Patent Application
20220131026
The present invention relates to a transparent sensing device, a laminated glass, and a method for manufacturing a transparent sensing device.
A display device using a light emitting diode (LED) element as a pixel is known. Japanese Unexamined Patent Publication No. 2006-301650 discloses, among such display devices, a transparent display device in which the rear side is visible via the display device. As a related technology, a transparent sensing device in which a microsensor is provided on a transparent substrate is known.
The inventors have found the following problems with respect to such a transparent display device and a transparent sensing device.
In such a transparent display device, it is necessary to seal an LED element and a microsensor formed on a transparent substrate and wirings connected to them with a transparent resin. Here, for example, due to moisture contained in the transparent resin or the like, electrochemical migration may occur in the wirings, and the adjacent wirings may be short-circuited. In that case, since at least some LED elements and microsensors do not function normally, there is a problem that the reliability as a transparent display device or a transparent sensing device is inferior.
Hereinafter, “electrochemical migration” is simply referred to as “migration”.
The present invention provides a transparent sensing device having the configuration of [1] below.
[1] A transparent sensing device comprising: a transparent substrate; a microsensor arranged on the transparent substrate and having an area of 250,000 μm2 or less; a plurality of wirings connected to the microsensor; and a sealing layer covering the microsensor arranged on the transparent substrate and the plurality of wirings, wherein the sealing layer is a transparent resin having a water absorption rate of 1% or less after curing.
In one aspect of the present invention,
[2] the transparent sensing device according to [1], wherein a peeling adhesive strength between the sealing layer and the plurality of wirings is 1 N/25 mm or more.
[3] The transparent sensing device according to [1] or [2], wherein a peeling adhesive strength between the sealing layer and the transparent substrate is 1 N/25 mm or more.
[4] The transparent sensing device according to any one of [1] to [3], wherein the transparent resin is any one of an olefin-based resin, an acrylic-based resin, and a silicon-based resin.
[5] The transparent sensing device according to [4], wherein the transparent resin is a cycloolefin polymer or a cycloolefin copolymer.
[6] The transparent sensing device according to [4], wherein the transparent resin is a silicone resin.
[7] The transparent sensing device according to any one of [1] to [6], wherein the distance between adjacent wirings in the plurality of wirings arranged on the transparent substrate is 3 to 100 μm.
[8] The transparent sensing device according to any one of [1] to [7], wherein a voltage applied to the plurality of wirings is 1.5 V or more.
[9] The transparent sensing device according to any one of [1] to [8], wherein the plurality of wirings is a metal containing copper or aluminum as a main component.
[10] The transparent sensing device according to any one of [1] to [9], further comprising: at least one light emitting diode element arranged for each pixel on the transparent substrate and having an area of 10,000 μm2 or less; and a plurality of display wirings connected to the light emitting diode element, the transparent sensing device thus having a display function, wherein the light emitting diode element and the plurality of display wirings are covered with the sealing layer.
[11] The transparent sensing device according to any one of [1] to [10], wherein the transparent sensing device is mounted on a glazing of a vehicle, and the microsensor monitors at least one of an inside and an outside of the vehicle.
[12] A laminated glass comprising: a pair of glass plates; and a transparent sensing device provided between the pair of glass plates, the transparent sensing device comprising: a transparent substrate; a microsensor arranged on the transparent substrate and having an area of 250,000 μm2 or less; a plurality of wirings connected to the microsensor; and a sealing layer covering the microsensor arranged on the transparent substrate and the plurality of wirings, wherein the sealing layer is a transparent resin having a water absorption rate of 1% or less after curing.
[13] The laminated glass according to [12], which is used for a glazing of a vehicle.
[14] The laminated glass according to [13], wherein the microsensor monitors at least one of an inside and an outside of the vehicle.
[15] A method for manufacturing a transparent sensing device, comprising: arranging a microsensor having an area of 250,000 μm2 or less on a transparent substrate; forming a plurality of wirings connected to the microsensor; and forming a sealing layer covering the microsensor arranged on the transparent substrate and the plurality of wirings, wherein the sealing layer is made of a transparent resin having a water absorption rate of 1% or less after curing.
According to the present invention, it is possible to provide a transparent sensing device in which migration of wirings is suppressed and which has excellent reliability.
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 is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiments. In order to clarify the explanation, the following description and drawings are simplified as appropriate.
In the present specification, a “transparent display device” refers to a display device in which visual information such as a person and a background located on the rear side of the display device is visible under a desired usage environment. It should be noted that “whether or not visible” is determined at least in a state where the display device is in a non-display state, that is, in a state where the display device is not energized.
Similarly, in the present specification, the “transparent sensing device” refers to a sensing device in which visual information such as a person and a background located on the rear side of the sensing device is visible under a desired usage environment. The “sensing device” refers to a member capable of acquiring various pieces of information using a sensor.
As used herein, the term “transparent” means that the transmittance of visible light is 40% or more, preferably 60% or more, and more preferably 70% or more. It may also indicate that the transmittance is 5% or more and the haze value is 10 or less. If the transmittance is 5% or more, when the outside is viewed from the room during the daytime, the outside can be seen with the same or higher luminance as in the room, and sufficient visibility can be ensured.
When the transmittance is 40% or more, the rear side of the transparent display device is visible substantially without any problem even if the luminance of the front side and the rear side of the transparent display device is approximately the same. When the haze value is 10 or less, the contrast of the background can be sufficiently secured.
The term “transparent” means that it does not matter whether or not a color is given, that is, it may be colorless and transparent, or it may be colored and transparent.
The transmittance refers to a value (%) measured by a method conforming to ISO9050. The haze value refers to a value measured by a method conforming to ISO14782.
<Configuration of Transparent Display Device>
First, the configuration of a transparent display device according to a first embodiment will be described with reference to
Naturally, the right-handed xyz orthogonal coordinates shown in
As shown in
<Planar Arrangement of Light Emitting Units 20, IC Chips 30, and Wirings 40>
First, with reference to
As shown in
If the pixels are arranged in a predetermined direction at a predetermined pixel pitch, the arrangement format of the pixels PIX, that is, the light emitting units 20 is not limited to the matrix shape.
As shown in
In the example of
Each light emitting unit 20 may include two or more LED elements of similar colors. As a result, the dynamic range of the image can be expanded.
The LED elements 21 to 23 have a small size and are so-called micro LED elements. Specifically, the width (length in the x-axis direction) and the length (length in the y-axis direction) of the LED element 21 on the transparent substrate 10 are both, for example, 100 μm or less, preferably 50 μm or less, more preferably 20 μm or less. The same applies to the LED elements 22 and 23. The lower limit of the width and length of the LED element is, for example, 3 μm or more due to various manufacturing conditions and the like.
Although the dimensions, that is, the width and the length of the LED elements 21 to 23 in
The occupied area of each of the LED elements 21 to 23 on the transparent substrate 10 is, for example, 10,000 μm2 or less, preferably 1,000 μm2 or less, and more preferably 100 μm2 or less. The lower limit of the occupied area of each LED element is, for example, 10 μm2 or more due to various manufacturing conditions and the like. Here, in the present specification, the occupied area of the constituent members such as the LED element and the wiring refers to the area in the xy-plan view in
The shape of the LED elements 21 to 23 shown in
Here, the LED elements 21 to 23 have, for example, a mirror structure for efficiently extracting light to the visible side. Therefore, the transmittance of the LED elements 21 to 23 is as low as about 10% or less, for example. However, in the transparent display device according to the present embodiment, as described above, the LED elements 21 to 23 having a small size having an area of 10,000 μm2 or less are used. Therefore, for example, even when the transparent display device is observed from a short distance of about several tens of centimeters to 2 m, the LED elements 21 to 23 are almost invisible. The region with low transmittance in the display region 101 is small, and the visibility on the rear side is excellent. In addition, the degree of freedom in arrangement of the wirings 40 and the like is large.
The “region with low transmittance in the display region 101” is, for example, a region having a transmittance of 20% or less. The same applies hereinafter.
Further, since the LED elements 21 to 23 having a small size are used, the LED elements are not easily damaged even if the transparent display device is curved. Therefore, the transparent display device according to the present embodiment can be used by being attached to a curved transparent plate such as a glazing for vehicles, or being enclosed between two curved transparent plates. Here, if a flexible material is used as the transparent substrate 10, the transparent display device according to the present embodiment can be curved.
The illustrated LED elements 21 to 23 are chip type, but are not particularly limited. The LED elements 21 to 23 may not be packaged with a resin, or may be entirely or partially packaged. The packaging resin may have a lens function to improve the light utilization rate and the efficiency of extracting light to the outside. In that case, the LED elements 21 to 23 may be packaged separately, or a 3-in-1 chip in which three LED elements 21 to 23 are packaged together may be used. Alternatively, although the LED elements emit light at the same wavelength, light having different wavelengths may be extracted depending on a phosphor or the like contained in the packaging resin.
When the LED elements 21 to 23 are packaged, the dimensions and the area of the above-mentioned LED elements are the dimensions and the area in the packaged state. When three LED elements 21 to 23 are packaged together, the area of each LED element is one-third of the total area.
The LED elements 21 to 23 are, but not particularly limited to, inorganic materials, for example. The red LED element 21 is, for example, AlGaAs, GaAsP, GaP, or the like. The green LED element 22 is, for example, InGaN, GaN, AlGaN, GaP, AlGaInP, ZnSe, or the like. The blue LED element 23 is, for example, InGaN, GaN, AlGaN, ZnSe, or the like.
The luminous efficiency, that is, the energy conversion efficiency of the LED elements 21 to 23 is, for example, 1% or more, preferably 5% or more, and more preferably 15% or more. When the luminous efficiency of the LED elements 21 to 23 is 1% or more, sufficient luminance is obtained even with the small-sized LED elements 21 to 23 as described above, and the LED elements 21 to 23 can be used as a display device even during the daytime. When the luminous efficiency of the LED element is 15% or more, heat generation is suppressed, and the LED element can be easily encapsulated inside a laminated glass using a resin adhesive layer.
The LED elements 21 to 23 are obtained by cutting crystals grown by, for example, a liquid phase growth method, an HVPE (Hydride Vapor Phase Epitaxy) method, an MOCVD (Metal Organic Chemical Vapor Deposition) method, or the like. The obtained LED elements 21 to 23 are mounted on the transparent substrate 10.
Alternatively, the LED elements 21 to 23 may be formed by peeling the same from a semiconductor wafer by micro-transfer printing or the like and transferring the same onto the transparent substrate 10.
The pixel pitches Px and Py are both, for example, 100 to 3000 μm, preferably 180 to 1000 μm, and more preferably 250 to 400 μm. By setting the pixel pitches Px and Py in the above-mentioned range, high transparency can be realized while ensuring sufficient display capability. In addition, it is possible to suppress a diffraction phenomenon that may occur due to light from the rear side of the transparent display device.
The pixel density in the display region 101 of the transparent display device according to the present embodiment is, for example, 10 ppi or more, preferably 30 ppi or more, and more preferably 60 ppi or more.
The area of one pixel PIX can be represented by Px×Py. The area of one pixel is, for example, 1×104 μm2 to 9×106 μm2, preferably 3×104 to 1×106 μm2, and more preferably 6×104 to 2×105 μm2. By setting the area of one pixel to 1×104 μm2 to 9×106 μm2, it is possible to improve the transparency of the display device while ensuring an appropriate display capability. The area of one pixel may be appropriately selected depending on the size of the display region 101, the application, the viewing distance, and the like.
The ratio of the occupied area of the LED elements 21 to 23 to the area of one pixel is, for example, 30% or less, preferably 10% or less, more preferably 5% or less, and further preferably 1% or less. By setting the ratio of the occupied area of the LED elements 21 to 23 to the area of one pixel to 30% or less, the transparency and the visibility on the rear side are improved.
In
As shown in
In the example of
In the example of
The IC chip 30 may be arranged for a plurality of pixels, and drive the plurality of pixels to which each IC chip 30 is connected. For example, if one IC chip 30 is arranged for every four pixels, the number of IC chips 30 can be reduced to ¼ of the example of
The 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. The transmittance of the IC chip 30 is as low as about 20% or less, but using the IC chip 30 having the above-mentioned size, the region with a low transmittance in the display region 101 becomes smaller, and the visibility on the rear side is improved.
The IC chip 30 is, for example, a hybrid IC having an analog region and a logic region. The analog region includes, for example, a current control circuit, a transformer circuit, and the like.
An LED element with an IC chip in which the LED elements 21 to 23 and the IC chip 30 are resin-sealed together may be used. Further, instead of the IC chip 30, a circuit including a thin film transistor (TFT) may be used. The IC chip 30 is not essential.
On the other hand, a microsensor may be mounted on the IC chip 30. That is, the transparent display device according to the present embodiment may be a transparent sensing device. Details of the microsensor will be described later in the fourth embodiment.
The wirings 40 according to the present embodiment are display wirings, and as shown in
In the example of
In each pixel PIX, the power supply line 41 and the column data line 44 are provided on the x-axis negative side of the light emitting unit 20 and the IC chip 30, and the ground line 42 is provided on the x-axis positive side of the light emitting unit 20 and the IC chip 30. Here, the power supply line 41 is provided on the x-axis negative side of the column data line 44. In each pixel PIX, the row data line 43 is provided on the y-axis negative side of the light emitting unit 20 and the IC chip 30.
As will be described in detail later, as shown in
As shown in
In each pixel PIX, the IC chip 30 is arranged on the y-axis negative side of 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 branched from the first power supply branch line 41a in the y-axis negative direction extends linearly and is connected to the x-axis negative side of the end in the y-axis positive side of the IC chip 30.
As shown in
Here, the ground line 42 is connected to the LED elements 21 to 23 via the ground branch line 42a, the IC chip 30, and the drive line 45.
As shown in
Here, the row data line 43 is connected to the LED elements 21 to 23 via the row data branch line 43a, the IC chip 30, and the drive line 45.
As shown in
Here, the column data line 44 is connected to the LED elements 21 to 23 via the column data branch line 44a, the IC chip 30, and the drive line 45.
In each pixel PIX, the drive line 45 connects the LED elements 21 to 23 and the IC chip 30. Specifically, in each pixel PIX, three drive lines 45 are extended in the y-axis direction, and connect the ends on the y-axis negative side of the LED elements 21 to 23 and the end on the y-axis positive side of the IC chip 30.
The arrangement of the power supply line 41, the ground line 42, the row data line 43, the column data line 44, the branch lines thereof, and the drive line 45 shown in
The entire configuration shown in
The row data line 43, the column data line 44, the branch lines thereof, and the drive line 45 are not essential.
The wiring 40 is a metal such as copper (Cu), aluminum (Al), silver (Ag), or gold (Au). Of these, a metal containing copper or aluminum as a main component is preferable from the viewpoint of low resistivity and cost. The wiring 40 may be coated with a material such as titanium (Ti), molybdenum (Mo), copper oxide, or carbon for the purpose of reducing the reflectance. The surface of the coated material may have unevenness.
The width of the wiring 40 in the display region 101 shown in
Here, as shown in
The electrical resistivity of the wiring 40 is, for example, 1.0×10−6 Ωm or less, preferably 2.0×10−8 Ωm or less. The thermal conductivity of the wiring 40 is, for example, 150 to 5,500 W/(m·K), preferably 350 to 450 W/(m·K).
The distance between adjacent wirings 40 in the display region 101 shown in
When the distance between the wirings 40 is not constant due to a curved wiring 40 or the like, the above-mentioned distance between the adjacent wirings 40 indicates the minimum value thereof.
The migration of the wirings 40 is more likely to occur as the electric field strength increases. Here, the electric field strength is defined by “voltage/distance between adjacent wirings 40”. Therefore, the larger the voltage applied to the wiring 40 and the smaller the distance between the adjacent wirings 40, the larger the electric field strength and the easier it is for migration to occur. The voltage applied to the wiring 40 is, for example, 1.5 to 5 V. As described above, when the distance between adjacent wirings 40 is 3 to 100 μm, the maximum electric field strength is about 5 V/3 μm=1,670 kV/m.
The ratio of the occupied area of the wiring 40 to the area of one pixel is, for example, 30% or less, preferably 10% or less, more preferably 5% or less, and further preferably 3% or less. The transmittance of the wiring 40 is as low as 20% or less or 10% or less, for example. However, by setting the ratio of the occupied area of the wiring 40 to 30% or less in one pixel, the region with low transmittance in the display region 101 becomes smaller, and the visibility on the rear side is improved.
The total occupied area of 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.
<Cross-Sectional Configuration of Transparent Display Device>
Next, with reference to
The transparent substrate 10 is a transparent material having an insulating property. In the example of
The main substrate 11 is, for example, a transparent resin, as will be described in detail later.
The adhesive layer 12 is, for example, an epoxy-based, acrylic-based, olefin-based, polyimide-based, or novolac-based transparent resin adhesive.
The main substrate 11 may be a thin glass plate having a thickness of, for example, 200 μm or less, preferably 100 μm or less. The adhesive layer 12 is not essential.
Examples of the transparent resin constituting the main substrate 11 include polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), olefin resins such as cycloolefin polymer (COP) and cycloolefin copolymer (COC), cellular resins such as cellulose, acetyl cellulose and triacetyl cellulose (TAC), imide resins such as polyimide (PI), vinyl resins such as polyethylene (PE), polyvinyl chloride (PVC), polystyrene (PS), polyvinyl acetate (PVAc), polyvinyl alcohol (PVA) and polyvinyl butyral (PVB), acrylic resins such as polymethyl methacrylate (PMMA) and ethylene vinyl acetate copolymer resin (EVA), and urethane resins.
Among the materials used for the main substrate 11, polyethylene naphthalate (PEN) and polyimide (PI) are preferable from the viewpoint of improving heat resistance. Further, cycloolefin polymer (COP), cycloolefin copolymer (COC), polyvinyl butyral (PVB) and the like are preferable in that the birefringence is low and distortion and bleeding of the image seen through the transparent substrate can be reduced.
One of the above-mentioned materials may be used alone, or two or more kinds of materials may be mixed and used. The main substrate 11 may be formed by laminating flat plates of different materials.
The total thickness of the transparent substrate 10 is, for example, 3 to 1000 μm, preferably 5 to 200 μm. The internal transmittance of visible light of the transparent substrate 10 is, for example, 50% or more, preferably 70% or more, and more preferably 90% or more.
The transparent substrate 10 may have flexibility. In this way, for example, the transparent display device can be mounted on a curved transparent plate, or can be used by being sandwiched between two curved transparent plates. Further, it may be a material that shrinks when heated to 100° C. or higher.
As shown in
The total thickness of the wiring 40, that is, the thickness of the first metal layer M1 and the thickness of the second metal layer M2 is, for example, 0.1 to 10 μm, preferably 0.5 to 5 μm. The thickness of the first metal layer M1 is, for example, about 0.5 μm, and the thickness of the second metal layer M2 is, for example, about 3 μm.
Specifically, as shown in
Here, as shown in
Similarly, at the intersection of the column data line 44 and the first power supply branch line 41a shown in
In the example of
As described above, the first power supply branch line 41a is composed of only the first metal layer M1 at the intersection with the column data line 44, and is composed of only the second metal layer M2 in the other portions. Further, 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 is arranged on the metal pad.
The sealing layer 50 is formed on substantially the entire surface of the transparent substrate 10 so as to cover the light emitting units 20, the IC chips 30, and the wirings 40. The sealing layer 50 is a transparent resin having a water absorption rate of 1% or less after curing. The water absorption rate of the transparent resin after curing is more preferably 0.1% or less, and further preferably 0.01% or less. With such a configuration, migration of the wirings 40 due to moisture in the sealing layer 50 is suppressed, and a highly reliable transparent display device can be provided.
The water absorption rate refers to a value (%) measured by a method conforming to the B method of JIS7209.
The transparent resin constituting the sealing layer 50 is, for example, an olefin-based resin such as a cycloolefin polymer (COP) or a cycloolefin copolymer (COC), an acrylic-based resin such as polymethyl methacrylate (PMMA) or an ethylene vinyl acetate copolymer resin (EVA), a silicon-based resin such as a silicone resin. Further, a transparent resin containing no hydroxyl group (OH group) is preferable because it has a low water absorption rate after curing.
The thickness of the sealing layer 50 is, for example, 3 to 1000 μm, preferably 5 to 200 μm.
The internal transmittance of visible light of the sealing layer 50 is, for example, 50% or more, preferably 70% or more, and more preferably 90% or more.
The peeling adhesive strength between the sealing layer 50 and the transparent substrate 10 is preferably 1 N/25 mm or more. The same applies to the peeling adhesive strength between the sealing layer 50 and the wiring 40. Here, the peeling adhesive strength refers to a value measured by a method conforming to JIS K6854-1 (90° peeling).
From the viewpoint of enhancing the adhesion, the difference between the contact angle of water with respect to the transparent substrate 10 and the contact angle of water with respect to the sealing layer 50 is preferably 30° or less. The same applies to the difference between the contact angle of water with respect to the wiring 40 and the contact angle of water with respect to the sealing layer 50. Here, the contact angle of water refers to a value measured by a method conforming to JIS R3257.
Unevenness may be formed on the surface of the transparent substrate 10 or the wiring 40 so that the adhesion is enhanced by the anchor effect. By increasing the adhesion of the sealing layer 50, it is possible to suppress the migration of the wirings 40 due to the moisture entering from the outside.
As described above, in the transparent display device according to the present embodiment, the sealing layer 50 covering the wirings 40 formed on the transparent substrate 10 is a transparent resin having a water absorption rate of 1% or less after curing. Therefore, migration of the wirings 40 due to moisture in the sealing layer 50 is suppressed, and a highly reliable transparent display device can be provided.
<Method for Manufacturing Transparent Display Device>
Next, an example of a method for manufacturing the transparent display device according to the first embodiment will be described with reference to
First, as shown in
The lower layer wiring is not formed at where the power supply line 41, the ground line 42, and the column data line 44 are intersected by the row data line 43.
Next, as shown in
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
<Configuration of Laminated Glass Having Transparent Display Device>
Next, the configuration of a laminated glass according to a second embodiment will be described with reference to
As shown in
Although
The non-display region 102 is a region that does not include pixels and does not display an image. In the non-display region 102, 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, while the display region 101 is transparent, the non-display region 102 is opaque and will be visible from the inside of the vehicle. Here, if the non-display region 102 is visible, the aesthetic appearance of the laminated glass 200 deteriorates. Therefore, in the laminated glass 200 according to the second embodiment, at least a portion of the non-display region 102 of the transparent display device 100 is provided in the shielding portion 201. The non-display region 102 provided in the shielding portion 201 is concealed by the shielding portion 201 and is invisible. Therefore, the aesthetic appearance of the laminated glass 200 is improved as compared with the case where the entire non-display region 102 is visible.
<Configuration of Transparent Display Device>
Next, the configuration of a transparent display device according to a third embodiment will be described with reference to
In the example shown in
In the following description, a case where the transparent display device according to the present embodiment is mounted on the windshield of the glazing of a vehicle will be described. That is, the transparent display device according to the present embodiment can also be applied to the laminated glass according to the second embodiment.
The sensor 70 is, for example, an illuminance sensor (for example, a light receiving element) for detecting illuminance inside and outside the vehicle. For example, the luminance of the display region 101 by the LED elements 21 to 23 is controlled according to the illuminance detected by the sensor 70. For example, the greater the illuminance outside the vehicle than the illuminance inside the vehicle, the greater the luminance of the display region 101 by the LED elements 21 to 23. With such a configuration, the visibility of the transparent display device is further improved.
The sensor 70 may be an infrared sensor (for example, a light receiving element) or an image sensor (for example, a CMOS (Complementary Metal-Oxide-Semiconductor) image sensor) for detecting the line of sight of an observer (for example, a driver). For example, the transparent display device is driven only when the sensor 70 senses the line of sight. For example, the transparent display device is preferably used for the laminated glass shown in
Other configurations are the same as those of the transparent display device according to the first embodiment.
<Configuration of Transparent Sensing Device>
Next, the configuration of a transparent sensing device according to a fourth embodiment will be described with reference to
The sensor 70 is not particularly limited, and is a CMOS image sensor in the transparent sensing device shown in
In the example shown in
The power supply line 41 may be connected to a battery (not shown).
Here,
As shown in
A semiconductor substrate (for example, a silicon substrate) is formed on the wiring layer. The internal wiring IW formed inside the wiring layer connects the wirings 40 (power supply line 41, ground line 42, data output line 46, and control signal line 47) and the photodiodes PD1 to PD3. When the photodiodes PD1 to PD3 are irradiated with light, a current is output from the photodiodes PD1 to PD3. The currents output from the photodiodes PD1 to PD3 are amplified by an amplifier circuit (not shown) and output via the internal wiring IW and the data output line 46.
The color filters CF1 to CF3 are formed on the photodiodes PD1 to PD3 formed inside the semiconductor substrate, respectively. The color filters CF1 to CF3 are, for example, a red filter, a green filter, and a blue filter, respectively.
The microlenses ML1 to ML3 are placed on the color filters CF1 to CF3, respectively. The light collected by the microlenses ML1 to ML3, which are convex lenses, is incident on the photodiodes PD1 to PD3 via the color filters CF1 to CF3, respectively.
The sensor 70 according to the present embodiment is a microsensor having a small size having an occupied area of 250,000 μm2 or less on the transparent substrate 10. In other words, in the present specification, the microsensor is a sensor having a small size having an area of 250,000 μm2 or less in a plan view. The occupied area of the sensor 70 is, for example, preferably 25,000 μm2 or less, more preferably 2,500 μm2 or less. The lower limit of the occupied area of the sensor 70 is, for example, 10 μm2 or more due to various manufacturing conditions and the like.
The shape of the sensor 70 shown in
The transparent sensing device according to the present embodiment can also be applied to the laminated glass according to the second embodiment. When the transparent sensing device according to the present embodiment is mounted on the windshield of the glazing of a vehicle (for example, a vehicle), the sensor 70 can acquire an image of at least one of the inside and outside the vehicle, for example. That is, the transparent sensing device according to the present embodiment has a function as a drive recorder.
The number of sensors 70 in the transparent sensing device according to the fourth embodiment may be singular. The sensor 70 in the transparent sensing device according to the fourth embodiment is not limited to the image sensor, and may be an illuminance sensor, an infrared sensor, or the like exemplified in the third embodiment. The sensor 70 may be a radar sensor, a LIDAR sensor, or the like. For example, the inside and outside of a vehicle can be monitored by a glazing for vehicles equipped with a transparent sensing device using these sensors 70.
That is, the sensor 70 according to the fourth embodiment is not particularly limited as long as it is a microsensor having a small size having an occupied area of 250,000 μm2 or less on the transparent substrate 10. For example, the sensor 70 may be a temperature sensor, an ultraviolet sensor, a radio wave sensor, a pressure sensor, a sound sensor, a speed/acceleration sensor, or the like.
Other configurations are the same as those of the transparent display device according to the first embodiment.
Examples of the present invention are shown below, but the present invention is not construed as being limited to the following examples.
The transparent display devices according to Examples 1 and 2 were subjected to a continuous energization test under high-temperature and high-humidity environment of a temperature of 65° C. and a humidity of 85%, and changes in luminance before and after the test were examined. Examples 1 and 2 are examples of the present invention.
First, a method for manufacturing the transparent display device according to Example 1 will be described with reference to
The method for manufacturing the transparent display device according to Example 1 will be described below.
As shown in
Next, as shown in
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
The water absorption rate of the sealing layer 50 in the transparent display device according to Example 1 was 0.06%.
In the transparent display device according to Example 1, the luminance before the continuous energization test was 181 cd/m2, whereas the luminance after the test was 115 cd/m2, the luminance decrease was only 36%, and the lumen maintenance was 50% or more of the initial value. It is presumed that since the water absorption rate of the sealing layer 50 was low, migration was able to be suppressed.
Next, a method for manufacturing the transparent display device according to Example 2 will be described with reference to
Since the steps shown in
Next, as shown in
Subsequently, the pressure was reduced to 5 Pa or less, and under the reduced pressure, the COP film was heated for 1 hour at 100° C., which is near the glass transition temperature Tg of the COP film, and the COP film was temporarily pressure-bonded to the transparent substrate 10 and the glass plate 60.
The transparent display device according to Example 2 was manufactured by heating in an autoclave device at 10 atm and 130° C. for 20 minutes.
The transparent display device according to Example 2 shown in
The water absorption rate of the sealing layer 50 in the transparent display device according to Example 2 was less than 0.01%.
In the transparent display device according to Example 2, the luminance before the continuous energization test was 121 cd/m2, whereas the luminance after the test was 118 cd/m2, and the luminance decrease was only 2.5%. That is, the lumen maintenance was 95% or more of the initial value, which was an extremely good result. It is presumed that since the water absorption rate of the sealing layer 50 was extremely low, migration was able to be dramatically suppressed.
The present invention is not limited to the above-described embodiments, and can be appropriately modified without departing from the spirit.
For example, the transparent display device may have a touch panel function.
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 |
|---|---|---|---|
| 2019-130927 | Jul 2019 | JP | national |
| 2019-183533 | Oct 2019 | JP | national |
This application is a Continuation of PCT/JP2020/026469 filed on Jul. 6, 2020, which claims the benefit of priority from Japanese Patent Application Nos. 2019-130927 filed on Jul. 16, 2019, and 2019-183533 filed on Oct. 4, 2019. The contents of those applications are incorporated herein by reference in their entireties.
| Number | Date | Country | |
|---|---|---|---|
| Parent | PCT/JP2020/026469 | Jul 2020 | US |
| Child | 17573420 | US |
