JP7495339B2 - Solar Panel Clock - Google Patents

Description

The present invention relates to a clock with a solar panel.

Patent document 1 discloses a watch that is disposed in front of a solar cell and has a circular polarizing plate that transmits light. With this configuration, the circular polarizing plate can block light reflected from the surface of the solar cell. As a result, the solar cell can be prevented from being seen from the outside.

International Publication No. 2001/037350

Here, the circular polarizer can absorb light of a specific phase, but transmits light that is out of phase with that specific phase. In particular, light scattering can occur in the areas between multiple solar cells, causing the phase of the reflected light to shift. As a result, light reflected by the solar cells can pass through the circular polarizer and leak out to the outside. As a result, the areas between multiple solar cells can be seen from the outside, which can detract from the design of the watch.

The present invention was made in consideration of the above problems, and its purpose is to prevent the divided areas of the solar panel from being visible from the outside.

(1) The solar panel watch of the present invention has a dial including at least a retardation plate that imparts a phase difference to light passing through it and a polarizing plate that is provided above the retardation plate and transmits light components polarized in a specific direction; a solar panel that includes a plurality of solar cells arranged adjacent to each other via divided regions and generates electricity when light that has passed through the dial is incident on it; and a light absorbing member that is provided to overlap at least the divided regions in a plan view and has a higher light absorption property than the member that constitutes the power generation region of the solar cell.

(2) In the solar panel watch of (1), the solar panel includes a lower electrode layer, a semiconductor layer provided above the lower electrode layer, a light-transmitting upper electrode layer provided above the semiconductor layer, and an insulating layer adjacent to the division region and provided between the semiconductor layer and the upper electrode layer, and the light absorbing member is arranged so as to overlap the insulating layer in a plan view.

(3) In (2), the light absorbing member has a higher light absorption property than the insulating layer. A watch with a solar panel.

(4) A solar panel watch according to any one of (1) to (3), wherein the arithmetic mean roughness of the light absorbing member is 0.01 μm to 1 μm.

(5) A solar panel watch according to any one of (1) to (4), wherein the light absorbing member is made of a resin material and is filled in the divided area.

(6) A watch with a solar panel according to any one of (1) to (4), wherein the light absorbing member is provided on the surface of the solar panel.

(7) A solar panel watch according to any one of (1) to (4), in which the light absorbing member is provided on the underside of the dial.

(8) A watch with a solar panel according to any one of (1) to (7), wherein the light absorbing member includes a resin and a color pigment.

(9) A solar panel-equipped watch according to any one of (1) to (8), wherein the light absorbing member does not include a light scattering material.

(10) A watch with a solar panel according to any one of (1) to (9), wherein the light absorbing member is made of a material that scatters light less than the power generating area of the solar panel.

(11) A solar panel watch according to any one of (1) to (10), further comprising a sealing layer disposed above the upper electrode layer to protect the upper electrode layer, the sealing layer having a refractive index of 1.5 to 1.7.

(12) In (11), the refractive index of the upper electrode layer is 1.8 to 2.1.

(13) A solar panel watch according to (11) or (12), in which the portion of the upper surface of the sealing layer that corresponds to the divided area and the portion that corresponds to the power generation area of the solar panel are formed flush with each other.

(14) A watch with a solar panel according to any one of (1) to (13), wherein the solar panel includes a flexible film substrate.

(15) A watch with a solar panel according to any one of (1) to (13), wherein the solar panel includes a metal substrate.

According to aspects (1) to (15) of the present invention, it is possible to prevent the divided regions of the solar panel from being visible from the outside.

FIG. 1 is a plan view showing a solar panel watch according to an embodiment of the present invention. 2 is a cross-sectional view showing the cut surface of the timepiece taken along line II-II shown in FIG. 1. FIG. 1 is a plan view showing a solar panel of the present embodiment. 4 is a cross-sectional view showing a cross section of the solar panel and the dial taken along the line IV-IV shown in FIG. 3. 1 is a cross-sectional view showing a cut surface of a solar panel and a dial according to a first modified example of the present embodiment. FIG. 11 is a cross-sectional view showing a cut surface of a solar panel and a dial of a second modified example of the present embodiment. FIG. 13 is a cross-sectional view showing a cut surface of a solar panel and a dial of a third modified example of the present embodiment. FIG. 13 is a cross-sectional view showing a cut surface of a solar panel and a dial of a fourth modified example of the present embodiment. FIG. 13 is a cross-sectional view showing a cut surface of a solar panel and a dial of a fifth modified example of the present embodiment. FIG.

The following describes in detail an embodiment of the present invention (hereinafter, referred to as the present embodiment) with reference to the drawings.

[Outline of Solar Panel Clock 1]
FIG. 1 is a plan view showing a solar panel-equipped watch (hereinafter, simply referred to as a watch) 1 according to this embodiment. FIG. 1 shows a case 10 which is the exterior case (watch case) of the watch 1, a dial 3 arranged inside the case 10, and an hour hand 15, a minute hand 16, and a second hand 17 which indicate the time. Also, hour characters 18 are provided at predetermined positions on the dial 3. Also, band fixing parts 11 for fixing a band extend from the sides of the case 10 on the 12 o'clock and 6 o'clock sides. Also, a button 12 and a crown 13 for a user to perform various operations are arranged on the side of the case 10 on the 3 o'clock side. Note that the design of the watch shown in FIG. 1 is one example.

Figure 2 is a cross-sectional view showing a cut surface taken along the line II-II shown in Figure 1. Note that the crown 13 is omitted from Figure 2, and in order to make the placement of the hands easier to understand, the cross section is shown with the minute hand 16 pointing to the 9 o'clock direction, and the hour hand 15 and second hand 17 pointing to the 3 o'clock direction.

As shown in FIG. 2, the watch 1 has a crystal 30 made of a transparent material such as glass that covers the dial 3, and the crystal 30 is attached to the case 10. In addition, a back cover 19 is attached to the case 10 on the opposite side of the crystal 30.

In the rest of this specification, the front side of the paper in FIG. 1 (the upper side in FIG. 2) will be referred to as the upper side, and the back side of the paper in FIG. 1 (the lower side in FIG. 2) will be referred to as the lower side. In addition, the upper surface of each component will be referred to as the upper surface, and the lower surface will be referred to as the lower surface.

A solar panel 2 is disposed below the dial 3. The solar panel 2 generates electricity from the light that passes through the dial 3. For this reason, the dial 3 is made of a material that transmits light to a certain extent. As shown in FIG. 1, this embodiment shows an example in which a solar panel 2 with a roughly circular outer shape is disposed below the dial 3.

As shown in FIG. 2, the watch 1 further has a movement 40 provided below the solar panel 2. The movement 40 is a unit that includes a wheel train and motor for driving the hands, a clock circuit including a quartz crystal oscillator for measuring time, and a controller for controlling the entire watch 1, all assembled into a frame called a base plate. The movement 40 operates by obtaining power from a storage battery (not shown) attached to the movement 40. The storage battery supplies power to the movement 40 and stores the power generated by the solar panel 2, and is, for example, a button-type lithium secondary battery.

In this embodiment, the solar panel 2 is integrally provided with the movement 40. The movement 40 also has a pointer shaft that protrudes from the top surface of the dial 3, and the second hand 17, minute hand 16, and hour hand 15 are attached to their tips. The crystal 30 is fixed to the case 10 so as to cover these.

In this embodiment, a wristwatch is shown as the solar panel watch 1, but it is not limited to this and may be a pocket watch, etc.

[Solar Panel 2]
Next, the configuration of the solar panel will be described with reference to Figures 3 and 4. Figure 3 is a plan view showing the solar panel of this embodiment. Figure 4 is a cross-sectional view showing the cut surface of the solar panel and dial taken along the IV-IV cutting line shown in Figure 3.

The solar panel 2 includes a plurality of solar cells C arranged adjacent to each other with a division region D interposed therebetween. FIG. 3 shows a solar panel 2 including four solar cells C with a roughly sector-shaped planar shape. That is, the solar panel 2 is divided into four solar cells C via the division region D. The division region D is an area in which the lower electrode layer 22, semiconductor layer 23, upper electrode layer 24, etc. described below are not provided, and is an area located between the insulating layers 27 described below.

As shown in FIG. 4, the solar panel 2 includes a substrate 21, a lower electrode layer 22 provided on the substrate 21, a semiconductor layer 23 provided on the lower electrode layer 22, and an upper electrode layer 24 provided on the semiconductor layer 23.

Although not shown in the figure, the solar panel 2 may have wiring that electrically connects the lower electrode layer 22 and the upper electrode layer 24 to the storage battery, and wiring that connects the four solar cells C to each other in series or parallel.

The substrate 21 may be a flexible film substrate or may be a metal such as stainless steel (SUS).

The semiconductor layer 23 is a layer that has the function of converting incident light into electricity, and may be made of, for example, amorphous silicon. By using amorphous silicon, the efficiency of power generation by incident visible light can be improved. Therefore, it is possible to generate power efficiently even in places where there is no sunlight, such as indoors. However, this is not limited to this, and other semiconductors such as crystalline silicon may be used as the semiconductor layer 23.

The upper electrode layer 24 may be made of a transparent electrode having optical transparency. The upper electrode layer 24 may be made of, for example, ITO (Indium Tin Oxide), IZO (Indium Zinc Oxide), FTO (Fluorine-doped Tin Oxide), etc. The lower electrode layer 22 may be made of, for example, Al (Aluminum), Au (Gold), Ag (Silver), etc.

The solar panel 2 also includes a first sealing layer 25 provided on the upper electrode layer 24, and a second sealing layer 26 provided on the first sealing layer 25. The first sealing layer 25 and the second sealing layer 26 are layers that protect the upper electrode layer 24. The first sealing layer 25 and the second sealing layer 26 are preferably made of an insulating transparent resin or the like that has optical transparency. Note that the first sealing layer 25 and the second sealing layer 26 may be made of different materials or the same material as long as they have optical transparency.

In FIG. 4, a first sealing layer 25 is provided on the upper electrode layer 24 for each solar cell C, and a second sealing layer 26 is provided on the first sealing layer 25 over substantially the entire surface of the solar panel 2 so as to bridge each solar cell C that is spaced apart via a division region D.

The solar panel 2 further includes an insulating layer 27 adjacent to the division region D and disposed between the semiconductor layer 23 and the upper electrode layer 24.

In this embodiment, the insulating layer 27 is made of a material that does not have optical transparency. That is, in this embodiment, the area of the solar panel 2 where the insulating layer 27 is provided in a plan view (hereinafter referred to as the divided peripheral area P) and the divided area D constitute a part of the non-power generation area that does not contribute to power generation.

[Dial 3]
Next, the configuration of the dial 3 will be described with reference to Fig. 4. The dial 3 includes a retardation plate 31 and a polarizing plate 32 provided on the retardation plate 31. However, without being limited thereto, the dial 3 may further include a light-transmitting layer or substrate, such as a thickness adjustment layer for adjusting the thickness of the dial 3.

The retardation plate 31 is a plate that has the function of imparting a phase difference to incident light. In this embodiment, the retardation plate 31 is a plate that has the function of imparting a phase difference of π/2 (λ/4) to incident light that is incident from a direction perpendicular to the retardation plate 31.

The polarizing plate 32 is a linear polarizing plate that transmits only light polarized in a specific direction. In this embodiment, an example is described in which the polarizing plate 32 transmits only linearly polarized light that vibrates in a first axis direction perpendicular to the traveling direction, and absorbs linearly polarized light that vibrates in a second axis direction perpendicular to the traveling direction and the first axis direction.

The retardation plate 31 and the polarizing plate 32 are stacked on top of each other to function as a so-called circular polarizing plate.

[Incident light entering the power generation region]
Here, referring to Fig. 4, the incident light L1 that passes through the dial 3 and enters the power generation area of the solar panel 2 will be described. Note that in this embodiment, the area of the solar panel 2 other than the divided peripheral area P and the divided area D is considered to be the power generation area that contributes to power generation. Note that in Fig. 4, the traveling direction of the light is indicated by an arrow.

First, the incident light L1 is incident on the upper surface of the polarizing plate 32. Of the incident light L1 incident on the polarizing plate 32, linearly polarized light vibrating in the second axis direction is absorbed by the polarizing plate 32. On the other hand, of the incident light L1 incident on the polarizing plate 32, linearly polarized light vibrating in the first axis direction is transmitted through the polarizing plate 32. The linearly polarized light L11 vibrating in the first axis direction that has been transmitted through the polarizing plate 32 is incident on the upper surface of the retardation plate 31.

Linearly polarized light L11 incident on the upper surface of the retarder 31 passes through the retarder 31 and is given a phase difference of π/2 (λ/4). As a result, the light transmitted through the retarder 31 becomes circularly polarized light. In this embodiment, the light transmitted through the retarder 31 is right-handed circularly polarized light. Right-handed circularly polarized light L12 transmitted through the retarder 31 is incident on the solar panel 2.

The right-handed circularly polarized light L12 passes through the second sealing layer 26, the first sealing layer 25, and the upper electrode layer 24, and is incident on the semiconductor layer 23. A portion of the right-handed circularly polarized light L12 incident on the semiconductor layer 23 is absorbed by the solar panel 2 and contributes to power generation, and the other portion is reflected by the upper surface of the semiconductor layer 23. The light reflected by the semiconductor layer 23 becomes left-handed circularly polarized light L13.

The left-handed circularly polarized light L13 reflected by the semiconductor layer 23 passes through the upper electrode layer 24, the first sealing layer 25, and the second sealing layer 26, and is incident on the lower surface of the retardation plate 31. The left-handed circularly polarized light L13 incident on the retardation plate 31 passes through the retardation plate 31 and is given a phase difference of π/2 (λ/4), becoming linearly polarized light L14 that vibrates in the second axial direction.

Furthermore, linearly polarized light L14 that has passed through the phase difference plate 31 is incident on the lower surface of the polarizing plate 32. Because the polarizing plate 32 absorbs linearly polarized light that vibrates in the second axial direction, the linearly polarized light L14 that has passed through the phase difference plate 31 and is incident on the lower surface of the polarizing plate 32 is absorbed by the polarizing plate 32. In other words, the light reflected by the solar panel 2 does not leak out of the dial 3. Therefore, the user will see the power generation area of the solar panel 2 as black through the dial 3.

[Light incident on non-power generating region]
In the solar panel, it is conceivable to adopt a configuration in which an insulating layer (hereinafter referred to as the covering insulating layer) is formed so as to cover the divided region D and the divided peripheral region P. In that case, however, the light incident on the covering insulating layer is scattered, and the phase of the light is shifted. In other words, of the light reflected by the solar panel 2, the light reflected by the covering insulating layer does not have the desired phase. Specifically, the light reflected by the covering insulating layer becomes elliptically polarized light, not circularly polarized light. This causes a part of the reflected light reflected by the solar panel 2 to pass through the polarizing plate 32 and leak out to the outside. As a result, the covering insulating layer is visible from the outside through the dial 3, which can cause a problem of degraded design.

In addition, in a configuration in which an insulating layer 27 is provided adjacent to the division region D, a step is formed in the second sealing layer 26 depending on the thickness of the insulating layer 27. This results in unevenness on the surface of the second sealing layer 26. FIG. 4 shows an example in which a groove g is formed on the surface of the second sealing layer 26 in the division region D. Since the upper surface (top layer) of the solar panel 2 in the division region D is not flat, the light reflection performance in the division region D differs from that of the power generation region. Therefore, the reflected light in the division region D passes through the dial 3 and leaks out to the outside. As a result, the covering insulating layer is visible from the outside through the dial 3, which can cause a problem of reduced design.

Therefore, in this embodiment, a light absorbing material 28 is used as a covering insulating layer to prevent light reflected by the solar panel 2 from leaking to the outside.

The light absorbing member 28 is preferably made of a resin containing a black pigment that has low light scattering properties and high light absorption properties, particularly for visible light. Visible light is defined as light with a wavelength of approximately 400 nm to 800 nm.

Figure 4 shows an example in which the light absorbing member 28 is provided on the upper electrode layer 24 so as to overlap the divided peripheral region P in a plan view, and also fills the divided region D. That is, in this embodiment, as shown in Figure 4, an example is shown in which the covering region A (the region in which the light absorbing member 28 is provided) overlaps at least the divided region D and the divided peripheral region P in a plan view. In addition, the light absorbing member 28 may be formed to extend along the direction in which the divided peripheral region P and the divided region D extend. That is, in this embodiment, the light absorbing member 28 may be formed in a linear shape so as to follow the shapes of the divided peripheral region P and the divided region D shown in Figure 3.

With reference to FIG. 4, the incident light L2 incident on the coated area A will be described. The incident light L2 is incident on the polarizing plate 32. Of the incident light L2 incident on the polarizing plate 32, linearly polarized light vibrating in the second axis direction is absorbed by the polarizing plate 32. On the other hand, of the incident light L2 incident on the polarizing plate 32, linearly polarized light vibrating in the first axis direction is transmitted through the polarizing plate 32. The linearly polarized light L21 vibrating in the first axis direction that has been transmitted through the polarizing plate 32 is incident on the upper surface of the retardation plate 31.

Linearly polarized light L21 incident on the upper surface of the retarder 31 passes through the retarder 31 and is given a phase difference of π/2 (λ/4). As a result, the light transmitted through the retarder 31 becomes circularly polarized light. In this embodiment, the light transmitted through the retarder 31 is right-handed circularly polarized light. Right-handed circularly polarized light L22 transmitted through the retarder 31 is incident on the solar panel 2.

The right-handed circularly polarized light L22 passes through the second sealing layer 26 and enters the light absorbing member 28. As a result, the right-handed circularly polarized light L22 is absorbed by the light absorbing member 28. Therefore, the right-handed circularly polarized light L22 is prevented from being reflected by the semiconductor layer 23, as was the case with the right-handed circularly polarized light L12 described above. In other words, the light incident on the covered area A is prevented from being reflected by the solar panel 2 and leaking out to the outside.

This prevents the divided area D from being visible from the outside through the dial 3. As a result, the design of the watch 1 is prevented from being degraded. Furthermore, because the divided area D is an area that does not contribute to power generation, the amount of power generation in the solar panel 2 is not reduced even if the light absorbing member 28 is provided.

In this embodiment, the reflected light reflected by the semiconductor layer 23 has been described with reference to FIG. 4, but in reality, part of the light incident on the solar panel 2 is also reflected by the upper electrode layer 24, the first sealing layer 25, and the second sealing layer 26. In order to prevent the light reflected by the upper electrode layer 24 from scattering, it is preferable that the refractive indexes of the upper electrode layer 24 and the first sealing layer 25 are close to each other. In addition, it is preferable that the first sealing layer 25 is made of a resin that does not have birefringence. Specifically, for example, the refractive index of the first sealing layer 25 is preferably 1.5 to 1.7. In addition, it is preferable that the refractive index of the upper electrode layer 24 is 1.8 to 2.1.

In addition, in this embodiment, as described above, the light absorbing member 28 is configured to contain a pigment that has high light absorption properties for visible light. This makes it possible to prevent visible light reflected by the solar panel 2 from leaking out to the outside when the solar panel 2 is used to generate power using indoor lighting. In other words, when the watch 1 is used indoors, it is possible to prevent the divided areas D, etc. of the solar panel 2 from being visible from the outside through the dial 3.

However, this is not a limitation, and the light absorbing member 28 should be made of a material that is at least more light absorbing than the material that constitutes the power generation area of the solar panel 2. In other words, the light absorbing member 28 should be made of a material that is less likely to cause light scattering than the material that constitutes the power generation area of the solar panel 2. Specifically, the arithmetic mean roughness Ra of the upper surface of the light absorbing member 28 should be 0.01 μm to 1 μm. The light absorbing member 28 should not contain a light scattering material. The arithmetic mean roughness represents the average distance from a reference line, with the average value of the unevenness of the surface being set as the reference line. The smaller the arithmetic mean roughness, the less unevenness there is and the smoother the plane is.

In this embodiment, the material of the insulating layer 27 is the same as that of the light absorbing member 28. That is, the insulating layer 27 is made of a material that is more light absorbing than the material that constitutes the power generation region of the solar panel 2, and its arithmetic mean roughness is 0.01 μm to 1 μm. However, this is not limited to this, and the insulating layer 27 may be made of a material that is more light transparent than the light absorbing member 28. In other words, the insulating layer 27 may be made of a material that is less light absorbing than the light absorbing member 28. If the insulating layer 27 has a lower light absorbing property than the light absorbing member 28, there is a risk that the light incident on the divided peripheral region P is reflected by the insulating layer 27, and the reflected light leaks out to the outside, causing the insulating layer 27 to be visible. However, in this embodiment, a configuration is adopted in which the light absorbing member 28 is provided so as to overlap the insulating layer 27 in a plan view, so that the light is absorbed by the light absorbing member 28 before reaching the insulating layer 27. Therefore, the divided peripheral region P is prevented from being visible from the outside through the dial 3.

The multiple solar cells C may be generated by, for example, removing a portion of a single, substantially circular cell by irradiating it with laser light or the like. In other words, the division region D may be formed by irradiating it with laser light or the like, and multiple solar cells C may be formed. Alternatively, the multiple solar cells C may be formed on the substrate 21 by arranging multiple independent, substantially sector-shaped cells that have been generated in advance so that they are spaced apart from each other via the division region D.

[First Modification]
Next, a first modified example of this embodiment will be described with reference to Fig. 5. Fig. 5 is a cross-sectional view showing a cut surface of a solar panel and a dial of a first modified example of this embodiment. Fig. 5 shows a cut surface cut along the same cut line as Fig. 4. That is, it shows a cut surface cut along a cut line passing through the divided peripheral area P and divided area D of the solar panel of the first modified example. Note that the same reference numerals are used for components having the same functions as the components described with reference to Figs. 1 to 4, and detailed descriptions thereof will be omitted.

In the first modified example, a configuration is adopted in which the surface of the solar panel 2 in the division region D is flat. Specifically, the light absorbing member 28 is provided on the upper electrode layer 24, and the upper surface of the first sealing layer 25 is provided so as to be flush with the upper surface of the light absorbing member 28. Then, the second sealing layer 26 is provided on the first sealing layer 25 and the light absorbing member 28. As a result, the upper surface of the second sealing layer 26 is flat. In other words, the portion of the upper surface of the second sealing layer 26 that corresponds to the division region D and the portion that corresponds to the power generation region are formed to be flush with each other.

In the first modified example, the surface of the solar panel 2, particularly the surface of the divided area D, is smooth, so light scattering is less likely to occur in the divided area D. This further reduces the possibility that light reflected by the solar panel 2 will leak out to the outside.

[Second Modification]
Next, a second modified example of this embodiment will be described with reference to Fig. 6. Fig. 6 is a cross-sectional view showing a cut surface of a solar panel and a dial of the second modified example of this embodiment. Fig. 6 shows a cut surface cut along the same cut line as Figs. 4 and 5. That is, a cut surface cut along a cut line passing through the divided peripheral area P and divided area D of the solar panel of the second modified example is shown. Note that the same reference numerals are used for components having the same functions as the components described with reference to Figs. 1 to 4, and detailed descriptions thereof will be omitted.

In the second modified example, as shown in FIG. 6, a light absorbing member 28 is provided on the second sealing layer 26. The light absorbing member 28 is provided so as to overlap the divided peripheral region P and divided region D in a plan view. Therefore, as shown in FIG. 6, right-handed circularly polarized light L22 that is transmitted through the dial 3 out of the incident light L2 to the divided peripheral region P and divided region D is absorbed by the light absorbing member 28. This makes it possible to prevent the light that is incident on the divided peripheral region P and divided region D from being reflected by the solar panel 2 and leaking out through the dial 3 to the outside.

[Third Modification]
Next, a third modified example of this embodiment will be described with reference to Fig. 7. Fig. 7 is a cross-sectional view showing a cut surface of a solar panel and a dial of a third modified example of this embodiment. Fig. 7 shows a cut surface cut along the same cut lines as Figs. 4, 5, and 6. That is, it shows a cut surface cut along a cut line passing through the divided peripheral area P and divided area D of the solar panel of the third modified example. Note that the same reference numerals are used for components having the same functions as those described with reference to Figs. 1 to 4, and detailed descriptions thereof will be omitted.

In the third modified example, as shown in FIG. 7, a light absorbing member 38 is provided on the underside of the dial 3. Specifically, the light absorbing member 38 is provided on the underside of the retardation plate 31 of the dial 3, and is arranged to overlap the divided peripheral region P and divided region D in a plan view. Therefore, as shown in FIG. 7, incident light L2 incident on the region of the dial 3 that overlaps with the divided peripheral region P and divided region D is absorbed by the light absorbing member 38 before reaching the solar panel 2. This makes it possible to suppress light reflection at the divided peripheral region P and divided region D of the solar panel 2. As a result, it is possible to suppress light leaking to the outside through the dial 3.

[Fourth Modification]
Next, a fourth modified example of this embodiment will be described with reference to Fig. 8. Fig. 8 is a cross-sectional view showing a cut surface of a solar panel and a dial of the fourth modified example of this embodiment. Fig. 8 shows a cut surface cut along the same cut line as Fig. 4 and the like. That is, a cut surface cut along a cut line passing through the divided peripheral area P and divided area D of the solar panel of the fourth modified example is shown. Note that the same reference numerals are used for components having the same functions as the components described with reference to Figs. 1 to 4, and detailed descriptions thereof will be omitted.

In the fourth modified example, as shown in FIG. 8, a light absorbing member 28 is provided on the second sealing layer 26 only in the area that overlaps with the division region D in a planar view. That is, in the fourth modified example, the division region D and the covering region A are areas that coincide in a planar view. As shown in FIG. 8, of the light L2 incident on the division region D (covering region A), the right-handed circularly polarized light L22 that has passed through the dial 3 is absorbed by the light absorbing member 28. This makes it possible to prevent the light incident on the division region D (covering region A) from being reflected by the solar panel 2 and leaking out through the dial 3.

In the fourth modified example, the insulating layer 27 may be made of the same material as the light absorbing member 28. In other words, the light incident on the divided peripheral region P may be absorbed by the insulating layer 27. This prevents the light incident on the divided peripheral region P from being reflected by the solar panel 2 and leaking out through the dial 3.

In the fourth modified example, the amount of light absorbing material 28 is minimized, so that material costs can be reduced. Also, in the fourth modified example, the non-power generating area can be limited to the divided area D and the divided peripheral area P, so that the power generating area can be made larger than in the configuration shown in FIG. 4. As a result, the power generating effect can be maximized. Note that FIG. 8 shows an example in which the divided area D and the covered area A coincide in a plan view, but this is not limited thereto, and the covered area A may be larger than the divided area D. In this case, it is preferable that the covered area A is arranged so as to overlap a part of the divided peripheral area P rather than overlapping the entire divided peripheral area P in a plan view.

[Fifth Modification]
Next, a fifth modified example of this embodiment will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view showing a cut surface of a solar panel and a dial of the fifth modified example of this embodiment. Fig. 9 shows a cut surface cut along the same cut line as Fig. 4 and the like. That is, it shows a cut surface cut along a cut line passing through the divided peripheral area P and divided area D of the solar panel of the fifth modified example. Note that the same reference numerals are used for components having the same functions as the components described with reference to Figs. 1 to 4, and detailed descriptions thereof will be omitted.

In the fifth modified example, as shown in FIG. 9, a light absorbing member 38 is provided only on the underside of the dial 3 in an area that overlaps with the divided area D in a plan view. That is, in the fifth modified example, the divided area D and the covered area A are areas that coincide in a plan view. As shown in FIG. 9, incident light L2 that is incident on the area of the dial 3 that overlaps with the divided area D (covered area A) is absorbed by the light absorbing member 38 before reaching the solar panel 2. This prevents light that is incident on the divided area D (covered area A) from being reflected by the solar panel 2 and leaking out through the dial 3 to the outside.

In addition, in the fifth modified example, the insulating layer 27 may be made of the same material as the light absorbing member 38. In other words, the light incident on the divided peripheral region P may be absorbed by the insulating layer 27. This prevents the light incident on the divided peripheral region P from being reflected by the solar panel 2 and leaking out through the dial 3 to the outside.

In the fifth modified example, as in the fourth modified example, the amount of light absorbing material 38 is minimized, so that material costs can be reduced. Furthermore, in the fifth modified example, the non-power generating area can be limited to the divided area D and the divided peripheral area P, so that the power generating area can be made larger than the configuration shown in FIG. 7. As a result, the power generating effect can be maximized. Note that FIG. 9 shows an example in which the divided area D and the covered area A coincide in a plan view, but this is not limited thereto, and the covered area A may be larger than the divided area D. In this case, it is preferable that the covered area A is arranged so as to overlap a part of the divided peripheral area P rather than the entire divided peripheral area P in a plan view.

1 watch with solar panel, 10 body, 11 band fixing part, 12 button, 13 crown, 15 hour hand, 16 minute hand, 17 second hand, 18 hour marker, 19 back cover, 2 solar panel, 21 substrate, 22 lower electrode layer, 23 semiconductor layer, 24 upper electrode layer, 25 first sealing layer, 26 second sealing layer, 27 insulating layer, 29 light absorbing material, 3 dial, 31 retardation plate, 32 polarizing plate, 38 light absorbing material, 30 crystal, 40 movement, C solar cell, D divided area, P divided peripheral area, L1, L2 incident light.

Claims (15)

a dial including a retardation plate that imparts a phase difference to light passing therethrough, and a polarizing plate that is disposed above the retardation plate and transmits a light component polarized in a specific direction;
a solar panel including a plurality of solar cells arranged adjacent to each other with divided regions interposed therebetween, the solar panel generating electricity when light that has passed through the dial is incident thereon;
a light absorbing member that is arranged to overlap the division region in a plan view and has a higher light absorption property than a member that constitutes the power generation region of the solar cell;
having
The light that is transmitted through the polarizing plate and the retardation plate and is incident on the solar panel is reflected by the upper surface of the solar panel, and the reflected light is transmitted through the retardation plate and absorbed by the polarizing plate,
The light absorbing member is formed along a direction in which the divided regions extend in a plan view.
Solar panel clock. the solar panel includes a lower electrode layer, a semiconductor layer provided above the lower electrode layer, a light-transmitting upper electrode layer provided above the semiconductor layer, and an insulating layer adjacent to the division region and provided between the semiconductor layer and the upper electrode layer;
The light absorbing member is provided so as to overlap the insulating layer in a plan view.
A clock with a solar panel according to claim 1. a sealing layer provided above the upper electrode layer and protecting the upper electrode layer;
The refractive index of the sealing layer is 1.5 to 1.7.
A clock with a solar panel according to claim 2. The refractive index of the upper electrode layer is 1.8 to 2.1.
A clock with a solar panel according to claim 3. A portion of the upper surface of the sealing layer corresponding to the division region and a portion of the upper surface of the sealing layer corresponding to the power generation region of the solar panel are formed to be flush with each other.
5. A clock with a solar panel according to claim 3 or 4. The light absorbing member has a higher light absorbing property than the insulating layer.
A clock with a solar panel according to any one of claims 2 to 5. The arithmetic mean roughness of the light absorbing member is 0.01 μm to 1 μm.
A clock with a solar panel according to any one of claims 1 to 6. The light absorbing member is made of a resin material and is filled in the divided region.
A clock with a solar panel according to any one of claims 1 to 7. The light absorbing member is provided on a surface of the solar panel.
A clock with a solar panel according to any one of claims 1 to 7. The light absorbing member is provided on the lower surface of the dial.
A clock with a solar panel according to any one of claims 1 to 7. The light absorbing member includes a resin and a color pigment.
A clock with a solar panel according to any one of claims 1 to 10. The light absorbing member does not contain a light scattering material.
A clock with a solar panel according to any one of claims 1 to 11. The light absorbing member is made of a material that scatters light less than the power generating region of the solar panel.
A clock with a solar panel according to any one of claims 1 to 12. The solar panel includes a flexible film substrate.
A clock with a solar panel according to any one of claims 1 to 13. The solar panel includes a metallic substrate.
A clock with a solar panel according to any one of claims 1 to 13.

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