Display devices, electronic machines

Abstract

To provide a display device and an electronic device allowing an observer to obtain texture and improving designability for an image of an object having an irregular minute shape on a surface such as wood, stone, paper, a picture such as an oil painting, and fabric displayed on a display surface.SOLUTION: A display device has a surface layer that has light transmittance at the furthest observer side and has an irregular uneven shape at an observer side. In the surface layer, arithmetic average roughness Ra of an uneven shape is 10 μm or larger and 3000 μm or smaller, and a haze value is 40% or larger and 85% or smaller. In the display device, a distance to an image-forming layer for forming an image displayed from points that become the furthest bottom of the uneven shape is 0.3 mm or smaller, and a deterioration rate of luminance in a direction forming 60° relative to a normal direction with luminance in the normal direction of the surface as a reference is 45% or smaller on a surface in which the surface layer is laminated. The display device includes: a sensor section for detecting brightness and a color of external light impinging on a display surface; and an image adjustment section for adjusting the brightness and color of an image.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] This invention relates to a display device and an electronic device. [Background technology]

[0002] Conventionally, various display devices such as liquid crystal displays and organic EL displays have been used in a variety of environments and for a variety of purposes. In addition, image display technologies have been proposed and put into practical use that harmonize the environment in which the display device is used with the image information to be displayed, allowing an observer to visually recognize the texture of an object displayed as an image.

[0003] For example, one such technique is known, as shown in Patent Document 1, in which a sheet is printed with a wood grain pattern or the like that blends in with the surrounding environment in which the display device is used, and multiple fine holes are formed and arranged on the display surface, and an image is projected from behind the sheet. In this way, Patent Document 1 aims to improve design by preventing the viewer from seeing a black screen when no image is displayed, which would cause a sense of incongruity with the surrounding environment. Another known technique is to detect the brightness and color of the external light around the display device using a sensor or the like, and adjust the color tone of the image displayed on the display screen in accordance with that information. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2020 / 196906 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the former method reduces the image resolution, making it difficult to display a clear image. Furthermore, in both methods, when external light is reflected from the display surface of the display device, the viewer perceives the smooth surface shape of the display surface, making it difficult to express the texture of the object. In particular, when an image of an object with a finely textured surface, such as stone, wood, paper, textile, or oil painting, is displayed on the display surface, a discordance arises between the displayed image and the surface shape of the display surface as perceived by the viewer, making it difficult to express the texture.

[0006] The present invention has been made in consideration of such problems, and aims to provide a display device and electronic device that allows the viewer to grasp the texture of an image of an object having a finely textured surface, such as wood, stone, paper, oil paintings and other paintings, textiles, etc., displayed on the display screen, thereby improving the design. [Means for solving the problem]

[0007] (1) A display device displays an image on a display surface, and has a surface layer closest to the viewer that is optically transparent and has an uneven shape on the viewer side, the uneven shape having an arithmetic mean roughness Ra of 10 μm or more and 3000 μm or less, the haze value of the surface layer being 40% or more and 85% or less, the distance in the thickness direction of the display device from the lowest point of the uneven shape to an image forming layer that forms the image to be displayed is 0.3 mm or less, and on the surface on which the surface layer is laminated, the decrease rate of brightness in a direction forming an angle of 60° to the normal direction of the surface is 45% or less, based on the brightness in the normal direction of the surface, and further has a sensor unit that detects the brightness and color of external light incident on the display surface, and an image adjustment unit that adjusts the brightness and color of the image displayed by the display device based on the information on the brightness and color of the external light detected by the sensor unit.

[0008] (2) It is preferable that the depth of the recesses, the height of the protrusions, and the distribution of the recesses and protrusions in the plane direction of the surface layer are irregular.

[0009] (3) It is preferable that the haze value at the outermost surface of the uneven shape is not uniformly distributed in the plane direction of the surface layer.

[0010] (4) It is preferable that the specular reflectance of external light incident on the display device within the display device is 1% or less.

[0011] (5) An electronic device is equipped with the display device described in either (1) or (4) above. [Effects of the Invention]

[0012] According to the present invention, it is possible to provide a display device and electronic device that allows an observer to perceive the texture of an image of an object having a finely textured surface, such as wood, stone, paper, oil paintings, textiles, etc., displayed on the display surface of the display device, thereby improving the design. [Brief explanation of the drawings]

[0013] [Figure 1] 1 is a perspective view showing an electronic device 1 according to an embodiment. [Figure 2] 1 is a diagram illustrating an example of use of an electronic device 1 according to an embodiment. [Figure 3] 1 is a diagram illustrating a layer structure of a display device 10 according to an embodiment. [Figure 4] 1 is a block diagram showing a configuration of a display device 10 according to an embodiment. [Figure 5] FIG. 2 is an enlarged view of a part of a cross section of a surface layer 15 according to the embodiment. [Figure 6] FIG. 1 is a diagram showing the configuration of a display device in Measurement Example 1. [Figure 7] FIG. 10 is a diagram showing the configuration of a display device in Measurement Example 2. [Figure 8] 10 is a graph showing the luminance distribution on the light output surface 12a of the display panel 12 of the display devices of Measurement Examples 1 and 2. [Figure 9] FIG. 10 is a diagram illustrating a distance S in a display device in an arbitrary measurement example. [Figure 10] 10 is a table showing the evaluation results of the texture of images on the display devices of Measurement Examples 3 to 28. [Figure 11] 10 is a table showing the evaluation results of the texture of images of the display devices in Measurement Examples 29 to 38. [Figure 12] 10 is a photograph showing an example of a display device 10 and an electronic device 1 that include, in part of a light-emitting surface 12a, a surface layer 15 whose arithmetic mean roughness Ra, haze value, and distance S of the uneven shape satisfy preferred ranges. [Figure 13] 10 is an enlarged view of a part of a cross section of a surface layer 35 of another embodiment 1. FIG. [Figure 14] 1 is a photograph showing the state of the surface of the laminate 40. [Figure 15] 2 is a diagram illustrating the layer structure of a laminate 70. FIG. DETAILED DESCRIPTION OF THE INVENTION

[0014] Hereinafter, embodiments of the present invention will be described with reference to the drawings, etc. Note that the drawings shown below, including Fig. 1, are schematic diagrams, and the size and shape of each part are appropriately exaggerated to facilitate understanding. The numerical values ​​such as dimensions of each component and the names of materials described in this specification are examples of embodiments, and are not limited to these, and may be selected and used as appropriate. Furthermore, in this specification, terms specifying shapes or geometric conditions, such as parallel and orthogonal, are intended to include not only their strict meanings but also states that perform similar optical functions and have an error that can be considered as parallel or orthogonal.

[0015] (Embodiment) FIG. 1 is a perspective view showing an electronic device 1 of the present embodiment. FIG. 2 is a diagram showing an example of how the electronic device 1 of this embodiment is used. As shown in FIG. 1, the electronic device 1 of this embodiment is a tablet terminal that includes a display device 10 having a display surface 10a (screen) for displaying images, a housing unit 50 that holds the display device 10, an input / output unit and a communication unit (not shown), and a control unit (not shown) that controls the electronic device 1. The input unit is an input device such as a mouse, keyboard, touch panel, or button, and outputs received operation information to the control unit of the electronic device 1. The communication unit is a module for performing communication-related processing. The control unit of the electronic device 1 can send and receive information via a network (not shown) using the communication unit, and can communicate with, for example, a personal computer or the like external to the electronic device 1.

[0016] The electronic device 1 is not limited to the tablet terminal described above, but may also be a smartphone, an e-book reader, a digital photo frame, a display device that displays paintings or NFT (Non-Fungible Token) art, an e-textbook, etc. Note that the electronic device 1 according to the embodiment of the present invention is not limited to these examples.

[0017] 2, the electronic device 1 of this embodiment is embedded in a wall surface 60 formed of a wooden board, for example, and is disposed so that the periphery of the display surface 10a is surrounded by the wooden board, so that the viewer can visually recognize the grain pattern of the wood of the wall surface 60 around the periphery of the display surface 10a. In this embodiment, as an example, the electronic device 1 and the display device 10 display an image in which text or the like is drawn on a wood grain pattern, as shown in Fig. 2. The wood grain pattern of this image is intended to harmonize with the wood grain pattern of the wood on the wall surrounding the display device. Such a display device 10 is used, for example, for in-store sales promotion advertisements and menu displays, and has the advantage of being able to easily change the text information or the like to be displayed. Furthermore, the electronic device 1 and the display device 10 of the present embodiment are described taking as an example a case where the display surface 10a (screen) has a rectangular shape, but the shape of the display surface 10a is not limited to this.

[0018] With conventional general display devices and electronic devices, even if an image with letters or the like drawn on top of a wood grain pattern is displayed, the viewer will perceive it as a flat image displayed on the display surface, making it difficult to achieve harmony with the wood of the surrounding wall surface 60. In contrast, the display device 10 and electronic device 1 of this embodiment allow an observer to perceive the image displayed on the display surface 10a as having the texture of characters and other elements drawn on the surface of wood with a wood grain pattern, thus enabling image display that harmonizes with the surrounding environment. Furthermore, the display device 10 and electronic device 1 can not only display the texture of wood grain on a wooden surface, but also, when displaying objects with uneven surfaces such as stone, paper, oil paintings, textiles, etc., on the display surface 10a, the observer can obtain the texture of the object.

[0019] FIG. 3 is a diagram illustrating the layer structure of the display device 10 of this embodiment. FIG. 4 is a block diagram showing the configuration of the display device 10 of this embodiment. The display device 10 of this embodiment is a transmissive liquid crystal display (liquid crystal display) comprising a backlight 11, a display panel 12, a surface layer 15, a display control unit 20, a storage unit 24, and a sensor unit 25. In Figure 3 and the subsequent figures, for ease of understanding, the direction parallel to the thickness direction of the display device 10 is indicated as the arrow d direction where appropriate. In this d direction, the back side of the display device 10 is the -d side, and the observer side is the +d side.

[0020] The display device 10 illuminates the display panel 12 from the rear side with a backlight 11, and displays image information formed on the display panel 12 on a display surface 10a. In general, depending on the intended use of the display device, the viewing angle tends to be wide horizontally and narrow vertically. In contrast, the display device 10 of this embodiment displays an image in which the viewing angle is equally wide regardless of the direction within the screen, or the change in the viewing angle is small, and the brightness does not change, or the change in brightness is small, regardless of the direction from which it is viewed.

[0021] The backlight 11 is a surface light source device that illuminates the display panel 12 from the rear side (-d side). In this embodiment, the backlight 11 may be an edge-lit surface light source device equipped with a light guide plate or the like, or a direct-lit surface light source device. A general-purpose backlight 11 can be used.

[0022] Known edge-lit backlights include a plurality of LEDs (light-emitting diodes) or the like serving as light sources, and various optical sheets, such as a light guide plate and a reflective film that guide light from the light source, a light diffusion sheet that diffuses light emitted from the light guide plate, a prism sheet that controls the light emission direction, and a reflective polarizing sheet that improves the utilization efficiency of predetermined polarized light. Also known direct-type backlights include a plurality of LEDs or the like arranged on the back side facing the light-emitting surface as light sources, a reflective film, and various optical sheets, such as the light diffusion sheet, prism sheet, and reflective polarizing sheet, as described above.

[0023] The display panel 12 is a plate-shaped component with a highly transparent glass plate as its substrate, and is a transmissive display unit that displays video information on the display surface 10a of the display device 10. Alternatively, the display panel 12 may be a film-shaped component with a highly transparent polyimide film as its substrate. The display panel 12 of this embodiment is a transmissive liquid crystal panel comprising an electrode layer, a polarizing layer, a liquid crystal layer, etc. (not shown). For the liquid crystal layer, it is preferable to employ a driving method with a wide viewing angle range, such as a VA method, IPS method, or FFS method.

[0024] In the display device 10 of this embodiment, a surface layer 15 is laminated on the light-emitting surface 12a of the display panel 12. The display device 10 of this embodiment preferably has a gentle luminance distribution on the light-emitting surface 12a, and exhibits a wide viewing angle characteristic with little or no luminance reduction when viewed from an oblique direction compared to when viewed from the front. Ideally, the display surface 10a of the display device 10 and the electronic device 1 has a gentle Lambertian luminance distribution in both the vertical and horizontal directions of the screen. In the display device 10 of this embodiment, it is preferable that, on the light output surface 12a, when the brightness in the normal direction of the light output surface 12a at point B, which corresponds to point A (see Figure 1) that is the center of the display surface 10a (front brightness, brightness at an observation angle of 0°) is used as a reference, the reduction rate of brightness in the direction that forms an angle of 60° with respect to the normal direction of the light output surface 12a at point B (brightness at an observation angle of 60°) is 45% or less.

[0025] The surface layer 15 is laminated on the light-emitting surface 12a of the display panel 12, and is located closest to the viewer (+d side) in this display device 10. The surface layer 15 may be laminated integrally with the light-emitting surface 12a, or may be bonded to the light-emitting surface 12a via a highly transparent bonding layer (not shown). This bonding layer may have light-diffusing properties. The surface layer 15 is a film-like or sheet-like member that is optically transparent and has a fine, irregular uneven shape on the surface facing the viewer. The surface layer 15 has the function of improving the texture of objects in an image displayed on the display surface of the display device 10. The surface layer 15 is not limited to the texture of wood as in this embodiment, but can also improve the texture of images of objects having fine and irregular uneven shapes on the surface, such as stone, paper, paintings such as oil paintings, cloth, knitted fabric, woven fabric, etc., by being placed on the light-emitting surface 12a.

[0026] FIG. 5 is an enlarged view of a part of the cross section of the surface layer 15 of this embodiment. The surface layer 15 of this embodiment includes a base layer 151 and an uneven layer 152. The surface layer 15 diffuses light emitted from the light-emitting surface 12a of the display panel 12 by its uneven shape, etc. This diffusion effect has no directionality.

[0027] The base layer 151 is a light-transmitting sheet- or film-shaped resin member. Suitable resins for forming the base layer 151 include thermoplastic resins such as PC (polycarbonate), MBS (methacrylate-butadiene-styrene copolymer), MS (methacrylate-styrene copolymer), PET (polyethylene terephthalate), PS (polystyrene), and TAC (triacetyl cellulose), but are not limited thereto, and other resins may also be used. The thickness of the base material layer 151 is preferably 20 to 100 μm, and more preferably 30 to 50 μm.

[0028] The uneven layer 152 is formed on the viewer-side (+d side) surface of the base layer 151 in the thickness direction (d direction), and has fine irregular unevenness on the viewer-side surface. The uneven layer 152 is integrally formed on one side of the base layer 151. The concave-convex layer 152 is formed of an ultraviolet curable resin such as urethane acrylate, polyester acrylate, epoxy acrylate, etc. Alternatively, the concave-convex layer 152 may be formed of other ionizing radiation curable resins such as electron beam curable resins.

[0029] The uneven shape of the uneven layer 152 is preferably one in which the size of the unevenness (height of the convex portions, depth of the concave portions) and the distribution of the positions of the unevenness are irregular, but the uneven shape may also have periodicity, etc., depending on the object of the displayed image. The uneven shape can be formed by applying an ultraviolet-curable resin or the like to one side of the base layer 151, pressing a mold for forming the uneven shape onto the coating to form (transfer) the uneven shape, and irradiating ultraviolet light to harden the ultraviolet-curable resin. The method for forming the uneven layer 152 is not limited to the above method and may be selected as appropriate. The mold for forming the uneven shape may be formed by taking a mold from the surface of an object (in this embodiment, the surface of a wooden board) whose texture is to be improved when displayed as an image, to form a reverse mold of the uneven shape.

[0030] Furthermore, the uneven shape of the surface layer 15 may be set to a preferred cross-sectional shape of unevenness depending on the object in the image displayed on the display surface 10a, and the angle of the unevenness and the sharpness of the tops of the protrusions can be set as appropriate. From the viewpoint of enhancing the texture of an object displayed as an image, the uneven shape preferably has an arithmetic mean roughness Ra (JIS B 0601:2001) of 10 μm or more and 3000 μm or less. If the arithmetic mean roughness Ra of the uneven shape is less than 10 μm, the unevenness of the uneven shape will be small, the surface of the surface layer 15 will be nearly flat, and the image light will not be sufficiently diffused, making it impossible to improve the texture. On the other hand, if the arithmetic mean roughness Ra of the uneven shape is greater than 3000 μm, the unevenness of the uneven shape will be too large, resulting in significant blurring of the image and making it impossible to improve the texture. Therefore, it is preferable that the arithmetic mean roughness Ra of the uneven shape be within the above range. The arithmetic mean roughness Ra of the uneven shape can be measured using a laser microscope (VK-9710 manufactured by Keyence Corporation) or the like.

[0031] Furthermore, by ensuring that the arithmetic mean roughness Ra of the uneven surface meets the above-mentioned preferred range, the surface layer 15 can improve the texture of the object displayed as an image (such as wood, stone, paper, textiles, or paintings). However, the optimal range for the arithmetic mean roughness Ra varies depending on the object whose texture you wish to improve.

[0032] Furthermore, from the viewpoint of expressing texture, it is preferable that the haze value of the surface layer 15 is 40% or more and 85% or less. If the haze value of the surface layer 15 is less than 40%, the texture of the object displayed as an image will be reduced. If the haze value of the surface layer 15 is more than 85%, the image will be blurred and the image resolution will be reduced. Therefore, it is preferable that the haze value of the surface layer 15 is within the above range. This haze value conforms to JIS K 7136:2000 and can be measured using a haze meter (HM-150, manufactured by Murakami Color Technology Laboratory Co., Ltd.). During measurement, parallel light is incident at an incident angle of 0° from the side of the surface layer 15 that does not have an uneven shape (the side of the base layer 151).

[0033] The surface layer 15 is not limited to the above example, and may have the following forms. The uneven layer 152 of the surface layer 15 or the base layer 151, or both of them, may contain particles that act as a diffusing material for diffusing light. The surface layer 15 may have a single layer structure without the base layer 151 . The surface layer 15 may also have an antireflection layer formed on its outermost surface along the fine uneven shape. The surface layer 15 may also have a layer having at least one of the following functions: ultraviolet absorption, antistatic, antifouling, hard coating, etc.

[0034] In addition, in the thickness direction (direction d) of the display panel 12, it is preferable that the distance S from the bottom of the uneven shape of the surface layer 15 on the rear side to the surface of the image forming layer that forms the image in the display panel 12 closest to the viewer be 0.3 mm or less, from the viewpoint of improving the texture of the image. The image forming layer is a liquid crystal layer when the display panel 12 is a liquid crystal display panel as in this embodiment. Therefore, in this embodiment, the distance S can be adjusted by changing the thickness of a member (i.e., a CF substrate, a polarizing layer, etc., not shown) located between the liquid crystal layer of the display panel 12 and the surface layer 15.

[0035] If the distance S is greater than 0.3 mm, the image will appear to be positioned inside the display panel 12 rather than on the outermost surface of the display device 10, which is the display surface, creating a sense of depth in the image and degrading the texture of the image. Therefore, it is preferable that the distance S be 0.3 mm or less.

[0036] The display control unit 20 and other components will be described with reference to FIG. The sensor unit 25 detects the brightness and color of the light in the operating environment of the electronic device 1 and the display device 10, that is, the brightness and color of the ambient light incident on the display surface 10a, and outputs this to the image adjustment unit 21. In this embodiment, an example will be given in which the sensor unit 25 detects the brightness and color of ambient light such as sunlight or illumination light incident on point A, which is the center of the display surface 10a of the display device 10, and outputs this to the image adjustment unit 21 of the display control unit 20. This sensor unit 25 may be, for example, a general-purpose spectrophotometer arranged outside the display device 10, or a smaller ambient light sensor that outputs color information (chromaticity) using the tristimulus colors XYZ of the CIE XYZ color system, or a light-receiving element arranged within the display panel 12.

[0037] The sensor unit 25 is not limited to the example described above; it may also be configured to detect the brightness and color of ambient light at multiple points on the display surface 10a. In this case, the display surface 10a may be divided into multiple regions, and the sensor unit 25 may detect the brightness and color of ambient light at the center of each region. For example, the display surface 10a may be divided into multiple regions, and a light-receiving element, which will be the sensor unit 25, may be placed at the center of each region within the display panel 12. Furthermore, when a light-receiving element is placed within the display panel 12 as the sensor unit 25, for example, the light-receiving element may be placed near the pixel electrode in a single pixel circuit. In this case, it may be provided in all pixel circuits in the area that becomes the display surface 10a, or it may be placed only in a selected number of locations. A photodiode or the like can be used as the light-receiving element.

[0038] The display control unit 20 controls the driving of the backlight 11 and the display panel 12. The display control unit 20 has an image adjustment unit 21, an electrode control unit 22, a light source control unit 23, etc. The display control unit 20 can use a CPU (Central Processing Unit) or the like. The image adjustment unit 21 adjusts the brightness and color tone of the image to be displayed on the display surface 10 a of the display device 10 based on the brightness and color of the external light detected by the sensor unit 25 . When the sensor unit 25 detects the brightness and color of external light at one point on the display surface 10a, the image adjustment unit 21 adjusts the brightness and color of the entire image displayed on the screen based on the information on the detected brightness and color of the external light. Also, when the sensor unit 25 detects the brightness and color of external light at multiple points on the display surface 10a, the image adjustment unit 21 may adjust the brightness and color of the image to be displayed based on the two-dimensional distribution of the brightness and color of the external light on the display surface 10a. In particular, when the sensor unit 25 is arranged in each pixel, the image adjustment unit 21 may adjust the brightness and color of the image in each pixel area.

[0039] The electrode control unit 22 controls the voltage applied to the electrodes that drive the liquid crystal layer (not shown) of the display panel 12 according to instructions from the image adjustment unit 21 . The light source control unit 23 controls the brightness of the light source (not shown) of the backlight 11 according to instructions from the image adjustment unit 21 .

[0040] The storage unit 24 stores computer programs or data that define processing procedures and the like for the image adjustment unit 21 to adjust the brightness and color tone of the image displayed on the display surface 10a. The storage unit 24 also temporarily stores data and the like necessary for the image adjustment unit 21 and the like to execute processing. The storage unit 24 can use memory elements such as a ROM (Read Only Memory) or a RAM (Random Access Memory). The display control unit 20 of this embodiment can input information and the like via an input unit or a communication unit of the electronic device 1. Note that the present invention is not limited to this example, and the display device 10 may also be provided with an input unit or a communication unit.

[0041] Image display by the electronic device 1 and the display device 10 of this embodiment will be described with reference to FIG. First, an image to be displayed on the display surface 10a is output to the display control unit 20 by the input unit and communication unit of the electronic device 1, and an instruction to display the image is given to the display control unit 20 of the display device 10. For example, in this embodiment, an image in which text is drawn on the surface of wood with a wood grain pattern is selected, as shown in Fig. 2.

[0042] Next, image adjustment unit 21 instructs sensor unit 25 to detect the brightness and other aspects of external light. Sensor unit 25 detects the brightness and color of external light incident on display surface 10a. In this embodiment, sensor unit 25 detects the brightness and color of external light incident on point A, which is the geometric center of display surface 10a. Sensor unit 25 outputs the detection result to image adjustment unit 21. Image adjustment unit 21 adjusts the brightness and color of the image to be displayed according to the brightness and color of the external light detected by sensor unit 25. Specifically, image adjustment unit 21 calls up a program related to image processing from storage unit 24, and calculates, based on the program, the brightness and color of wood and characters corresponding to the external light environment detected by sensor unit 25. Then, image adjustment unit 21 generates an image (hereinafter referred to as an adjusted image) with adjusted brightness and color according to the calculation result.

[0043] Next, the image adjustment unit 21 outputs information necessary for driving the electrodes of the display panel 12 and the light source of the backlight 11 to the electrode control unit 22 of the display panel 12 and the light source control unit 23 of the backlight 11, based on the adjusted image. As a result, the display device 10 displays the adjusted image on the display surface 10a.

[0044] In this case, as described above, the surface layer 15 of this embodiment has the effect of allowing the viewer to perceive the texture of images of wood, stone, paper, paintings, textiles, etc. displayed on the screen, and enhancing that texture. Furthermore, the sensor unit 25 and the image adjustment unit 21 of the display control unit 20 allow the display device 10 to display an image that corresponds to the brightness and color of the external light in the environment in which the display device 10 is placed, thereby further enhancing harmony between the image and the surrounding environment. As a result, the display device 10 and the electronic device 1 can display images that harmonize with the surrounding environment and have an improved texture, thereby improving design.

[0045] (Evaluation of image texture using display devices for measurement examples 1-38) Display devices of Measurement Examples 1 to 38, which correspond to examples and comparative examples of the display device 10 of this embodiment, were prepared, and the textures displayed on the display surfaces, etc. were evaluated. The display devices of Measurement Examples 1 to 38 differ in the luminance distribution on the light-emitting surface 12a of the display panel 12, the arithmetic mean roughness Ra of the uneven shape of the surface layer 15, the distance S from the bottom of the uneven shape of the surface layer 15 to the liquid crystal layer serving as the image-forming layer, the haze value of the surface layer 15, etc.

[0046] (Brightness distribution on the light output surface of the display panel) First, display devices of measurement examples 1 and 2, which have different luminance distributions of emitted light on the light output surface 12a of the display panel 12, were prepared, and the appearance of the images was evaluated. The luminance distribution of the emitted light on the light-emitting surface 12a of the display panel 12 is the luminance distribution at point B, which is the center of the light-emitting surface 12a. In the display devices of Measurement Examples 1 and 2, as an example, measurements were taken along the light-emitting surface 12a in a direction corresponding to the left-right direction of the screen when the display device is in use (for example, a direction parallel to the long side of the display surface 10a in FIG. 2). This point B coincides with point A on the display surface 10a when viewed from the thickness direction of the display device. Note that in both the display devices of Measurement Examples 1 and 2, the luminance distribution in a direction passing through point B on the light-emitting surface 12a and parallel to the up-down direction of the screen is equal to the luminance distribution in a direction passing through point B and parallel to the left-right direction of the screen, or the difference is so small that it can be considered equal.

[0047] FIG. 6 is a diagram showing the configuration of the display device of Measurement Example 1. As shown in FIG. FIG. 7 is a diagram showing the configuration of the display device of Measurement Example 2. As shown in FIG. The display device of Measurement Example 1 includes a surface layer 15, a display panel 12, and a backlight 11B, as shown in Fig. 6. The display device of Measurement Example 2 includes a surface layer 15, a display panel 12, and a backlight 11, as shown in Fig. 7. The display device of Measurement Example 1 and the display device of Measurement Example 2 have some differences in the optical members constituting the backlight, but are otherwise similar in configuration. The display device of Measurement Example 1 corresponds to a commercially available display device (PV10109LZR40G manufactured by Kingtech) with a surface layer 15 laminated on the outermost surface.

[0048] The display devices in measurement examples 1 and 2 both have a screen size of 10.1 inches. The display panel 12 used in the display devices of Measurement Examples 1 and 2 includes, in order from the rear side (backlight side) in the thickness direction, a polarizing layer 121, a TFT substrate 122, a liquid crystal layer 123, a CF substrate 124, an optical film (retardation film) 125, and a polarizing layer 126. This display panel 12 is an IPS-type liquid crystal display panel.

[0049] The backlight 11B of the display device of measurement example 1 includes a light source section 111, a light guide plate 112, a reflector plate 113, a light diffusion sheet 114, a first prism sheet 115, and a second prism sheet . The backlight 11 of the display device of measurement example 2 includes a light source unit 111 , a light guide plate 112 , a reflector 113 , a light diffusion sheet 114 , and a Lambertian light diffusion plate 117 .

[0050] The light source section 111 is a member that emits light, and a plurality of LEDs are arranged at equal intervals along the side surface (light incident surface 112a) of the light guide plate 112. The light guide plate 112 is a member that guides light from the light source unit 111 toward a side surface 112b opposite to the light incident surface 112a. The reflector plate 113 is a member that reflects light that has been emitted from the light guide plate 112 toward the rear surface side back toward the light guide plate 112. The light diffusion sheet 114 is an optical member that has the effect of diffusing and spreading the light emitted from the light guide plate 112, and has a non-directional diffusion effect.

[0051] The first prism sheet 115 and the second prism sheet 116 used in the backlight 11B of measurement example 1 are optical sheets with a plurality of unit prisms arranged on the viewer-side (+d-side) surface, and have the function of directing light emitted from the light diffusion sheet 114 toward the front using the unit prisms. The unit prisms extend in one direction along the sheet surface, have an isosceles triangular cross-sectional shape, and are arranged in a direction intersecting the longitudinal direction. When viewed from the thickness direction of the display device, the arrangement directions of the unit prisms of the first prism sheet 115 and the second prism sheet 116 are perpendicular to each other. In this embodiment, the arrangement direction of the unit prisms of the first prism sheet 115 is the vertical direction of the screen, and the arrangement direction of the unit prisms of the second prism sheet 116 is the horizontal direction of the screen.

[0052] The Lambertian light diffusion plate 117 used in the backlight 11 of Measurement Example 2 is an optical sheet that diffuses incident parallel light and emits it, and is a diffusion sheet that causes the luminance distribution of the emitted light to become a Lambertian distribution. Here, a diffuse transmission sheet (Zenith Polymer Lambertian Diffuse Transmission Sheet SG3201 manufactured by SphereOptics) was used as the Lambertian light diffusion plate 117.

[0053] The luminance distribution of the display device in each measurement example was measured by displaying a white screen on the display device in each measurement example and using a conoscope manufactured by Autoronics, at point B on the light output surface 12a, from -80° to 80° in the left and right directions of the screen.

[0054] FIG. 8 is a graph showing the luminance distribution on the light output surface 12a of the display panel 12 of the display devices of Measurement Examples 1 and 2. In FIG. In the graph shown in Fig. 8, the vertical axis represents normalized luminance, and the horizontal axis represents the observation angle (angle relative to the normal direction of the screen). In the graph shown in Fig. 8, for the display devices of Measurement Examples 1 and 2, the front luminance is set to 1 as the reference, and the luminance at each observation angle is normalized. As shown in Figure 8, in the display device of Measurement Example 1, the luminance decreases as the observation angle increases, with the half angle being around 25 degrees. In contrast, in the display device of Measurement Example 2, the decrease in luminance is small even when the observation angle increases.

[0055] In Measurement Example 1, the display device shows a decrease in brightness at an observation angle of 60° relative to the brightness at an observation angle of 0° (front brightness), which is approximately 83.3%. On the other hand, in Measurement Example 2, the display device shows a decrease in brightness at an observation angle of 60° relative to the brightness at an observation angle of 0° (front brightness), which is approximately 43.6%. This brightness decrease rate is the average of the decrease rate at an observation angle of +60° and the decrease rate at an observation angle of -60°.

[0056] In the display devices of measurement examples 1 and 2, with the surface layer 15 placed on the light output surface 12a of the display panel 12, an image of the same wood grain pattern on the screen was actually displayed, and the appearance and texture of the image were evaluated. The surface layer 15 used in the display devices of Measurement Examples 1 and 2 has an arithmetic mean roughness Ra of the uneven shape of 100 μm and a haze value of 60%. The display devices of measurement examples 1 and 2 used a spectroradiometer CL-500A manufactured by Konica Minolta, Inc. as the sensor unit 25 to measure the brightness and color of external light at point A, which is the center of the display surface 10a, and the display control unit 20 adjusted the brightness and color of the image, and displayed the adjusted image on the display surface 10a.

[0057] In evaluating the texture of the displayed image, the brightness of the external light incident on point A on the display surface 10a was 100 lx, and its color was measured using the sensor unit 25 (Konica Minolta CL-500A spectroradiometer) with x=0.303826 and y=0.329804 on the CIE chromaticity diagram.

[0058] The texture of the displayed image was evaluated in a bright room environment, with the observer observing from a position 30 cm away from point A, the center of the screen, in a direction 60 degrees to the normal direction of the display surface 10a (observation angle 60 degrees).

[0059] The evaluation of the texture of the image displayed on the display surface 10a of the display device in Measurement Examples 1 and 2 is as follows. In the display device of Measurement Example 1, the brightness of the image decreased significantly as the observation angle increased, and the change in image brightness due to the observation angle was rapid. Therefore, in the display device of Measurement Example 1, it was difficult for the viewer to grasp the texture of the wood surface in the displayed image.

[0060] On the other hand, with the display device of Measurement Example 2, the change in image brightness due to the viewing angle was small, and the image could be observed regardless of the viewing angle. In addition, the viewer could fully grasp the texture of the wood surface from the displayed image they viewed, and they could also recognize the letters as being drawn on a wooden board.

[0061] In addition, when the display device of measurement example 2 was observed with part of the surface layer 15 removed, reflections of external light, etc. were visible in the areas without the surface layer 15, and the flat surface of the display surface was visible, making it difficult to recognize the texture of wood grain.

[0062] (Regarding the arithmetic mean roughness Ra and distance S of the uneven shape) Next, display devices of measurement examples 3 to 28 were prepared which differed in the arithmetic mean roughness Ra of the uneven shape of the surface layer 15 and the distance S between the lowest point of the uneven shape (the point closest to the rear side (-d side) of the uneven shape) and the point closest to the viewer side (+d side) of the liquid crystal layer 123, and the texture of the images displayed on these display surfaces 10a was evaluated.

[0063] The display devices of measurement examples 3 to 28 have the same display panel 12 and backlight 11 as in measurement example 2, but the distance S and arithmetic mean roughness Ra are different. In this evaluation, the display device of each measurement example detected the brightness and color of external light at point A on the display surface 10a using the sensor unit 25, and displayed an image whose brightness and color were adjusted by the display control unit 20. The observation position and external light conditions for the displayed image of the display device of each measurement example were as described above.

[0064] Fig. 9 is a diagram for explaining the distance S in a display device of an arbitrary measurement example. Fig. 9 shows an enlarged view of a part of a cross section parallel to the thickness direction (direction d) of the display device of an arbitrary measurement example. 9, in the display devices of Measurement Examples 3 to 28, the distance S is the distance from the bottom of the concave-convex shape of the surface layer 15 on the rearmost side to the surface of the liquid crystal layer 123 on the viewer's side. This distance S can be adjusted by changing the thicknesses of the members between the liquid crystal layer 123 and the surface layer 15, that is, the CF substrate 124, the optical sheet 125, and the polarizing layer 126.

[0065] Furthermore, five examples of arithmetic mean roughness Ra of the surface layer 15 were prepared: 5 μm, 8 μm, 10 μm, 3000 μm, and 7000 μm. In addition, six examples of distance S were prepared: 0.15 mm, 0.20 mm, 0.25 mm, 0.3 mm, 0.5 mm, and 0.7 mm. Furthermore, in the display devices of these measurement examples 3 to 28, the uneven surface layer 152 contains a light-diffusing material (Micropearl, manufactured by Sekisui Chemical Co., Ltd., with an average particle size of 10 μm), and the surface layer 15 is adjusted so that the haze value is approximately 60%, regardless of the arithmetic mean roughness Ra of the uneven surface.

[0066] FIG. 10 is a table showing the evaluation results of the texture of images on the display devices of measurement examples 3 to 28. In the "Texture Evaluation" section of the table shown in Figure 10, images where the observer visually perceived the texture are marked with a circle (○) for good quality, and images where the texture was difficult to perceive are marked with a cross (×) for poor quality. As shown in the table in Fig. 10, the larger the arithmetic mean roughness Ra of the uneven shape, the more blurred the image became, and the texture of the object could not be perceived. Also, when the arithmetic mean roughness Ra of the uneven shape of surface layer 15 was 5 µm or 8 µm, which is less than 10 µm, the uneven shape was too small, and the roughness of the surface of the object displayed in the image was not visible, so the viewer could not perceive the texture of the image.

[0067] Furthermore, as the distance S increased, the sense of depth in the image (the feeling that the image is displayed inside the display panel 12, i.e., behind the screen) increased, making it difficult to obtain a sense of the object's texture. For example, when the distance S was 0.3 mm or smaller values ​​of 0.25 mm, 0.20 mm, and 0.15 mm, and the arithmetic mean roughness Ra of the uneven shape was 10 μm or 3000 μm, the sense of depth was suppressed and the texture of the image was obtained. However, when the arithmetic mean roughness Ra was 7000 μm, regardless of the value of the distance S, the image became blurred and it was difficult to obtain the texture of the image.

[0068] From the above, it can be seen that by setting the arithmetic mean roughness Ra of the surface layer 15 to 10 μm or more and 3000 μm or less, the texture of objects in the image can be improved. Furthermore, by setting the distance S to 0.3 mm or less, the sense of depth in the image can be suppressed and the texture of objects in the image can be improved.

[0069] (Regarding the haze value of surface layer 15) Next, display devices of Measurement Examples 29 to 38, which have different haze values ​​of the surface layer 15 and different arithmetic mean roughness of the uneven shape, were prepared, and the texture of the images was evaluated in the same manner. The display devices in measurement examples 29-38 have the same display panel 12 and backlight 11 as in measurement example 2, but differ in the haze value of the surface layer 15 and the arithmetic mean roughness Ra of the uneven surface. Also, the display devices in measurement examples 29-38 share the common feature of having a distance S of 0.25 mm.

[0070] The display devices in measurement examples 29-33 share the common feature of having an arithmetic mean roughness Ra of 10 μm, but their haze values ​​differ, being 90%, 85%, 60%, 40%, and 25% respectively. The display devices in measurement examples 34-38 share the common feature of having an arithmetic mean roughness Ra of 3000 μm, but their haze values ​​differ, being 90%, 85%, 60%, 40%, and 25% respectively. In the display devices of measurement examples 29 to 38, the uneven surface layer 152 of the surface layer 15 contains a light-diffusing material (Micropearl, manufactured by Sekisui Chemical Co., Ltd., with an average particle size of 10 μm), and the haze value of the surface layer 15 is adjusted by adjusting the amount of this material.

[0071] In this evaluation, the display device of each measurement example detected the brightness and color of external light at point A on the display surface 10a using the sensor unit 25, and displayed an image whose brightness and color were adjusted by the display control unit 20. The observation position and external light conditions for the displayed image of the display device of each measurement example were as described above.

[0072] Figure 11 is a table showing the evaluation results of the image texture of the display devices for measurement examples 29 to 38. In the "Texture Evaluation" section of the table shown in Figure 11, images where the observer visually perceived sufficient texture were marked with ◎ (Excellent), and images where texture was present but inferior to those marked with ○ (Good). The observer's position relative to the display surface 10a and the surrounding ambient light during the evaluation were as described above. As shown in the table of FIG. 11, it was found that the larger the arithmetic mean roughness Ra of the uneven shape of the surface layer 15, the higher the haze value required to obtain the texture of an object. For example, if the arithmetic mean roughness Ra of the surface layer 15's uneven surface is 3000 μm, then a texture can be obtained for objects in the displayed image if the haze value of the surface layer 15 is between 40% and 85%, and a higher texture can be obtained, especially when the haze value of the surface layer 15 is 85%. In contrast, if the arithmetic mean roughness Ra of the surface layer 15's uneven surface is 10 μm, a high texture can be obtained even with a haze value of 40%.

[0073] When the haze value of surface layer 15 was less than 40%, the transparency of surface layer 15 increased, resulting in a greater sense of depth in the image, and the image quality deteriorated compared to when the haze value of surface layer 15 was between 40% and 85%. Conversely, when the haze value of surface layer 15 was greater than 85%, the sense of depth in the image decreased, but the image blurring became too great compared to when the haze value of surface layer 15 was between 40% and 85%, making the image more difficult for the observer to perceive and reducing the texture of the objects. Therefore, it is preferable that the haze value of the surface layer 15 be between 40% and 85%.

[0074] Based on the above, in order for an observer to obtain a sense of texture from the image displayed on the display surface 10a, it is preferable to use a display device 10 and an electronic device 1 equipped therewith that satisfy the following conditions. Preferably, display device 10 includes a surface layer 15 having an irregularly shaped configuration facing the viewer at a position closest to the viewer (+d side), the arithmetic mean roughness Ra of the irregular configuration being 10 μm to 3000 μm, the haze value of surface layer 15 being 40% to 85%, the distance S from the rearmost bottom of the irregular configuration to the viewer-side surface of the image-forming layer (in this embodiment, the liquid crystal layer) being 0.3 mm or less in the thickness direction of display device 10, and the decrease in luminance at an observation angle of 60° relative to the luminance at an observation angle of 0° (front luminance) on the surface on which surface layer 15 is laminated (in this embodiment, the light-emitting surface of display panel 12) is 45% or less. Display device 10 also preferably includes a sensor unit 25 that detects the brightness and color of external light incident on display surface 10a, and an image adjustment unit 21 that adjusts the brightness and color of the image displayed by display device 10 based on the brightness and color information of the external light detected by sensor unit 25. As a result, the display device 10 can display an image whose brightness and color correspond to the brightness and color of the ambient light, and which also provides a realistic texture of the objects depicted in the image.

[0075] Figure 12 is a photograph showing an embodiment of a display device 10 and electronic device 1, which have a surface layer 15 on a part of the light-emitting surface 12a that satisfies a preferred range for the arithmetic mean roughness Ra of the uneven shape, the haze value, and the distance S. The display device 10 and electronic device 1 of this example shown in FIG. 12 use the backlight 11 and display panel 12 used in the display device of Measurement Example 2, and FIG. 12 shows a state in which a surface layer 15 is disposed on a portion of the light-emitting surface 12a. At this time, the brightness and color of the displayed image are adjusted by the sensor unit 25, image adjustment unit 21, etc. The image displayed on the display surface of the display device 10 of the example is an image of the word "Kepler" written in whitish-brown paint on a brown wood grain pattern, and the surface layer 15 is disposed in the area where the characters are displayed. The photograph shown in FIG. 12 was taken in an indoor white light lighting environment (100 lx) from a direction 60° relative to the normal direction of the light-emitting surface 12a.

[0076] The surface layer 15 shown in Fig. 12 has a haze value of 50% and an arithmetic mean roughness of the uneven shape of 100 μm. In addition, the display device 10 of the example shown in Fig. 12 has a distance S of 0.3 mm, and the reduction rate of brightness at an observation angle of 60° is 43.65% when the brightness at an observation angle of 0° is used as the reference.

[0077] 12, in the area where the surface layer 15 was not placed, the observer could see the smoothness of the light-emitting surface 12a, which serves as the display surface, due to the reflection of the illumination light, etc., and the texture of wood was not obtained. However, in the area where the surface layer 15 was placed, the texture of wood was greatly improved, and it was observed that the letters were written on the wood grain pattern of the wood.

[0078] (Another embodiment 1) The texture of the surface layer 15 can be further improved by adjusting the angle of the inclined surfaces of the texture and the distribution of the texture in accordance with the texture of the surface of an object (wood grain, paper, textile, stone, etc.) whose texture is to be improved, and also by adjusting the distribution of the haze value on the outermost surface of the texture. That is, from the viewpoint of further improving the texture, it is preferable to adjust the two-dimensional distribution of the haze value in accordance with the texture when the surface layer is viewed in plan.

[0079] Fig. 13 is an enlarged view of a part of the cross section of the surface layer 35 of Alternative Embodiment 1. Fig. 13 shows an enlarged view of a part of the cross section parallel to the thickness direction of the surface layer 35. The surface layer 35 of this other embodiment 1 is disposed on the light-emitting surface 12a of the display panel 12, similar to the surface layer 15 of the previously described embodiment. The surface layer 35 includes a base layer 151 and an uneven layer 352. The base layer 151 is similar to the base layer 151 of the surface layer 15 of the previously described embodiment. The uneven layer 352 is similar to the uneven layer 152 of the previously described embodiment, but differs in the distribution of the haze value at the outermost surface of the uneven shape.

[0080] The surface layer 35 has a non-uniform distribution of haze values ​​in its surface direction. Specifically, the haze value at the outermost surface of the uneven shape of the surface layer 35 has a non-uniform secondary distribution in the surface direction of the surface layer 35. This non-uniform distribution of haze values ​​follows the unevenness of the irregular uneven shape. Furthermore, on the outermost surface of the uneven shape, the haze value of the convex portions 352a is smaller than the haze value of the concave portions 352b. Furthermore, the concave and convex shape of the surface layer 35 has a plurality of convex portions 352a and concave portions 352b, and the haze value on the surface of each convex portion 352a and each concave portion 352b is different. Therefore, when the surface layer 35 is viewed in plan, the haze value of the surface layer 35 has a two-dimensional distribution in the surface direction of the surface layer 35 corresponding to the distribution of the concave and convex shape, and the value is distributed non-uniformly. In the surface layer 35 of this other embodiment 1, the uneven layer 352 has an uneven shape that imitates wood grain, and further, the haze value on the surface of the convex portions 352a is smaller than the haze value on the surface of the concave portions 352b.

[0081] By forming the surface layer 35 in this form, when external light such as sunlight or illumination light is irradiated onto the surface layer 35, the specular reflectance of the areas that become the convex portions 352a of the uneven shape is high, and the specular reflectance of the areas that become the concave portions 352b is low. As a result, when a viewer views the display surface of the display device from a direction that specularly reflects external light, the areas corresponding to the convex portions 352a appear brighter than the areas corresponding to the concave portions 352b, allowing the viewer to see the uneven shape more clearly. This allows the viewer to more clearly perceive the texture of the object displayed on the display surface.

[0082] The haze value on the outermost surface of the uneven shape can be imparted by, for example, applying resin 354 containing particles 353 having a particle size smaller than that of the uneven shape to the surface of the uneven shape. In addition, by controlling the amount of particles 353 to be applied in accordance with the uneven shape, the two-dimensional distribution of the haze value in the plane direction of surface layer 35 can be controlled.

[0083] Plastic beads are suitable for such particles 353, and examples thereof include styrene beads, melamine beads, acrylic beads, acrylic-styrene beads, polycarbonate beads, and polyethylene beads. Furthermore, particles 353 and resin 354 containing them preferably have optical transparency. Furthermore, plastic beads used as particles 353 preferably have hydrophobic groups on their surfaces. The refractive index ratio between the particles 353 and the resin 354 (refractive index of particles 353 / refractive index of resin 354) is preferably 1.0 to 1.1.

[0084] As shown in FIG. 13, the particles 353 may be coated with the resin 354, or part of the particles 353 may protrude from the layer of the resin 354. Two or more types of particles may be used as the particles 353. For example, when two types of particles are used, it is preferable to use particles that differ in one or more of the average particle size, shape, material, refractive index ratio with respect to the resin 354, etc. In this configuration as well, it is preferable that the total haze value of the surface layer 35 be within the range of 40% to 85%.

[0085] (Evaluation regarding the presence or absence of a distribution in haze values) Sample A, an example of a surface layer 35 in which the haze values ​​of the surface of the convex portion 352a and the surface of the concave portion 352b of the uneven shape are different, and Sample B, an example of a surface layer 15 in which there is no such difference in haze values, were prepared, and the actual visible texture was evaluated. Sample B has an uneven surface, but does not have a distribution of haze values ​​corresponding to the uneven surface. Sample A has an uneven surface similar to that of Sample B, and further has resin 354 containing particles 353 applied to the outermost surface of the uneven surface, and the haze value of the surface of convex portions 352a of the uneven surface is smaller than the haze value of the surface of concave portions 352b. Samples A and B both have a textured surface that mimics wood grain patterns, and have the effect of enhancing the texture of wood grain in images.

[0086] The texture was evaluated under the following conditions. Two linear polarizing plates were stacked on a transparent glass plate so that their polarization directions were orthogonal, and samples A and B were placed adjacently on top of the two linear polarizing plates to create a laminate 40. This laminate 40 was irradiated with external illumination light, and an observer observed and evaluated the texture of the areas where samples A and B were provided. When irradiated with illumination light, the illuminance at the center of the surface of laminate 40 was 100 lx.

[0087] Figure 14 is a photograph showing the surface of the laminate 40. In Figure 14, the primary ambient light source, the illumination light, is incident on the surface of the laminate 40 at an incident angle of 40 degrees, and Figure 14 shows the view from the direction of specular reflection of that illumination light. In the region 403, where two linear polarizing plates are laminated on a glass plate and no surface layer is provided, the two polarizing plates are arranged orthogonally, so it appears black, but as shown in Figure 14, it appears whitish due to the reflection of illumination light.

[0088] In an area 402 on which two linear polarizing plates are laminated on a glass plate and in which sample B corresponding to an example of surface layer 15 is provided, reflection of illumination light is suppressed and the area appears darker than in an area 403 in which no surface layer is provided. In addition, in the area 402 in which sample B is provided, a wood grain pattern due to the uneven shape is visible, and the texture of wood grain is obtained, but part of the external light is uniformly reflected specularly by the uneven surface, and the area appears slightly brighter than an area 401 described below.

[0089] In contrast, in region 401, where two linear polarizers are laminated on the glass plate and where sample A, which corresponds to the example of surface layer 35, is provided, the light diffusing effect of particles 353 provided on the outermost surface of the uneven shape enhances the matte texture resembling that of a wood surface. Furthermore, in this region 401, convex portions 352a appear bright and concave portions 352b appear dark, and the brightness changes along the wood grain pattern, reproducing the wood grain texture to a higher degree. Therefore, region A, where sample A is provided, has a more pronounced wood grain texture than region 402, where sample B is provided.

[0090] For the above reasons, it is preferable that the haze value at the outermost surface of the uneven shape of the surface layer 35 is not distributed uniformly in the plane direction of the surface layer 35. Furthermore, it is preferable that the haze value of the convex portions 352a at the outermost surface of the uneven shape of the surface layer 35 is smaller than the haze value of the concave portions 352b.

[0091] (Another embodiment 2) Furthermore, in a liquid crystal display device such as the display device 10 of this embodiment, when external light is incident on the display panel 12 used for image display, some of the external light is reflected not only from the outermost surface of the display panel 12 but also from within the display panel 12. When this reflected light reaches the viewer, it is perceived as glare, degrading the texture of the object displayed on the display surface 10a. Therefore, it is desirable that the reflectance of external light within the display device 10, and in the display device 10 of this embodiment, the specular reflectance of external light within the display panel 12, is 1% or less.

[0092] Such a display panel 12 can be realized, for example, by using a circular polarizer on the viewer's side of the liquid crystal layer instead of a conventional polarizer provided on the viewer's side of the liquid crystal layer. By using the display device according to the second alternative embodiment as described above, a viewer who views an image of an object displayed on the display screen can get a stronger sense of the texture of the object.

[0093] (Evaluation of the reflectance of external light inside the display device) The following laminate 70 was prepared, and the effect of improving the texture of the surface layer was evaluated based on the reflectance of external light inside the display device. Fig. 15 is a diagram illustrating the layer structure of the laminate 70. In Fig. 15, for ease of understanding, the diffusion, refraction, etc. of external light L are omitted. The laminate 70 is formed by laminating two linear polarizing plates 72 and 73 on a mirror 71, and then placing a surface layer 15 on top of them. The surface layer 15 has an uneven shape suitable for reproducing a wood grain pattern and has the function of improving the texture of the wood grain pattern. The crossing angle of the polarization directions of the two linear polarizing plates 72 and 73 can be adjusted, which allows the regular reflectance of external light within the laminate 70 to be adjusted. External light L (illumination light) is irradiated so as to be incident at an incident angle of 60 degrees relative to the surface direction of the surface layer 15 of this laminate 70. The illuminance at the center of the surface of the surface layer 15 is 100 lx.

[0094] The specular reflectance of external light was measured using a spectroradiometer (SR-UL1 manufactured by Topcon Technohouse Corporation) with the surface layer 15 removed from the laminate 70. Specifically, measurement light was incident on the surface of the linear polarizer 73 at an incident angle of 5 degrees, and the spectroradiometer measured the reflected light that was specularly reflected at a reflection angle of 5 degrees, and the specular reflectance was calculated. In addition, an observer observed and evaluated the texture from a direction at an angle of 60 degrees relative to the normal to the plane direction of the surface layer 15.

[0095] When the laminate 70 had a specular reflectance of 1% for external light, the reflected light from the mirror 71 was reduced, and the texture of the wood grain pattern provided by the surface layer 15 was sufficiently obtained. When the laminate 70 had a specular reflectance of 1.5%, the light reflected by the mirror 71 was visible, and the texture of the wood grain pattern due to the surface layer 15 was obtained, but it was lower than when the specular reflectance was 1%. When the regular reflectance of the laminate 70 was 2%, the light reflected by the mirror 71 was very visible, and the texture of the wood grain pattern provided by the surface layer 15 could not be obtained.

[0096] From the above, it is desirable that the reflectance of external light inside the display device 10, and in the display device 10 of this embodiment, the regular reflectance of external light inside the display panel 12 in particular, is 1% or less.

[0097] (Transformed form) The present invention is not limited to the above-described embodiment, and various modifications and variations are possible, and these are also within the scope of the present invention.

[0098] (1) Although the display device 10 is a liquid crystal display device in the above example, it is not limited to this and may be a plasma display, an organic EL display, or the like. In the case of a plasma display, distance S is the distance from the bottom of a valley in the uneven surface of the surface layer 15 to the observer-facing surface of the phosphor inside the display. In the case of an organic EL display, distance S is the distance from the bottom of a valley in the uneven surface of the surface layer 15 to the observer-facing surface of the organic EL material layer inside the display. In addition, in the case of a plasma display or an organic EL display, it is preferable that the specular reflectance of external light inside the display device is 1% or less.

[0099] (2) The display device 10 may be disposed, for example, on an instrument panel of an automobile or in the interior of a vehicle or ship.

[0100] The following additional notes are further disclosed regarding the above-described embodiment and modifications. (Appendix 1) A display device that displays an image on a display surface, the display device having a surface layer closest to the viewer that is optically transparent and has an uneven shape on the viewer side, the uneven shape having an arithmetic mean roughness Ra of 10 μm or more and 3000 μm or less, the haze value of the surface layer being 40% or more and 85% or less, the distance from the lowest point of the uneven shape to an image forming layer that forms the image to be displayed in the thickness direction of the display device being 0.3 mm or less, and the decrease in brightness in a direction at an angle of 60° to the normal direction of the surface on which the surface layer is laminated being 45% or less, based on the brightness in the normal direction of the surface.

[0101] (Appendix 2) The display device according to Appendix 1 includes a sensor unit that detects the brightness and color of external light incident on the display surface, and an image adjustment unit that adjusts the brightness and color of the image to be displayed based on the information on the brightness and color of the external light detected by the sensor unit.

[0102] (Appendix 3) 2. The display device according to claim 1, wherein the uneven shape has irregular depths of the recesses, irregular heights of the protrusions, and irregular distribution of the unevenness in the surface direction of the surface layer.

[0103] (Note 4) 2. The display device according to claim 1, wherein the haze value at the outermost surface of the uneven shape is non-uniformly distributed in the plane direction of the surface layer.

[0104] (Note 5) 2. The display device according to claim 1, wherein the specular reflectance of external light incident on the display device is 1% or less inside the display device.

[0105] (Note 6) An electronic device equipped with a display device according to any one of Supplementary Note 1 to Supplementary Note 5.

[0106] The present invention is not limited to the above-described embodiments and variations, and may be combined as desired. [Explanation of symbols]

[0107] 1 Electronic equipment 10 Display device 11 Backlight 12 Display panel 15 Surface layer 151 Base material layer 152 Uneven shape layer 20 Display control unit 21 Image adjustment section 22 Electrode Control Unit 23 Light source control unit 24 Memory section 25 Sensor section

Claims

1. A display device, a surface layer on the side closest to the viewer, which is optically transparent and has an uneven shape on the viewer side; The arithmetic mean roughness Ra of the uneven shape is 10 μm or more and 3000 μm or less, the haze value of the surface layer is 40% or more and 85% or less, a distance in a thickness direction of the display device from a point where the concave-convex shape has its lowest point to a viewer-side surface of an image forming layer that is located on the rear side of the surface layer and has an element that forms a displayed image, is 0.3 mm or less; On the surface on which the surface layer is laminated, a decrease rate of brightness in a direction forming an angle of 60° with respect to the normal direction of the surface is 45% or less, based on brightness in the normal direction of the surface; a sensor unit that detects the brightness and color of external light incident on a display surface that is the viewer side surface of the surface layer; an image adjustment unit that adjusts the brightness and color of an image displayed by the display device based on information about the brightness and color of the external light detected by the sensor unit; A display device comprising:

2. The uneven shape has irregular depths of recesses, irregular heights of protrusions, and irregular distribution of the unevenness in the surface direction of the surface layer. The display device according to claim 1 .

3. the haze value at the outermost surface of the uneven shape is not uniformly distributed in the plane direction of the surface layer; The display device according to claim 1 .

4. An electronic device comprising the display device according to any one of claims 1 to 3.

Images