Display devices, electronic devices, and clocks

Abstract

To improve the visibility of an inner structure arranged below a liquid crystal panel when a transmissive liquid crystal panel is included.SOLUTION: A display device 1 includes: a liquid crystal layer 20 in which a liquid crystal material 21 is inserted in a transparent electrode; and a transmissive liquid crystal panel 2 which includes an upper polarizer 25 arranged on a visual recognition side of the liquid crystal layer 20 and a lower polarization plate 26 arranged on a non-visual recognition side of the liquid crystal layer 20. A film 3 having a moth-eye structure is arranged between the non-visual recognition side of the lower polarization plate 26 arranged on the non-visual recognition side of the liquid crystal layer 20.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a display device, an electronic device, a timepiece, and a method for manufacturing a display device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, there are known modules (electronic devices) such as timepieces that include a skeleton display device that is configured so that the inside can be visually confirmed. For example, Patent Document 1 describes a clock that has a liquid crystal display element above the hands that display the time in an analog manner (in Patent Document 1, the hour and minute hands), and by appropriately setting the liquid crystal display element to a transparent state, it is possible to see through the movement of the hands that are located below the liquid crystal display element (on the non-visible side). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-148565 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional technology described in Patent Document 1 merely makes it possible to view the structure arranged below the liquid crystal display element (on the non-visible side), and does not sufficiently take into consideration transparency, visibility, etc.

[0005] The present invention is intended to solve these problems, and aims to provide a display device, electronic device, watch, and method for manufacturing a display device that can improve the visibility of the internal structure located below the liquid crystal panel when a transmissive liquid crystal panel is included. [Means for solving the problem]

[0006] In order to solve the above problems, the display device according to the present invention comprises: a transmissive liquid crystal panel including a liquid crystal layer in which a liquid crystal material is sandwiched between transparent electrodes, an upper polarizing plate disposed on the viewing side of the liquid crystal layer, and a lower polarizing plate disposed on the non-viewing side of the liquid crystal layer; The optical element is characterized in that a film having a moth-eye structure is disposed on the non-viewing side surface of the lower polarizing plate. Effect of the Invention

[0007] According to the present invention, when a transmissive liquid crystal panel is provided, it is possible to improve the visibility of the internal structure disposed below the liquid crystal panel. [Brief description of the drawings]

[0008] [Figure 1] FIG. 2 is a front view of the timepiece according to the embodiment. [Diagram 2] FIG. 2 is an exploded perspective view of a main part of the module according to the embodiment. [Diagram 3] FIG. 2 is a schematic cross-sectional view of a main part of a module according to an embodiment. [Figure 4] FIG. 2 is a schematic side view of a main part of a liquid crystal panel. [Diagram 5] FIG. 2 is a perspective view showing a schematic diagram of a sheet roll around which a sheet constituting a film having a moth-eye structure in the present embodiment is wound. [Figure 6] FIG. 6 is a plan view showing a single film cut out from the sheet shown in FIG. 5. [Figure 7] FIG. 2 is a plan view of a backlight unit according to the embodiment. [Figure 8] FIG. 2 is a schematic cross-sectional view of a portion of a substrate in the embodiment. [Figure 9] FIG. 1 is a schematic cross-sectional view of a portion of a conventional substrate. [Figure 10] FIG. 11 is a schematic plan view showing a modified example of the liquid crystal panel in the embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 1 to 9, an embodiment of a display device, electronic device, timepiece, and a manufacturing method of a display device according to the present invention will be described. In this embodiment, the electronic device is a module 100 provided in a timepiece 200 (a wristwatch in the illustrated example), and a display device 1 is provided in this module 100. In addition, the embodiments described below are subject to various limitations that are technically preferable for implementing the present invention, but the scope of the present invention is not limited to the following embodiments and illustrated examples.

[0010] [composition] FIG. 1 is a front view of the timepiece according to this embodiment. As shown in FIG. 1, a watch 200 in this embodiment has an exterior case 201 and a module 100 , which is an electronic device housed within the exterior case 201 . The exterior case 201 is made of a relatively hard synthetic resin such as biomass plastic, engineering plastic, super engineering plastic, or a metal material such as titanium or stainless steel (SUS). The material from which the main body case is made is not limited to those exemplified here. For example, it may be made of various ceramics.

[0011] A pair of band attachment parts 202 for attaching a band (not shown) are provided on the outer surface of exterior case 201 at upper and lower positions in FIG. 1 (the 12 o'clock and 6 o'clock positions in an analog watch). Although not shown, various operation buttons (push buttons, crown, etc.) for a user to perform various input operations are provided on the left and right sides of exterior case 201 in Fig. 1. Exterior parts such as a bezel may be attached to exterior case 201.

[0012] The exterior case 201 is formed in a hollow short column shape that is open at least at the upper part in the thickness direction (the viewing side, the front side of the watch), and the internal hollow portion forms a storage space for storing module 100, which is the electronic device in this embodiment. Fig. 2 is an exploded perspective view of a main part of a module provided in the watch shown in Fig. 1, and Fig. 3 is a schematic cross-sectional view of a main part of the module shown in Fig. 2. In the following, the direction in which a watch 200 provided with a display device 1 described later is viewed (the direction from top to bottom in Fig. 3, indicated by a white arrow in the figure) is referred to as a "viewing direction D". In the following description, the viewing side (front side) is the upper side of the viewing direction D in Fig. 3, and the non-viewing side (back side) is the lower side of the viewing direction D.

[0013] The module 100 of this embodiment includes a display device 1, a substrate 5, and the like. Specifically, as shown in Fig. 2, the module 100 includes a first housing 101 and a second housing 102. The first housing 101 and the second housing 102 are formed in a substantially disk shape from, for example, various synthetic resins. As shown in FIGS. 2 and 3, the display device 1, the substrate 5, and the like are sandwiched between the first housing 101 and the second housing .

[0014] In this embodiment, a board pressing member 103 is disposed on the back side of the second housing 102 (the lower side in FIG. 3, the side that becomes the non-visible side when the module 100 is incorporated into the exterior case 201 of the watch 200). The board pressing member 103 has a locking claw portion 103a that stands upright toward the visible side of the watch 200. After the first housing 101 and the second housing 102 are fitted together with the display device 1, board 5, etc. sandwiched therebetween, the board pressing member 103 is attached so that the locking claw portion 103a is locked to the first housing 101, and the first housing 101, second housing 102, display device 1, board 5, etc. are integrated. A battery 104, such as a button battery, is disposed on the back surface side of the second housing 102, and the battery 104 is held in place by the attachment of a battery pressing member 105.

[0015] The display device 1 of this embodiment includes a liquid crystal panel 2 and a backlight unit 4, and is configured to display the time and various information by partially blocking or transmitting the light emitted by the backlight unit 4. More specifically, the display device 1 has the following configuration.

[0016] FIG. 4 is a schematic side view showing a liquid crystal panel of the display device shown in FIG. 4, first, the liquid crystal panel 2 has a liquid crystal layer 20 in which a transparent liquid crystal material (liquid crystal composition) 21 is sandwiched between two transparent substrates 22. In the liquid crystal layer 20, a sealant 23 is provided around the liquid crystal material 21. As a result, the liquid crystal material 21 sandwiched between the two transparent substrates 22 is sealed by the sealant 23, so that the liquid crystal material 21 does not leak out. A transparent electrode (not shown) is formed on the entire inner surface of each transparent substrate 22, and the liquid crystal material 21 is sandwiched between the transparent electrodes. A connection portion 24 of the transparent electrode is exposed at the end of the transparent substrate 22. One end of a connector member 6 is connected to this connection portion 24. The other end of the connector member 6 is electrically connected to a connection terminal portion 55 of the substrate 5, which will be described later.

[0017] Although not shown in the figure, an alignment film made of, for example, a polyimide material is arranged on the inside of each transparent electrode of the two transparent substrates 22, so that the alignment state of the liquid crystal material 21 can be switched depending on the voltage applied to the transparent electrodes. 2, the liquid crystal panel 2 is provided with a lighting pattern section (not shown) that displays a predetermined display such as time and date when a voltage is applied to the transparent electrodes. By switching the orientation state of the liquid crystal material 21, numbers indicating the time and the like are appropriately displayed in the lighting pattern section.

[0018] An upper polarizer 25 is disposed on the visible side of the liquid crystal layer 20 (upper side in FIG. 3), and a lower polarizer 26 is disposed on the non-visible side of the liquid crystal layer 20 (lower side in FIG. 3). In this manner, the liquid crystal panel 2 has a configuration in which the liquid crystal layer 20 is sandwiched between two upper and lower polarizing plates (the upper polarizing plate 25 and the lower polarizing plate 26). Depending on what is used as the lower polarizing plate 26, the color tone of the lighting pattern portion displayed on the liquid crystal panel 2 when it is lit can be selected. In this embodiment, in order to achieve both background transparency and display contrast on the liquid crystal panel 2, an "iodine-based transmissive polarizing plate" is used as the lower polarizing plate 26. By using an "iodine-based transmissive polarizing plate" for the lower polarizing plate 26, the color tone of the lighting pattern portion displayed on the liquid crystal panel 2 when lit can be made black, and the background can be made transparent.

[0019] In this embodiment, the film 3 is disposed on the non-viewing side (the lower side, back side in FIG. 3) of the lower polarizing plate 26. The film 3 is a film having a moth-eye structure. A film having a moth-eye structure is a film having a surface structure that mimics the fine protrusion structure of a moth's eye (moth eye). Specifically, for example, small protrusions about several hundred nm in height are formed at a period (pitch) of about 100 nm, thereby providing a continuous uneven shape on the surface of the film 3. As the film 3 having a moth-eye structure, for example, a Mosmite (registered trademark) film or the like can be used.

[0020] Since the film 3 has such a fine protrusion structure (moth-eye structure), when light is incident on the film 3, the film 3 can suppress reflection due to a birefringence effect that continuously changes the refractive index. For this reason, films having a moth-eye structure are generally used as anti-reflection films. Another feature of film 3, due to the fine protrusion structure (moth-eye structure), is that when linearly polarized light passes through it, the direction of change becomes random, close to that of natural light.

[0021] The film 3 having the moth-eye structure is cut out from a sheet 30 wound in a roll by punching out the film 3 according to the shape of an object to be disposed (in this embodiment, the lower polarizing plate 26). Fig. 5 is a perspective view showing a sheet roll on which sheets constituting a film having a moth-eye structure are wound. In Fig. 5, an example of the arrangement of the film 3 when cutting out the film 3 from the sheet 30 is shown by a broken line. In Fig. 5, the rotation axis of the sheet roll (rolled sheet 30) is shown as "Ax". The sheet 30 is usually produced while being stretched in a stretching direction (machine direction, which is the absorption axis direction in this embodiment, referred to as "MD direction" in Fig. 5 etc.) along the circumferential direction of the roll perpendicular to the rotation axis Ax.

[0022] FIG. 6 is a plan view showing a single film cut out from the sheet shown in FIG. In this embodiment, the film 3 having a moth-eye structure is placed on the non-visible side (the lower side, back side in Figure 3) of the lower polarizing plate 26 so that the MD direction of the film 3 during sheet manufacturing is oriented at 45 degrees to the polarization axis of the upper polarizing plate 25 (referred to as "Pa" in Figure 6).

[0023] As shown in FIG. 2 and other figures, a backlight unit 4 is provided on the non-viewing side of the liquid crystal panel 2 (the lower / rear side of the display device 1). FIG. 7 is a plan view showing a backlight unit. As shown in FIG. 7, the backlight unit 4 includes a frame 41, a light guide plate 42 fitted in the frame 41, and a light source 43.

[0024] The frame 41 is a frame body formed into a shape corresponding to the shape of the liquid crystal panel 2, and holds a light guide plate 42. The light guide plate 42 is formed, for example, by injection molding a transparent resin material (such as polycarbonate). A light source 43 is disposed at one end of the frame 41 (the left side in the illustrated example). The light source 43 is, for example, an LED. The light guide plate 42 is a plate-like member having a shape corresponding to almost the entire surface of the liquid crystal panel 2. A dot pattern is formed on the entire surface of the light guide plate 42. There is no particular limitation on the method of forming the dot pattern on the light guide plate 42. For example, the dot pattern may be molded together with the light guide plate 42 when the light guide plate 42 is molded, or the dot pattern may be formed by injection molding into a plate and then laser processing or the like.

[0025] Since the dot pattern is formed on the light guide plate 42, the light incident on the light guide plate 42 from the light source 43 is randomly reflected and diffused, and the entire light guide plate 42 emits surface light. Then, the light emitted from the backlight unit 4 is incident on the liquid crystal panel 2 as surface emitted light (backlight light). In the conventional light guide plate 42, the dot pattern is formed sparsely (sparsely) depending on the location, so that a sufficient amount of light can be obtained closer to the light source 43, and the dot pattern is formed densely in the farther away from the light source 43 in order to sufficiently diffuse even a small amount of light and ensure brightness.

[0026] In contrast, in the light guide plate 42 of this embodiment, a substantially uniform dot pattern is formed regardless of the distance from the light source 43 . Specifically, the size of the dots that make up the dot pattern is maintained at the same level as in the past, and the dots are formed at a generally uniform pitch overall. That is, the dot pattern of the light guide plate 42 in this embodiment is appropriately adjusted so that the dots are approximately uniform overall with an intermediate degree of variation in dot density depending on the distance from the light source 43 as in the conventional example.

[0027] 7, region b of light guide plate 42 is enlarged to show a schematic example of a dot pattern outside frame 41. In light guide plate 42 of the present embodiment, the dot pattern when enlarged is the same as that of region b, even in a portion closer to light source 43 than region b (region a in FIG. 7) and in a portion farther from light source 43 than region b (region c in FIG. 7). That is, in this embodiment, in an area a of the light guide plate 42 close to the light source 43, the dots are somewhat denser than in the past, and in an area c of the light guide plate 42 far from the light source 43, the dots are somewhat sparser than in the past.

[0028] Conventionally, unless the liquid crystal panel is a transmissive type, the dots are sparser in the region of the light guide plate 42 closer to the light source 43, and the dots are denser in the region farther from the light source 43, as described above. However, in a transmissive liquid crystal panel 2 such as in this embodiment, the dot pattern of the light guide plate 42 creates a frosted glass-like appearance, causing the substrate 5 to look blurred. That is, in a transmissive liquid crystal panel 2 such as in this embodiment, this means that the substrate transparency of the display unit becomes uneven. Therefore, by maintaining the dot size while making the pitch uniform for the dot pattern, the dot density is reduced compared to conventional methods, and the transparency of the light guide plate is improved.

[0029] The substrate 5 is mounted with various electronic components (not shown) that enable the watch 200 to perform various operations. The substrate 5 also has wiring patterns 52, electrodes, etc. that connect these electronic components. Examples of electronic components may include a main IC (integrated circuit) 56 such as a microcomputer, an external storage unit (such as a flash memory), a large-capacity capacitor, a watch module related to various functional operations such as communication and measurement, a quartz crystal oscillator, etc. The substrate 5 receives power supply from a battery 104 to operate various electronic components. For example, the main IC 56 counts time (which may include date information) using a clock signal according to the oscillation of a quartz crystal oscillator. The main IC 56 also causes the display screen of the liquid crystal panel 2 of the display device 1 to display the time and other information. The substrate 5 may be a laminated substrate having multiple layers.

[0030] FIG. 8 is a schematic cross-sectional view of a portion of a substrate in the embodiment, and FIG. 9 is a schematic cross-sectional view of a portion of a conventional substrate. 8 and 9, the substrates 5 and 5a are provided with wiring patterns 52 and 52a made of copper foil (Cu) on the surface of a base material 51. The substrates 5 and 5a are also provided with resist layers 54 and 54a as insulating layers to prevent short circuits between the wiring patterns 52 and 52a. As shown in FIG. 9, in a conventional substrate 5a, a wiring pattern 52a is provided using a conductor such as copper foil, and then a resist layer 54a is formed using an insulating resist ink. Thereafter, a gold (Au) plating layer 53a is provided to prevent corrosion, etc., on the portion where the resist layer 54a is not provided and the wiring pattern 52a is exposed to the outside.

[0031] 8, in the substrate 5 of this embodiment, a gold-plated layer 53 is disposed on a wiring pattern 52 made of a conductor such as copper foil, and a resist layer 54 that is transparent or semi-transparent to at least the gold-plated layer 53 is disposed on the gold-plated layer 53. In other words, the gold-plated layer 53 is visible through the resist layer 54. The resist layer 54 is generally a deep green color, but by disposing the gold plating layer 53 between the wiring pattern 52 and the resist layer 54, the gold plating layer 53 can be seen through under the resist layer 54 compared to when the resist layer 54 is placed directly on the wiring pattern 52, making the color of the substrate 5 appear brighter. Note that a resist ink with a lighter color, such as yellow or white, may be used for forming the resist layer 54. Changing the color of the resist layer 54 itself to a lighter color can also improve the overall visibility of the substrate 5 when the inside of the watch 200 is viewed through the display device 1 including the liquid crystal panel 2 or the like.

[0032] In addition, in this embodiment, a main IC (integrated circuit) 56 is mounted on the substrate 5 as shown in Figures 2 and 3, and a light-shielding cover 7 is arranged at a location corresponding to the main IC (integrated circuit) 56 so as to cover the main IC (integrated circuit) 56. Integrated circuits are very sensitive to external light such as ultraviolet light, and even the slightest amount of light entering the circuit board can cause malfunctions, increased current consumption, and other problems. For this reason, at least the main IC (integrated circuit) 56 among the electronic components mounted on the board 5 is provided with a light-shielding cover 7 to block external light.

[0033] The light-shielding cover 7 may be made of any material capable of blocking external light such as ultraviolet light, and the material from which the light-shielding cover 7 is made is not particularly limited. The size, shape, and area of ​​the light-shielding cover 7 need only cover the main IC (integrated circuit) 56. For example, the light-shielding cover 7 may be a plate-like cover covering the visible side of the main IC (integrated circuit) 56, or may be a cover that surrounds the visible side and side of the main IC (integrated circuit) 56. The light-shielding cover 7 may be configured to cover and hide even the potting and the like applied to the main IC (integrated circuit) 56. A configuration that hides even the potting improves the design when viewed from the outside. Furthermore, from the viewpoint of making the internal configuration of the substrate 5 etc. visible from the outside, it is preferable that the shading cover 7 covers an area slightly larger than the main IC (integrated circuit) 56 and does not cover or conceal components that do not require shading as much as possible, such as the wiring pattern 52.

[0034] Although it depends on the position of the main IC (integrated circuit) 56, which is the object of light shielding, in the examples shown in Figures 1 to 3, the light shielding cover 7 is disposed at approximately the center of the substrate 5. When the light shielding cover 7 is disposed in such a position that is particularly noticeable when the substrate 5 is viewed through the liquid crystal panel 2, the light shielding cover 7 is preferably one with excellent design. For this reason, for example, the light-shielding cover 7 may be formed of a metal such as gold, or may be plated with gold, etc. Also, the surface (the surface on the viewing side) of the light-shielding cover 7 may be decorated with various patterns, logos, engravings, etc., to further improve the design and aesthetic appeal.

[0035] [Effect] When assembling the watch 200, first the module 100, which is an electronic device including the display device 1, is assembled. As shown in Fig. 8, the substrate 5 provided in the module 100 has a conductor layer such as copper foil ("Cu layer" in Fig. 8) provided on a base material 51 (front, back and side surfaces of the base material 51 in Fig. 8), and then gold plating layer 53 ("Au layer" in Fig. 8) is formed thereon by gold plating or the like. Then, etching or the like is performed according to the wiring circuit, and wiring patterning is performed to leave the "Cu layer" and gold plating layer 53 ("Au layer") only in the wiring pattern 52 portion. After that, a resist layer 54 is formed on the "Cu layer" and gold plating layer 53.

[0036] As a result, in the wiring pattern 52 portion, the gold plating layer 53 ("Au layer") is visible under the resist layer 54, and the wiring pattern 52 portion made of the Cu layer appears bright. The color of the substrate 5 as a whole can also be brightened, and good transparency and visibility can be ensured even when viewed through a display device 1 including a liquid crystal panel 2 or the like. Note that various patterns, logos, engravings, and other decorations may be applied to the peripheral portion of the surface of the substrate 5 and other portions that do not affect the electronic components or wiring.

[0037] After the wiring pattern 52 and the like are provided on the substrate 5, electronic components such as a main IC (integrated circuit) 56 are mounted at predetermined positions on the substrate 5 (for example, the center of the visible surface of the substrate 5). Then, the light-shielding cover 7 is placed only at locations corresponding to electronic components that require light shielding, such as the main IC (integrated circuit) 56. The light-shielding cover 7 may be decorated by plating its surface (the surface on the visible side) or by providing various patterns, logos, engravings, etc. For example, in the example shown in Figures 1 and 2, a star-shaped mark is provided as decoration on the visible surface of the light-shielding cover 7.

[0038] Next, a display device 1 having a transmission type liquid crystal panel 2 is assembled. The backlight unit 4 of the display device 1 is configured by attaching a light guide plate 42 formed by injection molding a transparent resin to a frame 41 and arranging a light source 43 at one end of the frame 41. In order to make the backlight unit 4 surface-emitting, a dot pattern is formed on the entire surface of the light guide plate 42. However, if there are many dot patterns, the light guide plate 42 will have a frosted glass-like appearance, and when the inside is viewed through the display device 1, the substrate 5 will look blurred, and the transparency and visibility of the internal structure (e.g., the substrate 5, etc.) on the back side (non-viewing side) of the backlight unit 4 will decrease. In particular, if the dot pattern is made sparse and dense in the part close to the light source 43 and the part far from the light source 43 as in the conventional case, unevenness will occur in the internal transparency and visibility of the substrate 5, etc. between the side where the dots are densely arranged and the part where the dots are sparsely arranged.

[0039] Therefore, in the dot pattern of light guide plate 42 in this embodiment, the dot size is maintained, but the pitch of the dots is made generally uniform, and the density of the dots is constant regardless of the distance from light source 43. Because the dot pattern of light guide plate 42 is generally uniform, no unevenness in transparency occurs when the inside of watch 200 is viewed through display device 1 including light guide plate 42. This allows the backlight unit 4 to maintain its function as a backlight unit that directs surface-emitted light to the liquid crystal panel 2, while increasing the transparency of the light guide plate 42 and improving the transparency and visibility of the internal structure of the substrate 5, etc.

[0040] The liquid crystal panel 2 of the display device 1 has an upper polarizing plate 25 disposed above the liquid crystal layer 20 and a lower polarizing plate 26 disposed below the liquid crystal layer 20, sandwiching the liquid crystal layer 20 from above and below. Of the polarizing plates, an "iodine-based transmissive polarizing plate" is used for the lower polarizing plate 26. This makes it possible to make the lighting color of the lighting pattern portion displayed on the liquid crystal panel 2 black and the background transparent, thereby achieving both background transparency and the contrast of the display on the liquid crystal panel 2. This improves the visibility of the display on the display device 1.

[0041] Furthermore, a film 3 having a moth-eye structure is placed on the lower surface (non-viewing side) of the lower polarizing plate 26. At this time, the MD direction of the film 3 during sheet production is oriented at 45 degrees with respect to the polarization axis of the upper polarizing plate 25 (referred to as "Pa" in FIG. 6). As mentioned above, the light guide plate 42 of the backlight unit 4 is manufactured by injection molding. Due to internal stress (residual stress) that occurs during this molding, a rainbow pattern (optical distortion) appears on the outside when the light guide plate 42 is viewed through the polarizing plates (upper polarizing plate 25, lower polarizing plate 26). In this regard, the film 3 having the moth-eye structure has the property that when linearly polarized light passes through it, it becomes in a state close to unpolarized (randomly oriented) natural light. Therefore, by arranging the film 3 on the lower surface (non-viewing surface) of the lower polarizing plate 26 so that the MD direction of the film 3 during sheet production is oriented at 45 degrees with respect to the polarization axis Pa of the upper polarizing plate 25, it is possible to reduce the rainbow pattern (optical distortion) that appears on the exterior due to the internal stress (residual stress) of the light guide plate 42.

[0042] A backlight unit 4 is placed on the non-visible side of the liquid crystal panel 2 assembled in this manner, and when the display device 1 is completed, the connection portion 24 of the transparent electrode of the liquid crystal panel 2 and the connection terminal portion 55 of the substrate 5 are connected via a connector member 6. Furthermore, the display device 1 and the board 5 are sandwiched between the first housing 101 and the second housing 102, and are integrated by attaching the board pressing member 103. Then, the battery 104 is locked to the non-visible side of the second housing 102 by the battery pressing member 105, and the module 100 is completed. In this embodiment, the timepiece 200 is completed by housing this module 100 inside an exterior case 201.

[0043] As a result, when the clock 200 is viewed from the viewing side, the internal structure of the substrate 5 and the like can be seen through the display device 1 including the liquid crystal panel 2 and the like. In addition, the time and other information displayed on the liquid crystal panel 2 can also be clearly seen.

[0044] [effect] As described above, the display device 1 in this embodiment comprises a transmissive liquid crystal panel 2 including a liquid crystal layer 20 in which liquid crystal material 21 is sandwiched between transparent electrodes, an upper polarizer 25 arranged on the visible side of the liquid crystal layer 20, and a lower polarizer 26 arranged on the non-visible side of the liquid crystal layer 20, and a film 3 having a moth-eye structure is arranged on the non-visible surface of the lower polarizer 26. The light guide plate 42 of the backlight unit 4, which is provided on the non-viewing side of the liquid crystal panel 2, is formed by injection molding of a transparent resin. For this reason, due to internal stress (residual stress) that occurs during formation, a rainbow pattern (optical distortion) appears on the outside when the light guide plate 42 is viewed through the polarizing plates (upper polarizing plate 25, lower polarizing plate 26). In this regard, by providing the film 3 having a moth-eye structure, it is possible to suppress the occurrence of rainbow patterns (optical distortion) to an unnoticeable level when viewed, thereby improving the appearance and quality of the display device 1. This makes it possible to improve the visibility of the internal structure disposed below the liquid crystal panel 2 when the display device is equipped with a transmissive liquid crystal panel 2.

[0045] Moreover, the film 3 of this embodiment is cut out from a long sheet 30 and is disposed so that the longitudinal direction of the long sheet forms an angle of 45 degrees with respect to the polarization axis Pa of the upper polarizing plate 25 . This makes it possible to effectively prevent the occurrence of rainbow patterns (optical distortion) due to internal stress (residual stress) occurring during injection molding of the light guide plate 42 when the film 3 having the moth-eye structure is disposed.

[0046] Furthermore, the display device 1 includes a backlight unit 4 including a light source 43 and a light guide plate 42 on the non-viewing side of the liquid crystal panel 2, and a uniform dot pattern is formed on the light guide plate 42 of the backlight unit 4 regardless of the distance from the light source 43. Particularly in this embodiment, the liquid crystal panel 2 is a transmissive liquid crystal panel. As a result, when the internal structure of the substrate 5 and the like is viewed through the display device 1 including the light guide plate 42, the overall transmittance becomes uniform, resulting in a uniform and easy-to-view state.

[0047] Furthermore, the display device 1 of this embodiment includes a substrate 5 arranged on the non-visible side of the liquid crystal panel 2, and the substrate 5 is provided with a plating layer (gold plating layer 53 in this embodiment) on the visible side of a wiring pattern 52 formed on a base material 51. A resist layer 54 is provided on at least a portion of the visible side of the plating layer (gold plating layer 53 in the embodiment), and the plating layer (gold plating layer 53) is visible through the resist layer 54. The plating layer (gold plating layer 53 in the embodiment) may be provided across the entire width of the visible side of the wiring pattern 52, or a resist layer 54 may be provided to cover at least a portion of the plating layer (gold plating layer 53) in the width direction of the wiring pattern 52.

[0048] In this way, when a gold-plated layer 53 is formed corresponding to the wiring pattern 52 formed on the base material 51, and a resist layer 54 that is at least transparent or semi-transparent to the gold-plated layer 53 is formed on top of the gold-plated layer 53, the gold-plated layer 53 is positioned under the resist layer 54 at least in the area where the wiring pattern 52 is formed. The gold plating layer 53 is visible underneath the resist layer 54, which brightens the color tone of the entire substrate 5, and in the case where the display device 1 is equipped with a transmissive liquid crystal panel 2, excellent transparency is achieved when the internal structure of the substrate 5, etc., disposed below the liquid crystal panel 2 is viewed through the liquid crystal panel 2, etc. Therefore, when the display device 1 is viewed from the viewing side, the internal structure of the wiring pattern 52, etc., formed on the substrate 5 below the liquid crystal display such as the time display can be clearly seen, and the functional beauty of the wiring pattern 52 can be enjoyed. Furthermore, the visibility of the display on the liquid crystal panel 2 is improved by brightening the color tone of the entire substrate 5.

[0049] Further, in this embodiment, a main IC (integrated circuit) 56 is mounted on the substrate 5, and a light-shielding cover 7 is arranged so as to cover the main IC (integrated circuit) 56 only at a location on the substrate 5 corresponding to the main IC (integrated circuit) 56. The main IC (integrated circuit) 56 is sensitive to external light such as ultraviolet light, and may malfunction or experience other problems if exposed to external light. If the substrate 5 is arranged below the transmissive liquid crystal panel 2 so as to be visible, the impact of external light on the main IC (integrated circuit) 56 on the substrate 5 becomes significant. In this regard, by shading the main IC (integrated circuit) 56 with the light-shielding cover 7, even if the substrate 5 is configured to be visible through the liquid crystal panel 2, the main IC (integrated circuit) 56 on the substrate 5 can be protected from external light, thereby preventing malfunctions and other problems from occurring.

[0050] The light-shielding cover 7 of this embodiment may be decorated on the viewing side. In this case, the decoration on the light-shielding cover 7 can be enjoyed when the substrate 5 is viewed through the transmissive liquid crystal panel 2, resulting in excellent design.

[0051] Furthermore, when an electronic device such as the module 100 is equipped with the display device 1 of this embodiment, the internal structure of the internal substrate 5, etc. can be seen through the transmissive liquid crystal panel 2, and the functional beauty of, for example, the wiring pattern 52 formed on the substrate 5 can be enjoyed as an external appearance.

[0052] Furthermore, even when the watch 200 is equipped with the display device 1 of this embodiment, the structure of the internal substrate 5, etc. can be seen through the transmissive liquid crystal panel 2, producing a watch 200 with excellent design that allows the functional beauty of the wiring pattern 52, etc. to be enjoyed as an external appearance.

[0053] [Variations] Although the embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to such an embodiment, and various modifications are possible without departing from the gist of the present invention.

[0054] For example, as shown in FIG. 10, a transparent printed portion 29 may be provided on the transparent substrate 22 of the liquid crystal panel 2 in correspondence with the lighting pattern portion (not shown) of the liquid crystal panel 2. In other words, when a transmissive liquid crystal panel 2 is used to show a substrate 5 etc. arranged below the liquid crystal panel 2 (on the non-visible side) as the external appearance of the display device 1 (and a module 100 or a watch 200 equipped with the display device 1), transparent printing is performed on the parts corresponding to the lighting pattern section and their surroundings in a color tone different from the lighting color (color tone when lit, for example black in this embodiment) when the lighting pattern section is lit so that the background can be seen through. By providing the transparent printed portion 29 in this manner, the color tone around the lighting pattern portion can be stabilized, and the contrast between the background around the lighting pattern portion and the display (lighting color) in the lighting pattern portion can be improved, which is expected to improve the visibility of the time display, etc. displayed in the lighting pattern portion. The transparent printed portion 29 is not limited to being provided by printing on the transparent substrate 22, etc. For example, a filler of a color tone different from the lighting color (e.g., black) may be arranged on the lower surface (non-viewing side surface) of the liquid crystal panel 2 by adhering or the like.

[0055] In addition, in this embodiment, when a transmissive liquid crystal panel 2 is provided, the structure of the surface of the substrate 5 is exemplified as the internal structure arranged below the liquid crystal panel 2, but the internal structure that allows viewing through the liquid crystal panel 2 is not limited to the structure on the surface of the substrate 5. In addition, in the substrate 5 of the present embodiment, the gold plating layer 53 is disposed on the wiring pattern 52, but the present invention is not limited to this configuration. For example, the wiring pattern 52 may be plated with a material other than gold, such as by disposing a silver plating layer on the wiring pattern 52. Even when there is no transmissive liquid crystal panel 2 as in this embodiment, visibility can be improved when viewing the substrate 5 through, for example, a colored back cover that transmits light or a colored transparent member on the viewing side.

[0056] Further, in the present embodiment, the module 100, which is an electronic device having the display device 1, is applied to the watch 200, but the electronic device is not limited to being a watch module. The display device 1 can be applied to any device that incorporates a transmissive liquid crystal panel 2 to perform various displays, and can be widely applied to various electronic devices that display the time and various data, such as various smart watches, sports watches, as well as heart rate monitors, blood pressure monitors, etc.

[0057] Although several embodiments of the present invention have been described above, the scope of the present invention is not limited to the above-described embodiments, but includes the scope of the invention described in the claims and its equivalents. [Explanation of symbols]

[0058] 1 Display device 2 LCD panel 20 Liquid crystal layer 21 Liquid crystal materials 22 Transparent Substrate 23 Sealant 24 Connection 25 Upper polarizing plate 26 Lower polarizing plate 29 Transparent printing section 3. Film with Moth-eye Structure 4 Backlight Unit 41 Frame 42 Light guide plate 43 Light source 5 Substrate 52 Wiring Pattern 53 Gold plating layer 54 Resist layer 55 Connection terminal 56 Main IC (Integrated Circuit) 6 Connector parts 7. Shading cover 100 Modules (Electronic Devices) 101 First Housing 102 Second Housing 103 Circuit board support member 103a Locking claw part 104 Battery 105 Battery holding member 200 Watches 201 Outer case (case) 202 Band attachment part D. Viewing direction Pa Polarization axis

Claims

1. A transmissive liquid crystal panel comprising a liquid crystal layer in which liquid crystal material is sandwiched between transparent electrodes, an upper polarizing plate disposed on the viewing side of the liquid crystal layer, and a lower polarizing plate disposed on the non-viewing side of the liquid crystal layer, A film having a moth-eye structure is placed on the non-visible side of the lower polarizing plate. The film is cut from a long sheet, and the long sheet is arranged so that its longitudinal direction is at a predetermined angle different from the polarization axis of the upper polarizing plate. A display device characterized by the following features.

2. The longitudinal direction of the long sheet is arranged so that it is at a 45-degree angle with respect to the polarization axis of the upper polarizing plate, The display device according to feature 1.

3. The liquid crystal panel is provided with a backlight unit including a light source and a light guide plate on the non-visible side. The light guide plate of the backlight unit has a uniform dot pattern formed on it, regardless of the distance from the light source. The display device according to feature 1.

4. The liquid crystal panel is disposed on the non-visible side and comprises a backlight unit including a light source and a light guide plate, The light guide plate of the backlight unit has a uniform dot pattern formed on it, regardless of the distance from the light source. The display device according to feature 1.

5. A transmissive liquid crystal panel comprising a liquid crystal layer in which a liquid crystal material is sandwiched between transparent electrodes, an upper polarizing plate disposed on the viewing side of the liquid crystal layer, and a lower polarizing plate disposed on the non-viewing side of the liquid crystal layer, The liquid crystal panel comprises a substrate disposed on the non-visible side, A film having a moth-eye structure is placed on the non-visible side of the lower polarizing plate. The substrate has a plating layer provided on the visible side of the wiring pattern formed on the base material. A resist layer is provided in at least a portion of the visible side of the plating layer. The plating layer is visible through the resist layer. A display device characterized by the following features.

6. The aforementioned plating layer is provided across the entire width of the visible side of the wiring pattern. The resist layer is provided so as to cover at least a portion of the widthwise direction of the wiring pattern of the plating layer. The display device according to feature 5.

7. A transmissive liquid crystal panel comprising a liquid crystal layer in which a liquid crystal material is sandwiched between transparent electrodes, an upper polarizing plate disposed on the viewing side of the liquid crystal layer, and a lower polarizing plate disposed on the non-viewing side of the liquid crystal layer, The liquid crystal panel comprises a substrate disposed on the non-visible side, A film having a moth-eye structure is placed on the non-visible side of the lower polarizing plate. The substrate has a plating layer provided on the visible side of the wiring pattern formed on the base material. An integrated circuit is mounted on the aforementioned substrate. A light-shielding cover, with decorative elements on the viewing side, is placed only in the area on the substrate corresponding to the integrated circuit, so as to cover the integrated circuit. A display device characterized by the following features.

8. A display device according to any one of claims 1, 5, and 7, An electronic device characterized by the following features.

9. A display device according to any one of claims 1, 5, and 7, A case for housing the aforementioned display device, A watch characterized by having the following features.

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