Patent Application
20230299058
The present invention relates to a transparent display device, a laminated glass, and a manufacturing method of the transparent display device.
Display devices which use a light-emitting diode (LED) element in a pixel are known. Published Japanese Translation of PCT International Publication for Patent Application No. 2017-521859 discloses, among such display devices, a transparent display device in which a size of an LED element is minute and of which a rear-face side is visually recognizable via the display device.
With transparent display devices, there is a demand to make an image to be displayed to a viewing side not visually recognizable from the rear-face side (an opposite side of the viewing side). In other words, there is a demand to suppress leakage to the rear-face side of light emitted from an LED element.
A transparent display device disclosed in Japanese Unexamined Patent Application Publication No. 2009-186905 is provided with a light-shielding member which blocks light emitting from a through-hole packaged LED (light emitter) from being transmitted to a rear-face side on which the light emitter is not arranged.
However, even when the light-shielding member for a through-hole packaged LED disclosed in Japanese Unexamined Patent Application Publication No. 2009-186905 is applied to a transparent display device using an LED element with an area of 10,000 μm2 or less, leakage to the rear-face side of light emitted from the LED element cannot be sufficiently suppressed.
The present invention has been made in consideration of such circumstances and an object thereof is to provide a transparent display device capable of suppressing leakage to a rear-face side of light emitted from an LED element.
The present invention provides a transparent display device configured as described in [1] below.
In an aspect of the present invention,
The present invention provides a laminated glass configured as described in [11] below.
The present invention provides a manufacturing method of a transparent display device configured as described in [12] below.
According to the present invention, a transparent display device capable of suppressing leakage to a rear-face side of light emitted from an LED element can be provided.
The above and other objects, features and advantages of the present disclosure will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not to be considered as limiting the present disclosure.
Hereinafter, specific embodiments to which the present invention has been applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In addition, for the sake of brevity, the following descriptions and the drawings have been simplified as appropriate.
In the present specification, a “transparent display device” refers to a display device which causes visual information related to a person, a background, or the like positioned on a rear-face side of the display device to be visually recognizable under a desired use environment. Note that whether or not visually recognizable is determined in a state where at least the display device is not displayed or, in other words, the display device is not energized.
In the present specification, “transparent” refers to transmittance of visible light being 40% or higher, preferably 60% or higher, and more preferably 70% or higher. Alternatively, “transparent” may refer to transmittance being 5% or higher and a haze value being 20 or smaller. A transmittance of 5% or higher enables outdoors to be viewed with a brightness equal to or higher than indoors when the outdoors is viewed from indoors during the day and enables superior visibility to be secured.
In addition, a transmittance of 40% or higher enables the rear-face side of the transparent display device to be substantially visually recognized without incident even when brightness on a front-face side and brightness on the rear-face side of the transparent display device are more or less the same. Furthermore, a haze value of 10 or smaller enables contrast of the background to be sufficiently secured.
“Transparency” is realized regardless of whether color is imparted or not or, in other words, “transparent” may refer to being colorless and transparent or being colored and transparent.
Note that transmittance refers to a value (%) measured by a method conforming to ISO 9050. A haze value refers to a value measured by a method conforming to ISO 14782.
First, a configuration of a transparent display device according to a first embodiment will be explained with reference to
As shown in
It should be understood that right-handed system xyz orthogonal coordinates shown in
In addition, in
First, a planar arrangement of the light-emitting unit 20, the IC chip 30, the wiring 40, and the light-shielding film 60 will be described with reference to
As shown in
Note that an arrangement format of the pixel PIX or, in other words, the light-emitting unit 20 is not limited to a matrix pattern as long as the pixel PIX or the light-emitting unit 20 is arranged at a predetermined pixel pitch in a predetermined direction.
As shown in
In the example shown in
Note that each light-emitting unit 20 may include two or more LED elements of a same color. Accordingly, a dynamics range of an image can be expanded.
The LED elements 21 to 23 are so-called micro LED elements which are semiconductor chips with an area of 10,000 μm2 or less. Specifically, a width (a length in the x-axis direction) and a length (a length in the y-axis direction) of the LED element 21 on the transparent substrate 10 are, respectively, for example, 100 μm or less, preferably 50 μm or less, and more preferably 20 μm or less. A similar description applies to the LED elements 22 and 23. Due to various manufacturing conditions and the like, a lower limit of the width and the length of the LED elements is, for example, 3 μm or more.
Note that while dimensions or, in other words, the widths and the lengths of the LED elements 21 to 23 in
In addition, an area of the LED elements 21 to 23 on the transparent substrate 10 is preferably 3,000 μm2 or less and more preferably 500 μm2 or less. Due to various manufacturing conditions and the like, a lower limit of the area occupied by one LED element is, for example, 10 μm2 or more. In the present specification, an area of an LED element or an area of a constituent member such as a wiring indicates an area occupied by the LED element or the constituent member such as a wiring in an xy plan view in
While a shape of the LED elements 21 to 23 shown in
In this case, for example, transmittance of the LED elements 21 to 23 is low at around 10% or lower. However, in the transparent display device according to the present embodiment, as described earlier, the LED elements 21 to 23 with a minute size of which an area is 10,000 μm2 or less are used. Therefore, for example, even when the transparent display device is observed from a short distance of around several 10 cm to 2 m, the LED elements 21 to 23 are hardly visually recognizable. In addition, a region with low transmittance in the display region 101 is narrow and superior visibility of the rear-face side can be secured. Furthermore, a degree of freedom of an arrangement of the wiring 40 and the like is also high.
Note that “a region with low transmittance in the display region 101” is, for example, a region of which transmittance is 20% or lower. A similar description applies hereinafter.
In addition, since the LED elements 21 to 23 with a minute size are used, the LED elements are less susceptible to damage even when the transparent display device is bent. Therefore, the transparent display device according to the present embodiment can be used by mounting the transparent display device to a curved transparent plate such as a window glass for a vehicle or sealing the transparent display device between two curved transparent plates. In this case, using a material with flexibility as the transparent substrate 10 enables the transparent display device according to the present embodiment to be curved.
Although not particularly limited, the LED elements 21 to 23 are made of, for example, inorganic materials. For example, the red-colored LED element 21 is made of AlGaAs, GaAsP, GaP, or the like. For example, the green-colored LED element 22 is made of InGaN, GaN, AlGaN, GaP, AlGaInP, ZnSe, or the like. For example, the blue-colored LED element 23 is made of InGaN, GaN, AlGaN, ZnSe, or the like. In addition, the LED elements 21 to 23 may be configured to not only emit unpolarized light but to also emit polarized light. A function of emitting polarized light is realized by providing a structure with a shorter pitch than a wavelength of light to be emitted inside or on a surface of the LED elements 21 to 23, providing a material with chirality inside or on a surface of the LED elements 21 to 23, or the like. Furthermore, when the LED elements 21 to 23 emit polarized light, arranging a member such as a polarizing film which absorbs or reflects specific polarized light on the rear-face side is preferable since light leaking to the rear-face side can be suppressed. The polarizing film may act on any of linear polarized light and circular polarized light.
Luminous efficiency or, in other words, energy conversion efficiency of the LED elements 21 to 23 is, for example, 1% or higher, preferably 5% or higher, and more preferably 15% or higher. When the luminous efficiency of the LED elements 21 to 23 is 1% or higher, sufficient brightness is obtained even with the LED elements 21 to 23 having minute sizes as described above and the LED elements 21 to 23 can be used as a display device even during the day. In addition, when the luminous efficiency of the LED elements is 15% or higher, heat generation is suppressed and the LED elements can be readily sealed inside a laminated glass using a resin adhesion layer.
The pixel pitches Px and Py are, respectively, for example, 100 to 3,000 μm, preferably 180 to 1,000 μm, and more preferably 250 to 400 μm. Setting the pixel pitches Px and Py to the range described above enables high transparency to be realized while securing sufficient display capability. In addition, a diffraction phenomenon which may occur due to light from the rear-face side of the transparent display device can be suppressed.
Furthermore, a pixel density in the display region 101 of the transparent display device according to the present embodiment is, for example, 10 ppi or higher, preferably 30 ppi or higher, and more preferably 60 ppi or higher.
In addition, an area of one pixel PIX is expressed as Px×Py. An area of one pixel is, for example, 1×104 μm2 to 9×106 μm2, preferably 3×104 μm2 to 1×106 μm2, and more preferably 6×104 μm2 to 2×105 μm2. Setting the area of one pixel to 1×104 μm2 to 9×106 μm2 enables transparency of the display device to be improved while securing suitable display capability. The area of one pixel may be appropriately selected based on a size, a usage, a visual recognition distance, or the like of the display region 101.
A percentage of the area occupied by the LED elements 21 to 23 with respect to the area of one pixel is, for example, 30% or less, preferably 10% or less, more preferably 5% or less, and even more preferably 1% or less. Setting the percentage of the area occupied by the LED elements 21 to 23 with respect to the area of one pixel to 30% or less improves transparency and visibility of the rear-face side.
In
Furthermore, as shown in
While an arrangement order, an arrangement direction, and the like of the plurality of LED elements in each light-emitting unit 20 are the same in the example shown in
In the example shown in
Alternatively, the IC chip 30 may be arranged for every plurality of pixels and each IC chip 30 may drive the plurality of pixels to which the IC chip 30 is connected. For example, by arranging one IC chip 30 for every four pixels, the number of IC chips 30 can be reduced to ¼ as compared to the example shown in
An area of the IC chip 30 is, for example, 100,000 μm2 or less, preferably 10,000 μm2 or less, and more preferably 5,000 μm2 or less. While a transmittance of the IC chip 30 is low at around 20% or less, using the IC chip 30 with the size described above narrows a region with low transmittance in the display region 101 and improves visibility of the rear-face side.
As shown in
In the example shown in
In addition, in each pixel PIX, the power supply line 41 and the column data line 44 are provided more toward a side of a negative x-axis direction than the light-emitting unit 20 and the IC chip 30 and the ground line 42 is provided more toward a side of the positive x-axis direction than the light-emitting unit 20 and the IC chip 30. In this case, the power supply line 41 is provided more toward the side of the negative x-axis direction than the column data line 44. In addition, in each pixel PIX, the row data line 43 is provided more toward a side of the negative y-axis direction than the light-emitting unit 20 and the IC chip 30.
Furthermore, while details will be provided later, as shown in
As shown in
In addition, in each pixel PIX, the IC chip 30 is provided more toward a side of the negative y-axis direction than the LED elements 21 to 23. Therefore, between the LED element 21 and the column data line 44, the second power supply branch line 41b having been branched in the negative y-axis direction from the first power supply branch line 41a is linearly extended and connected to a side in the negative x-axis direction of the end part on a side of the positive y-axis direction of the IC chip 30.
As shown in
In this case, the ground line 42 is connected to the LED elements 21 to 23 with the ground branch line 42a, the IC chip 30, and the drive line 45 interposed therebetween.
As shown in
In this case, the row data line 43 is connected to the LED elements 21 to 23 with the row data branch line 43a, the IC chip 30, and the drive line 45 interposed therebetween.
As shown in
In this case, the column data line 44 is connected to the LED elements 21 to 23 with the column data branch line 44a, the IC chip 30, and the drive line 45 interposed therebetween.
The drive line 45 connects the LED elements 21 to 23 and the IC chip 30 to each other in each pixel PIX. Specifically, in each pixel PIX, three drive lines 45 are extended in the y-axis direction, and each drive line 45 connects end parts on a side of the negative y-axis direction of the LED elements 21 to 23 and an end part on a side of the positive y-axis direction of the IC chip 30 to each other.
Note that the arrangements of the power supply line 41, the ground line 42, the row data line 43, the column data line 44, branch lines thereof, and the drive line 45 shown in
Furthermore, a configuration in which the entire configuration shown in
Moreover, the row data line 43, the column data line 44, branch lines thereof, and the drive line 45 are not essential.
For example, the wiring 40 is made of a metal such as copper (Cu), aluminum (Al), silver (Ag), or gold (Au). Among these metals, a metal containing copper or aluminum as a main component is preferable due to low resistivity and from a cost perspective. In addition, the wiring 40 may be coated with a material such as titanium (Ti), molybdenum (Mo), copper oxide, or carbon for the purpose of reducing reflectance. Furthermore, irregularities may be formed on a surface of the coated material.
All of the widths of the wiring 40 in the display region 101 shown in
When the wiring 40 is mainly extended in the x-axis direction and the y-axis direction as shown in
Electrical resistivity of the wiring 40 is, for example, 1.0×10−6 Ωm or less and preferably 2.0×10−8 Ωm or less. In addition, thermal conductivity of the wiring 40 is, for example, 150 to 5,500 W/(m·K) and preferably 350 to 450 W/(m·K).
Intervals between adjacent wirings 40 in the display region 101 shown in
Note that when intervals between wirings 40 are not constant due to the wirings 40 being curved or the like, the intervals between the adjacent wirings 40 described above refer to a minimum value of the intervals.
A percentage of the area occupied by the wiring 40 with respect to the area of one pixel is, for example, 30% or less, preferably 10% or less, more preferably 5% or less, and even more preferably 3% or less. The transmittance of the wiring 40 is low at, for example, 20% or less or 10% or less. However, by setting the area occupied by the wiring in one pixel to 30% or less, a region with low transmittance in the display region 101 narrows and the visibility of the rear-face side improves.
Furthermore, a sum of areas occupied by the light-emitting unit 20, the IC chip 30, and the wiring 40 with respect to the area of one pixel is, for example, 30% or less, preferably 20% or less, and more preferably 10% or less.
The light-shielding film 60 is formed so as to cover an entire main surface on the rear-face side in each of the LED elements 21 to 23. Therefore, as shown in
For example, the light-shielding film 60 is a black resin film, a metal oxide film, a metal nitride film, or the like with insulation properties. More specifically, for example, the light-shielding film 60 is a black resist film, a carbon-based material such as carbon black, a film in which Cr, Mo, Ti, Al, or the like is entirely or partially oxidized or nitrided, and the like. The light-shielding film 60 may be a metallic film with conductivity such as a metal Cr film. In addition, a resin containing a filler of such a material may be used as the light-shielding film 60. Furthermore, preferably, an effective refractive index of the resin containing a filler is comparable to a refractive index of the surrounding transparent substrate 10 or the protective layer 50 or a difference in refractive indices is within 0.2. Moreover, in order to suppress reflection of light by the light-shielding film 60, a surface of the light-shielding film 60 is preferably not smooth.
As shown in
Although the larger the area of the light-shielding film 60, the greater the suppression of leakage of such reflected light to the rear-face side, visibility of the rear-face side declines. Therefore, for example, the area of the light-shielding film 60 is 0.6 times the area of one pixel or less, preferably 0.4 times or less, and more preferably 0.2 times or less.
Next, a sectional configuration of the transparent display device according to the present embodiment will be explained with reference to
The transparent substrate 10 is made of a transparent material with insulation properties. In the example shown in
As will be described in detail later, the main substrate 11 is made of, for example, a transparent resin.
The adhesive layer 12 is made of, for example, a transparent resin adhesive such as an epoxy-based adhesive, an acrylic adhesive, an olefin-based adhesive, a polyimide-based adhesive, or a novolac-based adhesive.
Alternatively, the main substrate 11 may be a thin glass plate with a thickness of, for example, 200 μm or less and, preferably, 100 μm or less. In addition, the adhesive layer 12 is not essential.
Examples of the transparent resin which constitutes the main substrate 11 include: a polyester-based resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN); an olefin-based resin such as a cycloolefin polymer (COP) or a cycloolefin copolymer (COC); a cellulose-based resin such as cellulose, acetyl cellulose, or triacetyl cellulose (TAC); an imide-based resin such as polyimide (PI); an amide-based resin such as polyamide (PA); an amide-imide-based resin such as polyamide-imide (PAI); a carbonate-based resin such as polycarbonate (PC); a sulfone-based resin such as polyether sulfone (PES); a paraxylene-based resin such as poly-paraxylene; a vinyl-based resin such as polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), or polyvinyl butyral (PVB); an acrylic resin such as polymethylmethacrylate (PMMA); an ethylene-vinyl acetate copolymer resin (EVA); a urethane-based resin such as thermoplastic polyurethane (TPU); and an epoxy-based resin.
Among the materials which may be used in the main substrate 11 described above, polyethylene naphthalate (PEN) or polyimide (PI) is preferable from the perspective of improving heat resistance. In addition, a cycloolefin polymer (COP), a cycloolefin copolymer (COC), polyvinyl butyral (PVB), or the like is preferable in terms of a low birefringence index and an ability to reduce distortion or blurring of an image viewed through the transparent substrate.
The materials described above may be used alone or two or more may be used in combination. Furthermore, the main substrate 11 may be constructed by laminating flat plates made of different materials.
A thickness of the entire transparent substrate 10 is, for example, 3 to 1,000 μm and, preferably, 5 to 200 μm.
In addition, the transparent substrate 10 may have flexibility. Accordingly, for example, the transparent display device can be used by mounting the transparent display device to a curved transparent plate or by sandwiching the transparent display device between two curved transparent plates. Furthermore, the transparent substrate 10 may be made of a material which contracts when heated to 100° C. or higher.
As shown in
In this case, as shown in
As shown in
As shown in
A thickness of the wiring 40 or, in other words, a sum of a thickness of the first metal layer M1 and a thickness of the second metal layer M2 is, for example, 0.1 to 10 μm and, preferably, 0.5 to 5 μm. The thickness of the first metal layer M1 is, for example, around 0.5 μm, and the thickness of the second metal layer M2 is, for example, around 3 μm.
Specifically, as shown in
In this case, as shown in
In a similar manner, in the intersections of the column data line 44 and the first power supply branch line 41a shown in
Furthermore, in the example shown in
As described above, the first power supply branch line 41a is solely constituted of the first metal layer M1 in intersections with the column data line 44 but solely constituted of the second metal layer M2 in other locations. Alternatively, a metal pad made of copper, silver, gold, or the like may be arranged on the wiring 40 formed on the transparent substrate 10 and at least one of the LED elements 21 to 23 and the IC chip 30 may be arranged on the metal pad.
The protective layer 50 is made of a transparent resin formed on approximately an entire surface of the transparent substrate 10 so as to cover and protect the light-emitting unit 20, the IC chip 30, and the wiring 40.
A thickness of the protective layer 50 is, for example, 3 to 1,000 μm and, preferably, 5 to 200 μm.
A modulus of elasticity of the protective layer 50 is, for example, 10 GPa or lower. A lower modulus of elasticity enables an impact upon separation to be absorbed and suppresses damage to the protective layer 50.
Internal transmittance of visible light of the protective layer 50 is, for example, 50% or higher, preferably 70% or higher, and more preferably 90% or higher.
In order to prevent light from being confined in the protective layer 50 and to extract the light to the viewing side (the side of the positive z-axis direction), the refractive index of the protective layer 50 is preferably lower than a refractive index of a transparent layer (not illustrated in
On the other hand, when an in-plane average thickness of the protective layer 50 is set smaller than a pitch of one pixel, the refractive index of the protective layer 50 is conversely preferably higher than the refractive index of the transparent layer which the protective layer 50 comes into contact with on the viewing side of the light-emitting unit 20. This is because, by confining light inside the protective layer 50 and guiding the light, light is effectively absorbed by the light-shielding film 60, the wiring 40, and the like which are in contact with the protective layer 50 on the rear-face side and leakage of the light to the rear-face side can be suppressed. In this case, more preferably, the thickness of the protective layer 50 is thinner than a longest side of the light-shielding film 60. Note that even when a transparent layer is further formed between the light-shielding film 60, the wiring 40, or the like and the protective layer 50, a similar effect can be produced if a refractive index of the transparent layer is higher than that of the protective layer 50.
Examples of the transparent resin which constitutes the protective layer 50 include: a vinyl-based resin such as polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA), or polyvinyl butyral (PVB); an olefin-based resin such as a cycloolefin polymer (COP) or a cycloolefin copolymer (COC); a urethane-based resin such as thermoplastic polyurethane (TPU); a polyester-based region such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN); an acrylic resin such as polymethylmethacrylate (PMMA); and a thermoplastic resin such as ethylene-vinyl acetate copolymer resin (EVA).
As described above, in the transparent display device according to the present embodiment, the entire main surface on the rear-face side is covered by the light-shielding film 60 in each of the LED elements 21 to 23. Therefore, light emitted from the LED elements 21 to 23 can be prevented from directly leaking to the rear-face side.
In addition, the light-shielding film 60 is formed so as to protrude from the main surface on the rear-face side of the LED elements 21 to 23. Therefore, light emitted from the LED elements 21 to 23 to the viewing side and reflected to the rear-face side can be prevented from leaking to the rear-face side.
Furthermore, by setting internal transmittance of visible light of a transparent member (the transparent substrate 10) positioned more toward the rear-face side than the light-shielding film 60 to 90% or lower, leakage of such reflected light to the rear-face side can be further suppressed.
Next, an example of a manufacturing method of the transparent display device according to the first embodiment will be explained with reference to
First, as shown in
Note that the lower-layer wiring is not formed in intersections of the power supply line 41, the ground line 42, and the column data line 44 with the row data line 43.
Next, as shown in
Next, as shown in
In this case, the LED elements 21 to 23 are obtained by growing a crystal on a wafer using a liquid phase growth method, an HVPE (hydride vapor phase epitaxy) method, a MOCVD (metal organic chemical vapor deposition) method, or the like and then performing patterning. The LED elements 21 to 23 having been patterned on the wafer are transferred onto the transparent substrate 10 using, for example, a micro-transfer printing technique. In addition, regarding the IC chip 30, for example, the IC chip 30 having been patterned on a Si wafer is transferred onto the transparent substrate 10 using a micro-transfer printing technique in a similar manner to the LED elements 21 to 23.
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Next, as shown in
Finally, as shown in
Next, a transparent display device according to a modified example of the first embodiment will be explained with reference to
In the example shown in
In addition, as shown in
On the other hand, in the transparent display device according to the modified example, the transparent substrate 10 is positioned more toward the viewing side than the LED elements 21 to 23. Therefore, internal transmittance of visible light of the transparent substrate 10 is, for example, 50% or higher, preferably 70% or higher, and more preferably 90% or higher.
As described above, even in the transparent display device according to the modified example, the entire main surface on the rear-face side is covered by the light-shielding film 60, the first power supply branch line 41a, and the drive line 45 which function as a light-shielding film in each of the LED elements 21 to 23. Therefore, light emitted from the LED elements 21 to 23 can be prevented from directly leaking to the rear-face side.
In addition, the light-shielding film 60 is formed so as to protrude from the main surface on the rear-face side of the LED elements 21 to 23. Therefore, light emitted from the LED elements 21 to 23 to the viewing side and reflected to the rear-face side can be prevented from leaking to the rear-face side.
Furthermore, by setting internal transmittance of visible light of a transparent member (the protective layer 50) positioned more toward the rear-face side than the light-shielding film 60 to 90% or lower, leakage of such reflected light to the rear-face side can be further suppressed.
The configuration is otherwise similar to that of the transparent display device according to the first embodiment.
Next, a transparent display device according to a second embodiment will be explained with reference to
As shown in
The configuration is otherwise similar to that of the transparent display device according to the first embodiment.
Note that a similar effect can be produced even when an antireflective film is formed on the lower surface (on the main surface on the viewing side) of the transparent substrate 10 in the transparent display device shown in
Next, a transparent display device according to a third embodiment will be explained with reference to
As shown in
As shown in
Note that the third power supply branch lines 41c and the drive line 45 are separated from each other and are not electrically short-circuited to each other.
As shown in
According to such a configuration, in the transparent display device according to the present embodiment, light emitted from the LED elements 21 to 23 to the viewing side and reflected to the rear-face side by the upper surface of the protective layer 50 can be reduced. As a result, leakage of such reflected light to the rear-face side can be more suppressed than in the transparent display device according to the first embodiment.
The configuration is otherwise similar to that of the transparent display device according to the first embodiment.
Note that the present embodiment and the second embodiment can be combined with each other. In other words, the antireflective film 70 shown in
Next, a transparent display device according to a modified example of the third embodiment will be explained with reference to
As shown in
Note that in
Next, a transparent display device according to a fourth embodiment will be explained with reference to
As shown in
The light control layer 90 enables internal transmittance of visible light to be dynamically adjusted. Providing the light control layer 90 enables light emitted from the LED elements 21 to 23 to the viewing side and reflected to the rear-face side to be dynamically prevented from leaking to the rear-face side. As the light control layer 90, for example, a guest-host liquid crystal, a polymer-dispersed liquid crystal, an electroactive anisotropic particle, or an electrochromic material can be used.
For example, the light control layer 90 is transparent when the LED elements 21 to 23 are not emitting light (in other words, when the LED elements 21 to 23 are not displaying an image) and the internal transmittance of visible light in the light control layer 90 is only reduced when the LED elements 21 to 23 are emitting light (in other words, when the LED elements 21 to 23 are displaying an image). According to such a configuration, light emitted from the LED elements 21 to 23 to the viewing side and reflected to the rear-face side can be prevented from leaking to the rear-face side without reducing the internal transmittance of visible light of the transparent substrate 10. Since the internal transmittance of visible light of the transparent substrate 10 is high, visibility of the rear-face side when an image is not displayed increases.
The configuration is otherwise similar to that of the transparent display device according to the first embodiment.
Note that a similar effect can be produced even when a light control layer is formed on the upper surface of the protective layer 50 in the transparent display device shown in
Next, a configuration of a laminated glass according to a fifth embodiment will be explained with reference to
First, a planar configuration of the laminated glass 200 will be explained with reference to
As shown in
As shown in
Note that although
The non-display region 102 is a region which does not include pixels and in which images are not displayed. Wide wirings connected to the power supply line 41, the ground line 42, the row data line 43, and the column data line 44 shown in
Therefore, compared to the display region 101 being transparent, the non-display region 102 is opaque and is visually recognizable from inside a vehicle. When the non-display region 102 is visually recognizable, designability of the laminated glass 200 declines. In consideration thereof, in the laminated glass 200 according to the fifth embodiment, at least a part of the non-display region 102 of the transparent display device 100 is provided in the shielding unit 201. The non-display region 102 provided in the shielding unit 201 is hidden by the shielding unit 201 and is not visually recognizable. Therefore, designability of the laminated glass 200 improves as compared to a case where an entirety of the non-display region 102 is visually recognizable.
Next, a sectional configuration of the laminated glass 200 will be explained with reference to
As shown in
In addition, as shown in
The present invention is not limited to the embodiments described above and can be appropriately modified without deviating from the scope and spirit of the disclosure.
From the disclosure thus described, it will be obvious that the embodiments of the disclosure may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure, and all such modifications as would be obvious to one skilled in the art are intended for inclusion within the scope of the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2020-202483 | Dec 2020 | JP | national |
This application is based upon and claims the benefit of priority from Japanese Patent Application No. 2020-202483 filed on Dec. 7, 2020 and PCT application No. PCT/JP2021/044180 filed on Dec. 2, 2021, the disclosure of which is incorporated herein in its entirety by reference.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2021/044180 | Dec 2021 | US |
| Child | 18325323 | US |
