Vehicle window glass and vehicle window glass device

Abstract

To provide a vehicle window glass having a conductive layer and capable of transmitting and receiving radio waves in a predetermined frequency band with high gain.SOLUTION: A vehicle window glass includes a first glass plate having a main surface, a conductive layer disposed on the main surface side with respect to the first glass plate, a conductive frame disposed on the main surface side of the first glass plate and having an inner edge along the outer edge of the conductive layer in plan view of the first glass plate, and a power supply unit electrically connected to the conductive frame, and the conductive frame has an electrical resistance lower than that of the conductive layer and functions as part of an antenna that transmits and receives radio waves in a predetermined frequency band.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] The present disclosure relates to a vehicle glazing and a vehicle glazing arrangement. [Background technology]

[0002] Conventionally, in a vehicle windshield having two glass sheets sandwiching polyvinyl butyral (PVB), a low-E coating is disposed between the PVB and the glass sheet on the interior side of the vehicle, and an antenna wire is disposed between the PVB and the glass sheet on the exterior side of the vehicle (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] U.S. Patent No. 7,847,745 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the thickness of an interlayer such as PVB is usually less than 1 mm, and capacitive coupling can occur between the low-E coating and the antenna wire, which are both conductors. Therefore, even if the length of the antenna wire is adjusted, it is not easy to improve the antenna gain if a conductive layer such as a low-E coating is included.

[0005] The present disclosure provides a vehicle window glass and a vehicle window glass device that include a conductive layer and are capable of transmitting and receiving radio waves in a predetermined frequency band with high gain. [Means for solving the problem]

[0006] In one aspect of the present disclosure, a first glass plate having a major surface; a conductive layer disposed on the main surface side of the first glass plate; a conductive frame disposed on the main surface side of the first glass plate, the conductive frame having an inner edge that follows an outer edge of the conductive layer in a plan view of the first glass plate; a power supply portion electrically connected to the conductive frame; Equipped with The conductive frame has a lower electrical resistance than the conductive layer and functions as a part of an antenna that transmits and receives radio waves in a predetermined frequency band, thereby providing a vehicle window glass.

[0007] In another aspect of the present disclosure, There is provided a vehicle glazing arrangement comprising a window frame in which the vehicle glazing is mounted. [Effects of the Invention]

[0008] According to the technique of the present disclosure, it is possible to provide a vehicle window glass and a vehicle window glass device that include a conductive layer and are capable of transmitting and receiving radio waves in a predetermined frequency band with high gain. [Brief explanation of the drawings]

[0009] [Figure 1A] 1 is a plan view showing an example of the configuration of a vehicle window glass device including a vehicle window glass according to a first embodiment. [Figure 1B] 4 is a plan view showing another example of the configuration of a vehicle window glass device including the vehicle window glass according to the first embodiment. FIG. [Figure 1C] 4 is a plan view showing another configuration example of a vehicle window glass device including the vehicle window glass according to the first embodiment. FIG. [Figure 2] 10 is an enlarged plan view illustrating an example of overlap between a conductive layer and a conductive frame. FIG. [Figure 3] 10A and 10B are diagrams illustrating two paths from a power supply portion along the inner edge of a conductive frame to a ground electrode. [Figure 4] FIG. 10 is a plan view showing an example of the configuration of a vehicle window glass device including a vehicle window glass according to a second embodiment. [Figure 5] 10A and 10B are diagrams illustrating two paths from the power supply portion along the inner edge of the conductive frame to the stub. [Figure 6] FIG. 1 is an exploded perspective view showing a first configuration example of a vehicle window glass according to each embodiment. [Figure 7] FIG. 4 is an exploded perspective view showing a second configuration example of the vehicle window glass according to each embodiment. [Figure 8] FIG. 4 is an exploded perspective view showing a third configuration example of the vehicle window glass according to each embodiment. [Figure 9] FIG. 10 is an exploded perspective view showing a fourth configuration example of the vehicle window glass according to each embodiment. [Figure 10] FIG. 10 is an exploded perspective view showing a fifth configuration example of the vehicle window glass according to each embodiment. [Figure 11] FIG. 10 is a diagram showing an example of measurement results of antenna gain obtained in DAB Band III by the vehicle window glass according to each embodiment. [Figure 12] FIG. 10 is a diagram showing an example of measurement results of antenna gain in DAB Band III when the length of L1 (the position where the earth potential is electrically connected) is changed in the vehicle window glass according to the first embodiment. [Figure 13] FIG. 10 is a diagram showing an example of measurement results of antenna gain in DAB Band III when the length of the stub is changed in the vehicle window glass according to the second embodiment. [Figure 14] FIG. 10 is a diagram showing an example of a measurement result of a reflection coefficient S11 obtained in DAB Band III by the vehicle window glass according to each embodiment. [Figure 15] 10A and 10B are diagrams showing an example of measurement results of antenna gain when the overlap between the conductive layer and the conductive frame is changed. DETAILED DESCRIPTION OF THE INVENTION

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

[0011] Examples of the vehicle window glass according to this embodiment include a rear window attached to the rear of a vehicle, a windshield attached to the front of a vehicle, a side window attached to the side of a vehicle, etc. The vehicle window glass is not limited to these examples.

[0012] Fig. 1A is a plan view showing an example of the configuration of a vehicle glazing device equipped with a vehicle window glass according to a first embodiment. The glazing device 201A shown in Fig. 1A includes a vehicle window glass 100A and a conductive window frame 63 to which the window glass 100A is attached. Fig. 1A illustrates the window glass 100A attached to the window frame 63 formed in a vehicle body 62 that is a part of a vehicle 60, as viewed from the inside of the vehicle. With the window glass 100A attached to the window frame 63, the positive side of the Z-axis direction represents the inside of the vehicle, and the negative side of the Z-axis direction represents the outside of the vehicle.

[0013] The vehicle window glass according to this embodiment is particularly suitable for use in a window glass (e.g., a side window) that is installed substantially parallel to a vertical direction perpendicular to a horizontal plane, because it improves the reception sensitivity (antenna gain) of both vertically polarized waves and horizontally polarized waves. Fig. 1A illustrates an example in which the window glass 100A is applied to a side window. The window glass 100A is an example of a window glass for a vehicle side window.

[0014] The window frame 63 is a conductive portion that can be grounded and is also called a flange. The window frame 63 has a frame edge 61 that forms an opening that is covered by the window glass 100A. FIG. 1A shows frame edges 61a, 61b, 61c, and 61d. The frame edge 61 is an example of the inner edge of the window frame 63.

[0015] The window glass 100A is a single-pane window glass mainly comprising a glass plate 10, a conductive layer 30, a conductive frame 70, and a power supply section 80. A single-pane window glass refers to a window glass that is made up of only one glass plate (in this example, the glass plate 10).

[0016] The glass plate 10 is a plate-shaped dielectric having a main surface 11 facing the positive side in the Z-axis direction and a main surface 12 facing the opposite side of the main 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 main surface 11 is the surface facing the inside of the vehicle, and the main surface 12 is the surface facing the outside of the vehicle. The glass plate 10 is an example of a first glass plate having a first main surface, and the main surface 11 is an example of a first main surface.

[0017] The glass plate 10 has an outer peripheral edge 13 including outer edges 13a, 13b, 13c, and 13d. The glass plate 10 is attached to the window frame 63 so that the outer peripheral edge 13 overlaps the window frame 63 in a plan view from inside the vehicle, and the outer edges 13a, 13b, 13c, and 13d are attached to the corresponding frame sides 61a, 61b, 61c, and 61d, respectively. When the glass plate 10 attached to the window frame 63 is viewed from inside the vehicle, the outer edges 13a, 13b, 13c, and 13d are hidden by the vehicle body 62 or the window frame 63, but are shown by solid lines in FIG. 1A for convenience.

[0018] The conductive layer 30 is a planar conductor located 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 of multiple types of films. The conductive layer 30 may also be a resin film such as polyethylene terephthalate coated by vapor deposition or the like.

[0019] 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 radiation performance.

[0020] Low emissivity refers to reducing heat transfer due to radiation. Low emissivity films such as Low-E films ensure thermal insulation by suppressing heat transfer due to 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 another transparent dielectric film in this order. Typical transparent dielectric films are metal oxides and metal nitrides. Typical metal oxides are zinc oxide and tin oxide. Typical infrared reflective films are metal films. Typical metal films are silver (Ag). Here, one or more infrared reflective films may be formed between the transparent dielectric films.

[0021] 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 100A by generating heat when a voltage is applied.

[0022] The conductive frame 70 is a frame-shaped conductor located on the main surface 11 side of the glass plate 10. For example, it may be arranged in the same layer as the conductive layer 30 on the main surface 11 side of the glass plate 10, or it may be arranged on the opposite side of the glass plate 10 from the main surface 11 with respect to the conductive layer 30. The conductive frame 70 may be in contact with the main surface 11, may be arranged on the main surface 11 side with a dielectric (not shown) interposed therebetween, or may be in contact with the conductive layer 30. The conductive frame 70 has an inner edge 71 that follows the outer edge 31 of the conductive layer 30 in a plan view of the glass plate 10. The conductive frame 70 is formed of, for example, copper, silver, or the like.

[0023] The power supply unit 80 is an electrode for power supply and is electrically connected to the conductive frame 70. The power supply unit 80 is provided near the outer peripheral edge 13 of the glass sheet 10 so as to be located near the window frame 63 when the window glass 100A is attached to the window frame 63. The power supply unit 80 is electrically connected to one end of a power supply line 90 or an amplifier via a conductive member such as a connector. The other end of the power supply line 90 or an output terminal of the amplifier is connected to, for example, a communication device such as a receiver. The power supply line 90 is, for example, a coaxial cable having a signal line 91 and a grounding portion 92. The grounding portion 92 may be a shielded wire. One end of the signal line 91 is electrically connected to the power supply unit 80, and one end of the grounding portion 92 is grounded to the vehicle body portion 62 (which may be the window frame 63).

[0024] Power supply unit 80 may protrude outside conductive frame 70 in a plan view of glass plate 10. This makes it easy to bring one end of power supply line 90 (one end of signal line 91) or a conductive member such as a connector that electrically connects an amplifier and power supply unit 80 into contact with power supply unit 80. The shape of power supply unit 80 is preferably a rectangular shape such as a square, an approximately square, a rectangle, or an approximately rectangular shape for implementation, but is not limited to these, and other shapes such as a circle, an approximately circle, an ellipse, or an approximately ellipse may also be used.

[0025] The conductive frame 70 has an inner edge 71 that follows the outer edge 31 of the conductive layer 30, and is therefore electrically connected to the conductive layer 30 via direct or capacitive coupling. Therefore, by attaching the window glass 100A to the conductive window frame 63, the conductive layer 30 and the conductive frame 70 can function as antenna conductors for the patch antenna, and the vehicle body 62 and the window frame 63 can function as grounds for the patch antenna. Because the conductive layer 30 and the conductive frame 70 function as antenna conductors, high-frequency current generated in the conductive frame 70 along the outer edge 31 of the conductive layer 30 can be extracted from the power supply unit 80 electrically connected to the conductive frame 70. Furthermore, since the conductive frame 70 has lower electrical resistance than the conductive layer 30, high-frequency current generated in the conductive frame 70 along the outer edge 31 of the conductive layer 30 can easily flow, thereby improving the antenna gain of a patch antenna that uses the conductive layer 30 and the conductive frame 70 as antenna conductors. An example of an index for evaluating the level of "electrical resistance" referred to here is sheet resistance (unit: Ω / □).

[0026] 1A, the conductive layer 30 and the conductive frame 70 each function as part of a patch antenna that transmits and receives (either transmission or reception, or both) radio waves in a predetermined frequency band. Therefore, even if a conductive layer 30 with relatively high electrical resistance is used, a window glass 100A and a window glass device 201A can be provided that are capable of transmitting and receiving radio waves in a predetermined frequency band with high gain. Furthermore, the width of the conductive frame 70 along the outer edge 31 of the conductive layer 30 may be uniform (constant) or may vary. For example, the width of the conductive frame 70 may be set arbitrarily such that at least a portion of the conductive frame 70 along the frame edge 61d among the frame edges 61a, 61b, 61c, and 61d is wider than the portions along the other frame edges 61a, 61b, and 61c.

[0027] A patch antenna that uses the conductive layer 30 and the conductive frame 70 as antenna conductors is hereinafter also referred to as a "patch antenna PA." The patch antenna PA may be used as a receiving antenna for receiving radio waves outside the vehicle, such as broadcast waves, or as a wireless communication antenna for transmitting and receiving radio waves to and from communication equipment outside the vehicle.

[0028] The patch antenna PA is an antenna configured to be able to transmit and receive radio waves in the UHF (Ultra High Frequency) band, which has a frequency of, for example, 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, 470 MHz to 713 MHz).

[0029] The patch antenna PA may be an antenna configured to transmit and receive radio waves in the VHF (Very High Frequency) band, which has a frequency of 30 MHz to 300 MHz. Specific examples of frequency bands included in the VHF band include the FM broadcast wave band (e.g., 76 MHz to 108 MHz) and the DAB Band III band (e.g., 174 MHz to 240 MHz).

[0030] When the conductive frame 70 has a closed loop shape, high frequency current flows more easily through the conductive frame 70, thereby improving the antenna gain of the patch antenna PA. However, a notch may be formed in part of the conductive frame 70. The shape of the conductive frame 70 is not limited to a substantially rectangular shape, and may be another polygonal shape such as a substantially triangular shape.

[0031] When the power supply section 80 is placed near the corner 73a of the conductive frame 70, it is located near the frame section 70a extending in the X-axis direction (e.g., horizontal direction) and the frame section 70c extending in the Y-axis direction (e.g., up and down direction), thereby improving the antenna gain for both horizontally polarized waves and vertically polarized waves.

[0032] Furthermore, when the power supply unit 80 is disposed near the corner 73a of the conductive frame 70, the electric fields generated at the frame units 70a and 70b facing each other in the Y-axis direction are aligned to the positive or negative side of the Y-axis direction, and the electric fields generated at the frame units 70c and 70d facing each other in the X-axis direction are aligned to the positive or negative side of the X-axis direction. This alignment of the electric field directions improves the radiation efficiency of the patch antenna PA.

[0033] Furthermore, frame portions 70a and 70b extending in the X-axis direction generate an electric field in the Y-axis direction, and frame portions 70c and 70d extending in the Y-axis direction generate an electric field in the X-axis direction. Therefore, by arranging power supply portion 80 near corner portion 73a, it becomes easy to receive electric fields in the X-axis direction and the Y-axis direction, and therefore the antenna gain for both horizontally polarized waves and vertically polarized waves is improved even in an installation environment where window glass 100A is tilted with respect to a horizontal or vertical plane.

[0034] In addition, the power supply portion 80 may be arranged near other corners of the conductive frame 70 (e.g., corner 73b, corner 73c, or corner 73d), and the antenna gain for both horizontally polarized and vertically polarized waves will be improved, as when it is arranged near corner 73a.

[0035] Furthermore, the length of the frame portion 70a extending from the corner portion 73a in the X-axis direction or the opposing distance in the X-axis direction between the frame portion 70c and the frame portion 70d is L X , the distance from the corner 73a in the X-axis direction is D X Then, the vicinity of the corner 73a is defined as 0≦D X / L X ≦0.26. In addition, the length of the frame portion 70c extending from the corner portion 73a in the Y-axis direction or the opposing distance between the frame portion 70a and the frame portion 70b in the Y-axis direction may be defined as L Y , the distance from the corner 73a in the Y-axis direction is D Y Then, the vicinity of the corner 73a is defined as 0≦D Y / L Y The vicinity of other corners of the conductive frame 70 (for example, corner 73b, corner 73c, or corner 73d) may be defined similarly.

[0036] On the other hand, when improving the reception sensitivity for one of the linearly polarized waves, either horizontally polarized waves or vertically polarized waves, the power supply unit 80 may be disposed near the center of each side of the conductive frame 70. For example, if the power supply unit 80 is located at a position that is (-1 / 5+1 / 2)×L in the above definition, X ≦D X ≦(1 / 5+1 / 2)×L X If the above condition is satisfied, the receiving sensitivity (antenna gain) of the horizontally polarized wave can be improved compared to that of the vertically polarized wave.X ≦D X ≦(1 / 6+1 / 2)×L X It is more preferable if the following is satisfied.

[0037] Furthermore, the power supply unit 80 is (-1 / 5+1 / 2)×L Y ≦D Y ≦(1 / 5+1 / 2)×L Y If the above condition is satisfied, the receiving sensitivity (antenna gain) of vertically polarized waves can be improved compared to horizontally polarized waves. Y ≦D Y ≦(1 / 6+1 / 2)×L Y It is more preferable if the following is satisfied.

[0038] When the sheet resistance of the conductive layer 30 is 200 Ω / □ (ohms per square) or less, the gain of the patch antenna PA is improved. In terms of improving the gain of the patch antenna PA, the sheet resistance of the conductive layer 30 is preferably 100 Ω / □ or less, and more preferably 80 Ω / □ or less. The lower limit of the sheet resistance of the conductive layer 30 should be greater than the sheet resistance of the conductive frame 70, and is, for example, 5 Ω / □ or more.

[0039] The upper limit of the sheet resistance of the conductive frame 70 should be smaller than the sheet resistance of the conductive layer 30, and in terms of improving the gain of the patch antenna PA, it is preferable that it be, for example, 2 [Ω / □] or less, and more preferably 1 [Ω / □] or less. In this way, the magnitude of the electrical resistance of the conductive frame 70 and the conductive layer 30 can be compared using, for example, the sheet resistance as an index.

[0040] When the window glass 100A is attached to the vehicle body 62 at a distance that allows capacitive coupling between the conductive frame 70 and the vehicle body 62, the gain of the patch antenna PA can be improved. This is because high-frequency current generated around the conductive frame 70 flows to the vehicle body 62 via this capacitive coupling, expanding the area of ​​the conductor region through which the high-frequency current flows. For example, if the coupling capacitance between the conductive frame 70 of the patch antenna PA and the vehicle body 62 is 0.4 pF or more, the gain of the patch antenna PA can be improved. To increase the gain of the patch antenna PA, 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, 80 pF or less.

[0041] The antenna gain of the patch antenna PA is improved when the frame side 61 of the window frame 63 has a portion that coincides with at least a part of the outer edge 72 of the conductive frame 70 in a plan view of the glass plate 10, or a portion that is located outside at least a part of the outer edge 72 of the conductive frame 70. In the example shown in Fig. 1A, the entire frame side 61 is located outside the entire outer edge 72 in a plan view of the glass plate 10.

[0042] For example, when the opposing distance between the frame side 61 of the window frame 63 and the outer edge 72 of the conductive frame 70 (for example, the opposing distance between the frame side 61b of the window frame 63 and the outer edge 72 of the frame portion 70b) is 0 mm or more and 50 mm or less when viewed in a plane of the glass plate 10, the antenna gain of the patch antenna PA is improved.

[0043] 2 is an enlarged plan view illustrating the overlap between the conductive layer and the conductive frame. When the inner edge 71 of the conductive frame 70 is closer to the outer edge 31 of the conductive layer 30 in a plan view of the glass plate 10, the antenna gain of the patch antenna PA is improved. For example, when at least a portion of the conductive frame 70 overlaps with the conductive layer 30 in a plan view of the glass plate 10 and the outer edge 72 of the conductive frame 70 is located within 10 mm outward from the outer edge 31 of the conductive layer 30, the antenna gain of the patch antenna PA is improved. In this case, the distance d between the outer edge 72 of the conductive frame 70 and the outer edge 31 of the conductive layer 30 is preferably 10 mm or less. Furthermore, from the viewpoint of improving the antenna gain of the patch antenna PA, the distance d is preferably 5 mm or less, and more preferably 1 mm or more.

[0044] Furthermore, when the conductive frame 70 does not overlap the conductive layer 30 in a plan view of the glass plate 10 and the inner edge 71 of the conductive frame 70 is located within 5 mm outward from the outer edge 31 of the conductive layer 30, the antenna gain of the patch antenna PA is improved. In terms of improving the antenna gain of the patch antenna PA, the distance between the inner edge 71 of the conductive frame 70 and the outer edge 31 of the conductive layer 30 is preferably 3 mm or less, and more preferably 1 mm or less. The width of the conductive frame 70 can be designed appropriately regardless of whether it overlaps with at least a portion of the conductive layer 30, and may be, for example, 1 mm to 20 mm, 2 mm to 15 mm, 3 mm to 10 mm, or 3 mm to 7 mm.

[0045] 1A, the conductive frame 70 may have a ground electrode 75 at a location away from the power supply unit 80. The ground electrode 75 is an example of a ground conductor that is equivalent to the ground potential. By adjusting the position of the ground conductor that is electrically connected to the ground potential (for example, the ground potential of the vehicle body unit 62 or the window frame 63), the position of the antinode of the standing wave generated along the conductive frame 70 can be adjusted to the position of the ground conductor. This improves the antenna gain of the patch antenna PA.

[0046] The earth electrode 75 may protrude outside the conductive frame 70 in a plan view of the glass plate 10. This makes it easy to bring a conductive member, such as a connector, that electrically connects the earth potential to the earth electrode 75 into contact with the earth electrode 75. The shape of the earth electrode 75 is preferably a rectangular shape such as a square, an approximately square, a rectangle, or an approximately rectangular shape for implementation, but is not limited to these, and other shapes such as a circle, an approximately circle, an ellipse, or a circular shape such as an approximately ellipse may also be used.

[0047] 3 is a diagram illustrating two paths from the power supply unit 80 along the inner edge of the conductive frame to the earth electrode. Here, the length of the first path from the power supply unit 80 along the inner edge 71 to the earth electrode 75 is L1, and the length of the second path from the power supply unit 80 along the inner edge 71 to the earth electrode 75 is L2. In this example, the first path is a clockwise path from the power supply unit 80, and the second path is a counterclockwise path from the power supply unit 80. Also, let λ be the wavelength in air of radio waves in the frequency band received by the patch antenna PA, k be the wavelength shortening rate of the glass plate 10, and M1 and M2 be integers equal to or greater than 1. In this case, Unlike L1, L2 L1 and L2 are λ / 2×k×M1-λ / 3×k≦L1≦λ / 2×k×M1+λ / 3×k...Formula 1a λ / 2×k×M2-λ / 3×k≦L2≦λ / 2×k×M2+λ / 3×k...Formula 1b If at least one of the above is satisfied, the position of the antinode of the standing wave generated along the conductive frame 70 will approximately coincide with the position of the earth electrode 75, thereby improving the antenna gain of the patch antenna PA. It is more preferable to satisfy both of the above expressions 1a and 1b.

[0048] Note that λ may be the wavelength in air of radio waves of some frequencies included in a predetermined frequency band received by the patch antenna PA, or preferably may be the wavelength in air of radio waves of all frequencies included in the predetermined frequency band W. The same applies to λ in the equations described below.

[0049] Furthermore, L1 and L2 which are different from each other are more preferably λ / 2×k×M1-10 / 31×λ×k≦L1≦λ / 2×k×M1+10 / 31×λ×k...Formula 1c λ / 2×k×M2-10 / 31×λ×k≦L2≦λ / 2×k×M2+10 / 31×λ×k...Formula 1d If at least one of the above is satisfied, the position of the antinode of the standing wave generated along the conductive frame 70 will approximately coincide with the position of the earth electrode 75, thereby improving the antenna gain of the patch antenna PA. It is more preferable to satisfy both of the above expressions 1c and 1d.

[0050] Furthermore, L1 and L2, which are different from each other, are more preferably: λ / 2×k×M1-5 / 16×λ×k≦L1≦λ / 2×k×M1+5 / 16×λ×k ··· Formula 1e λ / 2×k×M2-5 / 16×λ×k≦L2≦λ / 2×k×M2+5 / 16×λ×k...Formula 1f If at least one of the above is satisfied, the position of the antinode of the standing wave generated along the conductive frame 70 will approximately coincide with the position of the earth electrode 75, thereby improving the antenna gain of the patch antenna PA. It is even more preferable if both of the above expressions 1e and 1f are satisfied.

[0051] Fig. 1B is a plan view showing another configuration example of a vehicle window glass device equipped with a vehicle window glass according to the first embodiment. A window glass device 201B shown in Fig. 1B differs from window glass device 201A in that it has a cutout portion 15, where a part of the conductive frame 70 is cut away. The cutout portion 15 may be provided in only one of the two paths (clockwise / counterclockwise) of the conductive frame 70 from the power supply unit 80 to the earth electrode 75, and the number of cutout portions 15 may be one or more.

[0052] For example, the window glass device 201B may satisfy either one of the above formulas 1a and 1b, preferably either one of formulas 1c and 1d, and more preferably either one of formulas 1e and 1f. When the window glass device 201B has a notch 15 in either L1 or L2, as in the case of the window glass device 201B, it is preferable that the path that does not have the notch 15 satisfies either one of the above formulas.

[0053] Fig. 1C is a plan view showing another configuration example of a vehicle glazing device equipped with a vehicle window glass according to the first embodiment. A window glass device 201C shown in Fig. 1C differs from window glass device 201A in that the conductive frame 70 has a ground electrode 85 at a location away from the power supply unit 80. In other words, the conductive frame 70 has a plurality of ground electrodes, namely, a ground electrode 75 (first ground electrode) and a ground electrode 85 (second ground electrode). The first ground electrode 75 is also referred to as a first ground conductor portion 75, and the second ground electrode 85 is also referred to as a second ground conductor portion 85.

[0054] In the glazing device 201C shown in FIG. 1C, the length of the first path (clockwise) from the power supply unit 80 along the inner edge 71 of the conductive frame 70 to the earth electrode 75 is given as L1, and the length of the second path (counterclockwise) from the power supply unit 80 along the inner edge 71 of the conductive frame 70 to the earth electrode 85 is given as L2. These lengths L1 and L2 need only satisfy at least one of the above formulas 1a and 1b, preferably at least one of formulas 1c and 1d, and more preferably at least one of formulas 1e and 1f. In this way, in the glazing device 201C, the lengths from the power supply unit 80 to the earth electrode (first earth electrode 75 or second earth electrode 85) that are the shortest of the two clockwise and counterclockwise paths along the inner edge 71 of the conductive frame 70 are given as lengths L1 and L2, respectively. Therefore, the window glass device 201C can set preferred lengths L1 and L2 without depending on the length of the conductive frame 70, and therefore the resonant frequency can be set arbitrarily, thereby improving the receiving sensitivity (antenna gain) in the desired frequency band.

[0055] FIG. 4 is a plan view showing a configuration example of a vehicle glazing device including a vehicle window glass according to the second embodiment. In the second embodiment, the same configuration and effects as those of the first embodiment will be omitted by incorporating the above description. The glazing device 202 shown in FIG. 4 includes a vehicle window glass 100B and a conductive window frame 63 to which the window glass 100B is attached. Instead of a ground conductor such as the earth electrode 75 of the first embodiment, the conductive frame 70 includes a stub 76 having an open end 76b connected to a location away from the power supply unit 80. By adjusting the position of the electrical connection point 76a between the stub 76 and the conductive frame 70 and the length of the stub 76, the position of the antinode of the standing wave generated along the conductive frame 70 can be adjusted to the position of the connection point 76a. This improves the antenna gain of the patch antenna PA.

[0056] 5 is a diagram illustrating two paths from the power feed point along the inner edge of the conductive frame to the stub. The length of the first path from the power feed point 80 along the inner edge 71 to the stub 76 is L1, and the length of the second path from the power feed point 80 along the inner edge 71 to the stub 76 is L2. In this example, the first path is the path from the power feed point 80 to the connection point 76a in a clockwise direction, and the second path is the path from the power feed point 80 to the connection point 76a in a counterclockwise direction. Also, let λ be the wavelength in air of radio waves in the frequency band received by the patch antenna PA, k be the wavelength shortening rate of the glass plate 10, and N1 and N2 be integers equal to or greater than 1. In this case, Unlike L1, L2 L1 and L2 are λ / 2×k×N1-λ / 3×k≦L1≦λ / 2×k×N1+λ / 3×k...Formula 2a λ / 2×k×N2-λ / 3×k≦L2≦λ / 2×k×N2+λ / 3×k...Formula 2b If at least one of the above is satisfied, the position of the antinode of the standing wave generated along the conductive frame 70 will approximately coincide with the position of the connection point 76a, thereby improving the antenna gain of the patch antenna PA. It is more preferable to satisfy both of the above expressions 2a and 2b.

[0057] Furthermore, L1 and L2 which are different from each other are more preferably λ / 2×k×M1-10 / 31×λ×k≦L1≦λ / 2×k×M1+10 / 31×λ×k...Formula 2c λ / 2×k×M2-10 / 31×λ×k≦L2≦λ / 2×k×M2+10 / 31×λ×k Equation 2d If at least one of the above is satisfied, the position of the antinode of the standing wave generated along the conductive frame 70 will approximately coincide with the position of the connection point 76a, thereby improving the antenna gain of the patch antenna PA. It is more preferable to satisfy both of the above expressions 2c and 2d.

[0058] Furthermore, L1 and L2, which are different from each other, are more preferably: λ / 2×k×M1-5 / 16×λ×k≦L1≦λ / 2×k×M1+5 / 16×λ×k...Formula 2e λ / 2×k×M2-5 / 16×λ×k≦L2≦λ / 2×k×M2+5 / 16×λ×k...Formula 2f If at least one of the above is satisfied, the position of the antinode of the standing wave generated along the conductive frame 70 will approximately coincide with the position of the connection point 76a, thereby improving the antenna gain of the patch antenna PA. It is even more preferable if both of the above expressions 2e and 2f are satisfied.

[0059] Let D be the length of the stub 76, λ be the wavelength in the air of the radio wave in the frequency band received by the patch antenna PA, k be the wavelength shortening rate of the glass plate 10, and P be an integer equal to or greater than 1. In this example, the length D is the path length from the connection point 76a to the open end 76b. In this case, D is expressed as follows: λ / 4×k×(2×P-1)-λ / 6×k≦D≦λ / 4×k×(2×P-1)+λ / 6×k...Formula 3a If the above equation is satisfied, the stub 76 effectively functions as a "λ / 4 stub", thereby improving the antenna gain of the patch antenna PA.

[0060] D is more preferably λ / 4×k×(2×P-1)-λ / 7×k≦D≦λ / 4×k×(2×P-1)+λ / 7×k...Formula 3b If the above equation is satisfied, the stub 76 functions more effectively as a "λ / 4 stub", thereby improving the antenna gain of the patch antenna PA.

[0061] Furthermore, D is more preferably λ / 4×k×(2×P-1)-λ / 8×k≦D≦λ / 4×k×(2×P-1)+λ / 8×k...Formula 3c If the above equation is satisfied, the stub 76 functions more effectively as a "λ / 4 stub", thereby improving the antenna gain of the patch antenna PA.

[0062] When the width W of the stub 76 is 0.5 mm or more and 20 mm or less, the antenna gain of the patch antenna PA is improved. If the width W is less than 0.5 mm, manufacturing becomes difficult, and if it exceeds 20 mm, it becomes difficult to miniaturize the patch antenna PA. From the viewpoint of improving the antenna gain of the patch antenna PA, the width W is preferably 1 mm or more and 18 mm or less.

[0063] 6 to 10 are exploded views showing examples of the configuration of vehicle window panes according to the respective embodiments. The window panes 100A and 100B may have any of the layered structures shown in FIGS.

[0064] 6 to 10, the window glasses 101 to 105 may each have a light-shielding portion 50 located on the main surface 11 side of the glass plate 10. The light-shielding portion 50 is, for example, a light-shielding film that blocks visible light. Specific examples of light-shielding films include ceramics such as a black ceramic film. The light-shielding portion 50 overlaps at least a portion of the conductive frame 70 in a plan view of the glass plate 10. This makes it difficult to see the overlapping portion when viewing the window glass 101 from the Z-axis direction (from the outside or inside of the vehicle), thereby improving the appearance of the window glass 101 and the design of the vehicle.

[0065] In the examples shown in Figures 6 and 8 to 10, the light-shielding portion 50 is disposed between the glass plate 10 and the conductive frame 70. As shown in Figures 6 and 8, the light-shielding portion 50 may be disposed between the conductive layer 30 and the conductive frame 70. As shown in Figure 7, the conductive frame 70 may be disposed between the light-shielding portion 50 and the conductive layer 30. The light-shielding portion 50 may also be disposed between the glass plate 10 and the conductive layer 30 (for example, in Figure 9, a configuration in which the glass plate 20 and the intermediate film 40 are not present).

[0066] Furthermore, as shown in FIGS. 8 to 10 , the window glasses 103, 104, 105 may include a glass plate 20 on the side of the glass plate 10 where the conductive layer 30 is disposed. The glass plate 20 is an example of a second glass plate. In FIG. 8 , the glass plate 20 is disposed between the glass plate 10 and the conductive frame 70. In FIG. 9 , the glass plate 20 is disposed between the conductive layer 30 and the conductive frame 70. In FIG. 10 , the glass plate 20 is disposed between the glass plate 10 and the conductive layer 30.

[0067] Fig. 11 shows an example of measurement results of antenna gain obtained in DAB Band III using vehicle window panes according to each embodiment. Fig. 11 shows the cases of a window pane 100A (see Fig. 1) having an earth electrode 75 electrically connected to earth potential, a window pane 100B (see Fig. 4) having a stub 76, and a window pane 100A (referred to as "window pane 100") not having an earth electrode 75 electrically connected to earth potential. The window pane 100 improves antenna gain in a relatively low frequency band. The window panes 100A and 100B improve antenna gain across the entire DAB Band III frequency band.

[0068] The conditions for the dimensions of each part of the antenna when measuring Figure 11 are as follows: L1: 930 [mm] L2: 1000 [mm] D: 260 [mm] W: 5 [mm] d:5[mm] Sheet resistance of conductive layer 30: 10 [Ω / □] Sheet resistance of conductive frame 70: 0.02 [Ω / □] The wavelength in air for DAB Band III is λ=1249 mm to 1723 mm, and the wavelength shortening rate of the window glass (glass plate 10) is k=0.67, and N1=N2=2. Assuming this, the dimensions L1 and L2 measured in FIG. 11 satisfied the above formulas 2a, 2c, 2e, 2b, 2d, and 2f for all wavelengths λ (=1249 mm to 1723 mm). Furthermore, with P=1, the dimension D measured in FIG. 11 satisfied the above formulas 3a, 3b, and 3c for all wavelengths λ (=1249 mm to 1723 mm).

[0069] 12 is a diagram showing an example of measurement results of antenna gain in DAB Band III when the length of L1 (the position where the earth potential is electrically connected) is changed in the vehicle window glass (window glass 100A) according to the first embodiment. L1 represents the length of the first path from the power supply unit 80 along the inner edge 71 of the conductive frame 70 to the earth electrode 75. L1 = 930 mm represents the case where the earth electrode 75 is located almost diagonally from the power supply unit 80. Setting L1 = 930 mm resulted in a flat frequency characteristic.

[0070] The conditions for the dimensions of each part of the antenna during the measurement in Figure 12, except for L1, were the same as those described above during the measurement in Figure 11. In particular, when L1 = 930 mm and L1 = 980 mm, the above formulas 2a, 2c, and 2e were satisfied for all wavelengths λ (= 1249 mm to 1723 mm).

[0071] 13 is a diagram showing an example of measurement results of antenna gain in DAB Band III when the stub length D is changed in the vehicle window glass (window glass 100B) according to the second embodiment. The antenna gain was particularly improved by setting D=260 mm.

[0072] The conditions for the dimensions of each part of the antenna during the measurement in Figure 13 were the same as those described above for the measurement in Figure 11, except for D. When D = 120 mm to 300 mm, the above formula 3a was satisfied at all wavelengths λ (= 1249 mm to 1723 mm), and when D = 180 mm to 300 mm, formulas 3a, 3b, and 3c were satisfied at all wavelengths λ (= 1249 mm to 1723 mm). Furthermore, when D = 0 mm and M1 = 2, the dimensions of L1 (= 930 mm) and L2 (= 1000 mm) satisfied formulas 1a, 1c, 1e, 1b, 1d, and 1f at all wavelengths λ (= 1249 mm to 1723 mm).

[0073] Fig. 14 is a diagram showing an example of a simulation result of the reflection coefficient S11 obtained in the DAB Band III band by the vehicle window glass according to each embodiment. Fig. 14 shows the cases of a window glass 100A (see Fig. 1) having a ground electrode 75 electrically connected to a ground potential, a window glass 100B (see Fig. 4) having a stub 76, and a window glass 100A (referred to as "window glass 100") not having a ground electrode 75 electrically connected to a ground potential. With the window glass 100, matching was obtained in the vicinity of 175 MHz on the lower side of the DAB Band III band. With the window glasses 100A and 100B, matching was obtained in the range of 200 MHz to 210 MHz, which is closer to the center of the DAB Band III band.

[0074] The conditions for the dimensions of each part of the antenna during the simulation in Figure 14 are as follows: L1: 845 [mm] L2: 1265 [mm] D: 200 [mm] W: 5 [mm] d:5[mm] Sheet resistance of conductive layer 30: 10 [Ω / □] Sheet resistance of conductive frame 70: 0 [Ω / □] The dimensions of L1 in the simulation satisfied the above formulas 2a, 2c, and 2e for all wavelengths λ (= 1249 mm to 1723 mm), and the dimensions of D satisfied formulas 3a, 3b, and 3c for all wavelengths λ (= 1249 mm to 1723 mm).

[0075] FIG. 15 shows an example of simulation results for antenna gain when the overlap between the conductive layer and the conductive frame is varied. In FIG. 2, the size of the conductive frame 70 (frame width: 5 mm) is fixed, and the size of the conductive layer 30 is varied. When d = 0, the outer edge of the conductive frame 70 and the outer edge of the conductive layer 30 are the same size, and the overlap width between the conductive frame 70 and the conductive layer 30 is 5 mm. As shown in FIG. 15, when d = 0, the antenna gain is low. Reducing the conductive layer 30 and increasing the distance d increases the antenna gain. When the conductive layer 30 is further reduced, the antenna gain begins to drop at d = 4 mm (overlap width: 1 mm). The distance d at which the antenna gain drops 2 dB from its peak is 8.3 mm (when the outer edge 31 is 3.3 mm inward from the inner edge 71), and the distance d at which the antenna gain drops 3 dB is 10.1 mm (when the outer edge 31 is 5.1 mm inward from the inner edge 71).

[0076] Although the embodiments have been described above, the technology of the present disclosure is not limited to the above-described embodiments, and various modifications and improvements are possible, such as combinations with or substitutions for part or all of other embodiments. [Explanation of symbols]

[0077] 10 Glass Plate 11 Main surface 12 Main Surfaces 13a, 13b, 13c, 13d outer edge 15 Cutout 20 Glass Plate 30 Conductive layer 31 outer edge 40 Interlayer 50 Light blocking section 60 vehicles 61 Frame side 62 Body 63 Window Frame 70 Conductive Frame 71 Common-law marriage 72 outer edge 73a,73b,73c,73d corner 75,85 Earth electrode 76 Stub 80 Power supply unit 90 Power line 91 Signal line 92 Grounding part 100A, 100B, 101, 102, 103, 104, 105 Window glass 201A, 201B, 201C, 202 Window glass device

Claims

1. a first glass plate having a major surface; a conductive layer disposed on the main surface side of the first glass plate; a conductive frame disposed on the main surface side of the first glass plate, the conductive frame having an inner edge along an outer edge of the conductive layer in a plan view of the first glass plate; a power supply portion electrically connected to the conductive frame; Equipped with the conductive frame has a lower electrical resistance than the conductive layer and functions as a part of an antenna that transmits and receives radio waves in a predetermined frequency band; the conductive frame has a ground conductor portion at a location away from the power supply portion, the ground conductor portion being equivalent to a ground potential; Let L 1 be the length of a first path from the power supply portion along the inner edge to the ground conductor portion, L 2 be the length of a second path from the power supply portion along the inner edge to the ground conductor portion, λ be the wavelength in air of radio waves in the frequency band, k be the wavelength shortening rate of the first glass plate, and M 1 and M 2 be integers of 1 or greater. L 2 is different from L 1 ; L 1 and L 2 are λ / 2×k×M 1 −λ / 3×k≦L 1 ≦λ / 2×k×M 1 +λ / 3×k, λ / 2×k×M 2 −λ / 3×k≦L 2 ≦λ / 2×k×M 2 +λ / 3×k, A vehicle window glass that satisfies at least one of the above requirements.

2. The length L of the first path １ is the length from the power supply part to the first ground conductor part, and the length L of the second path ２ The vehicle window glass according to claim 1 , wherein λ is a length from the power supply portion to the second ground conductor portion.

3. A first glass plate having a main surface; a conductive layer disposed on the main surface side of the first glass plate; a conductive frame disposed on the main surface side of the first glass plate, the conductive frame having an inner edge along an outer edge of the conductive layer in a plan view of the first glass plate; a power supply portion electrically connected to the conductive frame; Equipped with the conductive frame has a lower electrical resistance than the conductive layer and functions as a part of an antenna that transmits and receives radio waves in a predetermined frequency band; The conductive frame includes a stub connected to a location remote from the power supply portion and having an open end.

4. The length of the first path from the feeding point along the inner edge to the stub is L １ , the length of the second path from the feeding portion along the inner edge to the stub is L ２ , the wavelength in the air of the radio wave of the frequency band is λ, the wavelength shortening rate of the first glass plate is k, N １ and N ２ When is an integer greater than or equal to 1, L ２ Is, L １ Unlike L １ and L ２ teeth, λ / 2×k×N １ -λ / 3×k≦L １ ≦λ / 2×k×N １ +λ / 3×k, λ / 2×k×N ２ -λ / 3×k≦L ２ ≦λ / 2×k×N ２ +λ / 3×k, 4. The vehicle window glass according to claim 3, which satisfies at least one of the above requirements.

5. When the length of the stub is D, the wavelength in the air of the radio wave in the frequency band is λ, the wavelength shortening rate of the first glass plate is k, and P is an integer of 1 or more, D is expressed as follows: λ / 4×k×(2×P−1)−λ / 6×k≦D≦λ / 4×k×(2×P−1)+λ / 6×k, 5. The vehicle window glass according to claim 3, which satisfies the following:

6. 6. The vehicle window glass according to claim 3, wherein the stub has a width of 0.5 mm or more and 20 mm or less.

7. The vehicle window glass according to claim 1 , wherein the power supply portion is arranged near a corner of the conductive frame.

8. The vehicle window glass according to claim 1 or 2, wherein the power supply portion is disposed near a center of a side of the conductive frame.

9. The vehicle window glass according to claim 1 , further comprising a second glass plate disposed on a side of the first glass plate on which the conductive layer is disposed.

10. The vehicle window glass according to claim 9 , wherein the second glass plate is disposed between the first glass plate and the conductive frame.

11. The vehicle window glass according to claim 10, wherein the second glass sheet is disposed between the conductive layer and the conductive frame.

12. 11. The vehicle glazing according to claim 10, wherein the second glass sheet is disposed between the first glass sheet and the conductive layer.

13. The vehicle window glass according to claim 1 , wherein the first glass plate is the only glass plate constituting the vehicle window glass.

14. The vehicle window glass according to claim 1 , wherein the conductive frame is arranged on an opposite side of the conductive layer from the main surface.

15. 15. The vehicle glazing according to any one of claims 1 to 14, wherein the conductive frame has a closed loop shape.

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

17. The vehicle window glass according to any one of claims 1 to 16, wherein the conductive layer has a sheet resistance of 5 [Ω / □] or more and 200 [Ω / □] or less.

18. 18. A vehicle glazing according to any one of the preceding claims, wherein the conductive layer is a low-emissivity film.

19. The vehicle window glass according to claim 1 , wherein the power supply portion protrudes outside the conductive frame in a plan view of the first glass plate.

20. The vehicle window glass according to claim 1 , wherein an outer edge of the conductive frame is located outside an outer edge of the conductive layer in a plan view of the first glass plate.

21. 21. The vehicle window glass according to claim 20, wherein, in a plan view of the first glass plate, at least a portion of the conductive frame overlaps the conductive layer, and an outer edge of the conductive frame is located within 10 mm outward from an outer edge of the conductive layer.

22. 21. The vehicle window glass according to claim 20, wherein, in a plan view of the first glass plate, the conductive frame does not overlap the conductive layer, and an inner edge of the conductive frame is located within 5 mm outward from an outer edge of the conductive layer.

23. 23. A vehicle glazing according to any one of claims 1 to 22, wherein the frequency band is the VHF band.

24. 23. A vehicle window glass according to any one of claims 1 to 22, wherein the frequency band is the UHF band.

25. 25. Vehicle glazing according to any one of claims 1 to 24 for use as a side glass of a vehicle.

26. A vehicle glazing device comprising: a vehicle glazing according to any one of claims 1 to 25; and an electrically conductive window frame to which the vehicle glazing is attached.

27. 27. The vehicle window glass device according to claim 26, wherein an inner edge of the window frame has a portion that coincides with at least a part of an outer edge of the conductive frame in a plan view of the first glass plate, or a portion that is located outside at least a part of the outer edge of the conductive frame.

28. 28. The vehicle window glass device according to claim 27, wherein an opposing distance between an inner edge of the window frame and an outer edge of the conductive frame is 0 mm or more and 50 mm or less in a plan view of the first glass plate.

Images