Vehicle window glass and vehicle structure

Abstract

Provided is a vehicle window glass comprising: a first glass plate having a first major surface; an electrically conductive layer disposed on the first major surface side of the first glass plate; and a slot antenna disposed on the first major surface side of the first glass plate. The slot antenna includes a conductor portion electrically connected to the electrically conductive layer, and a slot surrounded by the conductor portion. The conductor portion has an electric resistance lower than that of the electrically conductive layer. At least a part of the slot overlaps a first region in plan view in which the electrically conductive layer is absent.

Description

[Technical field]

[0001] The present disclosure relates to vehicle glazings and vehicle structures. [Background technology]

[0002] A technique is known for realizing a slot antenna in a vehicle window glass by a slot surrounded by electrodes for passing a direct current through multiple defogger heating wires extending horizontally and conductive wires connected to the multiple defogger heating wires (see, for example, Patent Document 1). Another technique is known for realizing a slot antenna by a slot provided in a bus bar that supplies power to a defogger heater wire (see, for example, Patent Document 2). Furthermore, a technique is known for realizing a slot antenna in a vehicle window glass by a slot opened in a transparent conductive film interposed between laminated glasses (see, for example, Patent Document 3). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2005-080189 A [Patent Document 2] JP 2006-310953 A [Patent Document 3] JP 2006-203331 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, when a conductive layer such as a conductive film is used to realize a slot antenna, it is difficult to realize a slot antenna that can obtain high gain if the conductive layer has a relatively high electrical resistance.

[0005] The present disclosure provides a vehicle window glass and a vehicle structure having a slot antenna that can provide high gain even when a conductive layer having a relatively high electrical resistance is used. [Means for solving the problem]

[0006] The present disclosure relates to a first glass plate having a first major surface; a conductive layer disposed on the first main surface side of the first glass plate; a slot antenna disposed on the first main surface side of the first glass plate, the slot antenna has a conductor portion electrically connected to the conductive layer and a slot surrounded by the conductor portion, the conductor portion has a lower electrical resistance than the conductive layer, A vehicle window glass is provided, wherein at least a portion of the slot overlaps, in a plan view, with a first region that is free of the conductive layer.

[0007] The present disclosure also provides There is also provided a vehicle structure comprising the vehicle window glass and a vehicle body capacitively coupled to the slot antenna. Effect of the Invention

[0008] According to the present disclosure, it is possible to provide a vehicle window glass and a vehicle structure that include a slot antenna that utilizes a conductive layer to obtain high gain. [Brief description of the drawings]

[0009] [Figure 1] 1 is an exploded perspective view showing a configuration example of a vehicle structure including a vehicle window glass in a first embodiment. FIG. [Diagram 2] FIG. 11 is an exploded perspective view showing a configuration example of a vehicle structure including a vehicle window glass according to a second embodiment. [Diagram 3] 13 is a diagram showing a first configuration example in which at least a portion of a slot overlaps a first region without a conductive layer in a plan view. FIG. [Figure 4] 13 is a diagram showing a second configuration example in which at least a portion of the slot overlaps, in a plan view, with a first region having no conductive layer. FIG. [Diagram 5]13 is a diagram showing a third configuration example in which at least a portion of the slot overlaps, in a plan view, with a first region having no conductive layer. FIG. [Figure 6A] FIG. 11 is an exploded perspective view showing a configuration example of a vehicle structure including a vehicle window glass according to a third embodiment. [Figure 6B] FIG. 11 is an exploded perspective view showing a configuration example of a vehicle structure including a vehicle window glass according to a third embodiment. [Figure 7] FIG. 11 is an exploded perspective view showing a configuration example of a vehicle structure including a vehicle window glass according to a fourth embodiment. [Figure 8] 1 is a diagram showing a first configuration example of a slot antenna in a plan view. [Figure 9] FIG. 11 is a diagram showing a second configuration example of the slot antenna in a plan view. [Figure 10] FIG. 2 is a diagram showing, in plan view, an example of the configuration of a simulation model of a vehicle structure including a vehicle window glass. [Figure 11] FIG. 11 is a diagram showing an example of a simulation result of the directivity of a slot antenna. [Figure 12] FIG. 13 is a diagram showing an example of a simulation result of a change in gain with respect to the sheet resistance of a conductive layer. [Figure 13] FIG. 1 is a diagram showing an example of the results of actual measurements of changes in average sensitivity with respect to the slot width a of a slot antenna. [Figure 14] FIG. 13 is a diagram showing an example of change in average sensitivity with respect to the longitudinal length e of the inner conductor in the slot of a slot antenna. [Figure 15] 11 is a diagram showing an example of a change in average sensitivity with respect to the distance between a conductive layer and a conductor portion of a slot antenna. FIG. [Figure 16] FIG. 1 is a diagram showing an example of actual measurement results of average gain in a band of terrestrial digital television broadcast waves. [Figure 17] FIG. 13 is a diagram showing an example of actual measurement results of the directivity of a slot antenna. [Figure 18] 1 is a diagram showing an example of a vehicle structure including a vehicle window glass in a plan view; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment according to the present disclosure will be described with reference to the drawings. For ease of understanding, the scale of each part in the drawings may differ from the actual scale. In directions such as parallel, right angle, orthogonal, horizontal, vertical, up and down, left and right, deviations that do not impair the effects of the embodiment are permitted. The shape of the corners is not limited to right angles, and may be rounded in an arch shape. The X-axis direction, the Y-axis direction, and the Z-axis direction respectively represent directions parallel to the X-axis, the Y-axis direction, and the Z-axis direction. The X-axis direction, the Y-axis direction, and the Z-axis direction are mutually orthogonal. The XY plane, the YZ plane, and the ZX plane respectively represent imaginary planes parallel to the X-axis direction and the Y-axis direction, imaginary planes parallel to the Y-axis direction and the Z-axis direction, and imaginary planes parallel to the Z-axis direction and the X-axis direction.

[0011] In this embodiment, the X-axis direction, the Y-axis direction, and the Z-axis direction respectively represent the left-right direction (horizontal direction) of the glass plate, the up-down direction (vertical direction) of the glass plate, and the direction perpendicular to the surface of the glass plate (also called the normal direction). The X-axis direction, the Y-axis direction, and the Z-axis direction are mutually orthogonal.

[0012] Examples of the vehicle window glass in this embodiment include a rear glass attached to the rear of the vehicle, a windshield attached to the front of the vehicle, a side glass attached to the side of the vehicle, a roof glass attached to the roof of the vehicle, etc. The vehicle window glass is not limited to these examples.

[0013] Fig. 1 is an exploded perspective view showing one configuration example of a vehicle structure including a vehicle window glass in the first embodiment. The vehicle structure 201 shown in Fig. 1 includes a vehicle window glass 101 and a vehicle body section 62 to which the window glass 101 is attached. The vehicle body section 62 is a metal part of the vehicle body, for example, a window frame to which the window glass 101 is attached. In a state in which the window glass 101 is attached to the vehicle body section 62, the positive side in the Z-axis direction represents the vehicle inside side, and the negative side in the Z-axis direction represents the vehicle outside side. Fig. 1 shows the components of the vehicle structure 201 separated in the normal direction of the surface of the glass plate 10.

[0014] The window glass 101 is a single-pane window glass mainly comprising a glass plate 10, a conductive layer 30, and a slot antenna 70. A single-pane window glass refers to a window glass composed of only one glass plate (in this example, the glass plate 10).

[0015] The glass plate 10 is a plate-shaped dielectric having a principal surface 11 facing the positive side in the Z-axis direction and a principal surface 12 facing the side opposite to the principal surface 11 in the Z-axis direction (the negative side in the Z-axis direction). The glass plate 10 may be transparent or translucent. The principal surface 11 is a surface facing the inside of the vehicle, and the principal surface 12 is a surface facing the outside of the vehicle. The glass plate 10 is an example of a first glass plate having a first principal surface, and the principal surface 11 is an example of a first principal surface.

[0016] The conductive layer 30 is a planar conductor on the main surface 11 side of the glass plate 10. The conductive layer 30 may be a conductor in contact with the main surface 11, or may be a conductor disposed on the main surface 11 side via a transparent or semi-transparent dielectric (not shown). The conductive layer 30 may be transparent or semi-transparent. Specific examples of the conductive layer 30 include a metal film such as an Ag (silver) film, a metal oxide film such as an ITO (indium tin oxide) film, a resin film containing conductive particles, and a laminate in which multiple types of films are laminated. The conductive layer 30 may be a resin film such as polyethylene terephthalate coated by deposition or the like.

[0017] The conductive layer 30 may be a conductive film coated on the main surface 11 of the glass plate 10. A specific example of the conductive film is a low-emissivity film such as a Low-E (Low Emissivity) film that exhibits low emissivity performance.

[0018] Low emissivity means reducing heat transfer caused by radiation. A low-emissivity film such as a low-E film ensures heat insulation by suppressing heat transfer caused by radiation. The low-emissivity film may be a general film, for example, a laminated film including a transparent dielectric film, an infrared reflective film, and a transparent dielectric film in this order. Representative examples of transparent dielectric films include metal oxides and metal nitrides. Representative examples of metal oxides include zinc oxide and tin oxide. Representative examples of infrared reflective films include metal films. Representative examples of metal films include silver (Ag). Here, one or more layers of infrared reflective films may be formed between the transparent dielectric films.

[0019] The conductive layer 30 is not limited to a low-emissivity film such as a Low-E film, and may have other functions as long as it is a conductive layer. For example, the conductive layer 30 may have a function of preventing icing or fogging of the window glass 101 by generating heat due to application of a voltage.

[0020] 1, the slot antenna 70 is disposed on the opposite side of the conductive layer 30 from the main surface 11 of the glass plate 10. The slot antenna 70 has a conductor portion 71 electrically connected to the conductive layer 30, and a slot 72 surrounded by the conductor portion 71. The slot antenna 70 may be used as a receiving antenna for receiving radio waves outside the vehicle, such as broadcast waves, or may be used as a wireless communication antenna for transmitting and receiving radio waves to and from communication equipment outside the vehicle.

[0021] The slot antenna 70 is an antenna configured to be capable of receiving radio waves in the UHF (Ultra High Frequency) band, for example, with frequencies of 300 MHz to 3 GHz. A specific example of a frequency band included in the UHF band is the band of terrestrial digital television broadcast waves (for example, 473 MHz to 713 MHz).

[0022] The slot antenna 70 may be an antenna configured to be capable of receiving radio waves in the VHF (Very High Frequency) band with a frequency of 30 MHz to 300 MHz, for example. Specific examples of frequency bands included in the VHF band include the band of FM broadcast waves (for example, 76 MHz to 108 MHz) and the band of DAB Band III (for example, 170 MHz to 240 MHz).

[0023] By arranging the slot antenna 70 so that the longitudinal direction of the slot 72 is substantially perpendicular to the horizontal plane (substantially vertical), the gain when receiving horizontally polarized waves increases, improving the reception sensitivity of the horizontally polarized waves (for example, terrestrial digital television broadcast waves). Alternatively, by arranging the slot antenna 70 so that the longitudinal direction of the slot 72 is substantially parallel to the horizontal plane (substantially horizontal), the gain when receiving vertically polarized waves increases, improving the reception sensitivity of the vertically polarized waves (for example, FM broadcast waves and DAB Band III radio waves).

[0024] The window glass 101 may have a plurality of slot antennas 70. When the window glass 101 has two or more slot antennas 70 at different positions, the longitudinal directions of the slots 72 may be the same or different. For example, the slot antennas 70 may be disposed at the left and right sides of the window glass 101 so that the longitudinal direction of the slots 72 is substantially vertical, or may be disposed at the top and bottom sides of the window glass 101 so that the longitudinal direction of the slots 72 is substantially horizontal. In this case, each slot antenna may be formed to be capable of receiving radio waves of the same frequency band, or may be formed to be capable of receiving radio waves of different frequency bands. In particular, when two or more slot antennas 70 are formed to be capable of receiving radio waves of the same frequency band, a diversity function is obtained. On the other hand, when two or more slot antennas 70 are formed to be capable of receiving radio waves of different frequency bands, the two or more slot antennas 70 function as wideband antennas capable of receiving radio waves of a wide band of frequencies.

[0025] The two slot antennas 70 may be arranged so that the longitudinal directions of the slots 72 are approximately orthogonal to each other. For example, the two slot antennas 70 may be arranged at the left side and the top side of the window glass 101 so that they are capable of receiving radio waves of the same frequency band and the longitudinal directions of the slots 72 are approximately orthogonal to each other. In this case, if the window glass 101 is attached so that its plane is approximately parallel to the vertical direction, any polarized wave arriving from a direction approximately parallel to the horizontal plane direction (for example, any polarized wave of the same frequency band, such as vertically polarized wave, horizontally polarized wave, or circularly polarized wave) can be received. In this case, approximately parallel to the vertical direction refers to a range of ±30° to the vertical direction, but may also be a range of ±15°, ±10°, ±5°, or ±3°. Even if the longitudinal directions of the slots 72 are approximately orthogonal to each other, the two slot antennas 70 may be formed so that they can receive radio waves of different frequency bands.

[0026] The window glass 101 may be attached so that its plane is substantially horizontal. In this case, the term "substantially horizontal" refers to a range of ±30° or less with respect to the horizontal plane, but may also be within ±15°, ±10°, ±5°, or ±3°. An example of the window glass 101 attached so that its plane is substantially horizontal is roof glass. For example, the window glass 101 may be roof glass in which two slot antennas 70 are formed so as to be able to receive radio waves of the same frequency band, and the longitudinal directions of the slots 72 are substantially orthogonal to each other. In this case, the two slot antennas 70 can receive any polarized waves (for example, any polarized waves such as vertically polarized waves, horizontally polarized waves, and circularly polarized waves of the same frequency band) arriving from the vertical direction (zenith direction). In particular, the slot antenna 70 may be formed so as to be able to receive GNSS signals of a predetermined frequency band that are for satellite broadcasting communication and arrive as circularly polarized waves. The predetermined frequency band may be a 1.2 GHz band or a 1.6 GHz band. The 1.2 GHz band may be, for example, 1.226 GHz to 1.228 GHz, and the 1.6 GHz band may be, for example, 1.559 GHz to 1.606 GHz. Furthermore, the slot antenna 70 may be configured to be capable of receiving SDARS (Satellite Digital Audio Radio Service) signals in the S-band (2.320 GHz to 2.345 GHz) of the 2.3 GHz band.

[0027] Furthermore, the window glass 101 may have three or more slot antennas 70, and can be formed as desired according to the polarized waves of the band that can be received. In addition, when the slot antenna 70 has multiple slots 72, the (single) slot antennas 70 in each embodiment can be combined as desired. Hereinafter, the vehicle window glass of this embodiment will be described assuming that the slot antenna 70 has one slot 72, unless otherwise specified.

[0028] The conductor portion 71 is a conductor frame surrounding the slot 72, and the slot 72 is a long and narrow cutout inside the conductor portion 71. The form in which the conductor portion 71 surrounds the slot 72 is not limited to a form in which the slot 72 is completely surrounded by the conductor portion 71, and may include a form in which a minute gap is provided in the conductor portion 71 to connect the outside of the conductor portion 71 with the slot 72. The conductor portion 71 is made of, for example, a metal foil or thin film of copper, silver, or the like.

[0029] At least a portion of the slot 72 overlaps in a planar view with a first region (in this example, the long hole 31 opened in the conductive layer 30) that does not have the conductive layer 30. This makes it possible to prevent radio waves received or transmitted by the slot antenna 70 from being blocked by the conductive layer 30. In terms of preventing the blocking of radio waves, it is preferable that the entire slot 72 overlaps in a planar view with the first region that does not have the conductive layer 30.

[0030] Since the conductor portion 71 is electrically connected to the conductive layer 30, the area of ​​the conductor region through which the high-frequency current generated around the slot 72 flows is expanded, so that the gain of the slot antenna 70 can be increased. The conductor portion 71 is electrically connected to the conductive layer 30 by direct coupling or capacitive coupling. In addition, the conductor portion 71 has a lower electrical resistance than the conductive layer 30. Since the conductor portion 71 has a lower electrical resistance than the conductive layer 30, high-frequency current can easily flow through the conductor portion 71 around the slot 72, so that the gain of the slot antenna 70 can be increased. Therefore, even if a conductive layer 30 with a relatively high electrical resistance is used, it is possible to provide a window glass 101 and a vehicle structure 201 having a slot antenna 70 that can obtain a high gain.

[0031] When the conductive layer 30 has a sheet resistance of 300 [Ω / □ (ohms per square)] or less, the gain of the slot antenna 70 is improved. In terms of improving the gain of the slot antenna 70, the sheet resistance of the conductive layer 30 is preferably 200 [Ω / □] or less, more preferably 100 [Ω / □] or less, and even more preferably 80 [Ω / □] or less. The lower limit of the sheet resistance of the conductive layer 30 may be larger than the sheet resistance of the conductor portion 71, and is, for example, 5 [Ω / □] or more.

[0032] The upper limit of the sheet resistance of the conductor portion 71 should be smaller than the sheet resistance of the conductive layer 30, and is preferably, for example, 2 [Ω / □] or less, and more preferably 1 [Ω / □] or less, in terms of improving the gain of the slot antenna 70. In this way, the magnitude of the electrical resistance of the conductor portion 71 and the conductive layer 30 can be compared using, for example, the sheet resistance as an index.

[0033] When the window glass 101 is attached to the vehicle body 62 at a distance that allows the conductor 71 of the slot antenna 70 to be capacitively coupled to the vehicle body 62, the gain of the slot antenna 70 can be increased. This is because a high-frequency current generated around the slot 72 flows to the vehicle body 62 through the capacitive coupling, and the area of ​​the conductor region through which the high-frequency current flows is expanded. For example, when the coupling capacitance between the conductor 71 of the slot antenna 70 and the vehicle body 62 is 0.4 [pF] or more, the gain of the slot antenna 70 can be increased. In terms of increasing the gain of the slot antenna 70, the lower limit of the coupling capacitance is preferably 1.0 [pF] or more, and more preferably 2.0 [pF] or more. The upper limit of the coupling capacitance is not particularly specified, but can be set to, for example, 35 [pF] or less.

[0034] The window glass 101 may have a light-shielding portion 50 on the main surface 11 side with respect to the glass plate 10. The light-shielding portion 50 is, for example, a light-shielding film that blocks visible light. A specific example of the light-shielding film is ceramics such as a black ceramic film. The light-shielding portion 50 overlaps at least a part of the conductor portion 71 in a plan view, and in the example shown in FIG. 1, it is on the opposite side of the slot antenna 70 from the main surface 11 (more specifically, on the opposite side of the conductive layer 30 from the slot antenna 70). Since the light-shielding portion 50 overlaps at least a part of the conductor portion 71 in a plan view, when the window glass 101 is viewed from the positive side in the Z-axis direction (the vehicle interior side) in the example shown in FIG. 1, the overlapping portion is difficult to see, and therefore the appearance of the window glass 101 and the design of the vehicle is improved.

[0035] 1, at least a portion of the slot 72 overlaps in plan view with a second region without the light-shielding portion 50 (in this example, the opening 51 surrounded by the light-shielding portion 50). This allows the amplifier 60 or the power feed line to be electrically connected to the conductor portion 71 of the slot antenna 70 through the opening 51 even if the slot antenna 70 is not exposed on the surface of the window glass 101 because the slot antenna 70 is sandwiched between the light-shielding portion 50 and the glass plate 10. The amplifier 60, for example, amplifies a signal received by the slot antenna 70 and outputs the amplified signal to a receiving device (not shown).

[0036] The slot antenna 70 may be disposed between the main surface 11 and the conductive layer 30. In this case, the amplifier 60 or the power feed line can be electrically connected to the slot antenna 70 through the opening 51 and the long hole 31. The opening 51 may not be provided. In a configuration without the opening 51, for example, a power feed line such as a flat wire may be electrically connected to the conductor portion 71 of the slot antenna 70 via the end face on the negative side in the X-axis direction of the window glass 101, or the amplifier 60 or the power feed line may be electrically connected to the conductor portion 71 by capacitive coupling in the thickness direction of the light-shielding portion 50.

[0037] Fig. 2 is an exploded perspective view showing an example of a configuration of a vehicle structure including a vehicle window glass in the second embodiment. In the second embodiment, the description of the same configuration as in the above-mentioned embodiment will be omitted by incorporating the above description. The vehicle structure 202 shown in Fig. 2 includes a vehicle window glass 102 and a vehicle body part 62 to which the window glass 102 is attached. The window glass 102 differs from the window glass 101 of the first embodiment in that the light blocking part 50 is arranged between the glass plate 10 and the slot antenna 70 (more specifically, between the conductive layer 30 and the slot antenna 70).

[0038] By disposing the light-shielding portion 50 between the glass plate 10 and the slot antenna 70 (more specifically, between the conductive layer 30 and the slot antenna 70), when the window glass 102 is viewed from the negative side in the Z-axis direction (from the outside of the vehicle), the portion where the conductor portion 71 overlaps with the light-shielding portion 50 becomes difficult to see. This improves the appearance of the window glass 101 and the design of the vehicle.

[0039] The conductor portion 71 of the slot antenna 70 is electrically connected to the conductive layer 30 by capacitive coupling via the light-shielding portion 50. The conductor portion 71 may be electrically connected to the conductive layer 30 by direct coupling via an opening (not shown) formed in the light-shielding portion 50.

[0040] Fig. 3 is a diagram showing a first configuration example in which at least a portion of the slot overlaps with the first region without a conductive layer in a plan view. Fig. 4 is a diagram showing a second configuration example in which at least a portion of the slot overlaps with the first region without a conductive layer in a plan view. Fig. 5 is a diagram showing a third configuration example in which at least a portion of the slot overlaps with the first region without a conductive layer in a plan view. Figs. 3, 4, and 5 all show a configuration in which at least a portion of the conductor portion 71 is on the positive side of the conductive layer 30 in the Z-axis direction.

[0041] In FIG. 3, at least a portion of the slot 72 overlaps in a planar view with a first region (in this example, the long hole 31 surrounded by the conductive layer 30) that does not have the conductive layer 30. The slot 72 may overlap in a planar view with the entire first region. The long hole 31, whose longitudinal direction is in the Y-axis direction, penetrates the conductive layer 30. At least a portion of the conductor portion 71 (in the example of FIG. 3, the entire conductor portion 71) overlaps with the conductive layer 30 in a planar view. The conductor portion 71 may overlap in a planar view with the entire conductive layer 30.

[0042] 4, at least a portion of the slot 72 overlaps in plan view with a first region (in this example, a recess 32 formed on the outer edge of the conductive layer 30) that does not have the conductive layer 30. The slot 72 may overlap the entire first region in plan view. The recess 32, whose longitudinal direction is in the Y-axis direction, is an outer region of the conductive layer 30. At least a portion of the conductor portion 71 overlaps in plan view with the outer edge of the conductive layer 30 that forms the recess 32.

[0043] 5, at least a portion of the slot 72 overlaps a first region (in this example, the peripheral region 33 outside the conductive layer 30) that does not have the conductive layer 30 in a planar view. The slot 72 may overlap the entire first region in a planar view. At least a portion of the conductor portion 71 overlaps the outer edge of the conductive layer 30 in a planar view.

[0044] 3, 4, and 5 show a configuration in which the slot antenna 70 is on the positive side in the Z-axis direction with respect to the conductive layer 30 (the side opposite the main surface 11 of the glass plate 10 with respect to the conductive layer 30). However, the slot antenna 70 may be disposed adjacent to the conductive layer 30 in the same layer. For example, in the configurations shown in FIGS. 3, 4, and 5, the conductor portion 71 may be electrically connected to the conductive layer 30 by direct coupling by contacting the outer edge of the conductive layer 30 in the same layer.

[0045] 6A and 6B are exploded perspective views showing an example of a vehicle structure including a vehicle window glass in the third embodiment. In the third embodiment, the description of the same configuration as in the above-mentioned embodiments will be omitted by incorporating the above description. The vehicle structure 203A shown in FIG. 6A includes a vehicle window glass 103A and a vehicle body section 62 to which the window glass 103A is attached. The window glass 103A differs from the window glasses 101 and 102 of the above-mentioned embodiments in that it has a glass plate 20 on the side where the conductive layer 30 is arranged with respect to the glass plate 10 (more specifically, between the glass plate 10 and the slot antenna 70).

[0046] The window glass 103A is a laminated glass in which a glass sheet 10 arranged on the vehicle exterior side and a glass sheet 20 arranged on the vehicle interior side are bonded together with an interlayer film 40 interposed therebetween.

[0047] The glass plate 20 is a plate-like dielectric having a main surface 21 facing the main surface 11 of the glass plate 10 and a main surface 22 opposite the main surface 21 in the Z-axis direction. The glass plate 20 may be transparent or translucent. The main surface 21 represents the surface facing the outside of the vehicle, and the main surface 22 represents the surface facing the inside of the vehicle. In particular, the main surface 22 corresponds to the outer surface of the laminated glass facing the inside of the vehicle. The glass plate 20 is an example of a second glass plate.

[0048] The intermediate film 40 is a transparent or semi-transparent dielectric material interposed between the glass plate 10 and the glass plate 20. The glass plate 10 and the glass plate 20 are bonded by the intermediate film 40. Examples of the intermediate film 40 include thermoplastic polyvinyl butyral (PVB) and ethylene vinyl acetate copolymer (EVA). The relative dielectric constant of the intermediate film 40 is preferably 2.4 or more and 3.5 or less. The intermediate film 40 may be disposed between the conductive layer 30 and the glass plate 20, or may be disposed between the glass plate 10 and the conductive layer 30. Furthermore, the intermediate film 40 may be disposed both between the conductive layer 30 and the glass plate 20 and between the glass plate 10 and the conductive layer 30.

[0049] 6A, the glass plate 20 is disposed between the conductive layer 30 and the slot antenna 70. The conductor portion 71 of the slot antenna 70 is electrically connected to the conductive layer 30. For example, the conductor portion 71 is electrically connected to the conductive layer 30 by capacitive coupling via the light shielding portion 50, the glass plate 20, and the intermediate film 40. The conductor portion 71 may also be electrically connected to the conductive layer 30 by direct coupling via a flat wire or the like.

[0050] Since the light-shielding portion 50 is between the conductive layer 30 and the slot antenna 70 (more specifically, between the glass plate 20 and the slot antenna 70), when the window glass 102 is viewed from the negative side in the Z-axis direction (the vehicle exterior side), the portion where the conductor portion 71 overlaps with the light-shielding portion 50 is difficult to see. This improves the appearance of the window glass 101 and the design of the vehicle.

[0051] The slot antenna 70 may be located between the light-shielding portion 50 and the glass plate 20 , between the glass plate 20 and the conductive layer 30 , or between the conductive layer 30 and the glass plate 10 .

[0052] The vehicle structure 203B shown in FIG. 6B includes a vehicle window glass 103B and a vehicle body section 62 to which the window glass 103B is attached. The window glass 103B is different from the window glass 103A in that the intermediate film 40 includes an intermediate film 40A and an intermediate film 40B, and a conductive layer 30 is provided between the intermediate film 40A and the intermediate film 40B. In this specification, the intermediate film 40A and the intermediate film 40B are also referred to as the first intermediate film 40A and the second intermediate film 40B, respectively. Furthermore, the conductive layer 30 is not limited to one layer, and may have multiple layers. In other words, the light control film described later is not limited to being provided in a single layer, and may be provided in multiple layers.

[0053] In the window glass 103B, the conductive layer 30 may be a conductive film included in a light control film that can actively change the visible light transmittance of the opening of the window glass 103B by applying an AC voltage. The light control film has, for example, a molecular layer (not shown) having optical anisotropy between a pair of opposing resin substrates (not shown). The main surface of each resin substrate has a conductive film (not shown) and an electrode (not shown) electrically connected to the conductive film. The light control film can be driven by applying a voltage between the pair of conductive layers via the electrodes.

[0054] The resin substrate is made of, for example, a transparent resin. The resin substrate may have, for example, polyethylene terephthalate (PET), polycarbonate (PC), or cycloolefin polymer (COP). In addition, the above-mentioned resins may be used in combination as a pair of opposing resin substrates. The thickness of the resin substrate is, for example, in the range of 5 μm to 500 μm, preferably in the range of 100 μm to 200 μm, and more preferably in the range of 50 μm to 150 μm.

[0055] The conductive film may have, for example, a transparent conductive oxide, a transparent conductive polymer, a laminated film of a metal layer and a dielectric layer, silver nanowires, a metal mesh of silver or copper, etc. The thickness of the conductive film may be, for example, in the range of 200 nm to 2 μm.

[0056] An example of the molecules having optical anisotropy is liquid crystal. That is, for example, a liquid crystal layer may be used as a molecular layer having optical anisotropy. Examples of the liquid crystal layer include polymer dispersed liquid crystal (PDLC), polymer network liquid crystal (PNLC), and guest-host liquid crystal. Alternatively, iodine or the like may be used as the molecules having optical anisotropy. The light control film 30 may have a suspended particle device (SPD) including such a molecular layer.

[0057] Fig. 7 is an exploded perspective view showing one configuration example of a vehicle structure including a vehicle window glass in the fourth embodiment. In the fourth embodiment, the description of the same configuration as in the above-mentioned embodiments will be omitted by citing the above description. A vehicle structure 204 shown in Fig. 7 includes a vehicle window glass 104 and a vehicle body part 62 to which the window glass 104 is attached. The window glass 104 is a laminated glass different from the window glass 103A or 103B of the third embodiment in that it has a glass plate 20 between the glass plate 10 and the conductive layer 30.

[0058] The conductive layer 30 is, for example, a conductive film coated on the main surface 22 of the glass plate 20. Since the light-shielding portion 50 is between the glass plate 10 and the conductive layer 30 (more specifically, between the glass plate 10 and the glass plate 20), when the window glass 102 is viewed from the negative side in the Z-axis direction (the vehicle exterior side), the portion where the conductor portion 71 overlaps with the light-shielding portion 50 is difficult to see. This improves the appearance of the window glass 101 and the design of the vehicle.

[0059] The slot antenna 70 may be located between the conductive layer 30 and the glass plate 20 , between the glass plate 20 and the light-shielding portion 50 , or between the light-shielding portion 50 and the glass plate 10 .

[0060] Fig. 8 is a plan view showing a first configuration example of a slot antenna. A slot antenna 70A shown in Fig. 8 has a conductor portion 71 electrically connected to the conductive layer 30 by capacitive coupling or direct coupling, and a slot 72 surrounded by the conductor portion 71.

[0061] The conductor portion 71 has at least one (two in this example) protruding portion 74 protruding from a middle portion in the longitudinal direction of the slot 72 in the width direction (short direction) of the slot 72 with a width w3. The two protruding portions 74 are located on both sides of a center line 73 that divides the slot 72 in half in the longitudinal direction. One protruding portion 74 protrudes from one middle portion in the longitudinal direction of the conductor portion 71 so as to enter the slot 72, and the other protruding portion 74 protrudes from the other middle portion in the longitudinal direction of the conductor portion 71 so as to enter the slot 72. The two protruding portions 74 protrude in opposite directions. The protruding portion 74 is an electrode (power supply point) electrically connected to the amplifier 60 or the power supply line. When the protruding portion 74 overlaps with a second region (for example, the opening 51 in FIG. 1) without the light shielding portion 50 in a plan view, it becomes easy to electrically connect the protruding portion 74 to the amplifier 60 or the power supply line.

[0062] Here, the wavelength of radio waves in the air in the frequency band received by the slot antenna 70 is λ, the wavelength shortening rate of the glass plate 10 is k, and the length of the slot 72 in the longitudinal direction is the slot length b. In this case, the slot length b is expressed as follows: 1.1×(1 / 2)×λ×k≦b≦2.6×(1 / 2)×λ×k When the above condition is satisfied, the gain of the slot antenna 70 is improved. In terms of improving the gain of the slot antenna 70, the upper limit of the slot length b is as follows: b≦2.5×(1 / 2)×λ×k It is preferable to satisfy b≦2.4×(1 / 2)×λ×k It is more preferable to satisfy b≦2.2×(1 / 2)×λ×k In order to improve the gain of the slot antenna 70, it is more preferable that the slot length b satisfies the following lower limit: 1.0×(1 / 2)×λ×k≦b It is preferable to satisfy 0.9×(1 / 2)×λ×k≦b It is more preferable to satisfy 0.8×(1 / 2)×λ×k≦b It is more preferable that the following conditions are satisfied.

[0063] The wavelength of radio waves in the air in the frequency band received by the slot antenna 70 is λ, the wavelength shortening rate of the glass plate 10 is k, and the length of the slot 72 in the width direction is a slot width a. In this case, the slot width a is expressed as follows: 10mm≦a≦0.15×λ×k When the above condition is satisfied, the gain of the slot antenna 70 is improved. In terms of improving the gain of the slot antenna 70, the slot width a is 10mm≦a≦0.13×λ×k It is preferable to satisfy 10mm≦a≦0.11×λ×k It is more preferable to satisfy the following:

[0064] Fig. 9 is a plan view showing a second configuration example of the slot antenna. The slot antenna 70B shown in Fig. 9 has a conductor 71 electrically connected to the conductive layer 30 by capacitive coupling or direct coupling, and a slot 72 surrounded by the conductor 71. The slot antenna 70B further has an internal conductor 76 in the slot 72 that extends in the longitudinal direction of the slot 72 and does not contact the conductor 71. In Fig. 9, the conductor 71 has only one protrusion 74 that protrudes in the width direction (short direction) of the slot 72 from a middle part in the longitudinal direction of the slot 72.

[0065] If a coaxial line is used as a feeder line connected to a slot antenna, the input to the slot antenna becomes unbalanced, resulting in a decrease in the gain of the slot antenna. In a slot antenna 70B shown in Fig. 9, an internal conductor 76 is provided as an electrode to which the ground of the coaxial line is connected, and is coupled to a conductor portion 71. By electrically connecting the signal line of the coaxial line to the conductor portion 71 and electrically connecting the ground of the coaxial line to the internal conductor 76, the input to the antenna becomes balanced, thereby preventing a decrease in the gain of the slot antenna 70B.

[0066] 9, the internal conductor 76 has a protrusion 75 that protrudes in the width direction of the slot 72. The protrusion 75 protrudes from a longitudinal middle portion of the internal conductor 76 in a direction opposite to the direction in which the protrusion 74 protrudes. The protrusion 75 is an electrode (feed point) that is electrically connected to the amplifier 60 or the ground of the power feed line. When the protrusions 74 and 75 overlap in a plan view with a second region (e.g., the opening 51 in FIG. 1) that does not have the light shielding portion 50, the electrical connection with the amplifier 60 or the power feed line is facilitated.

[0067] Here, the length of the internal conductor 76 in the longitudinal direction of the slot 72 is defined as a conductor length e. In this case, the conductor length e is expressed as follows: 0.01×(1 / 2)×λ×k≦e≦2.00×(1 / 2)×λ×k When the above condition is satisfied, the gain of the slot antenna 70 is improved. In terms of improving the gain of the slot antenna 70, the conductor length e is 0.10×(1 / 2)×λ×k≦e≦1.90×(1 / 2)×λ×k It is preferable to satisfy 0.20×(1 / 2)×λ×k≦e≦1.80×(1 / 2)×λ×k It is more preferable to satisfy the following:

[0068] Fig. 10 is a plan view showing an example of a configuration of a simulation model of a vehicle structure including a vehicle window glass. The vehicle structure model 200 shown in Fig. 10 is a simulation model in which a window glass having a slot antenna 70A and a conductive layer 30 is placed in an opening 64 formed in the center of a planar conductor that represents a vehicle body portion 62.

[0069] Fig. 11 is a diagram showing an example of a simulation result of the directivity of slot antenna 70A using vehicle structure model 200 shown in Fig. 10. Fig. 11 shows the directivity in the ZX plane shown in Fig. 10, which is set as the horizontal plane.

[0070] [Table 1] In Table 1, "coat" refers to the conductive layer 30, and "flange" refers to the vehicle body section 62. "With flange" refers to the case where the slot antenna and the vehicle body section 62 are capacitively coupled. FIG. 11 and Table 1 show examples of simulation results for four vehicle structure models 200A, 200B, 200C, and 200D that differ in the presence or absence of the conductive layer 30 and the vehicle body section 62, for horizontally polarized waves of 600 MHz included in the UHF band. Table 1 shows the average value (average gain) and variance of the gain in 360° directions in the horizontal plane.

[0071] According to Fig. 11 and Table 1, in the case of the vehicle structure model 200A, the average gain was high and the directivity was less biased. In the case of the vehicle structure model 200B, the average gain was high, but the directivity was biased toward the flange side. In the case of the vehicle structure model 200D, the average gain was lower than that of the vehicle structure model 200C, but the directivity was less biased.

[0072] In addition, when measuring Figure 11, the simulation conditions such as the dimensions of each part shown in Figures 8 and 10 are as follows: Opening 64: Rectangle 595mm long x 460mm wide Conductive layer 30: Rectangle of 570mm length x 440mm width Sheet resistance of conductive layer 30: 10Ω / □ Electrical conductivity of the car body portion 62 and the conductor portion 71: ∞S / m (perfect conductor) (Sheet resistance of conductor part 71: 0Ω / □) Distance between the vehicle body 62 and the conductor 71: 5 mm Distance d: 0 mm (the conductor portion 71 and the conductive layer 30 overlap and contact each other) Slot width a: 20mm Slot length b: 290mm w1:10mm w2:10mm w3:5mm It was decided.

[0073] Fig. 12 is a diagram showing an example of a simulation result of a change in gain with respect to the sheet resistance of the conductive layer 30, using the vehicle structure model 200 shown in Fig. 10. The result shows that the gain of the slot antenna 70A increases when the sheet resistance is 500 [Ω / □ (ohms per square)] or less.

[0074] FIG. 13 is a diagram showing an example of the results of actual measurements of the change in average sensitivity versus slot width a of slot antenna 70B in the band of terrestrial digital television broadcast waves (473 MHz to 713 MHz) using an actual vehicle having vehicle structure 210 shown in FIG. 18. FIG. 18 shows the case of a left side glass attached to a window frame (flange 63) formed in vehicle body section 62, as viewed from the inside of the vehicle. During the measurements in FIG. 13, the dimensions of each part of slot antenna 70B (FIG. 9) and vehicle structure 210 (FIG. 18) were as follows: Sheet resistance of conductive layer 30: 10Ω / □ Electrical conductivity of flange 63: 1.0×10 7 S / m(iron) Sheet resistance of conductor portion 71: 0.02Ω / □ (copper foil) Slot width a: variable Slot length b: 290mm Conductor length: 200mm e3:5mm Conductor width f: 3mm w1:10mm w2:10mm Width of protrusion 74 w3: 5mm Distance d: 0 mm (the conductor portion 71 and the conductive layer 30 overlap and contact each other) It was decided.

[0075] 13, the range of the threshold value "-9 dBd" or higher where terrestrial digital television broadcast waves can be received with relatively high sensitivity is a ≧ 9 mm, and the range of the threshold value "-8 dBd" or higher is a ≧ 12 mm.

[0076] Fig. 14 is a diagram showing an example of the results of actual measurements of the change in average sensitivity with respect to the conductor length e of the internal conductor 76 of the slot antenna 70B in the band of terrestrial digital television broadcast waves (473 MHz to 713 MHz) using an actual vehicle having the vehicle structure 210 shown in Fig. 18. During the measurements in Fig. 14, the dimensions of each part of the slot antenna 70B (Fig. 9) and the vehicle structure 210 are as follows: Slot width a: 20mm Conductor length e: Change The other dimensions were the same as those in the measurements shown in FIG.

[0077] 14, the range of e≧20 mm is above the threshold value of "-9 dBd" where digital terrestrial television broadcast waves can be received with relatively high sensitivity. The range of e≧80 mm is above the threshold value of "-8 dBd."

[0078] 15 is a diagram showing an example of the results of actual measurements of the change in average sensitivity with respect to the distance d between the conductive layer 30 and the conductor portion 71 of the slot antenna 70B in the band of terrestrial digital television broadcast waves (473 MHz to 713 MHz) using an actual vehicle having the vehicle structure 210 shown in FIG. 18. During the measurements in FIG. 15, the dimensions of each portion of the slot antenna 70B (FIG. 9) and the vehicle structure 210 were as follows: Slot width a: 20mm Distance d: Change The other dimensions were the same as those in the measurements shown in FIG.

[0079] 15, the range of the threshold value "-9 dBd" or higher, at which digital terrestrial television broadcast waves can be received with relatively high sensitivity, is d≦10 mm. The range of the threshold value "-8 dBd" or higher is d≦5 mm.

[0080] Fig. 16 is a diagram showing an example of the results of actual measurement of the average gain of the band of terrestrial digital television broadcast waves, using an actual vehicle having the vehicle structure 210 shown in Fig. 18. In Fig. 16, "slot frame 10 mm wide" means that the widths w1 and w2 are 10 mm, "slot frame 5 mm wide" means that the widths w1 and w2 are 5 mm, and "film" means the conductive layer 30. The results showed that the average gain of the band of terrestrial digital television broadcast waves was higher when the conductive layer 30 was present than when it was not present.

[0081] Fig. 17 is a diagram showing an example of the results of measuring the directivity of slot antenna 70B in an actual vehicle having vehicle structure 210 shown in Fig. 18. More specifically, Fig. 17 shows the results of measuring the gain in 360° directions in the horizontal plane for horizontally polarized waves of 605 MHz included in the UHF band, with and without conductive layer 30. During the measurement in Fig. 17, the dimensions of each part of slot antenna 70B (Fig. 9) and vehicle structure 210 were as follows: Slot width a: 20mm The other dimensions were the same as those in the measurements shown in FIG.

[0082] According to Figure 17, when the conductive layer 30 is present, the gain is higher on the right side of the vehicle (inside the vehicle) and the front of the vehicle for the slot antenna 70B on the left side window, and the directivity bias is smaller, compared to when the conductive layer 30 is not present.

[0083] Although the embodiments have been described above, the technology of the present disclosure is not limited to the above-described embodiments. Various modifications and improvements, such as combinations with or substitutions for part or all of the other embodiments, are possible.

[0084] This international application claims priority to Japanese Patent Application No. 2020-111790, filed on June 29, 2020, the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0085] 10 Glass Plate 11 Main surface 12 Main surface 20 Glass Plate 30 Conductive layer 31 long hole 32 Dent 33 Surrounding Areas 40,40A,40B Intermediate film 50 Light shielding section 60 Amps 62 Body 63 Flange 64 Opening 70 Slot Antenna 71 Conductor 72 Slots 73 Center line 74,75 Convex 76 Inner conductor 101, 102, 103A, 103B, 104 Window glass 200 Vehicle Structure Model 201, 202, 203A, 203B, 204, 210 Vehicle structure

Claims

1. a first glass sheet having a first major surface; a conductive layer disposed on the first main surface side of the first glass plate; a slot antenna disposed on the first main surface side of the first glass plate, the slot antenna has a conductor portion electrically connected to the conductive layer and a slot surrounded by the conductor portion, the conductor portion has a lower electrical resistance than the conductive layer, At least a portion of the slot overlaps, in a plan view, with a first region that is free of the conductive layer.

2. The vehicle window glass according to claim 1 , wherein the first glass sheet is the only glass sheet that constitutes the vehicle window glass.

3. The vehicle window glass according to claim 1 , further comprising a second glass plate on a side where the conductive layer is disposed relative to the first glass plate.

4. The vehicle window glass according to claim 3 , wherein the second glass sheet is disposed between the first glass sheet and the slot antenna.

5. 5. The vehicle glazing of claim 4, wherein the second glass sheet is disposed between the conductive layer and the slot antenna.

6. 5. The vehicle glazing of claim 4, wherein the second glass sheet is disposed between the first glass sheet and the conductive layer.

7. a light-shielding portion disposed on the first main surface side of the first glass plate; The vehicle window glass according to claim 1 , wherein the light blocking portion overlaps at least a portion of the conductor portion in a plan view.

8. the light-shielding portion is on an opposite side of the slot antenna from the first main surface, The vehicle window glass according to claim 7 , wherein at least a portion of the slot overlaps, in a plan view, with a second region that is free of the light blocking portion.

9. The vehicle window glass according to claim 8 , wherein the second region is a region surrounded by the light blocking portion.

10. The vehicle window glass according to claim 7 , wherein the light blocking portion is disposed between the first glass plate and the slot antenna.

11. The vehicle window glass according to claim 10, wherein the light blocking portion is disposed between the conductive layer and the slot antenna.

12. The vehicle window glass according to claim 10 , wherein the light blocking portion is disposed between the first glass plate and the conductive layer.

13. The vehicle window glass according to claim 1 , wherein the conductive layer has a sheet resistance of 5 Ω / □ or more and 300 Ω / □ or less.

14. The vehicle window glass according to claim 1 , wherein the conductive layer is a low-emissivity film or a conductive film included in a light control film.

15. Let λ be the wavelength of radio waves in the air in a frequency band received by the slot antenna, k be the wavelength shortening rate of the first glass plate, and b be the length of the slot in the longitudinal direction. The slot length b is 1.1×(1 / 2)×λ×k≦b≦2.6×(1 / 2)×λ×k The vehicle window glass according to claim 1 , which satisfies the following:

16. Let λ be the wavelength of radio waves in the air in the frequency band received by the slot antenna, k be the wavelength shortening rate of the first glass plate, and a be the slot width a be the length of the slot in the width direction. The slot width a is 10 mm≦a≦0.15×λ×k The vehicle window glass according to claim 1 , which satisfies the following:

17. The vehicle window glass according to any one of claims 1 to 16, wherein the conductor portion has at least one protrusion protruding in a width direction of the slot from a middle portion in a longitudinal direction of the slot.

18. 18. The vehicle window glass according to claim 1, wherein the slot antenna has an internal conductor within the slot, the internal conductor extending in a longitudinal direction of the slot and not in contact with the conductor portion.

19. When the length of the internal conductor in the longitudinal direction of the slot is a conductor length e, The conductor length e is 0.01×(1 / 2)×λ×k≦e≦2.00×(1 / 2)×λ×k 19. The vehicle window glass according to claim 18,

20. The vehicle window glass according to claim 18 or 19, wherein the internal conductor has a protrusion protruding in a width direction of the slot.

21. The vehicle window glass according to claim 1 , wherein the first region is a region surrounded by the conductive layer.

22. The vehicle window glass according to claim 1 , wherein the slot antenna receives a terrestrial digital television broadcast wave.

23. 22. The vehicle window glass according to claim 1, wherein the slot antenna receives FM broadcast waves or DAB Band III radio waves.

24. 24. The vehicle glazing according to claim 1, wherein the slot antenna is on an opposite side of the conductive layer from the first main surface.

25. A vehicle window glass according to any one of claims 1 to 24, a vehicle body portion capacitively coupled to the slot antenna.

26. 26. The vehicle structure according to claim 25, wherein a coupling capacitance between the slot antenna and the vehicle body portion is 0.4 pF or more.

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