JP2020101380A - Power generator with solar battery and watch with solar battery - Google Patents

Abstract

To improve power generating efficiency of a solar battery 30, and suppress reduction of aesthetic property.SOLUTION: A wrist watch 1 has: a dial plate 10 including a light color part W and a dark color part BK having higher light transmissivity than light color part W, which a user can view; and a solar battery 30 which generates power by making light transmitted through the dial plate 10 be incident into the battery. In the solar battery 30, a power generation amount of power generation by incidence of a blue light component B and a green light component G is larger than power generation by incidence of red light component R out of visible light, and the dial plate 10 includes an absorption layer 11 which absorbs the red light component R at higher light absorption rate than light absorption rate to the blue light component B and the green light component G in the dark color part BK.SELECTED DRAWING: Figure 2

Description

The present invention relates to a power generator with a solar cell and a timepiece with a solar cell.

BACKGROUND ART Conventionally, there is known a wristwatch including a solar cell that generates electric power when light transmitted through a dial is incident. It is known that as a color characteristic, light white is easy to reflect light, and dark black is easy to absorb light. Therefore, the dial plate is likely to reflect light in a light-colored area such as white, while absorbing light in a dark-colored area such as black. For example, when the hour character provided on the dial is made of a black material, most of the light incident on the hour character is absorbed and does not reach the solar cell. Patent Document 1 discloses a configuration in which a hole is provided in an hour-character portion on a dial and a light-transmitting material containing a pigment or the like is provided so as to seal the hole.

Japanese Unexamined Patent Publication No. 2000-131463

In the configuration of Patent Document 1, since light is transmitted in the hour portion, the amount of light incident on the solar cell can be increased and the amount of power generation can be improved. However, the solar cell can be seen through at the hour portion, which may reduce the aesthetics. On the other hand, if the proportion of the pigment contained in the light transmitting material is increased so that the solar cell cannot be seen through, the aesthetics will be improved, but the amount of light reflected at the hour portion will increase and The amount of incident light is reduced.

In addition, it is known that the solar cell used in the wristwatch as disclosed in Patent Document 1 has a property of easily absorbing blue and green light components of visible light and hardly absorbing red light components. Therefore, the red light component that passes through the dial and enters the solar cell is reflected on the surface of the solar cell without contributing to the power generation of the solar cell. As described above, the red light component is reflected by the solar cell, so that the reddish color light leaks from the transmissive region of the dial, which may deteriorate aesthetics.

The present invention has been made in view of the above problems, and an object thereof is to improve the power generation efficiency of a solar cell and to suppress deterioration of aesthetics.

The invention disclosed in the present application to solve the above-mentioned problems has various aspects, and the outline of representative aspects thereof is as follows.

(1) One or a plurality of visible members visible to the user, which include a light-colored portion and a dark-colored portion having a light transmittance higher than that of the light-colored portion, and the light transmitted through the visual-recognition member causes power generation. A solar cell, wherein the solar cell has a second wavelength band different from the first wavelength band of visible light, rather than power generation by incidence of a first light component of the first wavelength band of visible light. The power generation amount of power generation by the incidence of the second light component in the wavelength band is large, and the visual recognition member has a light absorption rate higher than at least the light absorption rate for the second light component in the dark color portion. A power generation device with a solar cell, which includes an absorption layer that absorbs the light component of.

(2) In (1), the power generation device with a solar cell in which the absorption layer includes a color filter.

(3) The power generator with a solar cell according to (1) or (2), wherein the absorption layer has a haze value of 0 or more and 3 or less.

(4) One or a plurality of visible members visible to the user, which include a light-colored portion and a dark-colored portion having a light transmittance higher than that of the light-colored portion, and light transmitted through the visual-recognition member is incident to generate power. A solar cell, wherein the solar cell has a second wavelength band different from the first wavelength band of visible light, rather than power generation by incidence of a first light component of the first wavelength band of visible light. A large amount of power is generated by the incidence of the second light component in the wavelength band, and the visual recognition member has a polarizing plate that transmits only the light component polarized in a specific direction in the dark color portion, and the visual recognition surface of the polarizing plate. And a retardation plate which is provided on the surface opposite to the above and which imparts a phase difference of π/2 to the incident light component.

(5) In any one of (1) to (4), the first wavelength band is a red wavelength band, and the second wavelength band includes at least a blue wavelength band or a green wavelength band. Power generator.

(6) The power generation device with a solar cell according to any one of (1) to (5), wherein an antireflection film is provided on at least a visible surface of the dark-colored portion of the visible member.

(7) The power generation device with a solar cell according to any one of (1) to (6), wherein an antireflection film is provided on at least a surface of the visual recognition member opposite to the visual recognition surface of the dark portion.

(8) A timepiece with a solar cell including the power generation device with a solar cell according to any one of (1) to (7), wherein the visual confirmation member is a dial or a pointer for moving hands on the dial. A solar-powered watch that is either or both of them.

(9) In (8), the dark color part is a timepiece with a solar cell including at least an hour character provided on the dial.

(10) In (9), the solar cell includes a power generation region in which power is generated when light is incident and a non-power generation region in which power is not generated. A timepiece with a solar cell provided so that the non-power generation region does not overlap the time character.

According to the aspects (1) to (10) of the present invention, the power generation efficiency of the solar cell can be improved and the aesthetics can be reduced.

It is the top view which looked at the dial of the wristwatch concerning 1st Embodiment from the visual recognition side. It is a schematic cross section which shows typically a part of cross section of the wristwatch which concerns on 1st Embodiment. It is a figure which shows the haze value of a color filter, and evaluation of whether the absorption layer provided with the color filter can be adopted for the wristwatch according to the first embodiment. It is a figure which shows the light transmittance for every wavelength in the color filter with which the absorption layer of 1st Embodiment is provided. It is a schematic cross section which shows typically a part of cross section of the wristwatch which concerns on the 1st modification of 1st Embodiment. It is a schematic cross section which shows typically a part of cross section of the wristwatch which concerns on the 2nd modification of 1st Embodiment. It is the top view which looked at the dial of a wristwatch concerning the 3rd modification of a 1st embodiment from the visual recognition side. It is a schematic cross section which shows typically a part of cross section of the wristwatch concerning the 3rd modification of 1st Embodiment. It is a schematic cross section which shows typically a part of cross section of the wristwatch which concerns on 2nd Embodiment. It is a top view which shows typically the wristwatch which concerns on the 1st modification of 2nd Embodiment. It is a schematic cross section which shows typically a part of cross section of the wristwatch which concerns on the 1st modification of 2nd Embodiment. It is a top view which shows typically the wristwatch which concerns on the 2nd modification of 2nd Embodiment. It is a schematic cross section which shows typically a part of cross section of the wristwatch which concerns on the 2nd modification of 2nd Embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a plan view of the dial of the wristwatch according to the first embodiment as viewed from the viewing surface side. The visible surface side is the side that the user visually recognizes when using the wristwatch 1. Further, in the following description, the side opposite to the visible surface side will be referred to as the back surface side. Further, the surface on the visible surface side of each substrate, each layer, and the like of the wristwatch 1 is referred to as a visible surface or an upper surface, and the surface on the opposite side is referred to as a back surface or a lower surface.

The wristwatch 1 includes a dial 10 that is a visual recognition member and a solar cell 30. The chain double-dashed line in FIG. 1 indicates the outer shape and the division line D of the solar cell 30 arranged on the back surface side of the dial 10. Although not shown in FIG. 1, pointers may be arranged on the dial 10 so as to move the hands.

On the visible surface side of the dial 10, a time character 50 indicating the time, a logo mark indicating a brand name, a product name, and the like, and a display unit 60 for displaying other patterns and the like are provided. In FIG. 1, Roman letters I to XII are shown as the hour characters 50, and the display unit 60 displays "ABCDEFG" indicating the brand name and a mark composed of a black triangle and a quadrangle.

In the following description, an area of the dial 10 that the user recognizes as white is called a light color portion W, and an area that the user recognizes as black is called a dark color portion BK. In the wristwatch 1 shown in FIG. 1, a region on which the hour characters 50, the display unit 60, and the like are provided on the visible surface of the dial 10 is a dark color portion BK, and a region other than the dark color portion BK is a light color portion W. .. FIG. 1 shows an example of the dial 10 in which approximately 86% of the visible surface is the light color portion W and approximately 14% is the dark color portion BK.

The shape and design of the dial 10 shown in FIG. 1 is an example, and the present invention is not limited to this, and may include at least a light color portion W and a dark color portion BK.

FIG. 2 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the first embodiment. In FIG. 2, each arrow indicates a blue light component B (second light component in the second wavelength band) and a green light component G (second light in the second wavelength band) of visible light. Component) and a red light component R (first light component of the first wavelength band), and the direction of the arrow indicates the traveling direction of light. Further, the light quantity of each light is schematically shown in correspondence with the length of the arrow. That is, it is assumed that the longer the arrow, the greater the amount of light. In FIG. 2, part of the light that has entered the dial 10 from the viewing surface side is reflected or absorbed by the dial 10, so the amount of light that has passed through the dial 10 is incident on the dial 10. It is shown that it becomes less than the amount of light. The same applies to FIG. 5 and FIG. 6 described later.

As shown in FIG. 2, the wristwatch 1 has a solar cell 30 on the back side of the dial 10.

The solar cell 30 generates power when the light transmitted through the dial 10 is incident. Specifically, the solar cell 30 includes a semiconductor layer made of silicon or the like, and an electrode layer arranged on at least one of the upper surface and the lower surface of the semiconductor layer, and is generated in the semiconductor layer by the incidence of light. The charge is collected by the electrode layer, and electric power is supplied from the electrode layer to the storage battery.

The dial 10 includes an absorption layer 11 and a light color layer 12 provided on the visible surface of the absorption layer 11. As shown in FIG. 2, in the first embodiment, the area where the light color layer 12 is provided corresponds to the light color portion W, and the area where the light color layer 12 is not provided corresponds to the dark color portion BK. That is, the user recognizes the area of the dial 10 where the light color layer 12 is provided as white, and the area of the dial 10 where the light color layer 12 is not provided and where the absorbing layer 11 is exposed as black. Become. Details of the reason why the user recognizes the color in this way will be described below.

The light-colored layer 12 may be, for example, a layer formed of a transparent resin containing a white pigment. Part of the light incident on the light-colored layer 12 is scattered at the interface between the transparent resin and the pigment, and the scattered light causes the user to see the light-colored layer 12 on which the light-colored layer 12 is provided on the visible surface of the dial 10. The part W will be recognized as white. It should be noted that another part of the light incident on the light-colored layer 12 is transmitted through the light-colored layer 12 and is incident on the absorption layer 11.

The higher the proportion of the pigment contained in the light-colored layer 12, the higher the light reflectance, and the user recognizes darker white as the color of the dial 10, while the amount of light incident on the solar cell 30 increases. Will decrease. As the proportion of the pigment included in the light-colored layer 12 decreases, the light reflectance decreases, the amount of light incident on the solar cell 30 increases, and the amount of power generation improves, while the user changes the color of the dial 10. A pale white will be recognized.

From the viewpoint of design, the dial plate 10 is required to have a darker white visual surface, but is also required to maintain the amount of power generated by the solar cell 30. Therefore, in the first embodiment, by adopting a configuration of transmitting the light incident on the dark color portion BK of the dial 10 in which the hour character 50, the display portion 60 and the like are provided, the solar cell 30 of the solar cell 30 is provided. It was decided to contribute to power generation. That is, a light-transmissive substrate was used as the absorbing layer 11 that constitutes the dark color portion BK of the dial plate 10.

In the first embodiment, the light incident on the dark color portion BK where the hour character 50 and the like are provided can contribute to the power generation of the solar cell 30, and the light color portion W is dark white. Also, the amount of power generation in the solar cell 30 can be maintained.

In the dial plate 10 of the first embodiment, the dark color portion BK has a higher light transmittance than the light color portion W. Since the dark color portion BK is composed of the absorption layer 11, the light color portion W has a laminated structure of the absorption layer 11 and the light color layer 12, and thus the light color portion W is less likely to transmit light. is there.

Here, in the first embodiment, the solar cell 30 having the property of easily absorbing the blue light component B and the green light component G of the visible light and hardly absorbing the red light component G was used. .. That is, in the solar cell 30, the blue light component B and the green light component G are likely to contribute to power generation, and the red light component R is less likely to contribute to power generation. Specifically, as the solar cell 30, a solar cell including a semiconductor layer such as amorphous silicon was used.

The red light component R not absorbed by the solar cell 30 will be reflected on the upper surface of the solar cell 30. When the red light component R is reflected on the upper surface of the solar cell 30, reddish light may leak in the light-transmitting dark portion BK and the aesthetics of the dial 10 may deteriorate. is there.

Therefore, in the first embodiment, as the absorption layer 11, a substrate having a property of easily transmitting the blue light component B and the green light component R and easily absorbing the red light component R is adopted. Specifically, in the first embodiment, as the absorbing layer 11, a substrate including a transparent substrate 111 and a color filter 112 attached on the transparent substrate 111 is adopted.

The color filter 112 absorbs the red light component R with a higher light absorptance than the blue light component B and the green light component G. That is, the color filter 112 has a property of easily transmitting the blue light component B and the green light component G and easily absorbing the red light component R. The transparent substrate 111 is preferably a substrate made of transparent resin, for example.

As shown in FIG. 2, of the light incident on the absorption layer 11, the blue light component B and the green light component G are easily transmitted through the absorption layer 11, and the red light component R is absorbed by the color filter 112. Cheap. As described above, in the light incident on the dark portion BK of the dial 10, the blue light component B and the green light component G, which are easily absorbed by the solar cell 30, easily reach the solar cell 30, and the solar cell 30 Since the red light component R that is easily reflected by 30 does not easily reach the solar cell 30, the amount of light reflected on the upper surface of the solar cell 30 is small.

When the light is reflected on the surface of the solar cell 30, the user visually recognizes the color of the reflected light or the color of the solar cell 30 itself, but according to the configuration of the first embodiment, the upper surface of the solar cell 30. There is little or no light reflected at. Therefore, the user will recognize the dark color portion BK as black.

Here, an example of the absorption layer 11 of the first embodiment will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram showing a haze value of a color filter and evaluation of whether or not the absorption layer including the color filter can be adopted in the wristwatch according to the first embodiment. FIG. 4 is a diagram showing the light transmittance for each wavelength in the color filter included in the absorption layer of the first embodiment.

In the first embodiment, a substrate having a color filter 112 having a small haze value is used as the absorption layer 11. The haze value is the ratio of diffused light (reflected light) to transmitted light when visible light is irradiated. That is, the larger the haze value is, the less light is transmitted, and the smaller the haze value is, the more light is transmitted. Further, when the haze value is large, it is difficult for light to pass therethrough, and thus the color of the color filter 112 itself is easily visible. On the other hand, when the haze value is small, the color of the color filter 112 itself is hard to be visually recognized because the light is easily transmitted. In the configuration of the first embodiment, when the haze value is large, the area where the color filter 112 is provided is visually recognized as blue green, and when the haze value is small, the area where the color filter 112 is provided is visually recognized as black. Will be done. In addition, the smaller the haze value, the larger the amount of light that passes through the color filter 112, and the more the power generation amount of the solar cell 30 increases. As described above, in the first embodiment, it can be said that the color filter 112 included in the absorption layer 11 preferably has a small haze value.

In FIG. 3, the haze value of the color filter 112 that can be adopted in the first embodiment is indicated by “◯”, and the haze value of the color filter 112 that cannot be adopted is indicated by “x”. Specifically, as shown in FIG. 3, in the first embodiment, if the haze value is 0 or more and 3 or less, it can be adopted, and if the haze value is higher than that, it is not adopted. And The haze value was measured with a surface reflection analyzer RA-532H (manufactured by Canon Inc.).

FIG. 4 shows an example of light transmittance characteristics for light in the visible light region in the color filter 112 adopted in the first embodiment. Specifically, in the first embodiment, LEE Filters 172 LAGOON BLUE (manufactured by LEE Filters) is used as the color filter 112. In addition, the measurement of the light transmittance was performed using an ultraviolet-visible spectrophotometer UV-1700 (manufactured by Shimadzu Science Co., Ltd.).

As shown in FIG. 4, in the color filter 112 used in the first embodiment, the light transmittance Tb of the blue light component B (wavelength: about 435.8 nm) is about 49.5%, and the green light component Tb is about 49.5%. The light transmittance Tg of the light component G (wavelength: about 546.1 nm) was about 24%, and the light transmittance Tr of the red light component R (wavelength: about 700 nm) was about 2.6%. As described above, the color filter 112 has a low light transmittance of the red light component R. That is, the light absorption rate of the red light component R is high.

However, it is not limited to the color filter having the above characteristics, and the light transmittance for the light component of each color may satisfy, for example, (Tb+Tg)/2>Tr. That is, the average value of the light transmittance Tb of the blue light component B and the light transmittance Tg of the green light component G may be larger than the light transmittance Tr of the red light component R. As described above, by using the absorption layer 11 including the color filter 112 that easily transmits the blue light component B and the green light component G and hardly transmits the red light component R, and easily absorbs the red light component R, the power generation of the solar cell 30 is performed. It is possible to represent black in the dark color portion BK while maintaining the amount.

Although the color filter 112 is provided as the absorption layer 11 in the first embodiment, this is an example, and the absorption layer 11 has a small haze value and has a blue light component B and a green light component G. Any material can be used as long as it absorbs the red light component R with a light absorption rate higher than the light absorption rate with respect to. For example, it may be formed by mixing a transparent resin with a pigment or dye.

In the above description, the haze value of the color filter 112 is 0 to 3, and the light transmittance of the color filter 112 is (Tb+Tg)/2>Tr. It may be 0 to 3, and the light transmittance of the absorption layer 11 may satisfy (Tb+Tg)/2>Tr.

In the first embodiment described above, since the dark color portion BK of the dial 10 is configured to transmit light, the power generation efficiency of the solar cell 30 can be improved. As described above, since the light incident on the dark color portion BK can be contributed to the power generation, the power generation amount of the solar cell 30 can be maintained even when the light transmittance in the light color portion W is reduced. it can. That is, the white color of the light color portion W can be made darker, and the designability can be improved.

In addition, in the first embodiment, it is possible to recognize black in the dark color portion BK and to prevent reddish light from leaking out from the dark color portion BK. That is, it is possible to suppress deterioration of the aesthetics of the dial 10.

In addition, in the first embodiment, as shown in FIG. 1, the solar cell 30 is arranged such that the area where the dividing line D of the solar cell 30 overlaps with the dark color portion BK is small in a plan view. The dividing line D is a boundary between the plurality of cells when the solar cell 30 including the plurality of cells is viewed in a plan view, and is a region in which power is not generated even when light is incident. As a result, many parts of the power generation region that contributes to power generation after the solar cell 30 overlaps with the dark color portion BK that easily transmits light. Therefore, power can be generated more efficiently. FIG. 1 shows an example in which the division line D of the solar cell 30 does not overlap with the hour character 50 that is the dark color portion BK in a plan view. However, the present invention is not limited to this, and the solar cell 30 may be arranged such that the non-power generation region such as the dividing line D of the solar cell 30 does not overlap any of the dark color portions BK in a plan view. In this case, it becomes possible to generate power more efficiently.

It should be noted that the solar cell 30 shown in FIG. 1 has an example in which the planar shape is circular and a dividing line is provided so as to divide it into four, but the present invention is not limited to this. That is, for example, the solar cell 30 may have a rectangular planar shape, or may have an opening, a cutout, or the like as a non-power generation region.

A first modification of the first embodiment will be described with reference to FIG. FIG. 5 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the first modified example of the first embodiment.

In the first modified example, the antireflection film 40 is provided on the dark portion BK of the visible surface of the dial 10. In this way, by providing the antireflection film 40 on the dark portion BK of the visible surface of the dial 10, the reflection of light on the visible surface side of the dial 10 can be suppressed, and the gloss of the dial 10 can be suppressed. it can. That is, the appearance of the dial 10 can be matte. In particular, it is possible to produce a high-class feeling by making the black color of the dark color portion BK be matte. Further, an antireflection film 40 was also provided on the back side of the dial 10. Part of the light that has passed through the color filter 112 and the transparent substrate 111 and is incident on the solar cell 30 is reflected on the front surface of the solar cell 30 and is incident on the back surface side of the transparent substrate 111. When the light incident from the back surface side is reflected on the back surface of the transparent substrate 111 in this way, the color of the color filter 112 itself is visually recognized. Therefore, as shown in FIG. 5, by providing an antireflection film 40 on the back surface side of the dial plate 10, the reflection of light on the back surface of the transparent substrate 111 is suppressed and the blue-green color of the color filter 112 itself is visually recognized. Can be suppressed. As a result, the dark color portion BK can be visually recognized by the user as a darker black color.

The arrangement of the antireflection film 40 shown in FIG. 5 is an example, and the arrangement is not limited to this. For example, the antireflection film 40 may be provided on only one of the visible surface side and the back surface side of the dial 10. Further, the antireflection film 40 may be provided on the light color layer 12.

Next, a second modification of the first embodiment will be described with reference to FIG. FIG. 6 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the second modification of the first embodiment. In the second modified example, the same reference numerals are used for the configurations made of the same material as the configuration shown in FIG.

The dial 10 of this example includes a transparent substrate 111, a color filter 112 provided on the transparent substrate 111, and a light color layer 12 provided on the transparent substrate 111. An area of the dial 10 where the color filter 112 is provided corresponds to the dark color portion BK, and an area where the light color layer 12 is provided corresponds to the light color portion W.

In this example, since the color filter 112 is provided only in the dark color portion BK and not in the light color portion W, the light incident on the light color portion W is transmitted as compared with the configuration shown in FIG. It's easy to do. Therefore, the power generation of the solar cell 30 can be performed more efficiently. Further, since the color filter 112 is provided only in the dark color portion BK and not in the light color portion W, it is possible to reduce the material cost as compared with the configuration shown in FIG. Further, as compared with the configuration shown in FIG. 2, the unevenness between the dark color portion BK and the light color portion W on the visible surface side of the dial 10 can be reduced, and the aesthetics can be further improved.

A third modification of the first embodiment will be described with reference to FIGS. 7 and 8. FIG. 7 is a plan view of the dial of the wristwatch according to the third modification of the first embodiment as viewed from the viewing surface side. FIG. 8 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the third modified example of the first embodiment, and is a VIII-VIII cross-sectional view of FIG. 7.

In FIG. 2, the wristwatch 1 including the dial 10 as the visual recognition member has been described, but in this example, the wristwatch 1 further including the hour hand 22 as the visual recognition member in addition to the dial 10 as the visual recognition member will be described. ..

As shown in FIG. 7, in the third modification, the wristwatch 1 has a second hand 21, an hour hand 22, and a minute hand 23 which are hands for moving on the dial 10.

FIG. 8 shows a cross section of the wristwatch 1 according to the third modification taken along a cutting line including the hour hand 22. The dial 10 shown in FIG. 8 has the same configuration as the dial 10 shown in FIG. That is, the power generation of the solar cell 30 by the light directly incident on the dial plate 10 without passing through the pointer is performed in the same manner as the configuration shown in FIG. Further, in the hour hand 22 shown in FIG. 8, the same components as those of the dial 10 are designated by the same reference numerals.

As shown in FIG. 8, the hour hand 22 includes an absorption layer 11 including a color filter and the like, and a light color layer 12 provided on the absorption layer 11. In the hour hand 22, the region where the light-colored layer 12 is provided corresponds to the light-colored portion W, and the region where the light-colored layer 12 is not provided and the absorption layer 11 is exposed on the visible surface side corresponds to the dark-colored portion BK. Further, in the hour hand 22 shown in FIG. 8, a dark color portion BK is provided on the edge of the hour hand 22 so as to surround the light color portion W.

At the hour hand 22, like the dial 10, the light incident on the light colored portion W is easily reflected, and the light incident on the dark colored portion BK is easily transmitted. Further, the red light component R is easily absorbed in the dark color portion BK.

7 and 8, the plan view shows that the hour hand 22 faces in a direction in which a part of the dark color portion BK of the hour hand 22 overlaps the dark color portion BK of the dial 10. Specifically, a part of the dark color portion BK of the hour hand 22 overlaps with “B” of the letters “ABCDEFG” indicating the brand name provided on the dial 10.

Hereinafter, with reference to FIG. 8, the power generation of the solar cell 30 by the light incident on each region of the hour hand 22 will be described.

First, the power generation of the solar cell 30 by the light incident on the dark color portion BK of the hour hand 22 overlapping the light color portion W of the dial 10 will be described. The blue light component B and the green light component G of the light incident on the dark color portion BK of the hour hand 22 easily pass through the hour hand 22. On the other hand, the red light component R of the light incident on the dark color portion BK of the hour hand 22 is easily absorbed by the absorption layer 11 of the hour hand 22 and is difficult to pass through. The blue light component B and the green light component G that have passed through the dark color portion BK of the hour hand 22 are incident on the light color portion W of the dial 10, part of which is reflected, and the other part is transmitted through the dial 10. To do. Then, the blue light component B and the green light component G that have passed through the dial 10 are incident on the solar cell 30 and contribute to power generation.

Next, power generation of the solar cell 30 by light incident on a region of the light colored portion W of the hour hand 22 that overlaps with the light colored portion W of the dial 10 will be described. Light incident on the light-colored portion W of the hour hand 22 is easily reflected. Further, a part of the light incident on the light colored portion W of the hour hand 22 passes through the light colored layer 12, but is incident on the absorption layer 11 of the hour hand 22, so that the red light component R is absorbed. Part of the blue light component B and the green light component G passes through the hour hand 22. The blue light component B and the green light component G that have passed through the hour hand 22 are incident on the light-colored portion W of the dial 10. A part of the light will further enter the solar cell 30 by further penetrating the dial plate 10, and will contribute to the power generation though it is slight.

Next, the power generation of the solar cell 30 by the light incident on the dark portion BK of the hour hand 22 overlapping the dark portion BK of the dial 10 will be described. The blue light component B and the green light component G of the light incident on the dark color portion BK of the hour hand 22 easily pass through the hour hand 22. On the other hand, the red light component R of the light incident on the dark color portion BK of the hour hand 22 is easily absorbed by the absorption layer 11 and hardly transmitted. The blue light component B and the green light component G that have passed through the hour hand 22 are incident on the dark color portion BK of the dial 10. Since the blue light component B and the green light component G incident on the dark portion BK of the dial 10 are easily transmitted, they are transmitted through the dial 10 and are incident on the solar cell 30. Then, the blue light component B and the green light component G that have passed through the dial 10 are incident on the solar cell 30 and contribute to power generation.

As described above, the light incident on the dark color portion BK of the hour hand 22 is absorbed by either the dark color portion BK or the solar cell 30, and therefore is not reflected and returned to the hour hand 22. Therefore, the user will recognize the dark color portion BK of the hour hand 22 as black.

Since a part of the blue light component B and the green light component G that have passed through the hour hand 22 is reflected by the light color layer 12 of the dial 10, the reflected light causes a blue-green color on the visible surface of the dial 10. A tinged color will occur. As a countermeasure against the occurrence of such reflected light of blue-green color, it is preferable to reduce the whiteness of the light color layer 12. That is, the light reflectance of the light-colored layer 12 may be lowered by reducing the proportion of the pigment or the like contained in the light-colored layer 12. As a result, the blue light component B and the green light component G are more likely to pass through the light color layer 12 of the dial 10, and the bluish green reflected light is less noticeable. However, from the viewpoint of design, the light reflectance of the dial 10 may be increased so that the reflected light of blue-green is noticeable.

In addition, after adopting the configuration shown in FIG. 8 for the hour hand 22, a member that easily absorbs the blue light component B and the green light component G may be provided on the back surface of the hour hand 22. Specifically, a member made of the same material as the solar cell 30 may be provided. As a result, the dark color portion BK of the hour hand 22 can be recognized by the user as black based on the same principle as that of the dark color portion BK of the dial 10, and the reflected light of blue-green on the dial 10 is generated. Can be suppressed. In this case, since the light incident on the hour hand 22 does not reach the solar cell 30 arranged on the back surface side of the dial 10, the configuration shown in FIG. 8 is more advantageous in terms of power generation efficiency. Is.

In the third modified example described above, the configuration in which the light incident on the hour hand 22 is transmitted to contribute to the power generation of the solar cell 30 is adopted. As a result, the power generation efficiency of the solar cell 30 can be further improved as compared with the case where a black substance that absorbs light is used as a guideline represented by black.

In the example shown in FIG. 8, the red light component R is absorbed by the absorption layer 11 of the hour hand 22 and the absorption layer 11 of the dial 10 before entering the solar cell 30, so that the red light component R is absorbed. Most of R is not incident on the solar cell 30. Therefore, aesthetic deterioration due to the solar cell 30 reflecting the red light component R does not occur.

In the third modified example, only the hour hand 22 of the hands has been described, but the second hand 21 and the minute hand 23 may have the same configuration. Further, the entire hands such as the hour hand 22 may be configured by the dark color portion BK. That is, the user may recognize the entire pointer as black. As a result, the amount of light that passes through the pointer increases, and the power generation efficiency of the solar cell 30 can be further improved.

Further, in the first embodiment, the dial 10 has the light color portion W and the dark color portion BK, and in the third modification, both the dial plate 10 and the pointer have the light color portion W and the dark color portion BK. Although an example is shown, the present invention is not limited to this, and a configuration having the light color portion W and the dark color portion BK may be applied only to the pointer. In this case, at least the dial 10 is transparent to light, and the solar cell 30 may be arranged on the back side of the dial 10.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 9 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the second embodiment. In the dial plate 210 of the second embodiment, a polarizing plate 211 with a retardation plate is adopted instead of the absorption layer 11 shown in the first embodiment.

The polarizing plate 211 with a retardation plate includes a polarizing plate 211a and a retardation plate 211b attached to the back surface of the polarizing plate 211a. The polarizing plate is a plate that transmits only the polarized light in a specific direction of the incident light. The retardation plate is a plate having a function of giving a phase difference to incident light. In the second embodiment, a substrate having a function of giving a phase difference of π/2 (λ/4) is adopted as the phase difference plate 211b.

As shown in FIG. 9, the dial 210 has a polarizing plate 211 with a retardation plate, and a light color layer 12 provided on the viewing surface side of the polarizing plate 211 with a retardation plate. In the dial plate 210, the region where the light color layer 12 is provided corresponds to the light color part W, and the region where the light color layer 12 is not provided and the polarizing plate 211 with the retardation plate is exposed corresponds to the dark color part BK.

As shown in FIG. 9, out of the incident light that has entered the polarizing plate 211 with the retardation plate, only the clockwise circularly polarized light is transmitted. This is because, as described above, the polarizing plate 211a transmits only the light polarized in a specific direction among the linearly polarized light components of the incident light, and the retardation plate 211b transmits the linearly polarized light component that has passed through the polarizing plate 211a. This is because the phase difference of π/2 (λ/4) is given to the light and the light is circularly polarized clockwise. Note that, of the linearly polarized light components, the light component polarized in the direction perpendicular to the specific direction is absorbed by the polarizing plate 211a.

Similar to the first embodiment, the blue light component B and the green light component G of the clockwise circularly polarized light transmitted through the polarizing plate 211 with the retardation plate are easily absorbed by the solar cell 30, and the It will contribute to power generation. On the other hand, of the right-handed circularly polarized light that has passed through the polarizing plate 211 with the retardation plate, the red light component R is hardly absorbed by the solar cell 30, and is reflected on the upper surface of the solar cell 30.

The right-handed circularly polarized light incident on the solar cell 30 is reflected by the upper surface of the solar cell 30 to become left-handed circularly polarized light. Then, the left-handed circularly polarized light component R of red light is incident on the back surface of the phase difference plate 211b. Since the retardation plate 211b gives a phase difference of π/2 to the incident light, the incident red light component R of the left-handed circularly polarized light becomes linearly polarized light which is polarized in a direction perpendicular to the specific direction. Since the polarizing plate 211a transmits only the light component polarized in the specific direction among the linearly polarized light components as described above, the red light component R that is the linearly polarized light polarized in the direction perpendicular to the specific direction is transmitted. Does not penetrate. That is, the red light component R incident from the back surface side of the polarizing plate 211a is absorbed by the polarizing plate 211a. In this way, the light reflected by the solar cell 30 does not leak to the outside of the dial plate 210, so that the user recognizes the dark color portion BK as black.

As described above, in the second embodiment, similarly to the first embodiment, it is possible to improve the power generation efficiency of the solar cell 30 and suppress deterioration of aesthetics.

In the second embodiment, as the polarizing plate 211 with a retardation plate, the one that absorbs light components in any wavelength band to the same extent and transmits them to the same extent has been described as an example. It is more preferable to adopt a configuration in which a phase difference is provided so that the light absorption rate of R becomes high.

In addition, in the second embodiment, an example in which the polarizing plate 211 with the retardation plate is provided in both the dark color portion BK and the light color portion W is shown, but the present invention is not limited to this, and the polarization plate with the retardation plate is not limited thereto. The plate 211 may be provided only in the dark color portion BK. In this case, it is advisable to adopt a configuration in which the polarizing plate with retardation plate 211 and the light color layer 12 are provided on the transparent substrate.

A wristwatch 201 according to a first modification of the second embodiment will be described with reference to FIGS. 10 and 11. FIG. 10 is a plan view schematically showing a wristwatch according to a first modified example of the second embodiment. 11 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the first modified example of the second embodiment, and is a cross-sectional view taken along the line XI-XI in FIG. 10.

As shown in FIGS. 10 and 11, the wristwatch 201 has at least a dial 210, a minute hand 223 as a pointer for moving the dial 210, and a solar cell 30 provided on the back side of the dial 210. .. Although the laminated structure of the minute hand 223 is omitted in FIG. 11, the dark color portion BK of the minute hand 223 includes at least the polarizing plate 211 with the retardation plate shown in FIG. The light-colored portion W of the minute hand 223 preferably includes at least the light-colored layer 12 shown in FIG. 9. Similarly, the dial plate 210 is also shown by omitting the laminated structure, but the dark color portion BK of the dial plate 210 includes at least the polarizing plate 211 with the retardation plate shown in FIG. The light color portion W of the dial plate 210 preferably includes at least the light color layer 12 shown in FIG. 9.

Further, in this example, the rotation locus of the light colored portion W of the minute hand 223 and the dark colored portion BK of the dial 210 overlap each other in plan view. Further, in plan view, the rotation locus of the dark color portion BK of the minute hand 223 and the light color portion W of the dial 210 overlap each other. That is, in a plan view, the dark color portion BK including the polarizing plate 211 with the retardation plate is provided on either the rotation trajectory of the minute hand 223 or the dial 210.

Specifically, the rotation center side of the minute hand 223 is the dark color portion BK, and the tip end side of the minute hand 223 is the light color portion W. Further, the central portion of the dial plate 210 is a light color portion W having a circular planar shape, and the periphery of the light color portion W is a ring-shaped dark color portion BK. Note that the dark color portion BK shown in FIG. 10 does not need to be the entire dark color portion BK, and may be an area in which hour characters and the like recognized as black are partially provided.

With such a configuration, as shown in FIG. 11, of the light incident on the minute hand 223, the blue light component B and the green light component G that are right-handed circularly polarized light are absorbed by the solar cell 30. Will be contributed to power generation. The red light component R, which is right-handed circularly polarized light, is reflected by the solar cell 30 to become left-handed circularly polarized light, and is absorbed by the dark color portion BK of the dial 210 or the dark color portion BK of the minute hand 223. Becomes As a result, the user recognizes the dark color portion BK of the minute hand 223 as black. Further, as described with reference to FIG. 9, the user also recognizes the dark portion BK of the dial 210 as black.

In this example, it is preferable that the light transmittance of the light color portion W of the dial plate 210 is high. That is, it is preferable that the haze value of the light colored portion W of the dial 210 is small. This is because if the light transmitted through the dark color portion BK of the minute hand 223 is scattered by the light color portion W of the dial 210, the user cannot recognize the dark color portion BK of the minute hand 223 as black.

In addition, in the example shown in FIGS. 10 and 11, both the dial 210 and the pointer have the light-colored portion and the dark-colored portion BK including the polarizing plate 211 with the retardation plate, but the invention is not limited thereto. Instead of this, only the pointer may have a light-colored portion W and a dark-colored portion BK including the polarizing plate 211 with a retardation plate. In this case, it is preferable that at least dial plate 210 transmits light and solar cell 30 is arranged on the back surface side of dial plate 210.

The configuration of this example is particularly suitable for the minute hand 223 having a relatively long length among the hands.

A wristwatch 201 according to a second modification of the second embodiment will be described with reference to FIGS. 12 and 13. FIG. 12 is a plan view schematically showing a wristwatch according to a second modified example of the second embodiment. 13 is a schematic cross-sectional view schematically showing a part of the cross section of the wristwatch according to the second modified example of the second embodiment, and is a cross-sectional view taken along the line XIII-XIII in FIG.

The second modification of the second embodiment relates to a pointer having a shorter length than the pointer described in the first modification of the second embodiment, that is, the hour hand 222, for example. In this example, as shown in FIGS. 12 and 13, the hour hand 222 is arranged so that the rotation trajectory of the hour hand 222 does not overlap the dark color portion BK of the dial 210. Further, the entire hour hand 222 is designated as a dark color portion BK. Other configurations are similar to those shown in FIGS. 10 and 11.

Also in this example, as shown in FIG. 13, the blue light component B and the green light component G are absorbed by the solar cell 30 and contribute to power generation, and the red light component R is on the upper surface of the solar cell 30. It is reflected and absorbed by the polarizing plate 211 with the retardation plate provided in the dark color portion BK. Therefore, the power generation efficiency of the solar cell 30 can be improved, and the user can recognize the dark portion BK of the hour hand 222 as black.

In each of the above-described embodiments and modifications, the solar cell wristwatch 1 has been described as an example, but the present invention is not limited to this, and at least a decorative plate or the like as a visual recognition member and the solar cell 30. Any power generation device including For example, it may be a power generator with a solar cell for a sensor or lighting equipment.

In each of the above-described embodiments and modifications, a solar cell having a property of easily absorbing the blue light component B and the green light component G has been described as an example, but the present invention is not limited to this, and a specific Any material may be used as long as it easily absorbs light components in the wavelength band and easily reflects light components in other wavelength bands. In this case, it is advisable to provide a color filter or the like having a high light absorptance with respect to light components in other wavelength bands in the dark color portion BK. Specifically, for example, as the solar cell 30, a dye-sensitized solar cell that positively absorbs a red light component may be used.

Although the embodiment of the present invention has been described above, the specific configuration shown in this embodiment is shown as an example, and the technical scope of the present invention is not intended to be limited thereto. Those skilled in the art may appropriately modify these disclosed embodiments, and it should be understood that the technical scope of the invention disclosed in this specification includes such modifications.

1,201 Wrist Watch, 10,210 Dial, 11 Absorption Layer, 111 Transparent Substrate, 112 Color Filter, 12 Light Color Layer, 21 Second Hand, 22,222 Hour Hand, 23,223 Minute Hand, 30 Solar Cell, 40 Antireflection Film, 50 Times, 60 Display, 211 Polarizing plate with retardation plate, 211a polarizing plate, 211b Retardation plate.

Claims (10)

One or a plurality of visible members which are visible to the user and include a light-colored portion and a dark-colored portion having a light transmittance higher than that of the light-colored portion;
A solar cell that generates power by the incidence of light that has passed through the visual recognition member,
Have
The solar cell is
Generation of power by incidence of a second light component of visible light on a second wavelength band different from the first wavelength band of generation of electricity by incidence of a first light component of first wavelength band on the visible light The amount of power generation is large,
The visual recognition member,
In the dark color portion, at least including an absorption layer that absorbs the first light component at a light absorption rate higher than the light absorption rate for the second light component,
Power generator with solar cells. The absorption layer includes a color filter,
The power generator with a solar cell according to claim 1. The haze value of the absorbing layer is 0 or more and 3 or less,
The power generator with a solar cell according to claim 1 or 2. One or a plurality of visible members which are visible to the user and include a light-colored portion and a dark-colored portion having a light transmittance higher than that of the light-colored portion;
A solar cell that generates power by the incidence of light that has passed through the visual recognition member,
Have
The solar cell is
Generation of power by incidence of a second light component of visible light on a second wavelength band different from the first wavelength band of generation of electricity by incidence of a first light component of first wavelength band on the visible light The amount of power generation is large,
The visual recognition member,
In the dark portion, a polarizing plate that transmits only the light component polarized in a specific direction and a position of π/2 with respect to the incident light component that is provided on the surface of the polarizing plate opposite to the visible surface. Including a phase difference plate that gives a phase difference,
Power generator with solar cells. The first wavelength band is a red wavelength band,
The second wavelength band includes at least a blue wavelength band or a green wavelength band,
The power generator with a solar cell according to any one of claims 1 to 4. An antireflection film is provided on the visual recognition surface of at least the dark color portion of the visual recognition member,
The power generator with a solar cell according to any one of claims 1 to 5. An antireflection film is provided on at least the dark-colored portion of the visual recognition member, which is opposite to the visual recognition surface.
The power generator with a solar cell according to any one of claims 1 to 6. A timepiece with a solar cell, which incorporates the power generation device with a solar cell according to any one of claims 1 to 7,
The visual recognition member is either one or both of a dial and a pointer for moving hands on the dial,
A solar-powered watch. The dark color portion includes at least an hour character provided on the dial.
The timepiece with a solar cell according to claim 8. The solar cell includes a power generation region where power is generated by incident light and a non-power generation region where power is not generated,
The solar cell is provided so that the non-power generation region does not overlap the time character in a plan view,
The timepiece with a solar cell according to claim 9.

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