JPH0961549A - Optical clockface - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an optical clockface whose apparent color varies depending upon the observing angle so as to improve the decorativeness of the face by providing a color control layer which controls the optical paths of incident light and outgoing light and a coloring means layer. SOLUTION: The main body 13 of the optical clockface 11 is constituted by successively stacking a coloring means layer 14 and a light control layer 15 from the inside of the main body 11 of a clock. The layer 15 is formed by shaping the front face of a colorless transparent platy member into a three-dimensional shape (triangular pyramid, quadrangular pyramid, hexagonal pyramid, etc.) on one side or both sides. The layer 14 is formed by using a colored plastic plate which colors when the plate absorbs light. The external light made incident on the main body 11 from the outside is controlled in optical path by means of the layer 15 and the incident light in a certain direction is mostly reflected to the outside from the main body 11. The incident light in another direction is mostly transmitted through the main body. The outward color of the main body nearly becomes the color of the external light in the reflecting direction and the color of the colored light in the transmitting direction. Therefore, the decorativeness of the clockface 13 is improved, because the color of the clockface 13 varies depending upon the observing angle from the outside or the clockface 13 becomes invisible or visible.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an appearance of a timepiece, and more particularly to an appearance of a timepiece dial.

[0002]

2. Description of the Related Art Conventionally, a timepiece dial has been produced by using various appearance expressing techniques as one of the major factors that determine the appearance impression of the entire timepiece. In addition to the most commonly used painted dials, the dial appearance expression techniques that have been used up to now, such as Asahikou expression by special polishing of dials, appearance expression by special materials such as shell dials, pure gold dials, etc. There is a wide variety. However, there has never been a dial plate in which a certain appearance color changes uniformly depending on the angle when the dial plate is viewed from the outside, or is visible or disappears.

On the other hand, a dial appearance representation method in which the appearance color changes depending on the direction in which the dial is viewed has been proposed and realized by, for example, attaching a hologram sticker to the dial.

[0004]

However, in the above-mentioned hologram seal-attached dial plate, the appearance color changes depending on the angle at which the dial plate is viewed from the outside, but since the change is too severe, the dial plate remains calm. The appearance color cannot be realized. For this reason, it cannot be used in a preferable state as a timepiece exterior component, and it is not in a situation where the design can be diversified.

It is not possible to control the optical path such as reflection / diffusion of light, or the optical path, in which the appearance cannot be expressed in such a manner that a certain appearance color is uniformly changed or seen or disappears in these conventional dials. This is because the control of the visual angle dependence of the appearance color is ignored even if the control is performed. As a result, for example, in the case of a coated product, reflection that is close to complete diffusion occurs, and the appearance color that does not depend on the viewing angle is exhibited, and the appearance color does not change.

The object of the present invention with respect to these conventional problems is to express the entire dial with a specific appearance color, and to change the appearance color of the dial uniformly depending on the angle at which the dial is observed from the outside, or It is to provide a watch dial with high decorativeness that can be seen and disappeared.

[0007]

In order to solve the above-mentioned conventional problems, in the present invention, an optical control having a function of controlling the optical paths of incident and outgoing light from the inside to the surface of the timepiece main body. A timepiece dial is constructed by providing a layer and a coloring means layer for presenting an appearance color. The order relation between the light control layer and the coloring means layer does not matter. The coloring means layer is composed of a color body by light absorption, or is provided on the front side of the optical member for controlling an arbitrary wavelength range of incident light in the timepiece inward direction to a predetermined reflectance and an optical member. And a diffusion layer that diffuses the reflected light from the optical member and emits the diffused light to the front side. Of the light control layer or the coloring means layer,
The hourglass and logo are formed on the frontmost surface of the watch to form the watch dial.

How the conventional problems are solved in the dial plate of the present invention configured as described above will be described.

First, the case where the light control layer and the coloring means layer are laminated in this order from the outer side to the inner side of the watch body will be described. External light that enters from the outside of the timepiece body first enters the light control layer, and the light path of the light control layer is controlled by the incident direction at this time. Most of the light that enters the light control layer from one direction is reflected to the outside of the timepiece, and most of the light that enters the light control layer from another direction is transmitted. Since the light reflected by the light control layer is directly emitted to the outside of the timepiece, when the reflected light is observed outside, it has the same color as the outside light. On the other hand, the light transmitted through the light control layer reaches the coloring means layer. The light that has reached the coloring means layer is absorbed, reflected and transmitted in the specific wavelength range by the coloring means layer, of which the reflected light is the light having the appearance color. The reflected light (called colored light) from the coloring means layer passes through the light control layer and is emitted to the outside of the timepiece, so that the optical path is controlled again. Therefore, the colored light is emitted to the outside of the timepiece not only in the specular reflection direction but also in various directions. At this time, in the direction in which the external light is directly reflected, the external light directly reflected is stronger than the colored light, so that the colored light becomes inconspicuous, and as a result, the appearance color becomes almost the color of the external light. On the other hand, since the colored light is observed as it is in the direction in which the external light is not directly reflected, the appearance color is the color of the colored light. With such a function, the entire dial can be expressed in a specific appearance color, and the appearance color of the dial can be changed uniformly depending on the angle at which the dial is viewed from the outside, or can be seen or disappeared. A highly efficient clock dial can be obtained.

Next, the case where the light control layer and the coloring means layer are laminated in this order from the inner side to the outer side of the watch body will be described. When the light control layer and the coloring means layer are laminated in this order, the coloring means layer needs to be light-transmissive. External light entering from the outside of the timepiece body first enters the coloring means layer, and the coloring means layer absorbs, reflects, and transmits light in a specific wavelength range, and the reflected light becomes light having an appearance color. The reflected light (called colored light) from the coloring means layer is directly emitted to the outside of the timepiece. On the other hand, the light transmitted through the coloring means layer reaches the light control layer. The light incident on the light control layer is reflected or transmitted depending on the incident direction, as described above. The light that has passed through the light control layer proceeds to the inside of the watch as it is, and thus contributes little to the appearance. On the other hand, the light reflected by the light control layer goes out of the timepiece through the coloring means layer. Since the light reflected by the light control layer is originally the light that has passed through the coloring means layer and has entered the light control layer, there is almost no absorption or reflection when retransmitted through the coloring means layer. Therefore, when viewed from the angle at which reflection occurs in the light control layer, light that combines colored light and reflected light from the light control layer is visible, whereas when viewed from an angle at which reflection does not occur in the light control layer, only colored light is visible. To be observed. As a result, it is possible to realize a dial having different brightness and color depending on the angle at which the dial is observed.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION

(Embodiment 1) FIG. 1 is an external schematic view for explaining an embodiment in which the optical dial of the present invention is applied to a wristwatch. It is a figure. An optical dial 13 is provided in the watch case 12 of the watch body 11. The optical dial 13 will be described in detail. From the inner side of the timepiece body 11, the coloring means layer 14,
The light control layer 15 is laminated in this order. Then, hour characters and the like are printed on the front surface of the light control layer 15 to form the optical dial 13. Here, the light control layer 1
5 is obtained by processing the front surface of a colorless and transparent plate-shaped member such as glass or a plastic film into a three-dimensional shape. In addition, the light control layer 15 has any one of a triangular pyramid, a quadrangular pyramid, a hexagonal pyramid, a cone, a hemisphere, a lens shape, a cube prism, a cylindrical lens, a fisheye lens, and a lenticular on one or both surfaces of a colorless and transparent plate-shaped member. It can also be obtained by regularly arranging and processing the unevenness having the.

In the first embodiment, the light control layer 15 is set to 300
It was formed by honing the front surface of a white glass plate of μm with SiC powder corresponding to No. 120. At this time, the average roughness Ra of the honing surface is processed to be 1.5 to 1.7 μm and the average depth is about 7 μm, and the light transmittance is 81.
%Met. Further, as the coloring means layer 14, a commercially available colored plastic plate (SUMIPEX: trade name) which is a color developing body by light absorption was used.

Coloring means layer 1 prepared as described above
4, the light control layer 15 is laminated in this order to form the optical dial 13
The appearance quality of the dial was evaluated from the front side. In addition,
As the coloring means layer 14, those of bright blue, yellow and red were used. Here, as comparison targets for evaluation, a light-absorbing plastic dial plate (conventional example) and a dial plate in which a hologram seal was attached to a white plate (comparative example) were prepared.

As the evaluation criteria for the appearance expression, the acceptance criteria were that the entire dial could be recognized as one color (monochromaticity) and that the appearance color was clearly changed (appearance variability).
Table 1 shows the results.

[Table 1] As is clear from Table 1, both the above criteria cannot be satisfied in the conventional example and the comparative example. On the other hand, in Example 1 of the present invention, the appearance color of the dial could be recognized as one color, and the appearance color changed depending on the viewing angle of the dial. This means that the appearance color of the watch dial changes while maintaining a calm appearance.
As a design of the external appearance of the timepiece dial, it is possible to express in an unprecedented way.

In the first embodiment of the present invention described above, the colored plastic plate, which is a coloring material by light absorption, is used for the coloring means layer 14, but the coloring material by light absorption is not limited to the colored plastic plate. Any general color appearance product can be used, such as colored paper, cloth, shells, and plate-shaped substrates with color coating.

In the first embodiment of the present invention, the glass plate which has been subjected to the honing treatment is used as the light control layer 15, but a plastic material or the like may be used instead.
Further, the light control layer 15 is formed by a thin film forming method such as a spin coating method, a dipping method, or a vapor deposition method, and the coloring means layer 1 is formed.
It may be formed directly on the surface 4.

Also in the method of forming the light control layer 15, in addition to the honing treatment, a method of processing the surface of the transparent substrate into a fish-eye lens shape, a lenticular lens shape, or a Fresnel lens shape produces a diffusion layer having the same effect. It is confirmed that it can be obtained.

[0018]

【Example】

(Embodiment 2) FIG. 2 is a schematic external view for explaining an embodiment in which the optical dial of the present invention is applied to a wristwatch. It is a figure. An optical dial 23 is provided in the watch case 22 of the watch body 21. To describe the optical dial 23 in detail, the light control layer 24 and the coloring means layer 25 are laminated from the upper surface of the timepiece main body in the front direction of the timepiece. The coloring means layer 25 will be described in more detail. Layer 24
Interference filter as the optical member 251 from the side close to
The diffusion layers 252 are laminated in this order. Then, hour characters and the like are printed on the front surface of the diffusion layer 252 to form the optical dial 13. Here, the diffusion layer 252 can be formed by means of mechanically roughening the surface of a transparent body such as glass or a plastic film to make it rough, or modifying the surface of the plastic. Alternatively, a substance that has a white appearance in its molecular structure, such as Teflon or Delrin, may be used as the diffusion layer 252. Further, the diffusion layer 252 can also be formed by mixing calcium carbonate powder or the like in a binder and applying it to the surface of the transparent body, or mixing a scattering substance into the transparent body. As a simple means, paper or cloth may be used as the diffusion layer 252. The method of forming the light control layer 24 is the same as in the first embodiment.

In the second embodiment, the diffusion layer 252 has a thickness of 3
It was formed by honing one side of a 00 μm glass plate with SiC powder corresponding to No. 600. The average roughness Ra value of the honing surface at this time is 0.8 to 1.0 μm,
The average depth was 2.1 μm, and the light transmittance was 84%.
As will be described later, the applicable range was examined by adjusting the transmission degree of the diffusion layer 252 described above by changing the material and the honing process conditions.

FIG. 3 shows the light control layer 2 in the second embodiment.
4 is a cross-sectional schematic diagram of a light control layer 24 for explaining the configuration of FIG. Here, the light control layer 24 is the transparent substrate 241.
By machining one surface of the light control layer surface portion 2
42 is formed. The light control layer surface portion 242 is
It has a continuous prism shape in which quadrangular pyramids of 50 μm units are continuously spread in the XY direction.

In the second embodiment, TiO2 which is a high refractive index material (H) and S which is a low refractive index material (L).
An interference filter was created as the optical member 251 by using iO2. That is, five layers of a high-refractive index material and a low-refractive index material were appropriately laminated to form an optical member 251 having light control wavelengths of 570 nm, 435 nm, and 640 nm, respectively. Here, the control wavelength of light is 5
In the case of 70 nm, the reflection color is yellow, in the case of 435 nm, the reflection color is blue, and in the case of 640 nm, the reflection color is red. In addition to this, by adjusting the laminated material, the number of laminated layers, the film thickness, etc., it is possible to control not only the wavelength range through which light is transmitted, but also the reflectance in the wavelength region where light is reflected. Various optical members 251 having different light transmittances depending on the hue
Can be created as shown by optical theory.

The light control layer 24 formed as described above,
The coloring means layer 25 was laminated to form the optical dial 23, and the appearance quality of the dial was evaluated from the front side. The optical member 2
As 51, those whose reflection color is bright blue, yellow, and red were used. It is natural that the appearance color differs depending on the reflection color of the optical member 251, but the appearance expression in which the reflection color emerges from the inside of the dial is almost the same regardless of the reflection color. Here, as comparison targets for evaluation, a light-absorbing plastic dial plate (conventional example) and a dial plate in which a hologram seal was attached to a white plate (comparative example) were prepared.

As the evaluation criteria for the appearance expression, the acceptance criteria were that the entire dial could be recognized as one color (monochromaticity) and that the appearance color was clearly changed (appearance variability).
The results are shown in Table 2.

[Table 2] As is clear from Table 2, both the above criteria cannot be satisfied in the conventional example and the comparative example. On the other hand, in Example 2 of the present invention, the appearance color of the dial could be recognized as one color, and the appearance color changed depending on the viewing angle of the dial. This means that the appearance color of the watch dial changes while maintaining a calm appearance.
As a design of the external appearance of the timepiece dial, it is possible to express in an unprecedented way.

In the second embodiment of the present invention described above, the optical member 251 has a five-layer structure composed of a TiO2 film and a SiO2 film. However, as shown in the optical theory, the material and simple design change A variety of interference filters can be constructed and used. Although a glass plate that has been subjected to a honing treatment is used as the diffusion layer 252 here, a plastic material or the like may be used instead. Further, the diffusion layer 252 may be directly formed on the interference filter 251 by using a thin film forming method such as a spin coating method, a dipping method, or a vapor deposition method to form the coloring means layer 25.

As for the method of forming the diffusion layer 252, the diffusion layer having the same effect can be obtained by a method of processing the surface of the transparent substrate into a fish-eye lens shape, a lenticular lens shape, or a Fresnel lens shape in addition to the honing treatment. I have confirmed that it will be.

(Embodiment 3) FIG. 4 shows Embodiment 3 of the present invention.
FIG. 6 is a schematic cross-sectional view schematically showing the structure of the wristwatch according to the present invention.
Similarly to Example 2, the optical dial 31 was formed by stacking the coloring means layer 32 and the light control layer 33 in this order from the timepiece body side to the front side. The coloring means layer 32 will be described in detail. The high refractive index material layer as the optical member 321 and the diffusion layer 322 are sequentially laminated from the inside of the timepiece to the front side. Specifically, a diffusion layer 322 having a light transmittance of 90% was obtained by forming fine irregularities on one surface of a transparent plastic plate having a thickness of 0.2 mm. Then, a tantalum pentoxide thin film having a light refractive index of 2.1 is formed on the opposite surface of the transparent plastic plate to form a high refractive index material layer having a light transmittance of 80% and no wavelength selectivity. The optical member 321 is used. Furthermore, the thickness of 0.
The surface of a 3 mm glass plate was subjected to honing treatment with No. 800 SiC powder and then etched for 1 minute with a mixed solution of hydrofluoric acid and nitric acid to obtain a light control layer 33.

In the high refractive index material layer as the optical member 321 according to the third embodiment of the present invention, the reflectance of light is changed by changing the refractive index, so that the transmittance of light is adjusted. It is possible. Also,
Also for the diffusion layer 322, the light transmittance can be adjusted by selecting the honing material and the processing conditions. Further, the white diffusion layer 322 may be formed by means such as mechanically roughening the surface of a transparent body such as glass or a plastic film to make it rough as described above, or modifying the surface of the plastic. it can. Further, it is also possible to use, as the diffusion layer 322, a material that has a white appearance structurally, such as Teflon, Delrin, paper or cloth. Furthermore, by mixing calcium carbonate powder or the like in a binder and applying it on the surface of the transparent body, or by mixing a scattering substance into the transparent body, the transparent substrate surface is shaped like a fisheye lens,
The diffusion layer 322 can also be formed by processing into a lenticular lens shape or a Fresnel lens shape. Alternatively, the diffusion layer 322 may be directly formed on the optical member 321 by using a thin film forming method such as a spin coating method, a dipping method, or a vapor deposition method. Furthermore, when the respective constituent elements are joined by an adhesive, it is possible to include a material having the function of the diffusion layer as described above in the adhesive.

Coloring means layer 32 prepared as described above
And the light control layer 33 are laminated in this order to form the optical dial 3
1 was constructed and a wristwatch was manufactured. Then, the appearance quality of the timepiece dial was evaluated from the front side of this wristwatch. here,
As a comparison target for evaluation, a color absorption type plastic dial (conventional example: gray) was prepared.

As the evaluation criteria for appearance expression, the acceptance criteria were that the entire dial could be recognized as one color (monochromaticity) and that the appearance brightness was clearly changed (appearance variability). Since the appearance of the dial according to Example 2 of the present invention and the appearance of the conventional example are both achromatic, the criterion for the appearance variability evaluation was not the color but the brightness. Table 3 shows the results.

[Table 3] As is apparent from Table 3, both of the above criteria cannot be satisfied in the conventional example. On the other hand, in the embodiment of the present invention, the dial appearance color can be recognized as one color,
Moreover, the brightness changed depending on the angle at which the dial was viewed. This keeps the appearance of the watch dial calm,
This means that the appearance color changes, and it allows for unprecedented expression in the design of the appearance of the watch dial.

In the third embodiment, the optical member 32 is used.
Although a tantalum pentoxide thin film having a light refractive index of 2.1 was used as 1, a material such as aluminum oxide or titanium oxide having a light refractive index of 1.6 or more and not absorbing light in the visible region may be used. For example, it can be used as the optical member 321. Further, the high refractive index layer as the optical member 321 is not limited to the thin film on the plastic plate, and may be formed of the high refractive index material itself.

(Embodiment 4) FIG. 5 shows Embodiment 4 of the present invention.
FIG. 6 is a schematic cross-sectional view schematically showing the structure of the wristwatch according to the present invention.
Similarly to Example 1, the optical dial 41 was formed by laminating the coloring means layer 42 and the light control layer 43 in this order from the timepiece body side to the front side. As the coloring means layer 42, a commercially available light-absorbing plastic plate was used as in Example 1. The light control layer 43 was formed as follows.

First, a mother mold for forming the light control layer 43 was prepared by the following steps. First, after forming a gold film on a (100) Si wafer, a photolithography process,
The gold film was removed into a round shape having a diameter of 5 μm at a pitch of 30 μm by passing through an etching process. Then, Si
By immersing the wafer in a mixed solution of concentrated hydrofluoric acid, nitric acid, and acetic acid, isotropic S
Etch the i-wafer. After that, when the remaining gold film is removed, a mother mold in which hemispherical concave portions are regularly arranged is completed. The diameter of the recess depends on the etching time,
After etching for about 30 minutes, a mother type was obtained in which hemispherical parts having a diameter of about 25 μm were continuously and regularly arranged in the XY directions.

An electric mold is prepared from the mother mold prepared as described above, PMMA resin is cast on the coloring means layer 42, and the hemispherical shape is transferred by using the electric mold to control the light control layer 43. Was formed. Next, the hourglass and the logo were printed on the front side of the light control layer 43 to form the optical dial 41.

A wristwatch was manufactured by constructing the optical dial 41 as described above. Then, from the front side of this wristwatch, the appearance quality of the same watch dial as in Example 1 was evaluated. As a result, almost the same results as in Example 1 were obtained, and the change in appearance color was sharper and clearer than in Example 1. This is a difference caused by the fact that the optical path control effect of the light control layer 43 of Example 4 is clearer and steeper than that of Example 1.

(Embodiment 5) In Embodiment 5 and Embodiment 6 which will be described later, the coloring means layer, which is an essential requirement of the present invention, has a predetermined wavelength range within a predetermined range with respect to incident light directed inward of the timepiece. Regarding the conditions to be satisfied by the diffusion layer in the case of comprising an optical member for controlling the reflectance and a diffusion layer which is provided on the front side of the optical member and diffuses the reflected light from the optical member to emit to the front side We examined and optimized it.

When the coloring means layer is composed of the optical member and the diffusing layer, the conditions that the diffusing layer must satisfy in order to obtain the coloring means layer having excellent appearance quality are to secure the scattering performance and to obtain a high transmittance. It is compatible. That is, light incident from the outside passes through the diffusion layer, and is partially reflected by the optical member and the rest is transmitted. The light reflected from the optical member is scattered by the diffusion layer, and as a result, the scattered light returns to the outside observer and a uniform color is confirmed. At this time, if the transmittance of the diffusion layer decreases, the amount of light reaching the optical member decreases, and as a result, the amount of light reflected from the optical member also decreases. Since the reflected light passes through the diffusion layer once again and is emitted to the outside, the expressiveness of the appearance color is significantly reduced when the transmittance of the diffusion layer is reduced. As a result of confirmation by experiments, it is desirable that the transmittance of the diffusion layer is 80% or more, preferably 90% or more.

Various conditions for obtaining a diffusion layer having such characteristics are examined, and white powder is dispersed as a light scattering substance in a colorless and transparent plastic material, or the refraction of the plastic material is mixed. It has been found that a white diffusion layer having a high transmittance of 80% or more can be obtained by dispersing and mixing transparent particles having a refractive index different from the refractive index.

On the other hand, the scattering performance is also examined,
The compatibility range with the condition range showing high transmittance was estimated. Here, the ratio of the light transmitted through the diffusion layer is defined as the total transmittance, the projection optical fiber and the light receiving fiber of the same size are arranged at a certain distance, and the light reaching the light receiving fiber when the diffusion layer is inserted between them The diffusion coefficient = (total transmittance-straight transmittance) / total transmittance was defined with the ratio as the straight transmittance, and the correlation with the scattering performance was investigated. As a result, it was found that the diffusion performance satisfying the appearance quality can be obtained with the diffusion layer satisfying the diffusion coefficient ≧ 0.3. Together, these examination results showed that a diffusion layer having both a high transmittance of 80% or more and a diffusion coefficient ≧ 0.3 can be obtained.

Specific embodiments will be described below with reference to the drawings.

FIG. 6 is for explaining the fifth embodiment of the case where the optical dial of the present invention is applied to a wristwatch.
It is a cross-sectional schematic diagram which showed typically the structure near a dial.
The watch case 52 of the watch body 51 is provided with an optical dial 53. The optical dial 53 is formed by laminating a light control layer 54 and a coloring means layer 55 from the inside of the timepiece. The light control layer 54 is the light control layer 43 in the fourth embodiment of the present invention.
Is the same as The coloring means layer 55 is the light control layer 54.
The optical member 551 and the diffusion layer 552 are laminated from the side. Then, hourglasses and the like are printed and formed on the front surface of the diffusion layer 552 to form a wristwatch. Here, a high refractive index material layer is used as the optical member 551. Specifically, 170 nm of SiO 2 and 54 n of TiO 2 are formed on a transparent glass substrate.
An achromatic reflective product formed by sequentially performing vapor deposition was used.

FIG. 7 is a schematic sectional view of the diffusion layer 552. The diffusion layer 552 is a colorless transparent plastic material 55.
21, for example, PMMA (methyl methacrylate) resin is used, in which a light scattering material 5522, for example, 20 μm is used.
10 PS (polystyrene) particles having a particle size of about m
It was manufactured by mixing and mixing in a weight percentage of about 0.25 mm and then molding it to a thickness of 0.25 mm. Here, since both the PMMA and PS materials themselves are transparent, they show high light transmissivity. Further, since the refractive index of light is different from 1.49 for PMMA and 1.59 for PS, scattering due to the difference in refractive index is caused. Occurs. As a result, in the above structure, the transmittance ≈ 91% and the diffusion coefficient ≈ 0.
The performance of 6 was obtained and it was sufficiently usable as a diffusion layer.

It has been confirmed that the optical dial prepared as described above exhibits excellent monochromaticity in appearance and variability in appearance color.

In the fifth embodiment, the diffusion layer 552 is
Its main purpose is to efficiently scatter the reflected light from the optical member 551 so that it can be observed from the outside as a uniform appearance color. In fact, with the above configuration, it was recognized as a gray (gray) appearance color, and in combination with the metallic texture peculiar to reflected light, it showed excellent appearance quality as a dial for a wristwatch.

In the fifth embodiment described above, the diffusion layer 552
PMMA as a plastic material 5521 for forming
Although PS was selected as the light scattering material 5522, it is of course possible to combine it with other materials. For example, PMM
As the light scattering substance dispersed and mixed in A, the refractive index of light is 1.
63 polysulfone, PET with a refractive index of 1.58
(Polyethylene terephthalate) can be used.

On the contrary to Example 5, the same effect can be obtained by dispersing and mixing a substance having a low light refractive index in a substance having a high light refractive index. For example, the refractive index of light is 1.55
PVA (polyvinyl acetate) having a light refractive index of 1.46 may be dispersed and mixed in 1.61 epoxy resin. Further, the light transmittance and the diffusion coefficient greatly change depending on the concentration and particle size of the light scattering substance in the plastic material. In this Example 5, the concentration and particle size of PS dispersed and mixed in PMMA were examined, and the concentration range was 5 to 40% by weight.
By adjusting the particle size range to 5 to 50 μm, 8
A diffusion layer 552 having a light transmittance of 0% or more and simultaneously satisfying a diffusion coefficient of 0.3 or more was obtained. By changing the light transmittance and diffusion coefficient in this way, it is possible to express the appearance in a wide range from whitish light gray with strong scattering properties to metallic gray with strong transparency.

Further, in FIG. 6, when an interference filter is formed as the optical member 551 instead of the high refractive index material layer, the difference in performance of the diffusion layer 552 is more clearly expressed as the difference in appearance quality. . That is, when a high refractive index material layer is used, reflected light having no wavelength dependence in the visible region is scattered by the diffusion layer 552 and emitted to the outside.
Even if the transmission characteristics of the diffusion layer 552 are inferior and the white turbid component is superimposed, the difference does not become large as a result. On the other hand, when a specific color component is reflected by the interference filter layer, if the white turbid component of the diffusion layer 552 is present, it will be observed as a muddy, dirty color. For this reason, when expressing a color appearance, a diffusion layer that ideally has a scattering property and transmits almost 100% of light is desirable, but in reality, since there is interface reflection and the like, 100% of light should be transmitted. Is impossible. Therefore, the diffusion layer 552 is
It is desirable to have as high a transmittance as possible.

(Embodiment 6) FIG. 8 is for explaining Embodiment 6 when the optical dial of the present invention is applied to a wrist watch, and is a cross-sectional view schematically showing the structure near the dial. It is a schematic diagram. The watch case 62 of the watch body 61 is provided with an optical dial 63. The optical dial 63 is constructed by laminating a light control layer 64 and a coloring means layer 65 from the timepiece body side. The light control layer 64 is the same as the light control layer 43 in the fourth embodiment of the present invention. The coloring means layer 65 is
An optical member 651 and a diffusion layer 652 are laminated from the light control layer 64 side. Then, a timepiece or the like is printed on the front surface of the diffusion layer 652 to form a wristwatch. Here, a high refractive index material layer is used as the optical member 651. Specifically, by depositing a titanium oxide thin film having a light refractive index of 2.3 on one surface of a transparent glass substrate by about 60 nm, a high refractive material having an achromatic appearance with a light reflectance of approximately 25%. Layers were formed.

FIG. 9 is a schematic sectional view of the diffusion layer 652. Explaining the method for manufacturing the diffusion layer 652, first, one surface of the glass substrate 6521 is subjected to honing treatment with No. 2000 equivalent Sic powder to obtain an average roughness Ra≈.
A mechanical uneven shape of 0.02 μm and average depth ≈0.1 μm is formed on the surface. The light transmittance at this time was 91%, but since the diffusion coefficient was around 0.1, it could not be used as it is because the light scattering performance was low. Then, the surface subjected to the honing treatment was subjected to etching treatment in hydrofluoric acid for about 10 seconds to obtain a convex / concave portion 6522 having an improved light transmittance of 91.5% and a diffusion coefficient of 0.4. This value indicates that the diffusion layer 652 can be sufficiently used.

It has been confirmed that the optical dial prepared as described above has excellent monochromaticity in appearance and variability in appearance color.

Also in the sixth embodiment, the diffusion 652 efficiently scatters the reflected light from the optical member 64 and makes it possible to observe it as a uniform appearance color from the outside, like the fourth embodiment and the like. The main purpose is. In fact, with the above structure, a gray color having no wavelength dependency in the visible region was recognized as an appearance color, and the appearance quality was excellent as a dial for a wristwatch.

The transmittance and diffusion coefficient of the diffusion layer 652 can be changed by changing the honing conditions. For example, as a result of examining various conditions of the honing process using Sic Nos. 120 to 4000, No. 400 to 2000 can be combined with the etching process.
It was found that the light transmittance and the diffusion coefficient were satisfied at the same time up to the vicinity. By adjusting the conditions of the honing process in this manner, it is possible to express the appearance in a wide range from whitish gray with strong scattering properties to gray with strong transparency.

As described above, the light transmittance can be improved by increasing the number of Sic only by the honing process, but the diffusion coefficient is reduced accordingly, so that
Scattering performance deteriorates and both specifications cannot be satisfied at the same time. Therefore, by adding the etching treatment, the light transmittance and the diffusion coefficient were further increased, so that the condition of the honing treatment can be satisfied in a wide range as described above.

Although there are still many unclear points about the effect of the etching treatment, the sharp uneven shape after the honing treatment is
It is considered that the above improvement was obtained by aligning the shape with a rounded and uneven shape.

The uneven shape varies depending on the condition of the honing process. By the way, the surface subjected to the etching treatment after the honing treatment with SiC No. 800 was an aggregate of rounded irregularities with a size of about 50 μm. In addition, SiC200
After the honing treatment with No. 0, it was confirmed that the surface subjected to the etching treatment was composed of an assembly of rounded irregularities having a size of several μm to 10 μm.

In the sixth embodiment, honing means is used as a method for mechanically roughening the surface of a transparent body such as a glass substrate to make it a rough surface, but other machining methods or the like can also be used. .

In FIG. 8, when the interference filter layer is applied as the optical member instead of the high refractive index material layer, the difference in characteristics of the diffusion layer 652 is more clearly expressed as the difference in appearance quality. That is, when the high-refractive index material layer is used, since the reflected light having no wavelength dependence in the visible region is scattered by the white diffusion layer and is observed from the outside, the transmission performance of the diffusion layer 652 is inferior. As a result, the difference does not increase even if the cloudy component is superposed. However, when a specific color component is reflected by the interference filter layer,
Due to the white turbidity component of the diffusion layer 652, a messy color is observed. For this reason, when the color appearance is expressed by the interference filter layer, it is desirable to have a scattering property and adjust the transmittance as high as possible.

In the above-mentioned Examples 5 to 6, only representative materials were shown for each of them, but the other materials also have a light transmittance of 80% or more and a diffusion coefficient of 0.3 or more. It is possible to form a diffused layer.
Also, if the transmittance characteristics are the same, the amount of total reflected light emitted to the outside is the same, and by varying the diffusion coefficient, it is possible to control the strength of the viewing angle dependency and the glossiness, so various appearance expressions are possible. .

If the diffusion layers of Examples 5 to 6 described above are used, both high transmittance and scattering performance can be achieved, so that a timepiece dial having a change in appearance brightness / quality and color can be easily supplied. For this reason, it becomes possible to apply to various purposes using an appearance color expression different from the conventional one.

(Embodiment 7) In this embodiment 7, the conditions to be satisfied by the light control layer in the optical dial in which the brightness / quality of appearance and the variability of color are compatible at a high level are examined and optimized. Planned. The condition to be satisfied by the light control layer in order to obtain an optical dial with excellent appearance quality is to control the optical paths of incident and reflected light to give a sharp visual angle dependence to the appearance color of the entire dial. . In other words, it is necessary to add a function that allows the appearance color of the dial to be seen or disappeared depending on the angle at which the dial is observed from the outside.

In the present invention, the light control layer functions as follows. That is, the light in the specific wavelength range reflected by the optical member is diffused by the diffusing layer to become light having a small viewing angle dependency and is emitted to the outside. On the other hand, light in the wavelength range transmitted through the optical member reaches the light control layer. However, by processing one side or both sides of the light control layer three-dimensionally, the optical paths of incident and reflected light in the light control layer can be arbitrarily set. Can be controlled. In particular, light that enters the light control layer from a particular incident direction can be totally reflected. Therefore, when the dial is observed from the angle direction, the reflected light from the optical member and the light totally reflected after passing through the optical member are combined to become white light. The light of the part which is incident on the light control layer and is not totally reflected reaches the inside of the timepiece through the light control layer and is partially diffused inside the timepiece to be emitted to the outside, but the amount of light emitted is very small. It does not affect the appearance color even when combined with the reflected light from the optical member. In this way, it is possible to realize a new dial decoration expression that cannot be expressed by the conventional dial. Therefore, when viewed from the outside, the inside of the watch becomes difficult to recognize.

In order to obtain a light control layer having such characteristics, various studies have been conducted, and a surface of a plate-like member, such as a glass plate or a plastic plate, which is colorless and transparent at least in the visible region, in contact with the optical member is It was found that the light control layer in which the appearance color changes very sharply depending on the conditions can be obtained by processing the three-dimensional shape.

Specific embodiments will be described below with reference to the drawings.

FIG. 10 is a view for explaining Embodiment 7 in which the optical dial of the invention is applied to a wristwatch.
It is a cross-sectional schematic diagram which showed typically the structure of a dial. First
FIG. 1 is a schematic cross-sectional view schematically showing the surface shape of a light control layer which is a constituent element of the optical dial. Light control layer 7
The front surface of No. 4 is surface-processed so as to become a light control layer surface portion 77 having a shape as shown in FIG.
It is fixed inside. On the front surface of the light control layer 74, a coloring means layer 75 in which an optical member 751 and a diffusion layer 752 are laminated in this order is arranged. Then, the diffusion layer 752
An optical dial 72 was constructed by also using the front face of the as a dial, and a wristwatch was manufactured.

Here, the light control layer 74 has a light control layer surface portion 77 formed by machining one surface. The light control layer surface portion 77 has a continuous prism shape in which 50 μm-unit quadrangular pyramids are continuously spread in the XY direction. Further, as the optical member 751, a titanium oxide thin film having a light refractive index of 2.3 is used.
A high refractive index material layer formed by depositing a film having a thickness of about 60 nm on one surface of a C (polycarbonate) plate is used. The diffusion layer 752 is a mother type obtained by subjecting a glass plate to a honing treatment with SiC powder corresponding to No. 1000 and then etching the mixture in a mixed solution of hydrofluoric acid and nitric acid to form the optical member 751 on the PC plate. An ultraviolet-curable PMMA (methyl methacrylate) resin was cast-transferred onto the non-coated surface.

The apex angle of the quadrangular pyramid of the light control layer surface portion 77 in the optical dial thus prepared is 70 ° to
When the appearance color variability was confirmed by shaking in the range of 120 °, all the light control layers showed good appearance variability.

Although the shape of the light control layer surface portion 77 in the seventh embodiment of the present invention is a quadrangular pyramid, a hemispherical shape like the light control layer 43 in the fourth embodiment of the present invention similarly provides good appearance changeability. Is as described in Example 4. When the surface shape of the light control layer that gives good appearance variability like these was experimentally studied, a triangular pyramid, a quadrangular pyramid, a hexagonal pyramid, a cone, and
It has been found that it is sufficient to regularly arrange and process the unevenness having any one of a hemisphere shape, a lens shape, a cube prism, a cylindrical lens, a fisheye lens and a lenticular lens. By performing these special arrangement processing,
It is possible to obtain better appearance changeability than that of the light control layer which is generally subjected to three-dimensional processing.

In Example 7, the light control layer surface portion 77
Further, although the quadrangular pyramids are continuously arranged in the X-Y direction, they may be arranged in the r- [theta] direction or shifted by half pitch. This is exactly the same when the surface shape of the light control layer is a shape other than a quadrangular pyramid. In addition, it was confirmed that the visual angle dependence of the appearance color was randomly approached by intentionally creating and transferring an electroforming mold having a random arrangement. Further, as a substrate for forming the optical member and the diffusion layer, P
Many plastic materials can be used in addition to the C plate, and the molding method may be a method other than injection.

Although the high refractive index material layer is used as the optical member in Example 7, an interference filter layer may be used. In this case, a specific color will be observed from the outside, but since the reflected light from the inside of the watch is hardly recognized from the outside due to the function of the light control layer, the intended color is reproduced faithfully and uniformly. It Moreover, due to the optical path controllability of the light control layer itself, a steep viewing angle dependence appears in the appearance color, and it becomes possible to express the appearance of a timepiece dial that has never existed before.

As described above, if the light control layer shown in Example 7 is used, the appearance color is maintained while maintaining a uniform appearance reflection color in order to achieve both the disturbance of the internal image of the timepiece and the optical path controllability. Since it is possible to impart a steep viewing angle dependency, it becomes possible to apply to various purposes using an appearance color expression different from the conventional one.

According to the present invention, it has become possible to express the appearance of a timepiece dial that has never been seen before. In all the embodiments of the present invention, only the structure in which the entire timepiece dial has a single color has been described for the sake of simplicity. However, the optical member has a multicolored configuration, or only a part of the dial has a single color. It goes without saying that the invention can be easily applied.

[0071]

According to the present invention, it is possible to express a dial that has never existed before while maintaining a good appearance quality as a wristwatch, and it is possible to express a variety of bright appearance colors excellent in appearance quality. . It is also possible to draw a picture or a character on the timepiece dial of the present invention, or to further provide a color filter. From these facts, the degree of freedom in design is greatly expanded compared to the past, and it becomes possible to apply to more versatility than ever before.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a wristwatch that is an embodiment of the present invention.

FIG. 2 is a schematic sectional view of a wristwatch which is a second embodiment of the present invention.

FIG. 3 is a schematic sectional view of a light control layer in a second embodiment of the present invention.

FIG. 4 is a schematic sectional view of a wristwatch which is a third embodiment of the present invention.

FIG. 5 is a schematic sectional view of a wristwatch which is a fourth embodiment of the present invention.

FIG. 6 is a schematic sectional view of a wristwatch which is a fifth embodiment of the present invention.

FIG. 7 is a schematic sectional view of a diffusion layer according to a fifth embodiment of the present invention.

FIG. 8 is a schematic sectional view of a wristwatch which is a sixth embodiment of the present invention.

FIG. 9 is a schematic sectional view of a diffusion layer in a sixth embodiment of the present invention.

FIG. 10 is a schematic sectional view of a wristwatch which is a seventh embodiment of the present invention.

FIG. 11 is a schematic sectional view showing a surface shape of a light control layer in a seventh embodiment of the present invention.

[Explanation of symbols]

 11 watch body 12 watch case 13 optical dial 14 coloring means layer 15 light control layer

Claims (10)

[Claims] 1. An optical dial for a timepiece, which comprises an optical dial on the upper surface of a watch body, wherein the optical dial is:
An optical dial for a timepiece, comprising a light control layer for controlling an optical path for incident light and emitted light, and a coloring means layer. 2. The optical dial plate for a timepiece according to claim 1, wherein the coloring means layer is a color developing body by absorbing light. 3. The coloring means layer is provided with an optical member for controlling an arbitrary wavelength range of incident light in the direction of the timepiece main body to have a predetermined reflectance, and provided on the front side of the optical member. The optical dial plate for a timepiece according to claim 1, comprising a diffusion layer that diffuses the reflected light of and diffuses to the front side of the timepiece. 4. The optical dial plate for a timepiece according to claim 1, wherein the light control layer is formed by processing the front surface of a colorless and transparent plate member into a three-dimensional shape. 5. The light control layer, on one or both surfaces of a colorless and transparent plate-shaped member, has a triangular pyramid, a quadrangular pyramid, a hexagonal pyramid, a cone,
The optical dial for a timepiece according to claim 1, wherein irregularities having any one of a hemisphere shape, a lens shape, a cube prism, a cylindrical lens, a fisheye lens, and a lenticular are regularly arranged and processed. 6. The optical dial plate for a timepiece according to claim 3, wherein the optical member is an interference filter or a dichroic filter. 7. The optical dial plate for a timepiece according to claim 3, wherein the optical member is made of a high refractive index material having a light refractive index of 1.6 or more. 8. The optical member comprises a low refractive index material having a refractive index of 1.5 or less and a high refractive index material having a refractive index of 1.6 or more laminated on a transparent base material in a visible wavelength range. The optical dial for a timepiece according to claim 3, which has a thin film structure of layers. 9. The diffusion layer comprises a colorless transparent plastic material in which white powder as a light-scattering substance or transparent particles having a refractive index different from the refractive index of light of the plastic material are dispersed and mixed. The optical dial plate for a timepiece according to any one of claims 3 to 5, wherein 10. The diffusion layer comprises a colorless transparent body having a rough surface.
Optical dial for timepiece described in.