JP2020016573A - Watch having solar battery - Google Patents

Abstract

To provide a watch 1 having a solar battery capable of securing a power generation amount without spoiling the beauty.SOLUTION: A watch 1 having a solar battery includes: a number plate 14 having a region a of a high optical transparency and a region c of an optical transparency lower than that of the region a; and a solar battery 30 having at least power generation region E for generating power by incidence of light having passed through the number plate 14. The region c is disposed, in the plane view, so as to overlap with a non power generation region N that does not contribute to the power generation of at least the solar battery 30 and with a non arrangement region M having no solar battery 30. The region a is disposed, in the plane view, so as to overlap with at least power generation region E.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a timepiece with a solar cell.

  2. Description of the Related Art In a timepiece with a solar cell, a light-transmitting dial is used to allow light to enter the solar cell. The solar cell has a unique dark purple color, and if the solar cell can be seen through the dial, the appearance may be impaired. Therefore, for example, in the dial disclosed in Patent Literature 1, the unevenness formed by a mountain portion and a valley portion having a substantially right-angle cross section is formed on the lower surface, so that the light is dispersed and diffused to form the sun. The device is designed to erase the color of the battery.

JP 2011-174948 A

  As disclosed in Patent Document 1, when unevenness is formed on the lower surface of the dial, the reflectance of light on the dial is increased, and the visibility of the internal structure of the timepiece provided below the dial is reduced. On the other hand, there is a possibility that the amount of power generation in the solar cell is reduced due to a decrease in light transmittance.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a timepiece with a solar cell capable of securing an amount of power generation without impairing aesthetic appearance.

  The invention disclosed in the present application has various aspects in order to solve the above-mentioned problems, and typical aspects of the aspects are outlined below.

  (1) A dial including a high-transmission region having high light transmission and a low-transmission region having lower light transmission than the high-transmission region, and a power-generating region for generating power by receiving light transmitted through the dial. A solar cell including at least, the low transmission region, in a plan view, at least overlap with a non-power generation region that does not contribute to power generation of the solar cell or a non-arranged region where the solar cell is not provided. A timepiece with a solar cell, wherein the timepiece is provided so that the high transmission area is provided so as to overlap at least the power generation area in a plan view.

  (2) In (1), the lower surface of the dial in the high transmission area and the low transmission area has a valley recessed toward the upper surface of the dial and the lower surface adjacent to the valley. Including at least the convexity and the convexity of the mountain portion projecting to the side, at least the cross-sectional shape of the bottom of the valley is a rounded shape, the cross-sectional shape of the bottom in the high transmission region, the low transmission A timepiece with a solar cell, wherein the timepiece has a rounded shape larger than a cross-sectional shape of the bottom portion in a region.

  (3) In (2), the cross-sectional shape of the top of the ridge portion is rounded, and the cross-sectional shape of the top in the high transmission region is better than the cross-sectional shape of the top in the low transmission region. A watch with a solar cell that is larger and more rounded.

  (4) The timepiece with a solar cell according to (2) or (3), wherein a radius of curvature at the bottom of the valley is larger than a radius of curvature at the top of the ridge.

  (5) In any one of the constitutions (1) to (4), the dial has a medium transmission region having a lower light transmission than the high transmission region and a higher light transmission than the low transmission region. The timepiece with a solar cell, wherein the middle transmission area is provided between the high transmission area and the low transmission area.

  (6) The timepiece with a solar cell according to (5), wherein in the middle transmission region, the light transmittance increases stepwise or continuously from the low transmission region side to the high transmission region side.

  (7) In (1), the lower surface of the dial in the high transmission region and the low transmission region has a valley recessed toward the upper surface of the dial and the lower surface adjacent to the valley. A timepiece with a solar cell, including irregularities comprising a mountain portion protruding to the side, and at least a bottom portion of the valley portion is flat in at least the high transmission region.

  (8) In (7), the dial has a middle transmission region having a lower light transmission than the high transmission region and a higher light transmission than the low transmission region. , Provided at least between the high transmission region and the low transmission region, the valley portion having a flat bottom surface, and from the low transmission region side toward the high transmission region in the middle transmission region. , The area of the flat surface of the bottom of the valley gradually increases in accordance with the following.

  (9) In (1), the lower surface of the dial in the high transmission area and the low transmission area has a valley recessed toward the upper surface of the dial and the lower surface adjacent to the valley. Including the unevenness consisting of a mountain portion projecting to the side, at least one of the cross-sectional shape of the bottom of the valley portion or the cross-sectional shape of the top of the mountain portion in the high transmission region is a rounded shape A timepiece with a solar cell, wherein at least one of a cross-sectional shape of a bottom portion of the valley portion and a cross-sectional shape of a top portion of the mountain ridge portion in the low transmission region is square.

  (10) The timepiece with a solar cell according to any one of (1) to (9), wherein a paint is applied to at least one of the high transmission region and the low transmission region on the lower surface of the dial.

  (11) The timepiece with a solar cell according to (1) or (2), wherein the high transmission region includes a surface having a sine curve in cross section.

  (12) The timepiece with a solar cell according to any one of (2) to (4), wherein the valley portion and the mountain portion are formed concentrically or spirally on the lower surface.

  (13) The timepiece with a solar cell according to any one of (1) to (12), wherein the dial is made of a polycarbonate resin or an acrylic resin.

  According to the aspects (1) to (13) of the present invention, it is possible to provide a timepiece with a solar cell capable of securing an amount of power generation without impairing aesthetic appearance.

It is a top view showing the electronic timepiece concerning this embodiment. It is sectional drawing in the AA cutting line of FIG. It is sectional drawing which shows the dial of this embodiment, and the outline | summary of a solar cell. It is the top view which looked at the dial of this embodiment from the lower surface side. It is a mimetic diagram explaining transmission of light in a valley part of unevenness formed in a dial of this embodiment. It is a top view showing the solar cell in this embodiment. It is a top view which shows the dial in this embodiment typically. FIG. 8 is a diagram illustrating a cross-sectional view taken along the line BB of FIG. 7 and a relationship between transmittance and reflectance. It is sectional drawing which shows the dial of the 1st modification of this embodiment, and the outline | summary of a solar cell. It is sectional drawing which shows the outline of the dial and solar cell of the 2nd modification of this embodiment.

  Hereinafter, embodiments of the present invention (hereinafter, referred to as the present embodiment) will be described in detail with reference to the drawings.

  FIG. 1 is a plan view showing a timepiece with a solar cell according to the present embodiment. FIG. 2 is a cross-sectional view taken along line AA of FIG. In FIG. 2, a crown 13 described later is not shown, and the minute hand 16 is oriented at 9 o'clock, and the hour hand 15 and the second hand 17 are moved at 3 o'clock for easy understanding of the placement of the hands. In the direction of.

  FIG. 1 shows a body 10 which is an exterior (watch case) of the timepiece 1 with a solar cell, a dial 14 arranged inside the body 10, an hour hand 15, a minute hand 16 and a second hand 17 which are hands indicating time. I have. Further, the hour dial 49 is provided on the dial 14 at a predetermined position. Further, a band fixing portion 11 for fixing the band extends from the side of the body 10 on the 12 o'clock side and the 6 o'clock side. A button 12 and a crown 13 for a user to perform various operations are arranged on the side of the body 10 on the 3 o'clock side.

  The design of the timepiece shown in FIG. 1 is an example. In addition to those shown here, for example, the body 10 may be formed in a square shape instead of a round shape, and the presence, absence, number, and arrangement of the buttons 12 and the crown 13 are arbitrary. Further, in the present embodiment, the three hands of the hour hand 15, the minute hand 16, and the second hand 17 are used. However, the present invention is not limited to this. It is also possible to add a radio signal reception state, a remaining battery level, a guideline for performing various displays, a date display, and the like.

  In the present specification, as the clock 1 with a solar battery, a satellite (GPS) such as a Global Positioning System (GPS) satellite receives a satellite signal including date and time information and transmits a satellite signal including the date and time information. 1 shows a satellite radio-controlled wristwatch having a function of correcting an internal time held inside a watch based on information related to the watch. However, the present invention is not limited to this, and may be a radio-controlled timepiece that receives a standard radio wave and corrects the internal time, or may be a clock that does not have such a time correction function.

  As shown in FIG. 2, the timepiece with a solar battery 1 has a windshield 32 formed of a transparent material such as glass so as to cover the dial 14, and the windshield 32 is attached to the body 10. On the opposite side of the windshield 32, a back cover 36 is attached to the body 10. In the present specification, the side of the watch where the windshield 32 is arranged (the front side in FIG. 1) will be referred to as the upper side, and the side where the back cover 36 is arranged (the rear side in the plane of FIG. 1) will be referred to as the lower side.

  A solar cell 30 is arranged below the dial 14, and power is generated by light transmitted through the dial 14 and incident on the solar cell 30 from above. Therefore, the dial 14 is formed of a material that transmits light rays to some extent. For example, the dial 14 may be made of a polycarbonate resin or an acrylic resin. Further, the resin is not limited to these resins, and any transparent resin may be used. For example, a fluororesin or an ethylene-based resin may be used.

  In the present embodiment, as shown by the broken line in FIG. 1, the solar cell 30 has a substantially circular shape, and the direction from 10 o'clock to 2 o'clock is cut off in a fan shape. A patch antenna 20 for receiving a satellite signal is arranged in the cutout portion (the area where the solar cell 30 does not exist) below the dial 14. Thus, by arranging the patch antenna 20 so as not to overlap with the solar cell 30 in a plan view, it is possible to suppress the influence of the electrodes included in the solar cell 30 on the receiving sensitivity of the patch antenna 20.

  As shown in FIG. 2, the timepiece with a solar cell 1 further includes a transflective reflector 47 provided between the dial 14 and the solar cell 30, and a movement 38 provided below the solar cell 30. The movement 38 is such that a train wheel and a motor for driving hands, a clock circuit including a quartz oscillator for measuring time, a controller for controlling the entire solar cell clock 1, and the like are integrally assembled in a frame called a main plate. is there. The movement 38 operates by obtaining electric power from a storage battery attached to the movement 38. The storage battery supplies power to the movement 38 and, at the same time, stores the power generated by the solar cell 30, and is, for example, a button-type lithium secondary battery.

  In the present embodiment, the solar cell 30 is provided integrally with the movement 38. A pointer shaft is provided on the movement 38 so as to protrude from the upper surface of the dial 14, and a second hand 17, a minute hand 16, and an hour hand 15 are attached to the tip thereof. The windshield 32 is fixed to the body 10 so as to cover them.

  Next, the configuration of the dial 14 of the present embodiment will be described with reference to FIGS. FIG. 3 is a cross-sectional view showing an outline of the dial and the solar cell of the present embodiment. FIG. 4 is a plan view of the dial of the present embodiment viewed from the lower surface side.

  A semi-transmissive reflector 47 may be provided between the dial 14 and the solar cell 30, as shown in FIG. 2, in order to transmit and reflect the incident light appropriately. Therefore, the illustration of the semi-transmissive reflection plate 47 is omitted in FIG. In FIG. 3, hatching is omitted to avoid complicating the drawing. As shown in FIG. 3, the space between the lower surface of the dial 14 and the solar cell 30 is an air layer 24. Since the dial 14 and the air layer 24 have different refractive indexes, light is refracted or reflected at the interface between the lower surface of the dial 14 and the air layer 24.

  In the following description, as shown in FIG. 3, a region of the dial 14 that does not overlap with the solar cell 30 in plan view is a region c, and a region of the dial 14 that does not overlap with the solar cell 30 in plan view is a region that is not adjacent to the region c. The region a, a region adjacent to the region c in the region overlapping the solar cell 30 in plan view, is referred to as a region b. In the present embodiment, the region a is a high-transmission region having high light transmittance, the region c is a low-transmission region having lower light transmittance than the region a, and the region b is lower light transmission than the region a. A medium transmission region having a higher light transmittance than c.

  In the present embodiment, on the lower surface of the dial 14 in the region a, irregularities formed by a valley portion 141 depressed upward and a ridge portion 142 protruding downward adjacent to the valley portion 141 are provided. Is formed. The reason why the unevenness is formed on the lower surface of the dial 14 in this way is that light is reflected at the interface between the lower surface of the dial 14 and the air layer 24 so that the lower side of the dial 14 such as the solar cell 30 can be viewed from the outside. This is for the purpose of making the internal structure provided in the device inconspicuous. The height and pitch of the unevenness are preferably several tens μm to one hundred and several tens μm. In the present embodiment, the most concave portion of the lower surface of the dial 14 is referred to as a bottom portion, and the most protruding portion is referred to as a top portion.

  In the present embodiment, the valley portion 141 is a portion above the middle between the bottom portion 141a and the top portion 142a in the thickness direction of the dial 14, and the ridge portion 142 is formed in the thickness direction of the dial 14. It is defined as a portion below the middle between the bottom portion 141a and the top portion 142a. That is, in the present embodiment, the depth of the valley portion 141 and the height of the mountain ridge portion 142 in the thickness direction of the dial 14 are equal. The same applies to valleys and ridges in regions b and c described later.

  In the present embodiment, the lower surface of the dial 14 in the region c includes a valley portion 143 depressed upward and a ridge portion 144 protruding downward adjacent to the valley portion 143. Irregularities are formed.

  In the present embodiment, the lower surface in the region b of the dial 14 includes a valley portion 147 that is depressed upward and a ridge portion 148 that protrudes downward adjacent to the valley portion 147. Irregularities are formed.

  Further, in the present embodiment, as shown in FIG. 3, the irregularities are formed such that the shapes of the bottom of the valley and the top of the mountain in the cross-sectional view are different for each of the regions a to c. The details of the difference in light transmittance due to the difference in the shape of the unevenness will be described later with reference to FIG.

  The unevenness may be formed concentrically on the lower surface of the dial 14 as shown in FIG. 4A, or may be formed in a spiral shape as shown in FIG. 4B. 4 (a) and 4 (b), the solid line indicates the top of the ridge, and the portion between the solid lines indicates the bottom of the valley. However, the shape of the concavities and convexities shown in FIGS. 4A and 4B is an example, and may be formed, for example, in a stripe shape or a radial shape, and is not limited to a uniform pattern, and is decorative. It may be a pattern in which a typical pattern is formed.

  Further, with reference to FIG. 5, details of light transmission in the unevenness formed on dial 14 will be described. FIG. 5 is a diagram for explaining light transmission in the valleys of the unevenness formed on the dial of the present embodiment.

  The dashed line in FIG. 5 indicates the bottom 143 a of the valley 143 having a rectangular cross section. 5 indicates the optical path of light incident on the bottom 143a of the valley 143 formed in a square shape, and the incident light incident on the interface between the lower surface of the dial 14 and the air layer 24. Light 11 and transmitted light (refracted light) 12 and reflected light 13 at the interface are shown. The solid line arrow in FIG. 5 indicates the optical path of light incident on the bottom 141 a of the valley 141 having a rounded cross-sectional shape, and is incident on the interface between the lower surface of the dial 14 and the air layer 24. 2 shows incident light L1 and transmitted light (refracted light) L2 at the interface.

  Here, it is known that the reflectance of light depends on the incident angle (Fresnel's equation). Specifically, it is known that the reflectance increases as the incident angle of light incident on the interface increases, and the reflectance decreases as the incident angle decreases. In other words, it is known that the transmittance decreases as the incident angle of the light incident on the interface increases, and the transmittance increases as the incident angle decreases. That is, the transmittance of the light (incident angle 0 degree) perpendicularly incident on the interface is the highest. Here, the reflectance is a ratio of a reflected light beam to a light beam incident on an interface between substances having different refractive indices. The transmittance is a ratio of a transmitted light beam to a light beam incident on an interface between different substances.

  In FIG. 5, for simplicity of description, light incident perpendicularly (90 degrees) to the upper surface 145 of the dial 14 is reflected at the interface between the dial and the air layer at the bottom of the valley, An example of transmission is shown. In the present embodiment, the upper surface 145 of the dial 14 is a flat surface.

  Here, the cross-sectional shape of the bottom portion 143 a of the valley portion 143 is square, and a slope inclined at a predetermined angle with respect to the upper surface 145 is formed. The light 11 which is perpendicularly incident on the upper surface 145 of the dial 14 is incident on a slope forming the bottom 143a at a predetermined incident angle, and a part thereof is reflected.

  On the other hand, the cross-sectional shape of the bottom 141a of the rounded valley 141 has a smaller inclination with respect to the upper surface of the dial 14, as compared with the configuration of the square bottom 143a. Therefore, the angle of incidence of light incident on the interface between the bottom 141 a of the valley 141 and the air layer 24 is small. Therefore, the reflectance of light at the interface between the bottom 141a of the valley 141 having a rounded cross section and the air layer 24 is small, and the transmittance is large. Therefore, the amount of light reaching the solar cell 30 arranged below the dial 14 is larger than that of the square bottom 143 a, and the amount of power generated by the solar cell 30 is larger.

  As described above, the bottom 141a of the valley 141 is formed in a rounded shape, so that the light transmittance can be improved and the power generation amount in the solar cell 30 can be improved. By forming the top portion 142a of the ridge portion 142 with a rounded shape, the light transmittance can be improved, and the amount of power generation in the solar cell 30 can be increased. When the bottom 141a and the top 142a are rounded at the same radius of curvature, the transmittance is improved by making the bottom 141a round, and the transmittance is improved by making the top 142a round. Greater than improvement. This is because the bottom 141a is expected to improve the transmittance for all light incident thereon, while the top 142a is rounded for light incident from outside the dial 14 to the top 142a. This is because the transmittance cannot be expected to be improved due to the banding. Therefore, in order to improve the transmittance, it is preferable that the radius of curvature at the bottom is larger than the radius of curvature at the top.

  Next, the configuration of the solar cell 30 and the configuration of the dial 14 will be described with reference to FIGS. FIG. 6 is a plan view showing the solar cell according to the present embodiment. FIG. 7 is a plan view schematically showing the dial according to the present embodiment. In FIG. 7, illustration of the unevenness is omitted. FIG. 8 is a cross-sectional view taken along the line BB of FIG. 7 and a diagram illustrating a relationship between transmittance and reflectance.

  As shown in FIG. 6, the solar cell 30 includes a substrate 30b having a shape in which the direction from 10 o'clock to 2 o'clock is cut out in a fan shape. In the example shown in FIG. 6, the angle formed by the notch 30c is 120 °. As described above, the patch antenna 20 is arranged in the area inside the notch 30c (the area where the solar cell 30 does not exist; hereinafter, referred to as the non-arranged area M) so that the receiving surface faces the windshield 32 side. Is done. The angle formed by the cutout portion 30c may be any angle as long as the angle can accommodate the patch antenna 20.

  In the present embodiment, a region where the solar cell 30 is not present is referred to as a non-arranged region M, whereas a region where the solar cell 30 is present and power is generated is a power generation region E and the solar cell 30 is present. The region in which power generation is not performed is called a non-power generation region N.

  A plurality of engaging portions (concavo-convex shape) are provided at positions separated from each other on the peripheral edge of the substrate 30b, and these engaging portions are a body (not shown) or a frame (not shown) housed inside the body 10. It is engaged with the cell support frame. Thus, the substrate 30b is non-rotatably supported in the timepiece 1 with a solar cell. Further, an opening for inserting a pointer shaft is formed in the center of the solar cell 30, and a plurality of cells 30a as power generation units each including a semiconductor thin film and an electrode are formed on the surface. The area where the cell 30a is provided corresponds to the power generation area E described above. The region where the opening is formed and the region where the dividing line dividing the cell 30a is formed correspond to the non-power generation region N described above. Hereinafter, a region where the opening is formed is referred to as a non-power generation region N1, and a region where the dividing line is formed is referred to as a non-power generation region N2.

  In the present embodiment, irregularities having different shapes are formed on the lower surface of the dial 14 in a region overlapping the power generation region E and a region overlapping the non-arrangement region M in plan view. That is, in the dial 14, irregularities are formed such that the transmittance increases in a region a overlapping the power generation region E in a plan view, and irregularities such that the transmittance decreases in a region c overlapping the non-arranged region M in plan view. Was formed. Further, in a region b overlapping a region adjacent to the non-arranged region M in the region overlapping the power generation region E, the unevenness is formed so that the transmittance is lower than the region a and the transmittance is higher than the region c.

  As shown in the upper part of FIG. 8, the transmittance and the reflectance of the light on the dial 14 are such that the higher the one, the lower the other, and the lower the one, the higher the other. That is, as the transmittance increases, the reflectance decreases, the amount of light transmitted through the dial 14 increases, and the amount of power generated by the solar cell 30 increases. On the other hand, the lower the transmittance is, the higher the reflectance is, the amount of light transmitted through the dial 14 is small, and the amount of power generation in the solar cell 30 is small.

  In the present embodiment, irregularities are formed on the lower surface of the dial 14 so that the light transmittance of the dial 14 in the region a overlapping the power generation region E in plan view is increased. Specifically, as shown in FIG. 3, irregularities were formed such that the cross-sectional shape of the bottom 141a and the top 142a was rounded. With such a configuration, the amount of light transmitted through the dial 14 increases, and the amount of power generated by the solar cell 30 can be maintained and improved. According to the knowledge of the inventor of the present application, the light transmittance increases when the cross-sectional shape of the irregularities forms a sine curve. Therefore, as shown in FIG. 3, in the present embodiment, the cross-sectional shape of the irregularities on the lower surface of the dial 14 in the region a is a shape that draws a sine curve.

  In FIG. 3, in a region a on the lower surface of the dial 14, the width of the valley portion 141 and the width of the mountain ridge portion 142 in the direction orthogonal (intersecting) to the thickness direction of the dial 14 are the same. However, the present invention is not limited to this, and the width of the valleys 141 in the direction orthogonal to the thickness direction of the dial 14 may be larger than the width of the ridges.

  On the other hand, irregularities were formed on the lower surface of the dial 14 so that the transmittance of the dial 14 in the area c overlapping the non-arranged area M was reduced in plan view. Specifically, as shown in FIG. 3, the unevenness was formed so that the cross-sectional shape of the bottom 143a and the top 144a was square. This is because, in the region c, the solar cell 30 is not disposed below the dial 14, so that light transmitted through the region c does not contribute to power generation. When the transmittance is high, the amount of light reflected inside the timepiece and coming out via the dial 14 increases accordingly. As a result, the internal structure of the timepiece can be visually recognized from the outside via the dial 14, which is not preferable from an aesthetic point of view.

  Further, in the region b, the unevenness was formed such that the cross-sectional shape of the bottom portion 147a and the top portion 148a became a rounded shape having a smaller radius of curvature than the bottom portion 141a and the top portion 142a of the region a. In the region b, the irregularities were formed such that the light transmittance was increased stepwise or continuously from the region c side to the region a side. Specifically, as shown in FIG. 3, the cross-sectional shape of the bottom 147 a and the top 148 a is more rounded on the region a side than on the region c side of the region b, which is larger in radius of curvature. Irregularities were formed. With such a configuration, the boundary between the region where the solar cell 30 is disposed and the region where the solar cell 30 is not disposed becomes difficult to be seen from the outside, and the appearance is suppressed from being impaired.

  In the present embodiment, the unevenness is formed on the lower surface of the dial 14 so that the transmittance of the dial 14 in the area c of the dial 14 overlapping the non-arranged area M is reduced, but is not limited thereto. However, even in a region overlapping with the non-power generation region N1 where the opening of the solar cell 30 is formed or the non-power generation region N2 where the dividing line is formed, the lower surface of the dial 14 is formed so as to have low transmittance. May be. Thereby, the reflectance in a region overlapping with the opening or the dividing line of the solar cell 30 is increased, and the opening or the dividing line becomes difficult to be visually recognized from the outside, and the appearance is suppressed from being impaired.

  In addition, the shape of the solar cell is not limited to the one in which the fan-shaped notch as shown in FIG. 6 is formed. For example, the solar cell may be a ring-shaped (doughnut-shaped) solar cell with a central portion cut out, or a C-shaped solar cell with a part of the ring shape cut out. Further, contrary to the ring shape, the solar cell may be provided only near the center of the dial, and the non-arranged area M may be near the outer periphery of the dial. Further, the outer shape is not limited to a circular shape, and may be a solar cell having a square outer shape. In any case where the solar cell of any shape is adopted, in the dial 14, the light transmittance of the area overlapping the power generation area E of the solar cell is increased, and the area overlapping the non-power generation area N and the non-arranged area M is increased. It is good to make light transmittance low.

  FIG. 9 is a cross-sectional view schematically showing a dial and a solar cell according to a first modification of the present embodiment. In FIG. 3 and the like, a configuration in which unevenness having a rounded cross section is formed on the lower surface of the dial 14 has been described. However, the present invention is not limited to this. For example, as in a dial 140 shown in FIG. The most depressed portion of the bottom portion 141a in the region a overlapping the power generation region E may be a plane parallel to the upper surface 145. Similarly, the most protruding portion of the top 142a may be a plane parallel to the upper surface 145. This is because transmittance is improved by making the cross-sectional shape of the bottom 141a and the top 142a a surface that is not inclined with respect to the upper surface 145. In the region c overlapping the non-arranged region M that does not contribute to power generation, the bottom 141a and the top 142a may have a square cross-sectional shape. In the region b between the region a and the region c, irregularities were formed such that the light transmittance was increased stepwise or continuously from the region c to the region a. Specifically, as shown in FIG. 9, on the side of the area c in the area b, the cross-sectional shape of the bottom 147 a is square, and the most protruding part of the top 148 a is a plane parallel to the upper surface 145. On the side of the region a in the region b, the most protruding portion of the top 148a is made parallel to the upper surface 145, and the most depressed portion of the bottom 147a is made parallel to the upper surface 145. A flat surface. By gradually changing the shape of the irregularities in the region b in this manner, it is difficult to externally recognize the boundary between the region where the solar cells 30 are arranged and the region where the solar cells 30 are not arranged, while securing the amount of power generation in the power generation region E. . Further, for example, in the area b, the area of the plane of the bottom 147a of the valley 147 and the area of the plane of the top 148a of the ridge 148 gradually increase from the area c to the area a. The unevenness may be formed as described above.

  It should be noted that it is possible to appropriately adopt which of the bottom and the top has a square cross section, a rounded shape, or a degree of the rounded shape. Irregularities may be formed on the lower surface of the dial 140 such that the light transmittance at least in the region a is high and the light transmittance in the region c is low, regardless of where and what shape is adopted.

  FIG. 10 is a cross-sectional view schematically illustrating a dial and a solar cell according to a second modification of the present embodiment. In the dial shown in FIGS. 3, 9, and the like, a configuration is adopted in which the shape of the unevenness is changed depending on which region of the solar cell 30 overlaps, but in the second modification, the lower surface of the dial 240 is A configuration is adopted in which irregularities are formed on the surface, and a coating material 50 is applied on the irregularities to make the transmittance different for each region.

  Specifically, in the second modified example, similarly, in any of the regions a to c, irregularities having a rectangular cross section are formed on the lower surface of the dial 240. Then, the paint 50 is applied to the unevenness of the area a overlapping the power generation area E in plan view, and the unevenness of the area b adjacent to the area c not overlapping the power generation area E among the areas overlapping the power generation area E is thinner than the area a. Paint 50 was applied. In the area c which does not overlap the power generation area E, the paint 50 is not applied.

  In a region where the paint 50 is applied, the paint 50 forms an interface with the air layer 24, and the interface forms a gentle slope. In addition, for example, when the refractive index of the paint 50 and the dial 240 is substantially equal to each other and is larger than the refractive index of the air layer 24, the reflection and refraction of light are higher than the interface between the dial 240 and the paint 50. , Dominant at the interface between the paint 50 and the air layer 24. Therefore, the light transmittance increases in the region a where the gentle inclination is formed by the application of the paint 50.

  The light transmittance of the dial 14 is adjusted by applying the paint 50 to any area on the lower surface of the dial 14 and adjusting the amount (film thickness) of the applied paint 50 for each area. Is also good. Further, depending on the material of the paint 50, the region where the paint 50 is applied may have lower light transmittance than the region where the paint 50 is not applied. When applying such a coating material 50, the amount of the coating material 50 applied in the region a may be reduced and the amount of the coating material 50 applied in the region c may be increased.

  Also, it is not necessary to form irregularities on the lower surface of the dial 240, and the transmittance in each region may be made different only by applying the paint 50. In any case, any structure may be used as long as the light transmittance in the region a overlapping the power generation region E is high and the light transmittance in the region c not overlapping the power generation region E is low.

  As described above, the embodiment according to the present invention has been described. However, 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 to this. 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 the present specification includes such modifications.

  1 Clock with solar cell, 10 body, 11 band fixing part, 12 buttons, 13 crown, 14, 140, 240 dial, 141, 143, 147 valley, 141a, 143a, 147a bottom, 142, 144, 148 mountain Strip, 142a, 144a, 148a Top, 145 upper surface, 15 hour hand, 16 minute hand, 17 second hand, 20 patch antenna, 30 solar cell, 30a cell, 32 windshield, 36 back cover, 38 movement, 47 semi-transmissive reflector, 49 Time character, 50 paints.

Claims (13)

A dial including a high light-transmitting high-transmission area and a light-transmitting low-transmission area lower than the high-transmission area,
A solar cell including at least a power generation region that generates power by incidence of light transmitted through the dial,
Has,
The low transmission region is provided so as to overlap a non-power generation region that does not contribute to power generation at least in the solar cell or a non-arrangement region where the solar cell is not provided, in a plan view,
The high transmission region is provided to overlap at least the power generation region in a plan view,
Clock with solar battery. The lower surface in the high transmission region and the low transmission region of the dial is a valley portion depressed on the upper surface side of the dial, and a ridge portion projecting to the lower surface side adjacent to the valley portion. Including irregularities consisting of
The cross-sectional shape of at least the bottom of the valley is a rounded shape,
The cross-sectional shape of the bottom portion in the high transmission region is a larger rounded shape than the cross-sectional shape of the bottom portion in the low transmission region,
The timepiece with a solar cell according to claim 1. The cross-sectional shape of the top of the mountain strip is a rounded shape,
The cross-sectional shape of the top portion in the high transmission region is a larger rounded shape than the cross-sectional shape of the top portion in the low transmission region,
The timepiece with a solar cell according to claim 2. The radius of curvature at the bottom of the valley is greater than the radius of curvature at the top of the ridge,
The timepiece with a solar cell according to claim 2. The dial has a light transmission lower than the high transmission region, and a middle transmission region having a higher light transmission than the low transmission region,
The middle transmission region is provided between the high transmission region and the low transmission region,
The timepiece with a solar cell according to claim 1. In the middle transmission region, the light transmittance is increased stepwise or continuously as going from the low transmission region side to the high transmission region side,
A timepiece with a solar cell according to claim 5. The lower surface in the high transmission region and the low transmission region of the dial is a valley portion depressed on the upper surface side of the dial, and a ridge portion projecting to the lower surface side adjacent to the valley portion. Including irregularities consisting of
At least in the high transmission region, at least the shape of the bottom of the valley is flat.
The timepiece with a solar cell according to claim 1. The dial has a light transmission lower than the high transmission region, and a middle transmission region having a higher light transmission than the low transmission region,
The middle transmission region is provided between the high transmission region and the low transmission region, and includes at least the valley portion having a flat bottom surface.
In the medium transmission region, the area of the plane of the bottom of the valley portion is gradually increased as going from the low transmission region side to the high transmission region.
A timepiece with a solar cell according to claim 7. The lower surface in the high transmission region and the low transmission region of the dial is a valley portion depressed on the upper surface side of the dial, and a ridge portion protruding on the lower surface side adjacent to the valley portion. Including irregularities consisting of
The cross-sectional shape of the bottom of the valley in the high transmission region, or at least one of the cross-sectional shape of the top of the ridge, is a rounded shape,
At least one of the cross-sectional shape of the bottom of the valley in the low transmission region, or the cross-sectional shape of the top of the ridge is square.
The timepiece with a solar cell according to claim 1. Paint is applied to at least one of the high transmission region and the low transmission region of the lower surface of the dial,
The timepiece with a solar cell according to claim 1. The high transmission region includes a surface whose cross-sectional shape forms a sine curve,
The timepiece with a solar cell according to claim 1. The valley portion and the mountain portion are formed concentrically or spirally on the lower surface,
The timepiece with a solar cell according to any one of claims 2 to 4. The dial is made of a polycarbonate resin or an acrylic resin,
The timepiece with a solar cell according to claim 1.

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