Display device

Abstract

To provide a display device that can improve the appearance of an object on which the display device is installed.SOLUTION: A display device 13 comprises: a translucent panel 14; a light source for display that is arranged inside the translucent panel 14 and enables display by irradiating light to the translucent panel 14; and a housing 16 that accommodates the light source for display and has an opening on the translucent panel 14 side. The translucent panel 14 has: a transparent resin base material 21; a first coloring layer 23 containing dye or pigment; and a second coloring layer 24 containing a filler 27 that is composed of a cold mirror thin film that reflects visible light and transmits infrared rays. The first coloring layer 23 has a permeability of 20% or more for light of a specific wavelength. The second coloring layer 24 has a reflectance of 80% or less for light of a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23, and a permeability of 60% or more for light of a wavelength that is absorbed by the dye or pigment of the first coloring layer 23.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a display device mounted on, for example, a vehicle. [Background technology]

[0002] For example, a light-emitting grille is known as a type of display device mounted on a vehicle (see, for example, Patent Document 1). Such a light-emitting grille has a light-transmitting outer cover and a light-emitting element disposed inside the outer cover. The light-emitting grille emits light at night when light from the light-emitting element passes through the outer cover. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2022-35593 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, the illuminating grille is not normally illuminated during the day. When the illuminating grille is not illuminated and is irradiated with external light such as sunlight, part of the light passes through the outer cover and the rest is reflected by the outer cover. On the other hand, when external light such as sunlight is irradiated on the hood adjacent to the illuminating grille in the vehicle, the hood reflects most of the light. This results in a significant difference between the appearance of the illuminating grille and the appearance of the hood, which creates a problem of degraded appearance of the vehicle equipped with the illuminating grille.

[0005] These problems are not limited to display devices provided in vehicles, but are also common to display devices provided on moving objects other than vehicles, on the outer walls of buildings, and the like. [Means for solving the problem]

[0006] Various aspects of the display device for solving the above problems will be described below. [Aspect 1] A display device comprising a light-transmitting section provided on a panel having electromagnetic wave transparency, a display light source arranged inside the light-transmitting section and enabling display by irradiating light onto the light-transmitting section, and a housing that contains the display light source and has an opening on the light-transmitting section side, wherein the light-transmitting section has a transparent resin base material, a first color-producing layer containing a dye or pigment, and a second color-producing layer containing a filler and composed of a cold mirror thin film that reflects visible light and transmits infrared light, wherein the first color-producing layer has a transmittance of 20% or more for light of a specific wavelength, and the second color-producing layer has a reflectance of 80% or less for light of a wavelength that is not absorbed by the dye or pigment of the first color-producing layer and a transmittance of 60% or more for light of a wavelength that is absorbed by the dye or pigment of the first color-producing layer.

[0007] According to the above configuration, at night, by irradiating light from the display light source onto the light-transmitting portion, the light passes through the light-transmitting portion and travels to the outside, so that display can be performed by the light emitted from the light-transmitting portion. On the other hand, during the day, even if light is not emitted from the display light source, the first coloring layer and the second coloring layer can appropriately reflect and transmit light from the outside, and the light that has passed through the first coloring layer and the second coloring layer from the outside can be reflected by the housing and guided to the outside through the light-transmitting portion. This makes it possible to increase the amount of light going out from the light-transmitting portion to the outside. Therefore, the amount of light going out from the light-transmitting portion to the outside can be made to be close to the amount of light emitted to the outside from a non-light-transmitting panel, which is an example of a non-light-transmitting portion that is arranged adjacent to the light-transmitting portion and reflects almost 100% of the light from the outside. As a result, the exterior color of the light-transmitting portion can be made close to the exterior color of the non-light-transmitting panel, so that the boundary between the light-transmitting portion and the non-light-transmitting panel becomes less noticeable. This makes it possible to improve the appearance of the object on which the display device is provided.

[0008] [Aspect 2] The display device according to [Aspect 1], characterized in that a reflective portion is provided on the surface of the housing facing the translucent portion to facilitate reflection of light. According to the above configuration, the reflective portion can efficiently reflect the light that has entered the housing toward the light-transmitting portion, thereby further increasing the amount of light that passes through the light-transmitting portion from inside the housing to the outside.

[0009] [Aspect 3] The display device according to [Aspect 1] or [Aspect 2], wherein the light-transmitting portion has an infrared transmittance of 60% or more and an attenuation rate of millimeter waves of 3.0 dB or less. According to the above configuration, when an electromagnetic wave sensor such as an infrared sensor or a millimeter wave sensor is arranged inside the light-transmitting portion, the light-transmitting portion can function as an electromagnetic wave-transmitting cover for covering the infrared sensor, millimeter wave sensor, etc. Effect of the Invention

[0010] The present invention has an effect of improving the appearance of an object on which a display device is provided. [Brief description of the drawings]

[0011] [Figure 1] 1 is a schematic cross-sectional view showing an exterior structure of a vehicle according to an embodiment. [Diagram 2] FIG. 2 is an enlarged view of a main part of FIG. [Diagram 3] FIG. 4 is an enlarged view of a main portion of the second color layer. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Hereinafter, an embodiment in which the display device is embodied as a display device provided in a vehicle will be described with reference to the drawings. <Vehicle 11 Configuration> As shown in FIG. 1, a vehicle 11 includes a non-translucent panel 12 and a display device 13. The vehicle 11 is an example of an object on which the display device 13 is provided. The display device 13 includes a translucent panel 14 as an example of a translucent portion provided on a panel having electromagnetic wave transparency, a display light source 15, and a housing 16. The non-translucent panel 12 as an example of a non-translucent portion constitutes, as an example, a hood 17 located at the front of the vehicle 11. The display device 13 constitutes, as an example, a light-emitting grille 18. The light-translucent panel 14 constitutes, as an example, the exterior of the light-emitting grille 18 located at the front of the vehicle 11.

[0013] The light-transmitting panel 14 is disposed around the non-light-transmitting panel 12. That is, the light-transmitting panel 14 is disposed adjacent to the underside of the non-light-transmitting panel 12. The exterior colors of the non-light-transmitting panel 12 and the light-transmitting panel 14 are similar to each other. An infrared sensor 19 and a millimeter wave sensor 20 are disposed vertically adjacent to each other at a position behind the display device 13 in the vehicle 11.

[0014] The infrared sensor 19 transmits infrared rays (near-infrared rays) having a wavelength of, for example, 900 nm among electromagnetic waves toward the front of the vehicle 11, and receives the infrared rays reflected by objects outside the vehicle, including preceding vehicles and pedestrians, etc. Based on the transmitted and received infrared rays, the infrared sensor 19 recognizes the above objects outside the vehicle, and detects the distance, relative speed, etc. between the vehicle 11 and the above objects. The infrared sensor 19 has a feature that it can detect objects smaller than those that the millimeter wave sensor 20 can detect.

[0015] The millimeter wave sensor 20 transmits millimeter waves, which are electromagnetic waves, toward the front of the vehicle 11 and receives millimeter waves reflected by objects outside the vehicle, including preceding vehicles and pedestrians. Based on the transmitted and received millimeter waves, the millimeter wave sensor 20 recognizes the objects outside the vehicle and detects the distance and relative speed between the vehicle 11 and the objects. Millimeter waves are radio waves with a wavelength of 1 mm to 10 mm and a frequency of 30 GHz to 300 GHz. The millimeter wave sensor 20 is characterized by being resistant to bad weather such as rain, fog, and snow, and having a longer detectable distance than the infrared sensor 19.

[0016] <Non-translucent Panel 12> 1, the non-light-transmitting panel 12 does not transmit external light such as sunlight, etc. In other words, the non-light-transmitting panel 12 reflects almost 100% of external light.

[0017] <Translucent Panel 14> 1 and 2, the light-transmitting panel 14 reflects and transmits external light such as sunlight. That is, the light-transmitting panel 14 reflects a portion of the external light and transmits the remainder. When the light-transmitting panel 14 reflects, for example, 80% of the external light, it transmits the remaining 20%. The light-transmitting panel 14 is electromagnetic wave transmissive. That is, the light-transmitting panel 14 is infrared ray transmissive and millimeter wave transmissive.

[0018] The light-transmitting panel 14 has a plate-shaped transparent resin base material 21 and a decorative layer 22 laminated on the rear surface of the transparent resin base material 21. The decorative layer 22 has a first coloring layer 23 laminated on the rear surface of the transparent resin base material 21 and a second coloring layer 24 laminated on the rear surface of the first coloring layer 23. The transparent resin base material 21 is made of, for example, polycarbonate (PC) resin. The first coloring layer 23 is a layer in which a dye or pigment is contained in a first base resin 25.

[0019] The first coloring layer 23 preferably has a transmittance of 20% or more for light of a specific wavelength. The light of the specific wavelength is, for example, light of the same wavelength as the exterior color of the non-translucent panel 12. If the transmittance of the light of the specific wavelength in the first coloring layer 23 is less than 20%, there is a risk that the components of the exterior color of the non-translucent panel 12 will be insufficient when the display light source 15 emits light on the translucent panel 14. Furthermore, the first coloring layer 23 preferably has a transmittance of 20% for light of a wavelength absorbed by the dye or pigment. Furthermore, the first coloring layer 23 preferably has a transmittance of 100% for light of a wavelength not absorbed by the dye or pigment.

[0020] As shown in Figs. 2 and 3, the second coloring layer 24 is a layer in which a filler 27 composed of a cold mirror thin film is contained in a second base resin 26. The cold mirror thin film has the characteristic of reflecting visible light and transmitting infrared light. The second coloring layer 24 preferably has a reflectance of 80% or less for light having a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23. If the reflectance of the second coloring layer 24 for light having a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23 is 100%, the light irradiated from the display light source 15 and having a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23 will not be transmitted at all.

[0021] The second coloring layer 24 preferably has a transmittance of 60% or more for light of a wavelength absorbed by the dye or pigment of the first coloring layer 23. If the second coloring layer 24 has a transmittance of less than 60% for light of a wavelength absorbed by the dye or pigment of the first coloring layer 23, there is a risk that the amount of light of that wavelength that is reflected by the housing 16, passes through the translucent panel 14, and exits to the outside will be insufficient.

[0022] 1 and 2, the light-transmitting panel 14 preferably has a transmittance of 60% or more for infrared rays having a wavelength of, for example, 900 nm. If the light-transmitting panel 14 has a transmittance of less than 60% for infrared rays, the detection accuracy of the infrared sensor 19 may be insufficient. The light-transmitting panel 14 preferably has an attenuation rate of 3.0 dB or less for the round trip of millimeter waves. If the attenuation rate of the millimeter waves in the light-transmitting panel 14 exceeds 3.0 dB for the round trip of millimeter waves, the detection accuracy of the millimeter wave sensor 20 may be insufficient.

[0023] <Housing 16> 1, the housing 16 is in the shape of a rectangular box with a bottom and an opening 28 at the front end. The opening 28 of the housing 16 is closed by the transparent resin base material 21 of the light-transmitting panel 14. The housing 16 has the opening 28 on the light-transmitting panel 14 side. The decorative layer 22 of the light-transmitting panel 14 is located inside the housing 16.

[0024] The housing 16 is made of, for example, polycarbonate (PC) resin, acrylonitrile-butadiene-styrene copolymer (ABS) resin, acrylonitrile-ethylene-propylene-diene-styrene (AES) resin, acrylonitrile-styrene-acrylate copolymer (ASA) resin, or the like.

[0025] The display light sources 15 are provided at the upper and lower ends of the surface 29 of the housing 16 facing the light-transmitting panel 14. That is, the housing 16 accommodates two display light sources 15 therein. Therefore, each display light source 15 is disposed at a position behind (inside) the light-transmitting panel 14. The surface 29 of the housing 16 facing the light-transmitting panel 14 is provided with a reflecting portion 30 for facilitating reflection of light. That is, the facing surface 29 is covered with the reflecting portion 30. The reflecting portion 30 is formed of, for example, a white reflecting material or a reflecting mirror.

[0026] The display light source 15 has an LED (Light Emitting Diode) that emits visible light and a control circuit that controls the LED. The display light source 15 emits visible light onto the translucent panel 14, making it possible to emit light to display characters, pictures, and the like using the visible light that passes through the translucent panel 14.

[0027] <Operation of the embodiment> The vehicle 11 usually illuminates the display light source 15 when traveling at night. Then, light is irradiated from the display light source 15 to the translucent panel 14, and characters, pictures, etc. are illuminated and displayed by the light that passes through the translucent panel 14. At this time, since the transmittance of light of a specific wavelength in the first coloring layer 23 is 20% or more, the above-mentioned illuminated display also includes light of the specific wavelength.

[0028] Furthermore, at this time, when the reflectance of light of a wavelength not absorbed by the dye or pigment of the first coloring layer 23 is, for example, 80%, the second coloring layer 24 allows a certain degree of transmission of light of a wavelength not absorbed by the dye or pigment of the first coloring layer 23 among the light irradiated from the display light source 15. Therefore, the light of a wavelength not absorbed by the dye or pigment of the first coloring layer 23 is also included in the luminous display. Therefore, the light transmitting through the translucent panel 14 allows letters, pictures, etc. to be luminously displayed satisfactorily.

[0029] On the other hand, since the vehicle 11 does not normally illuminate letters, pictures, or the like on the translucent panel 14 when traveling during the day, the display light source 15 is not illuminated for illumination. In this case, the translucent panel 14 reflects a portion of sunlight, which is an example of external light, but transmits the remainder. At this time, the non-translucent panel 12 adjacent to the translucent panel 14 reflects almost all of the sunlight that is irradiated. For this reason, the reflectance of sunlight on the translucent panel 14 is smaller than the reflectance of sunlight on the non-translucent panel 12.

[0030] Therefore, the amount of sunlight reflected by the light-transmitting panel 14 is less than the amount of sunlight reflected by the non-light-transmitting panel 12. That is, a difference occurs between the amount of sunlight reflected by the light-transmitting panel 14 and the amount of sunlight reflected by the non-light-transmitting panel 12. If this difference becomes large, the color development will be significantly different between the light-transmitting panel 14 and the non-light-transmitting panel 12 even if the exterior colors of the light-transmitting panel 14 and the non-light-transmitting panel 12 are similar colors. As a result, the boundary between the light-transmitting panel 14 and the non-light-transmitting panel 12 becomes more noticeable, degrading the appearance of the vehicle 11.

[0031] In this regard, as shown in Fig. 2, in this embodiment, when the vehicle 11 is traveling in the daytime, the following occurs even if the display light source 15 is not illuminated. That is, when the light-transmitting panel 14 is irradiated with, for example, sunlight as external light, the sunlight passes through the transparent resin substrate 21 and the first coloring layer 23 to reach the second coloring layer 24. At this time, the sunlight is entirely transmitted through the transparent resin substrate 21. In addition, of the sunlight that has passed through the transparent resin substrate 21, 20% of the light having a wavelength that is absorbed by the dye or pigment of the first coloring layer 23 passes through the first coloring layer 23, and 100% of the light having a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23 passes through the first coloring layer 23.

[0032] Of the sunlight that reaches the second coloring layer 24, when light with a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23 is reflected by the second coloring layer 24, for example, 80% of the light is transmitted through the second coloring layer 24. Of the sunlight that reaches the second coloring layer 24, when light with a wavelength that is absorbed by the dye or pigment of the first coloring layer 23 is reflected by the second coloring layer 24, 60% or more of the light is transmitted through the second coloring layer 24. After being reflected by the reflecting portion 30, a portion of the sunlight that transmits through the translucent panel 14 goes out to the outside, as described above. As a result, the amount of light emitted to the outside from the translucent panel 14 increases.

[0033] As a result, the translucent panel 14 develops a color such that its exterior color is closer to the exterior color of the non-translucent panel 12. This is because the smaller the difference between the amount of light emitted from the translucent panel 14 to the outside and the amount of light emitted from the non-translucent panel 12 to the outside, the closer the exterior color of the non-translucent panel 12 and the exterior color of the translucent panel 14 will appear. As a result, the appearance of the translucent panel 14 becomes closer to the appearance of the non-translucent panel 12, making the boundary between the translucent panel 14 and the non-translucent panel 12 less noticeable. This improves the appearance of the vehicle 11.

[0034] 2, if the amount of incident sunlight 31 incident on each of the light-transmitting panel 14 and the non-light-transmitting panel 12 is 100, then in the light-transmitting panel 14, 80 of the 100 incident sunlight 31 are reflected as reflected light 32 and the remaining 20 are transmitted as transmitted light 33, whereas in the non-light-transmitting panel 12, 100 incident sunlight 31 are reflected as reflected light 32. In this state, the amount of light emitted to the outside from the light-transmitting panel 14 is 80, and the amount of light emitted to the outside from the non-light-transmitting panel 12 is 100.

[0035] However, after the transmitted light 33 of the light 20 that has passed through the light-transmitting panel 14 is reflected by the reflecting portion 30 of the housing 16, a part of the light 20 (hereinafter referred to as "A") passes through the light-transmitting panel 14 again from the inside of the light-transmitting panel 14 as an inward reflected light 34 and is emitted to the outside. Then, the amount of light emitted from the light-transmitting panel 14 to the outside is 80+A, so the difference between the amount of light emitted from the light-transmitting panel 14 to the outside and the amount of light emitted from the non-light-transmitting panel 12 to the outside is reduced by A. Therefore, the exterior color of the light-transmitting panel 14 approaches the exterior color of the non-light-transmitting panel 12. Therefore, the boundary between the light-transmitting panel 14 and the non-light-transmitting panel 12 becomes less noticeable, improving the appearance of the vehicle 11.

[0036] Moreover, the light-transmitting panel 14 has a transmittance of 60% or more for infrared rays with a wavelength of 900 nm, thereby ensuring the detection accuracy of the infrared sensor 19. Furthermore, the light-transmitting panel 14 has an attenuation rate of 3.0 dB or less for the round trip of millimeter waves, thereby ensuring the detection accuracy of the millimeter wave sensor 20. Therefore, the light-transmitting panel 14 also functions as an electromagnetic wave transmitting cover.

[0037] <Effects of the embodiment> According to the embodiment described above in detail, the following effects are achieved. (1) The display device 13 includes a light-transmitting panel 14 having electromagnetic wave transparency, a display light source 15 arranged inside the light-transmitting panel 14 and capable of displaying by irradiating the light-transmitting panel 14 with light, and a housing 16 that houses the display light source 15 and has an opening 28 on the light-transmitting panel 14 side. The light-transmitting panel 14 includes a transparent resin substrate 21, a first coloring layer 23 containing a dye or pigment, and a second coloring layer 24 containing a filler 27 formed of a cold mirror thin film that reflects visible light and transmits infrared light. The first coloring layer 23 has a transmittance of 20% or more for light of a specific wavelength. The second coloring layer 24 has a reflectance of 80% or less for light of a wavelength that is not absorbed by the dye or pigment of the first coloring layer 23, and a transmittance of 60% or more for light of a wavelength that is absorbed by the dye or pigment of the first coloring layer 23.

[0038] According to the above configuration, at night, by irradiating light from the display light source 15 onto the translucent panel 14, the light passes through the translucent panel 14 and travels to the outside, so that display can be performed by the light emission of the translucent panel 14. On the other hand, during the day, even if light is not emitted from the display light source 15, the first coloring layer 23 and the second coloring layer 24 can appropriately reflect and transmit light from the outside, and the light that has passed through the first coloring layer 23 and the second coloring layer 24 from the outside can be reflected by the housing 16 and guided to the outside through the translucent panel 14. This makes it possible to increase the amount of light that goes out from the translucent panel 14 to the outside. Therefore, the amount of light that goes out from the translucent panel 14 to the outside can be made close to the amount of light emitted to the outside from the non-translucent panel 12 that is disposed adjacent to the translucent panel 14 and reflects almost 100% of the light from the outside. As a result, the exterior color of the light-transmitting panel 14 can be made closer to the exterior color of the non-light-transmitting panel 12, making the boundary between the light-transmitting panel 14 and the non-light-transmitting panel 12 less noticeable, thereby improving the appearance of the vehicle 11 on which the display device 13 is installed.

[0039] (2) In the display device 13, the opposing surface 29 of the housing 16 that faces the light-transmitting panel 14 is provided with a reflecting portion 30 for facilitating reflection of light. According to the above-described configuration, the reflecting portion 30 can efficiently reflect the light that has entered the housing 16 toward the translucent panel 14. This makes it possible to further increase the amount of light that passes from inside the housing 16 through the translucent panel 14 and exits to the outside.

[0040] (3) In the display device 13, the light-transmitting panel 14 has an infrared transmittance of 60% or more and an attenuation rate of millimeter waves of 3.0 dB or less. According to the above configuration, when an electromagnetic wave sensor such as an infrared sensor 19 or a millimeter wave sensor 20 is arranged inside the translucent panel 14, the translucent panel 14 can function as an electromagnetic wave transparent cover for covering the infrared sensor 19, the millimeter wave sensor 20, etc.

[0041] <Example of change> The above embodiment can be modified as follows: The above embodiment and the following modifications can be combined with each other as long as they are not technically inconsistent.

[0042] The reflecting portion 30 may be omitted. In the light-transmitting panel 14 , a decorative layer 22 may be laminated on the front surface of the transparent resin base material 21 . The light-transmitting panel 14 does not necessarily have to have an infrared transmittance of 60% or more.

[0043] The light-transmitting panel 14 does not necessarily have to have an attenuation rate of millimeter waves of 3.0 dB or less. The light from outside is not limited to sunlight, but may be light from lighting equipment installed outdoors or indoors.

[0044] The decorative layer 22 may have at least one of a smoke layer for controlling reflected light and a complementary color layer for controlling the emitted color. The display device 13 may have a panel that constitutes its design surface, with translucent and non-translucent portions disposed adjacent to each other.

[0045] The display device 13 may be provided on an object other than the vehicle 11. Examples of the object include a food delivery robot, a drone, and the outer or inner wall of a building. [Explanation of symbols]

[0046] 11…Vehicle 12...Non-translucent panel as an example of a non-translucent portion 13...Display device 14...Translucent panel as an example of a translucent portion provided in a panel having electromagnetic wave transmissibility 15...Display light source 16. Housing 17…Food 18…Illuminated grille 19...Infrared sensor 20...Millimeter wave sensor 21...Transparent resin base material 22…Decorative layer 23…First color layer 24…Second color layer 25…First base resin 26…Second base resin 27…Filler 28…Opening 29…Opposite surface 30…Reflector 31...Incoming sunlight 32...Reflected light 33…Transmitted light 34…Inner reflected light

Claims

1. The display device includes a light-transmitting section provided on a panel having electromagnetic wave transparency, a display light source disposed inside the light-transmitting section and capable of displaying by irradiating the light-transmitting section with light, and a housing that contains the display light source and has an opening on the light-transmitting section side, the light transmitting portion has a transparent resin substrate, a first coloring layer containing a dye or a pigment, and a second coloring layer containing a filler and formed of a cold mirror thin film that reflects visible light and transmits infrared light; the first color-forming layer has a transmittance of 20% or more for light of a specific wavelength; A display device characterized in that the second coloring layer has a reflectance of 80% or less for light of a wavelength that is not absorbed by the dye or pigment of the first coloring layer, and a transmittance of 60% or more for light of a wavelength that is absorbed by the dye or pigment of the first coloring layer.

2. 2. The display device according to claim 1, wherein a reflecting portion for facilitating reflection of light is provided on a surface of the housing facing the light transmitting portion.

3. 3. The display device according to claim 1, wherein the light transmitting portion has an infrared transmittance of 60% or more and an attenuation rate of millimeter waves of 3.0 dB or less.

Images