a rectangular tube-shaped metallic base material 13a is covered with a dielectric 13b. Details of the stage electrode 11 and each rectangular tube electrode 13 will be described later.

  The stage electrode 11 and each square tube electrode 13 are both hollow, and in the atmospheric pressure plasma discharge processing apparatus 10, the temperature adjustment is provided in the hollow portion of the stage electrode 11 and each square tube electrode 13. The medium (water, silicon, etc.) is circulated to control the temperature of the stage electrode 11 and each rectangular tube electrode 13.

  As shown in FIG. 1, three gas supply ports 14, 14, 14 for supplying a gas G into the plasma discharge container 12 are provided above the plasma discharge container 12. Above each square tube electrode 13, a mesh 15 is provided for equalizing the flow rate of G supplied into the plasma discharge vessel 12. In the atmospheric pressure plasma discharge processing apparatus 10, a gas G is supplied from each gas supply port 14 into the plasma discharge vessel 12, and further, a discharge space 16 between the stage electrode 11 and each rectangular tube electrode 13 through the mesh 15. A gas G is supplied to the gas.

  A first power source 17 is connected to the stage electrode 11, and the first power source 17 has a first frequency ω 1, electric field strength V 1, and current I 1 in the discharge space 16 between the stage electrode 11 and each rectangular tube electrode 13. The high frequency electric field is applied. On the other hand, a second power source 18 is connected to each square tube electrode 13, and the second power source 18 has a frequency ω 2, an electric field strength V 2, and a discharge space 16 between the stage electrode 11 and each square tube electrode 13. A second high frequency electric field of current I2 is applied.

  A first filter 19 is installed between the stage electrode 11 and the first power source 17. The first filter 19 facilitates the passage of current from the first power source 17 to the stage electrode 11, and the second power source 18 Is designed so that the current from the second power source 18 to the first power source 17 is hardly passed. Further, a second filter 20 is installed between each square tube electrode 13 and the second power source 18, and the second filter 20 passes a current from the second power source 18 to each square tube electrode 13. The current from the first power source 17 is grounded so that the current from the first power source 17 to the second power source 18 is difficult to pass.

  The first power supply 17 preferably applies a higher frequency electric field strength (V1> V2) than the second power supply 18. Further, the first power source 17 and the second power source 18 have the capability of having a frequency ω1 <ω2.

Further, the current between the first power supply 17 and the second power supply 18 is preferably I1 <I2. Current I1 of the first high-frequency electric field is preferably ^{0.3mA / cm 2 ~20mA / cm 2} , more preferably at ^{1.0mA / cm 2 ~20mA / cm 2} . Furthermore, current I2 of the second high-frequency electric field is preferably ^{10mA / cm 2 ~100mA / cm 2} , more preferably ^{20mA / cm 2 ~100mA / cm 2} .

  In the atmospheric pressure plasma discharge processing apparatus 10, each square tube electrode 13 is connected to the stage electrode 11 via the first filter 19, and the second power source 18 is connected to the stage electrode 11 via the second filter 20. May be.

  The stage electrode 11 and each rectangular tube type electrode 13 are subjected to sealing treatment using a sealing material made of an inorganic compound after thermal spraying ceramics as dielectrics 11b and 13b on conductive metallic base materials 11a and 13a, respectively. It is a thing. The ceramic dielectric may be covered by about 1 mm with a single wall. As the ceramic material used for thermal spraying, alumina, silicon nitride, or the like is preferably used. Among these, alumina is particularly preferable because it is easily processed. The layers of the dielectrics 11b and 13b may be lining treated dielectrics provided with an inorganic material by lining.

  Examples of the conductive metallic base materials 11a and 13a include titanium metal or titanium alloy, silver, platinum, stainless steel, aluminum, iron, and other metals, a composite material of iron and ceramics, or a composite material of aluminum and ceramics. Although titanium metal or a titanium alloy is particularly preferable for the reasons described later.

  The distance between the electrodes of the stage electrode 11 and the rectangular tube electrode 13 facing each other is the shortest between the surface of the dielectric and the surface of the conductive metallic base material of the other electrode when a dielectric is provided on one of the electrodes. Say distance. When a dielectric is provided on both electrodes, it means the shortest distance between the dielectric surfaces. The distance between the electrodes is determined in consideration of the thickness of the dielectric provided on the conductive metallic base material, the magnitude of the applied electric field strength, the purpose of using the plasma, etc. From the viewpoint of performing 0.15 mm, 0.1 to 20 mm is preferable, and 0.5 to 2 mm is particularly preferable.

  Details of the conductive metallic base materials 11a and 13a and the dielectrics 11b and 13b will be described later.

  The plasma discharge vessel 12 is preferably a processing vessel made of Pyrex (R) glass or the like, but may be made of metal as long as it can be insulated from the stage electrode 11 or the rectangular tube electrode 13. For example, polyimide resin or the like may be attached to the inner surface of an aluminum or stainless steel frame, and the metal frame may be thermally sprayed to obtain insulation.

As the first power source 17 (high frequency power source) installed in the atmospheric pressure plasma discharge processing apparatus 10,
Applied power symbol Manufacturer Frequency Product name A1 Shinko Electric 3kHz SPG3-4500
A2 Shinko Electric 5kHz SPG5-4500
A3 Kasuga Electric 15kHz AGI-023
A4 Shinko Electric 50kHz SPG50-4500
A5 HEIDEN Research Laboratories 100kHz * PHF-6k
A6 Pearl Industry 200kHz CF-2000-200k
A7 Pearl Industry 400kHz CF-2000-400k
And the like, and any of them can be used.

As the second power source 18 (high frequency power source),
Applied power supply symbol Manufacturer Frequency Product name B1 Pearl Industry 800kHz CF-2000-800k
B2 Pearl Industry 2MHz CF-2000-2M
B3 Pearl Industry 13.56MHz CF-5000-13M
B4 Pearl Industry 27MHz CF-2000-27M
B5 Pearl Industry 150MHz CF-2000-150M
And the like, and any of them can be preferably used.

  Of the above power supplies, * indicates a HEIDEN Laboratory impulse high-frequency power supply (100 kHz in continuous mode). Other than that, it is a high frequency power source that can apply only a continuous sine wave.

  In the present invention, it is preferable that the atmospheric pressure plasma discharge treatment apparatus 10 employs the stage electrode 11 and the rectangular tube electrode 13 that can maintain a uniform and stable discharge state by applying such an electric field.

In the present invention, the electric power applied between the stage electrode 11 and the rectangular tube type electrode 13 supplies electric power (power density) of 1 W / cm ² or more to each rectangular tube type electrode 13 (second high frequency electric field), and discharges. A gas is excited to generate plasma, and energy is applied to the thin film forming gas to form a thin film. The upper limit value of the power supplied to the second electrode 18 is preferably 50 W / cm ² , more preferably 20 W / cm ² . The lower limit is preferably 1.2 W / cm ² . The discharge area (cm ² ) refers to the sum of the areas in the range where discharge occurs in each square tube electrode 13.

Further, by supplying power (output density) of 1 W / cm ² or more to the first electrode 17 (first high-frequency electric field), the output density is improved while maintaining the uniformity of the second high-frequency electric field. It can be made. Thereby, a further uniform high-density plasma can be generated, and a further improvement in film forming speed and an improvement in film quality can be achieved. Preferably it is 5 W / cm ² or more. The upper limit value of the power supplied to the first electrode 17 is preferably 50 W / cm ² .

  Here, the waveform of the high-frequency electric field is not particularly limited. There are a continuous sine wave continuous oscillation mode called a continuous mode and an intermittent oscillation mode called ON / OFF intermittently called a pulse mode. Either of them may be adopted, but at least the rectangular tube electrode 13 side ( The second high-frequency electric field is preferably a continuous sine wave because a denser and better quality film can be obtained.

  The stage electrode 11 and each rectangular tube electrode 13 used in such a method of forming a thin film by atmospheric pressure plasma must be able to withstand severe conditions in terms of structure and performance. As such a stage electrode 11 and each rectangular tube type electrode 13, it is preferable that the metal base materials 11a and 13a are covered with dielectrics 11b and 13b.

In the stage electrode 11 and each square tube type electrode 13 used in the present invention, it is preferable that the characteristics match between the various metallic base materials 11a, 13a and the dielectrics 11b, 13b. This is a combination in which the difference in coefficient of linear thermal expansion between the metallic base materials 11a and 13a and the dielectrics 11b and 13b is 10 × 10 ⁻⁶ / ° C. or less. It is preferably 8 × 10 ⁻⁶ / ° C. or less, more preferably 5 × 10 ⁻⁶ / ° C. or less, and further preferably 2 × 10 ⁻⁶ / ° C. or less. The linear thermal expansion coefficient is a well-known physical property value of a material.

As a combination of the conductive metallic base materials 11a and 13a and the dielectrics 11b and 13b within which the difference in linear thermal expansion coefficient is in this range,
1: Metal base materials 11a and 13a are pure titanium or titanium alloy, and dielectrics 11b and 13b are ceramic sprayed coatings 2: Metal base materials 11a and 13a are pure titanium or titanium alloy, and dielectrics 11b and 13b are glass. Lining 3: Metal base materials 11a and 13a are stainless steel, dielectrics 11b and 13b are ceramic sprayed coatings 4: Metal base materials 11a and 13a are stainless steel, and dielectrics 11b and 13b are glass linings 5: Metal Base materials 11a, 13a are composite materials of ceramics and iron, dielectrics 11b, 13b are ceramic sprayed coatings 6: Metal base materials 11a, 13a are composite materials of ceramics and iron, and dielectrics 11b, 13b are glass linings 7. : Metal base materials 11a and 13a are composite materials of ceramics and aluminum. Body 11b, 13b ceramics sprayed coating 8: metal base material 11a, 13a is a composite material of ceramics and aluminum, a dielectric 11b, 13b there is a glass-lined, and the like. From the viewpoint of the difference in coefficient of linear thermal expansion, the above item 1 or 2 and 5-8
Term is preferable, and 1 term is particularly preferable.

  In the present invention, the metal base materials 11a and 13a are particularly useful from the above characteristics. By using the metal base materials 11a and 13a as titanium or a titanium alloy, and by setting the dielectrics 11b and 13b as described above, deterioration of the stage electrode 11 and each rectangular tube electrode 13 in use, particularly cracking and peeling, There is no dropout and can withstand long-term use under harsh conditions.

  The metal base materials 11a and 13a of the stage electrode 11 and each rectangular tube electrode 13 useful for the present invention are titanium alloys or titanium metals containing 70 mass% or more of titanium. In the present invention, if the titanium content in the titanium alloy or titanium metal is 70% by mass or more, it can be used without any problem, but preferably contains 80% by mass or more of titanium. As the titanium alloy or titanium metal useful in the present invention, those generally used as industrial pure titanium, corrosion resistant titanium, high strength titanium and the like can be used. Examples of pure titanium for industrial use include TIA, TIB, TIC, TID, etc., all of which contain very little iron atom, carbon atom, nitrogen atom, oxygen atom, hydrogen atom, etc. As content, it has 99 mass% or more. As the corrosion-resistant titanium alloy, T15PB can be preferably used, and it contains lead in addition to the above-mentioned atoms, and the titanium content is 98% by mass or more. Further, as the titanium alloy, T64, T325, T525, TA3, etc. containing aluminum and vanadium or tin in addition to the above atoms except lead can be preferably used. As a quantity, it contains 85 mass% or more. These titanium alloys or titanium metals have a thermal expansion coefficient smaller than that of stainless steel, for example, AISI 316, and are described below as dielectric materials applied on the titanium alloys or titanium metals as the metallic base materials 11a and 13a. The combination with 11b and 13b is good and it can endure use at high temperature for a long time.

  On the other hand, as the required characteristics of the dielectrics 11b and 13b, specifically, an inorganic compound having a relative dielectric constant of 6 to 45 is preferable, and as the dielectrics 11b and 13b, alumina, There are ceramics such as silicon nitride, or glass lining materials such as silicate glass and borate glass. In this, what sprayed the ceramics mentioned later and the thing provided by glass lining are preferable. In particular, dielectrics 11b and 13b provided by spraying alumina are preferable.

  Alternatively, as one of the specifications that can withstand high power as described above, the porosity of the dielectrics 11b and 13b is 10% by volume or less, preferably 8% by volume or less, and preferably exceeds 0% by volume to 5%. % By volume or less. The porosity of the dielectrics 11b and 13b can be measured by a BET adsorption method or a mercury porosimeter. In the examples described later, the porosity is measured by using pieces of dielectrics 11b and 13b covered with metallic base materials 11a and 13a by a mercury porosimeter manufactured by Shimadzu Corporation. High durability is achieved by the dielectrics 11b and 13b having a low porosity. Examples of the dielectrics 11b and 13b having such voids and low porosity include high-density, high-adhesion ceramic sprayed coatings by the atmospheric plasma spraying method described later. In order to further reduce the porosity, it is preferable to perform sealing treatment.

  The above-mentioned atmospheric plasma spraying method is a technique in which fine powder such as ceramics, wire or the like is put into a plasma heat source and sprayed onto the metal base materials 11a and 13a to be coated as fine particles in a molten or semi-molten state to form a film. It is. A plasma heat source is a high-temperature plasma gas in which a molecular gas is heated to a high temperature, dissociated into atoms, and further given energy to release electrons. This plasma gas injection speed is high, and compared with conventional arc spraying and flame spraying, the sprayed material collides with the metallic base materials 11a and 13a at a high speed, so that the adhesion strength is high and a high-density coating can be obtained. I can do it. For details, a thermal spraying method for forming a heat shielding film on a high-temperature exposed member described in JP-A No. 2000-301655 can be referred to. By this method, the porosity of the dielectrics 11b and 13b (ceramic sprayed film) to be coated can be obtained.

  Another preferred specification that can withstand high power is that the dielectrics 11b and 13b have a thickness of 0.5 to 2 mm. The film thickness variation is desirably 5% or less, preferably 3% or less, and more preferably 1% or less.

In order to further reduce the porosity of the dielectrics 11b and 13b, it is preferable to further perform a sealing treatment with an inorganic compound on the thermal spray film such as ceramics as described above. As the inorganic compound, a metal oxide is preferable, and among these, a compound containing silicon oxide (SiO _x ) as a main component is particularly preferable.

  The inorganic compound for sealing treatment is preferably formed by curing by a sol-gel reaction. In the case where the inorganic compound for sealing treatment contains a metal oxide as a main component, a metal alkoxide or the like is applied as a sealing liquid on the ceramic sprayed film and cured by a sol-gel reaction. When the inorganic compound is mainly composed of silica, it is preferable to use alkoxysilane as the sealing liquid.

  Here, it is preferable to use energy treatment for promoting the sol-gel reaction. Examples of the energy treatment include thermal curing (preferably 200 ° C. or less) and ultraviolet irradiation. Furthermore, as a method of sealing treatment, when the sealing liquid is diluted and coating and curing are repeated several times in succession, the mineralization is further improved, and the dense stage electrode 11 and the rectangular tube electrode 13 without deterioration can be formed. .

When sealing the ceramic sprayed film using the metal alkoxide or the like of the stage electrode 11 and the rectangular tube type electrode 13 coated with the dielectrics 11b and 13b according to the present invention as a sealing liquid, and performing a sealing process that cures by a sol-gel reaction The content of the metal oxide after curing is preferably 60 mol% or more. When alkoxysilane is used as the metal alkoxide of the sealing liquid, the content of SiO _x (x is 2 or less) after curing is preferably 60 mol% or more. The cured SiO _x content is measured by analyzing the tomographic layers of the dielectrics 11b and 13b by XPS (X-ray photoelectron spectroscopy).

  In the stage electrode 11 according to the thin film forming method of the present invention, the maximum height (Rmax) of the surface roughness defined by JIS B 0601 on the side in contact with the base material 4 of the stage electrode 11 is 10 μm or less. The adjustment is preferable from the viewpoint of obtaining the effects described in the present invention, but more preferably, the maximum value of the surface roughness is 8 μm or less, and particularly preferably 7 μm or less. As described above, by polishing the surface of the dielectric 11b of the stage electrode 11, the thickness of the dielectric 11b and the gap between the stage electrode 11 and the rectangular tube electrode 13 can be kept constant, and the discharge state is stabilized. In addition, distortion and cracking due to thermal shrinkage difference and residual stress can be eliminated, and durability can be greatly improved with high accuracy. The polishing finish on the surface of the dielectric 11b is preferably performed at least on the dielectric 11b on the side in contact with the substrate 4. Furthermore, the centerline average surface roughness (Ra) defined by JIS B 0601 is preferably 0.5 μm or less, more preferably 0.1 μm or less.

  In the stage electrode 11 and each rectangular tube electrode 13 covered with the dielectrics 11b and 13b used in the present invention, another preferred specification that can withstand high power is that the heat-resistant temperature is 100 ° C. or higher. More preferably, it is 120 degreeC or more, Most preferably, it is 150 degreeC or more. The upper limit is 500 ° C. Note that the heat-resistant temperature refers to the highest temperature that can withstand normal discharge without causing dielectric breakdown at the voltage used in the atmospheric pressure plasma treatment. Such heat-resistant temperature can be applied by applying the dielectrics 11b and 13b provided by the above-mentioned ceramic spraying and layered glass linings with different amounts of bubbles mixed, or by the metallic base materials 11a and 13a and the dielectrics 11b and 13b. This can be achieved by appropriately combining means for appropriately selecting materials within the range of differences in linear thermal expansion coefficients.

Next, “gas G” supplied to the discharge space 16 will be described.
The gas G supplied to the discharge space 16 contains at least a discharge gas and a thin film forming gas. The discharge gas and the thin film forming gas may be mixed and supplied, or may be supplied separately.

  “Discharge gas” is a gas capable of causing glow discharge capable of forming a thin film. Examples of the discharge gas include nitrogen, rare gas, air, hydrogen gas, oxygen, and the like. These may be used alone as a discharge gas or may be mixed. In the present invention, nitrogen is preferred as the discharge gas. It is preferable that 50-100 volume% of discharge gas is nitrogen gas. At this time, as the discharge gas other than nitrogen, it is preferable to contain a rare gas of less than 50% by volume. Moreover, it is preferable to contain 90-99.9 volume% of quantity of discharge gas with respect to the total gas quantity supplied to discharge space.

  The “thin film forming gas” is a raw material that is activated by itself and becomes chemically activated and deposited on the substrate 4 to form a thin film.

  Next, the gas G supplied to the discharge space 16 in order to form the thin film used for this invention is demonstrated. The discharge gas and the thin film forming gas are basically used, but an additive gas may be further added. The total amount of gas supplied to the discharge space 16 preferably contains 90 to 99.9% by volume of discharge gas.

  Examples of the thin film forming gas used in the present invention include organometallic compounds, halogen metal compounds, and metal hydrogen compounds.

The organometallic compounds useful in the present invention are preferably those represented by the following general formula (I).
R ¹ _x MR ² _y R ³ _z (I)

In formula (I), M is a metal, R ¹ is an alkyl group, R ² is an alkoxy group, R ³ is a β-diketone complex group, a β-ketocarboxylic acid ester complex group, a β-ketocarboxylic acid complex group, and a ketooxy group (ketooxy group). Complex group), and when the valence of the metal M is m, x + y + z = m, x = 0 to m, or x = 0 to m−1, y = 0 to m, z = 0 to m, each of which is 0 or a positive integer. Examples of the alkyl group for R ¹ include a methyl group, an ethyl group, a propyl group, and a butyl group. Examples of the alkoxy group for R ² include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, and a 3,3,3-trifluoropropoxy group. Further, a hydrogen atom in the alkyl group may be substituted with a fluorine atom. Examples of the group selected from the β-diketone complex group, β-ketocarboxylic acid ester complex group, β-ketocarboxylic acid complex group and ketooxy group (ketooxy complex group) of R ³ include, for example, 2,4 -Pentanedione (also called acetylacetone or acetoacetone), 1,1,1,5,5,5-hexamethyl-2,4-pentanedione, 2,2,6,6-tetramethyl-3,5-heptanedione 1,1,1-trifluoro-2,4-pentanedione, etc., and β-ketocarboxylic acid ester complex groups include, for example, acetoacetic acid methyl ester, acetoacetic acid ethyl ester, acetoacetic acid propyl ester, trimethyl Examples thereof include ethyl acetoacetate and methyl trifluoroacetoacetate. As β-ketocarboxylic acid, Eg to acetoacetate, it can be mentioned trimethyl acetoacetate, and as Ketookishi, for example, acetoxy group (or an acetoxy group), a propionyloxy group, Buchirirokishi group, acryloyloxy group, methacryloyloxy group and the like. The number of carbon atoms of these groups is preferably 18 or less, including the above-mentioned organometallic compounds. Further, as illustrated, it may be linear or branched, or a hydrogen atom substituted with a fluorine atom.

In the present invention, an organometallic compound having a low risk of explosion is preferred from the viewpoint of handling, and an organometallic compound having at least one oxygen in the molecule is preferred. As such, an organometallic compound containing at least one alkoxy group of R ² , a β-diketone complex group, a β-ketocarboxylic acid ester complex group, a β-ketocarboxylic acid complex group of R ³ and a ketooxy group (ketooxy group) A metal compound having at least one group selected from (complex group) is preferred.

A specific organometallic compound will be described later.
In the present invention, the gas G supplied to the discharge space 16 may be mixed with an additive gas for promoting a reaction for forming a thin film, in addition to the discharge gas and the thin film forming gas. Examples of the additive gas include oxygen, ozone, hydrogen peroxide, carbon dioxide, carbon monoxide, hydrogen, ammonia and the like, but oxygen, carbon monoxide and hydrogen are preferable, and components selected from these are mixed. It is preferable to do so. The content is preferably 0.01 to 5% by volume based on the total amount of gas, whereby the reaction is promoted and a dense and high-quality thin film can be formed.

  The thickness of the formed oxide or composite compound thin film is preferably in the range of 0.1 to 1000 nm.

  In the present invention, Li, Be, B, Na, Mg, Al, Si, K, Ca, Sc, Ti, V, Cr are used as the metal of the organometallic compound, metal halide, and metal hydride compound used for the thin film forming gas. , Mn, Fe, Co, Ni, Cu, Zn, Ga, Ge, Rb, Sr, Y, Zr, Nb, Mo, Cd, In, Ir, Sn, Sb, Cs, Ba, La, Hf, Ta, W , Tl, Pb, Bi, Ce, Pr, Nd, Pm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and the like.

  In the thin film forming method of the present invention, various high-functional thin films can be obtained by using a metal compound such as an organic metal compound, a halogen metal compound, or a metal hydrogen compound together with a discharge gas. Although the example of the thin film of this invention is shown below, this invention is not limited to this.

Electrode film: Au, Al, Ag, Ti, Ti, Pt, Mo, Mo-Si
Dielectric protective film: SiO ₂ , SiO, Si ₃ N ₄ , Al ₂ O ₃ , Al ₂ O ₃ , Y ₂ O ₃
Transparent conductive film: In ₂ O ₃ , SnO ₂
Electrochromic film: WO ₃ , IrO ₂ , MoO ₃ , V ₂ O ₅
Fluorescent film: ZnS, ZnS + ZnSe, ZnS + CdS
Magnetic recording film: Fe—Ni, Fe—Si—Al, γ-Fe ₂ O ₃ , Co, Fe ₃ O ₄ , Cr, SiO ₂ , AlO ₃
Super conductive film: Nb, Nb-Ge, NbN
Solar cell film: a-Si, Si
Reflective film: Ag, Al, Au, Cu
Selective absorption membrane: ZrC-Zr
Selective permeable membrane: In ₂ O ₃ , SnO ₂
Antireflection film: SiO ₂ , TiO ₂ , SnO ₂
Shadow mask: Cr
Abrasion resistant film: Cr, Ta, Pt, TiC, TiN
Corrosion resistant film: Al, Zn, Cd, Ta, Ti, Cr
Heat-resistant film: W, Ta, Ti
Lubricating film: MoS ₂
Decorative film: Cr, Al, Ag, Au, TiC, Cu

  The nitridation degree of the nitride, the oxidation degree of the oxide, the sulfide degree of the sulfide, and the carbonization degree of the carbide are merely examples, and the composition ratio with the metal may be changed as appropriate. In addition to the metal compound, the thin film may contain impurities such as a carbon compound, a nitrogen compound, and a hydrogen compound.

  In the present invention, particularly preferred metals of the metal compound are Si (silicon), Ti (titanium), Sn (tin), Zn (zinc), In (indium), and Al (aluminum) among these metals. Of the metal compounds that bind to, the organometallic compounds represented by the general formula (I) are preferred. Examples of the organometallic compound will be described later.

Next, a method for manufacturing the lenticular lens 2 will be described.
In the case of forming the antireflection film 6 on the base material 4, the antireflection film 6 is formed on the base material 4 using the atmospheric pressure plasma discharge processing apparatus 10. The method of forming the antireflection film 6 on the substrate 4 will be described in detail. First, the substrate 4 is placed and fixed on the stage electrode 11, and the stage electrode 11 is reciprocated in the left-right direction in FIG. In synchronism with this, gas G is supplied from each gas supply port 14 to the discharge space 16 between the stage electrode 11 and each rectangular tube electrode 13 under atmospheric pressure or a pressure in the vicinity thereof, and the first power supply 17 A first high frequency electric field having a frequency ω1, an electric field strength V1, and a current I1 is applied to the discharge space 16 from a second power source 18 and a second high frequency electric field having a frequency ω2, an electric field strength V2, and a current I2 is applied from the second power source 18 to the discharge space 16.

At this time, the first high-frequency electric field and the second high-frequency electric field overlap each other. However, regarding these high-frequency electric fields, the frequency ω2 of the second high-frequency electric field is higher than the frequency ω1 of the first high-frequency electric field. The relationship between the electric field strength V1, the second high-frequency electric field strength V2, and the discharge start electric field strength IV satisfies V1 ≧ IV> V2 or V1> IV ≧ V2, and the second high-frequency electric field A high frequency electric field is applied to the discharge space 16 from the first power source 17 and the second power source 18 so that the output density is 1 W / cm ² or more.

  In this state, the gas G supplied to the discharge space 16 is excited, the substrate 4 on the stage electrode 11 is exposed to the excited gas G, and a thin film is formed and formed on the substrate 4.

  Here, the atmospheric pressure plasma discharge treatment apparatus 10 is configured to form a thin film on the substrate 4 by performing the above-described operation, and to form a single-layer antireflection film 6 having a desired refractive index, Alternatively, the antireflection film 6 in which a plurality of layers having different refractive indexes are laminated is formed by appropriately changing the material of the thin film forming gas.

  The thin film forming gas for forming the thin film is not limited as long as it is a compound capable of obtaining an appropriate refractive index, but a titanium compound can be preferably used as the thin film forming gas for forming the high refractive index layer, As a thin film forming gas for forming the low refractive index layer, a silicon compound, a fluorine compound, or a mixture of a silicon compound and a fluorine compound can be preferably used. In order to adjust the refractive index of these compounds, a mixture of two or more thin-film forming gases for forming any layer may be used.

  Examples of the titanium compound used in the thin film forming gas for forming the high refractive index layer include an organic titanium compound, a titanium hydrogen compound, and a titanium halide. Examples of the organic titanium compound include triethoxy titanium, trimethoxy titanium, trimethyl titanium, and the like. Isopropoxy titanium, tributoxy titanium, tetraethoxy titanium, tetraisopropoxy titanium, methyl dimethoxy titanium, ethyl triethoxy titanium, methyl triisopropoxy titanium, triethyl titanium, triisopropyl titanium, tributyl titanium, tetraethyl titanium, tetraisopropyl titanium, tetra Butyl titanium, tetradimethylamino titanium, dimethyl titanium di (2,4-pentanedionate), ethyl titanium tri (2,4-pentanedionate), titanium tris (2,4-pentanedionate) ), Titanium tris (acetomethyl acetate), triacetoxy titanium, dipropoxypropionyloxy titanium, etc., dibutylyloxy titanium, titanium hydrogen compound as monotitanium hydrogen compound, dititanium hydrogen compound, etc., titanium halide as trichlorotitanium And tetrachlorotitanium. Two or more of these thin film forming gases can be mixed and used at the same time.

  Examples of the silicon compound used for the thin film forming gas for forming the low refractive index layer include organic silicon compounds, silicon hydrogen compounds, and silicon halide compounds. Examples of the organic silicon compounds include tetraethylsilane and tetramethyl. Silane, tetraisopropylsilane, tetrabutylsilane, tetraethoxysilane, tetraisopropoxysilane, tetrabutoxysilane, dimethyldimethoxysilane, diethyldiethoxysilane, diethylsilanedi (2,4-pentanedionate), methyltrimethoxysilane, Examples of silicon hydrogen compounds such as methyltriethoxysilane and ethyltriethoxysilane include tetrahydrogen silane and hexahydrogen disilane. Examples of halogenated silicon compounds include tetrachlorosilane, methyltrichlorosilane, and diethyldichlorosilane. It can be mentioned emissions, and the like. Moreover, the said fluorine compound can be used. Two or more of these thin film forming gases can be mixed and used at the same time. In addition, two or more of these tin compounds, titanium compounds, and silicon compounds may be appropriately mixed and used for fine adjustment of the refractive index.

  The organotitanium compound or organosilicon compound is preferably a metal hydride compound or an alkoxy metal from the viewpoint of handling, and is preferably an alkoxy metal because it is not corrosive, does not generate harmful gases, and has little contamination in the process. It is done. Further, in order to introduce the above-mentioned organotin compound, organotitanium compound or organosilicon compound into the discharge space 16 (between the stage electrode 11 and each square tube electrode 13), both are at normal temperature and normal pressure, gas, liquid Any solid state may be used. In the case of gas, it can be introduced into the discharge space 16 as it is, but in the case of liquid or solid, it is used after being vaporized by means such as heating, decompression or ultrasonic irradiation. When an organotin compound, an organotitanium compound or an organosilicon compound is vaporized by heating, a metal alkoxide such as tetraethoxy metal or tetraisopropoxy metal that is liquid at room temperature and has a boiling point of 200 ° C. or less is suitable for forming a thin film. Used for. The alkoxy metal may be used after being diluted with a solvent. In this case, the alkoxy metal may be vaporized into a rare gas by a vaporizer or the like and used as a mixed gas. As the solvent, organic solvents such as methanol, ethanol, isopropanol, butanol, n-hexane, and mixed solvents thereof can be used.

  Regarding the thin film forming gas, from the viewpoint of forming a uniform thin film on the substrate 4 by discharge plasma treatment, the content in the total gas G is preferably 0.01 to 10% by volume, more preferably, 0.01 to 1% by volume.

  When the anti-reflection film 6 is formed on one surface of the base material 4 using the atmospheric pressure plasma discharge treatment apparatus 10, the same operation as described above is repeated, and the anti-reflection film 6 is formed on the other surface of the base material 4. To form the lenticular lens 2. However, the manufacturing method of the antireflection film 6 using the atmospheric pressure plasma discharge processing apparatus 10 may be applied only to one side of the base material 4 to form the antireflection film 6 only on one side of the base material 4.

  In the present embodiment described above, the atmospheric pressure plasma discharge processing apparatus 10 exposes the base material 4 to the excited gas G under the special discharge conditions to form the antireflection film 6 on the base material 4. Therefore, unlike the case where the antireflection film 6 is formed on the substrate 4 by the coating technique, the lenticular lens 2 does not have a problem such as uneven coating and the film thickness of the antireflection film 6 is not uniform. The rate is high and an advanced antireflection function can be provided.

  In the above embodiment, the antireflection film 6 is formed on the substrate 4 by the atmospheric pressure plasma discharge processing apparatus 10 shown in FIG. 2, but instead of the atmospheric pressure plasma discharge processing apparatus 10 shown in FIG. The antireflection film 6 may be formed on the substrate 4 by the jet-type atmospheric pressure plasma discharge treatment apparatus 30 shown.

  Here, the jet type atmospheric pressure plasma discharge treatment apparatus 30 will be described with reference to FIG. However, in the following description of the atmospheric pressure plasma discharge processing apparatus 30, the components already described in the description of the atmospheric pressure plasma discharge processing apparatus 10 are denoted by the same reference numerals as those of the atmospheric pressure plasma discharge processing apparatus 10 and their configurations. Detailed descriptions of elements are omitted.

  As shown in FIG. 6, in the atmospheric pressure plasma discharge treatment apparatus 30, the two rectangular tube-shaped electrodes 13 are arranged to face each other with a predetermined interval. A first power source 17 is connected to one square tube electrode 13 (first electrode), and a second power source 18 is connected to the other square tube electrode 13 (second electrode).

  A first filter 19 is installed between the one square tube electrode 13 and the first power supply 17. The first filter 19 facilitates the passage of current from the first power source 17 to the one of the rectangular tube-shaped electrodes 13, grounds the current from the second power source 18, and transfers the current from the second power source 18 to the first power source 17. It is designed to make it difficult for current to pass through.

  A second filter 20 is installed between the other rectangular tube electrode 13 and the second power source 18. The second filter 20 facilitates the passage of a current from the second power source 18 to the other rectangular tube electrode 13, grounds the current from the first power source 17, and the first power source 17 to the second power source 18 It is designed to make it difficult to pass current.

  In the atmospheric pressure plasma discharge processing apparatus 30, if the high-frequency voltage probes 31, 32 and the oscilloscopes 33, 34 are installed as shown in FIG. 6, the high-frequency electric field strengths V1, V2 (applied electric field strength) and the discharge start electric field strength Can be measured.

  In the case of forming a thin film on the substrate 4 by the atmospheric pressure plasma discharge treatment apparatus 30 having such a configuration, the gas G is supplied from the gas supply means (not shown) into the discharge space 35 between the square tube electrodes 13. Introducing, generating a discharge by applying a high-frequency electric field from each square tube electrode 13, while blowing the gas G to the lower side (the lower side of the paper surface) of each square tube electrode 13 in a plasma state, A processing space formed by the lower surface of each square tube electrode 13 and the base material 4 is filled with a plasma state gas G °, and the base material 4 is exposed to the plasma state gas G ° in the vicinity of the processing position 36 to form a thin film on the base material 4. To form. Also in this case, as described above, a single-layer antireflection film 6 having a desired refractive index is formed, or a plurality of layers having different refractive indexes are laminated by appropriately changing the material of the thin film forming gas. The antireflection film 6 thus formed is formed.

  During the formation of the thin film, a medium passes from the electrode temperature adjusting means (not shown) through the pipe to heat or cool each square tube electrode 13. Depending on the temperature of the substrate 4 during the plasma discharge treatment, the properties, composition, etc. of the thin film to be obtained may change, and it is desirable to appropriately control this. As the temperature control medium, an insulating material such as distilled water or oil is preferably used. During the plasma discharge treatment, it is desired to uniformly adjust the temperature inside each square tube electrode 13 so that temperature unevenness of the base material 4 in the width direction or the longitudinal direction does not occur as much as possible.

  A plurality of jet-type atmospheric pressure plasma discharge treatment apparatuses 30 are arranged in series and different thin film forming gases are jet-jetted from the respective atmospheric pressure plasma discharge treatment apparatuses 30 to alternately alternate the high refractive index layer and the low refractive index layer. Four layers of the antireflection film 6 may be formed.

[Production of electrodes]
A stage electrode and a rectangular tube electrode were prepared as follows. A hollow jacketed titanium alloy T64 stage electrode and square tube electrode were prepared as follows. High-density, high-adhesion alumina sprayed coatings were coated on the mutually facing surfaces of the stage electrode and the rectangular tube type electrode by the atmospheric plasma method. Thereafter, a solution obtained by diluting tetramethoxysilane with ethyl acetate was applied and dried, and then cured by ultraviolet irradiation to perform sealing treatment. The surface of the dielectric thus coated was polished and smoothed so that the Rmax was 5 μm. The final dielectric porosity was 5% by volume. At this time, the SiO _x content of the dielectric layer was 75 mol%. The final dielectric film thickness was 1 mm (thickness variation within ± 1%), and the relative dielectric constant of the dielectric was 10. Further, the difference in coefficient of linear thermal expansion between the conductive metallic base material and the dielectric was 1.6 × 10 ⁻⁶ / ° C., and the heat resistant temperature was 250 ° C.

[Atmospheric pressure plasma discharge treatment equipment]
Using the atmospheric pressure plasma discharge treatment apparatus shown in FIG. 2, the stage electrode and the rectangular tube electrode produced above are spaced apart so that the distance between the rectangular tube electrode and the surface of the substrate is 1 mm. The first electric field and the second electric field shown in Table 1 were installed to face each other in parallel. The power source A5 was used at a continuous mode of 100 kHz (the same applies to the following examples). Sample No. No. 16 used a DC pulse power source for the first electric field, and the ON / OFF repetition frequency was 10 kHz. Both electrodes were adjusted and kept at 65 ° C. In either case, a filter was installed so that the current from the stage electrode and the rectangular tube electrode did not flow backward.

[Preparation of titanium oxide thin film]
Using a mixed gas of the following composition on a commercially available PMMA (polymethylmethacrylate) plate (base material), the electric field shown in Table 1 is applied between the stage electrode and each rectangular tube type electrode, and discharge is performed to form a thin film. Samples 1 to 16 were prepared. In addition, the electric discharge start electric field strength in this system was 4.5 kV / mm.

<Mixed gas composition>
Discharge gas: Nitrogen 97.9% by volume
Thin film forming gas: tetraisopropoxy titanium 0.1% by volume
Addition gas: Hydrogen 2.0% by volume

[Evaluation]
<Discharge state>
The discharge status was divided into the following ranks between the counter electrodes (between the stage electrode and the rectangular tube type electrode).
○: Stable discharge is occurring Δ: Discharge is occurring but somewhat unstable ×: No discharge occurs

<Refractive index>
The reflection spectra were measured for each sample 1 to 16 using a spectrophotometer U-4000 type (manufactured by Hitachi, Ltd.) under the condition of regular reflection at 5 degrees. In the measurement, the surface of the base material on which the thin film is not formed by the atmospheric pressure plasma discharge treatment is roughened, and then light absorption treatment is performed using a black spray to prevent reflection of light on the back surface of the base material. A reflection spectrum having a wavelength of ˜700 nm was measured, an optical film thickness was calculated from a λ / 4 value of the spectrum, and a refractive index was calculated based on the optical film thickness. The low refractive index means that the layer structure lacks the density and there are a large number of holes, and the phenomenon that air enters into the holes during measurement and the particles generated in the discharge space may be taken into the film. There is a bad film.

  Sample No. above. For 1 to 16, the discharge state was observed and the refractive index was measured, and the results are shown in Table 1.

(result)
Relationship between the frequency (ω1, ω2) of the first and second high frequency electric fields applied from the stage electrode and each rectangular tube type electrode, the strength (V1, V2) of the first and second high frequency electric fields and the discharge of the discharge gas The relationship between the strength of the starting electric field (IV) and the output density of the second high-frequency electric field is the sample No. About 1-10, the discharge condition was also favorable and the precise | minute thin film (it can judge by the magnitude | size of a refractive index) was formed. On the other hand, in the samples 11 to 16 of the high-frequency electric field other than the relationship of the present invention, the ability to form a thin film is insufficient even if the discharge is good, and a dense thin film with many holes cannot be obtained (refractive index). Is small), or discharge did not occur and a thin film could not be formed.

  Samples 17 to 23 were produced in the same manner as in Example 1 except that the first electric field and the second electric field shown in Table 2 were changed and the first filter and the second filter shown in Table 2 were installed.

  Sample No. The above evaluation was performed for 17 to 23, and the results are shown in Table 2.

(result)
Samples 17 to 20 in which a filter was installed as shown in Table 2 and a thin film was formed using an atmospheric pressure plasma discharge treatment apparatus were normally discharged, and the thin film was also formed normally. On the other hand, in sample 21, since the combination of the filters was not appropriate for the frequencies of the first electric field and the second electric field, no discharge occurred and a thin film could not be formed. Samples 22 and 23 are normal atmospheric discharge plasma thin film forming apparatuses, in which the counter electrode is an application electrode and a ground electrode (no filter is used). In sample 22, a higher frequency is applied to the application electrode than is normally used. Although it was applied from the power source, it was not discharged and a thin film could not be formed. In Sample 23, the applied power source was applied using a lower frequency one, but although it was discharged, a good thin film could not be formed. It was.

  A PMMA lenticular lens was used as the substrate, and an atmospheric pressure plasma discharge treatment apparatus similar to that shown in FIG. 2 was used as the apparatus. A base material was placed on the stage electrode to form an antireflection film. Specifically, the stage electrode is reciprocated to form a high refractive index layer on the base material, and then a low refractive index layer is formed on the high refractive index layer, followed by low refractive index. A high refractive index layer is laminated on the refractive index layer, and then a low refractive index layer is laminated on the high refractive index layer, and the base material / high refractive index layer / low refractive index layer / A high-refractive index layer / low-refractive index layer lenticular lens with an antireflection film (Sample Nos. 24-27) was produced.

[Production of lenticular lens with antireflection film]
During plasma discharge, the stage electrode and each square tube electrode were adjusted and kept at 65 ° C. to form an antireflection film as follows. The first electric field and the second electric field in the film formation of each layer were the same as those shown in Table 3. The pressure is 103 kPa, the following mixed gas is introduced into each discharge space and plasma discharge vessel, and a high refractive index layer, a low refractive index layer, a high refractive index layer, and a low refractive index layer are formed on the PMMA lenticular lens. A plasma discharge thin film was formed in this order to prepare a four-layer laminated lenticular lens with an antireflection film, which was designated as samples 24-27.

<< High refractive index layer mixed gas composition >>
Discharge gas: Nitrogen 99.4% by volume
Thin film forming gas: tetraisopropoxy titanium 0.1% by volume
(Vaporized by mixing with argon gas using a vaporizer manufactured by Lintec)
Additive gas: 0.5% by volume of oxygen gas
<< High refractive index layer conditions >>
Output density: Stage electrode side 1 W / cm ²
: Square tube type electrode side 5W / cm ²

<< Low refractive index layer mixed gas composition >>
Discharge gas: Nitrogen 98.9% by volume
Thin film forming gas: Tetraethoxysilane 0.1% by volume
(Vaporized by mixing with argon gas using a vaporizer manufactured by Lintec)
Additive gas: 1% by volume of oxygen gas
<< Low refractive index layer conditions >>
Output density: Stage electrode side 1 W / cm ²
: Square tube electrode side 3W / cm ²

(Preparation of antireflection film by vacuum deposition)
As the vacuum deposition apparatus, a continuous vacuum deposition apparatus provided with a preheating chamber, a first deposition chamber, and a second deposition chamber independently was used. The PMMA lenticular lens is mounted on a support, put into a preheating chamber, heated in a vacuum atmosphere for a predetermined time, and then brought into a first vapor deposition chamber that is already in a vacuum state without being exposed to the outside air by a transfer device provided inside. Then, an antireflection film was formed in the first vapor deposition chamber as follows.

First, a PMMA lenticular lens heated to a temperature suitable for this deposition is subjected to a vacuum deposition method (vacuum degree of 2 × 10 ⁻⁵ Torr) by an ion beam assist method in which an oxygen ion beam is irradiated to the PMMA lenticular lens. A lenticular with a four-layer antireflection film consisting of a layer made of titanium, a layer made of silicon dioxide by a vacuum deposition method, a layer made of titanium dioxide by an ion beam assist method, and a layer made of silicon dioxide by a vacuum deposition method A lens was manufactured and used as Sample 28.

(Preparation of antireflection film by coating)
A coating agent was applied onto the lenticular lens as described below to produce a lenticular lens with an antireflection film. A thin film was formed by dipping into a transparent fluororesin solution with a low refractive index [Cytop manufactured by Asahi Glass Co., Ltd.] and pulling it up at a constant speed. In this way, a lenticular lens with an antireflection film was prepared and used as Sample 29.

For samples 24-29, the discharge state was evaluated in the same manner as in Example 1,
And the following evaluation was performed and the result was shown in Table 3.

[Evaluation]
(Total light transmittance)
The total transmitted light amount with respect to the incident light amount of visible light was measured according to ASTM D-1003.

(Appearance of lenticular lens with antireflection film)
Light absorption treatment is performed using black spray to prevent reflection of light on the back surface of the lenticular lens with antireflection film, and the illuminance of external light is set to 300 lux (lx) to prevent color unevenness on the surface of the lenticular lens with antireflection film. The presence or absence was evaluated visually.

(result)
By the method of the present invention, lenticular lenses with an antireflection film (samples 24 and 25) formed by laminating four refractive index layers were obtained with high total light transmittance. In addition, the discharge state in all apparatuses was normal. On the other hand, the sample 26 to which an electric field was applied by a method other than the present invention was in a discharged state, but the total light transmittance was inferior to that of the present invention. Sample 27 was not discharged and a thin film was not obtained. The lenticular lens with the antireflection film (sample 28) formed by vapor deposition had a total light transmittance inferior to that of the present invention. In addition, color unevenness was confirmed by appearance evaluation. In the lenticular lens with the antireflection film (sample 29) formed by coating, the antireflection film was not uniformly formed.

It is sectional drawing which shows schematically the screen structure of a display apparatus. It is sectional drawing which shows schematic structure of an atmospheric pressure plasma discharge processing apparatus. It is a perspective view which shows the arrangement | positioning relationship between a stage electrode and each square tube type electrode. It is a perspective view which shows a stage electrode. It is a perspective view which shows a rectangular tube type electrode. It is sectional drawing which shows the modification of the atmospheric pressure plasma discharge processing apparatus of FIG.

Explanation of symbols

1 Front plate 2 Lenticular lens (Lenticular lens for display)
3 Fresnel lens 4 Base material 6 Antireflection film 10, 30 Atmospheric pressure plasma discharge treatment device 11 Stage electrode (first electrode)
12 Plasma discharge vessel 13 Square tube electrode (second electrode)
14 Gas supply port 15 Mesh 16 Discharge space 17 1st power supply 18 2nd power supply 19 1st filter 20 2nd filter

Claims (14)

A gas containing a thin film forming gas is supplied to the discharge space under atmospheric pressure or a pressure in the vicinity thereof, the high-frequency electric field is applied to the discharge space to excite the gas, and the substrate is exposed to the excited gas. A lenticular lens for display in which an antireflection film is formed on at least one surface of the substrate,
The high-frequency electric field is a superposition of the first high-frequency electric field and the second high-frequency electric field, and the frequency ω2 of the second high-frequency electric field is higher than the frequency ω1 of the first high-frequency electric field, and the first high-frequency electric field is And the second high frequency electric field strength V2 and the discharge start electric field strength IV satisfy V1 ≧ IV> V2 or V1> IV ≧ V2, and the output density of the second high frequency electric field is Is a lenticular lens for display, characterized in that is 1 W / cm ² or more.   The lenticular lens for display according to claim 1, wherein the discharge space includes a first electrode and a second electrode facing each other. 3. The lenticular lens for display according to claim 1, wherein an output density of the second high-frequency electric field is 50 W / cm ² or less. The lenticular lens for display according to claim 3, wherein the output density of the second high-frequency electric field is 20 W / cm ² or less. 5. The lenticular lens for display according to claim 1, wherein an output density of the first high-frequency electric field is 1 W / cm ² or more. 6. The display lenticular lens according to claim 5, wherein an output density of the first high-frequency electric field is 50 W / cm < ² > or less.   The lenticular lens for display according to any one of claims 1 to 6, wherein the first high-frequency electric field and the second high-frequency electric field are sine waves.   The display lenticular according to any one of claims 2 to 7, wherein the first high-frequency electric field is applied to the first electrode, and the second high-frequency electric field is applied to the second electrode. lens.   The lenticular lens for display according to any one of claims 1 to 8, wherein 90 to 99.9% by volume of the total gas supplied to the discharge space is a discharge gas.   The lenticular lens for display according to claim 9, wherein the discharge gas contains 50 to 100% by volume of nitrogen gas.   The lenticular lens for display according to claim 9 or 10, wherein the discharge gas contains a rare gas of less than 50% by volume.   The lenticular lens for display according to any one of claims 1 to 11, wherein the thin film forming gas contains at least one selected from an organometallic compound, a metal halide, and a metal hydride compound.   The organic metal compound contains at least one compound selected from an organosilicon compound, an organotitanium compound, an organotin compound, an organozinc compound, an organoindium compound, and an organoaluminum compound. Lenticular lens for display. The lenticular lens for display according to any one of claims 1 to 13, wherein the substrate has a thickness of 1 mm or more.

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