JP7735877B2 - Vehicle window glass - Google Patents

Description

The present invention relates to a vehicle window glass.

It is known that antennas capable of receiving radio waves in various broadcast frequency bands, such as AM broadcast waves, FM broadcast waves, European standard DAB (Digital Audio Broadcasting) broadcast waves, and terrestrial digital television (DTV) broadcast waves, are placed on the window glass installed in the opening of a vehicle.

Among these broadcast waves, terrestrial digital television broadcast waves have a relatively wide bandwidth of approximately 470 MHz to 710 MHz, and vehicle window glass equipped with antennas that can achieve the desired antenna sensitivity in this band is currently being developed.

For example, the following Patent Documents 1 to 4 disclose vehicle window glass equipped with a dipole antenna capable of receiving terrestrial digital television broadcast waves.

Japanese Patent Application Laid-Open No. 2010-206361 Japanese Patent Application Laid-Open No. 2010-273310 Japanese Patent Application Laid-Open No. 2012-085153 Patent Publication No. 2021-002721

There is a need for a vehicle window glass that has an antenna pattern different from those disclosed in the above-mentioned Patent Documents 1 to 4, is capable of receiving UHF band radio waves, particularly terrestrial digital television broadcast waves, and is equipped with an antenna that can be placed in a space-saving manner within the vehicle's glass opening.

In consideration of the above, the present invention aims to provide a vehicle window glass that can receive UHF band radio waves, particularly terrestrial digital television broadcast waves, with the desired sensitivity and has an antenna pattern that does not obstruct the occupant's field of vision.

A vehicle window glass according to the present invention comprises a glass plate attached to a vehicle body and an antenna provided on the glass plate, wherein the antenna has a first electrode and a power supply element connected to the first electrode, and a second electrode and a ground element connected to the second electrode, wherein the power supply element has an L-shaped element including a first element extending in a first direction from the first electrode and a second element extending in a second direction from an end of the first element opposite the first electrode, wherein the ground element has a first U-shaped element including a third element extending in the first direction from the second electrode, a fourth element extending in the second direction from an end of the third element opposite the second electrode, and a fifth element extending in a third direction from an end of the fourth element opposite the third element, wherein the second element is arranged on the side of the fourth element in the first direction .
Another aspect of the present invention provides a vehicle window glass comprising: a glass sheet to be attached to a vehicle body; and an antenna provided on the glass sheet, wherein the antenna has a first electrode, a feeding element connected to the first electrode, and a second electrode, a ground element connected to the second electrode, the feeding element having an L-shaped element including a first element extending from the first electrode in a first direction and a second element extending in a second direction from an end of the first element opposite to the first electrode, and the ground element has a third element extending from the second electrode in the first direction. a fourth element extending in the second direction from the end of the third element opposite the second electrode, and a fifth element extending in the third direction from the end of the fourth element opposite the third element, and when a partition line dividing the gap between the first electrode and the second electrode and extending along the first direction is used as a boundary to provide a first region in which the first electrode is arranged and a second region in which the second electrode is arranged, the second element intersects the partition line and extends from the first region toward the second region .
A vehicle window glass according to still another aspect of the present invention includes a glass sheet attached to a vehicle body and an antenna provided on the glass sheet, wherein the antenna has a first electrode and a power supply element connected to the first electrode, and a second electrode and a ground element connected to the second electrode, wherein the power supply element has an L-shaped element including a first element extending in a first direction from the first electrode and a second element extending in a second direction from an end of the first element opposite the first electrode, wherein the ground element has a first U-shaped element including a third element extending in the first direction from the second electrode, a fourth element extending in the second direction from an end of the third element opposite the second electrode, and a fifth element extending in a third direction from an end of the fourth element opposite the third element, and wherein the power supply element includes a seventh element electrically connected to the first electrode and extending in the fourth direction.

The vehicle window glass of the present invention can receive UHF band radio waves, particularly terrestrial digital television broadcast waves, with the desired sensitivity and has an antenna pattern that does not obstruct the occupant's field of vision.

1 is a front view of a vehicle window glass according to a first embodiment of the present invention; 1 is a front view of an antenna on a vehicle window glass according to a first embodiment of the present invention; FIG. 10 is a front view of an antenna for a vehicle window glass according to a second embodiment of the present invention. FIG. 10 is a front view of an antenna for a vehicle window glass according to a third embodiment of the present invention. FIG. 4 is a diagram showing measurement results of the antenna gain of the antenna according to the first embodiment. FIG. 10 is a diagram showing measurement results of the antenna gain of the antenna according to the second embodiment. FIG. 11 is a diagram showing measurement results of the antenna gain of the antenna according to the third embodiment.

First Embodiment
A vehicle window glass 20 according to a first embodiment of the present invention will be described below with reference to the accompanying drawings. The vehicle window glass 20 according to the first embodiment is installed in a vehicle 10. The X-axis shown in each drawing is parallel to the width direction of the vehicle 10 when the vehicle window glass 20 is installed, and the Y-axis is parallel to the vertical direction of the vehicle window glass 20 when the vehicle window glass 20 is installed. Furthermore, downward may be referred to as the "first direction," leftward may be referred to as the "second direction," upward may be referred to as the "third direction," and rightward may be referred to as the "fourth direction." In FIGS. 2 to 4, UP represents upward, and LH represents leftward. Furthermore, in this specification, "front view" refers to viewing an object along the Y-axis direction.

Figure 1 shows an example of the configuration of a vehicle window glass 20 according to a first embodiment of the present invention. The vehicle window glass 20 is provided on the body 12 of a vehicle 10, for example, as a vehicle windshield. However, the vehicle window glass 20 can also be used as a rear window or side window for a vehicle.

As shown in FIG. 1, the vehicle window glass 20 includes a glass plate 21 and an antenna 30. A camera module mounting portion 24 may also be formed in the center of the upper end of the glass plate 21 in the vehicle width direction.

As shown in FIG. 1, an opening 14 is formed in (the front part of) the vehicle body 12. The opening 14 is a space surrounded by a flange (metal part) provided on the vehicle body 12. For example, a glass plate 21, which is a component of the vehicle window glass 20, is fitted into the opening 14, and the peripheral edge of the glass plate 21 is fixed to the peripheral edge of the opening 14 with an adhesive such as urethane resin. The glass plate 21 is a transparent or translucent plate-shaped dielectric.

The camera module mounting portion 24 is an area for installing a camera module (not shown), and can be equipped with various electronic devices, including not only visible light cameras and infrared cameras, but also rain sensors. The camera module mounting portion 24 can be positioned arbitrarily. In other words, the vehicle window glass 20 does not need to include the camera module mounting portion 24. If the vehicle window glass 20 includes the camera module mounting portion 24, the antenna 30 may be affected by noise generated by the camera module, etc., so the distance from the elements constituting the antenna 30 to the camera module mounting portion 24 should be set to, for example, 50 mm or more. The distance from the elements constituting the antenna 30 to the camera module is preferably 70 mm or more, and more preferably 100 mm or more.

The dashed line in Figure 1 indicates the inner edge of the light-shielding film provided on one of the main surfaces of the glass plate 21. The light-shielding film may be, for example, an opaque colored ceramic layer. The color may be any, but dark colors such as black, brown, gray, or navy blue, or white are preferred, with a black ceramic layer being more preferred.

The antenna 30 is a so-called dipole antenna equipped with two electrodes. The antenna 30 receives radio waves in the frequency band (approximately 470-710 MHz, center frequency 590 MHz) of terrestrial digital television broadcast waves (hereinafter referred to as "DTV broadcast waves"). Furthermore, the glass plate 21 may be equipped with a combination of the same or different antennas 30 from the various embodiments described below, arranged in two or more locations. For example, if the glass plate 21 is equipped with two or more antennas 30 (for receiving DTV broadcast waves), these antennas form a diversity antenna. Furthermore, if the glass plate 21 has two (two-channel) antennas 30 arranged as a diversity antenna, the antennas may be arranged in two (left and right) regions separated by the central axis in the vertical direction of the glass plate 21, or may be arranged symmetrically (line-symmetrically) with respect to the central axis. Furthermore, in addition to the antenna 30, the glass plate 21 may be provided with an antenna that receives at least one frequency band other than that received by the antenna 30, such as AM broadcast waves, FM broadcast waves, or DAB (Band III) broadcast waves.

Figure 2 is a front view of the antenna 30 of the vehicle window glass 20 according to the first embodiment of the present invention. The antenna 30 is mounted on the glass plate 21 and has a power supply electrode (first electrode) 31, an earth electrode (second electrode) 40, a power supply element 32, and a ground element 41. The power supply element 32 and the ground element 41 are conductors formed to be suitable for receiving radio waves at DTV broadcast frequency.

The power supply electrode 31 and the earth electrode 40 are arranged side by side on the glass plate 21 in a direction parallel or approximately parallel to the X-axis direction (second direction), but they may also be arranged diagonally relative to the X-axis direction. Furthermore, in a front view of the vehicle window glass 20, the roof's front edge 12F (see FIG. 1), which extends in a direction approximately parallel to the second direction (X-axis direction) and is the end of a metal part corresponding to a flange, is located on the third direction side of the power supply electrode 31 and the earth electrode 40. The roof's front edge 12F corresponds to the boundary between the metal part and the glass plate 21. The power supply element 32 is connected to the power supply electrode 31, and the earth element 41 is connected to the earth electrode 40.

The power supply electrode 31 and the earth electrode 40 may each have an approximately rectangular electrode shape, but are not limited to this shape and may also be polygonal or circular. Note that an approximately rectangular shape also includes a rectangular shape with rounded corners, i.e., a shape that can be roughly considered a rectangle despite having rounded corners. In the antenna 30, for example, the inner conductor of a coaxial cable (not shown) as an example of a transmission line extending from a signal processing device (not shown) is electrically connected to the power supply electrode 31, and the outer conductor of the coaxial cable is electrically connected to the earth electrode 40. Note that the earth electrode 40 is also referred to as an earth portion connected to ground.

In the antenna 30, the feed element 32 includes an L-shaped element 33, which is made up of a first element 34 and a second element 35 and has a generally L-shape overall.

The first element 34 extends in the first direction from the power supply electrode 31 and is connected, for example, to a lower corner of the power supply electrode 31. However, as long as the power supply element 32 is electrically connected to the power supply electrode 31, the connection position is not particularly limited. In this specification, the term "the elements constituting the antenna extend along the Y axis (first direction, third direction)" means that the elements extend in a direction parallel to the Y axis when viewed from the front, and that the elements extend in a direction approximately parallel to the Y axis. "The elements are approximately parallel to the Y axis" means that the angle between the elements and the Y axis is greater than 0° and may be 30° or less, 20° or less, 10° or less, or 5° or less.

For example, even if the antenna 30 is provided in the upper end region (on the third direction side) of the glass plate 21, if the first element 34 extends in the first direction from the power supply electrode 31, the distance from the edge of the flange provided on the roof of the vehicle body 12 to the power supply element 32 can be set to a predetermined distance or greater (e.g., 30 mm or greater). This prevents a decrease in the antenna gain of the antenna 30 due to the power supply element 32 approaching the edge of the flange.

In the antenna 30, the second element 35 is an element that extends in the second direction from the first element 34 and is connected, for example, near the lower end of the first element 34, i.e., near the other end of the first element 34 that is different from the end on the power supply electrode 31 side. In this specification, the term "the elements constituting the antenna extend along the X-axis (second direction, fourth direction)" means that the elements extend in a direction parallel to the X-axis and in a direction approximately parallel to the X-axis. "The elements are approximately parallel to the X-axis" means that the angle between the elements and the X-axis is greater than 0° and may be 30° or less, 20° or less, 10° or less, or 5° or less.

In this embodiment, the first element 34 is approximately perpendicular to the second element 35. Note that the angle between the first element 34 and the second element 35 is not limited to 90°, and may be, for example, in the range of 60° to 120°, 70° to 110°, 80° to 100°, or 85° to 95°. The same applies to the angles between other elements that are connected to each other, as described below.

Next, the total length of the L-shaped element 33 in this embodiment is defined as DL. In other words, DL is the total length of the first element 34 and the second element 35. When the wavelength of the center frequency in air of the frequency band received by the antenna 30 is λ ₀ and the wavelength shortening rate of the glass plate 21 is k, the element length DL of the L-shaped element 33 should satisfy the following formula (1), and more preferably the following formula (2):

8/64 × λ ₀ × k ≦ DL ≦ 18/64 × λ ₀ × k...Formula (1)

9/64 × λ ₀ × k ≦ DL ≦ 16/64 × λ ₀ × k...Formula (2)

If DL is within the range of equation (1), the L-shaped element 33 resonates in the frequency band of the DTV broadcast waves, thereby improving the antenna gain of the antenna 30, and if DL is within the range of equation (2), the antenna gain is further improved.

Furthermore, by making the L-shaped element 33 of the antenna 30 horizontally elongated, with its horizontal length longer than its vertical length, it can be positioned along the end 12F of the flange provided on the roof of the vehicle body 12, making it less likely to obstruct the occupant's field of vision.

Furthermore, in the antenna 30, the ground element 41 has a third element 43, a fourth element 44, a fifth element 45, and a sixth element 46.

The third element 43 is an element that extends in the first direction from the earth electrode 40 and is connected, for example, to a lower corner of the earth electrode 40. However, as long as the ground element 41 is electrically connected to the earth electrode 40, the connection position is not particularly limited.

The fourth element 44 is an element that extends in the second direction from the third element 43 and is connected, for example, near the lower end of the third element 43, i.e., near the other end of the third element 43 that is different from the end on the earth electrode 40 side.

The fifth element 45 is an element that extends from the fourth element 44 in the third direction and is connected to the vicinity of the other end of the fourth element 44 that is different from the end on the third element 43 side.

The third element 43, fourth element 44, and fifth element 45 form a generally U-shape as a whole. Therefore, the section consisting of the third element 43, fourth element 44, and fifth element 45 is referred to as the first U-shaped element 42.

The sixth element 46 is an element that extends in the fourth direction from the fifth element 45 and can be added as desired. This also applies to the second and third embodiments described below. The sixth element 46 is connected, for example, to the vicinity of the other end of the fifth element 45 that is different from the end on the fourth element 44 side, and has an open end. Furthermore, the ground element 41 including the first U-shaped element 42 and the sixth element 46 is also referred to as a loop-shaped element 47.

Next, the overall length of the ground element 41 in this embodiment is defined as DG. In other words, DG is the total length of the third element 43, the fourth element 44, the fifth element 45, and the sixth element 46. The element length DG of the ground element 41 preferably satisfies the following formula (3), and more preferably satisfies the following formula (4). Note that if the sixth element 46 is not included, the element length DG of the ground element 41 corresponds to the total length of the third element 43, the fourth element 44, and the fifth element 45, that is, the length of the first U-shaped element 42.

12/64 × λ ₀ × k ≦ DG ≦ 24/64 × λ ₀ × k...Formula (3)

14/64 × λ ₀ × k ≦ DG ≦ 22/64 × λ ₀ × k...Formula (4)

If DG is within the range of equation (3), the ground element 41 resonates in the frequency band of the DTV broadcast waves, improving the antenna gain of the antenna 30, and if it is within the range of equation (4), the antenna gain is further improved.

When viewing the glass plate 21 from the front, the straight line that bisects the gap between the power supply electrode 31 and the earth electrode 40 and extends along the Y axis is defined as the partition line LD. Furthermore, the region of the glass plate 21 to the right of the partition line LD is referred to as the first region AR1, and the region to the left of the partition line LD is referred to as the second region AR2. In this case, the second element 35 intersects the partition line LD and extends from the first region AR1 toward the second region AR2.

The dimension LL1 (see Figure 2) of the entire antenna 30 in the X-axis direction is preferably 150 mm or less, more preferably 120 mm or less, and even more preferably 100 mm or less. Here, the dimension LL1 in the X-axis direction refers to the dimension in the X-axis direction between the right edge of the power supply electrode 31 and the fifth element 45. If the dimension LL1 is set to 150 mm or less, the entire antenna 30 will be compact.

Furthermore, when the glass plate 21 is viewed from the front, an imaginary straight line IL may be formed along the Y-axis that intersects with the second element 35 and the fourth element 44. In other words, the second element 35 and the fourth element 44 are arranged side by side in the vertical direction, and when the above-mentioned imaginary straight line IL extending in the vertical direction is given, the second element 35 and the fourth element 44 may intersect with the imaginary straight line IL. Furthermore, if the ground element 41 includes the sixth element 46, an imaginary straight line IL may be formed that intersects only the second element 35 and the fourth element 44, but does not intersect with the sixth element 46. In this case, the second element 35 is located closer to the first direction than the fourth element 44, i.e., farther from the flange end 12F than the fourth element 44.

Second Embodiment
Next, a vehicle window glass 50 according to a second embodiment of the present invention will be described with reference to Fig. 3. Note that the same components as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The vehicle window glass 50 of the second embodiment includes a glass plate 21 and an antenna 55. The antenna 55 has the same structure as the antenna 30 except for the inclusion of a seventh element 57. That is, the power supply element 32 of the antenna 55 includes the seventh element 57 in addition to the L-shaped element 33.

The seventh element 57 is an element that extends from the power supply electrode 31 in the fourth direction and is connected, for example, to a lower corner of the power supply electrode 31. However, as long as the seventh element 57 is electrically connected to the power supply electrode 31, the connection position is not particularly limited. In addition, in this embodiment, the seventh element 57 extends from the power supply electrode 31 in the fourth direction and has an open end.

In this embodiment, the overall length of the seventh element 57 is defined as D7. The element length D7 of the seventh element 57 preferably satisfies the following formula (5), and more preferably satisfies the following formula (6).

7/64 × λ ₀ × k ≦ D7 ≦ 13/64 × λ ₀ × k...Formula (5)

8/64 × λ ₀ × k≦ D7 ≦ 12/64 × λ ₀ × k...Formula (6)

If D7 is within the range of equation (5), the seventh element 57 resonates in the frequency band of the DTV broadcast waves, improving the antenna gain of the antenna 55, and if it is within the range of equation (6), the antenna gain is further improved.

The dimension LL2 (see Figure 3) of the entire antenna 55 in the X-axis direction is preferably 150 mm or less. Here, the dimension LL2 in the X-axis direction refers to the dimension in the X-axis direction between the right edge of the seventh element 57 and the fifth element 45. If the dimension LL2 is 150 mm or less, the entire antenna 55 will be compact, which is preferable.

In this way, the power supply element 32 of the antenna 55 has a seventh element 57 that extends from the power supply electrode 31 toward the opposite side of the ground element 41. As a result, the power supply element 32 and the ground element 41 are oriented in opposite directions, maximizing the current distribution between the power supply electrode 31 and the earth electrode 40, thereby improving the antenna gain of the antenna 55 in the specified frequency band.

Third Embodiment
Next, a vehicle window glass 60 according to a third embodiment of the present invention will be described with reference to Fig. 4. Note that the same components as those in the second embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The vehicle window glass 60 of the third embodiment includes a glass plate 21 and an antenna 65. The antenna 65 has the same structure as the antenna 55, except that it includes an eighth element 67 and a ninth element 68.

The eighth element 67 is an element extending from the seventh element 57 in the first direction and is connected, for example, near the other end of the seventh element 57 that is different from the end on the power supply electrode 31 side. The ninth element 68 is an element extending from the eighth element 67 in the second direction and is connected, for example, near the lower end of the eighth element 67, i.e., near the other end of the eighth element 67 that is different from the end on the seventh element 57 side, and has an open end.

The seventh element 57, the eighth element 67, and the ninth element 68 form a generally U-shape as a whole. Therefore, the section consisting of the seventh element 57, the eighth element 67, and the ninth element 68 is referred to as the second U-shaped element 69.

In this embodiment, the total length of the second U-shaped element 69 is defined as DU2. In other words, DU2 is the total length of the seventh element 57, the eighth element 67, and the ninth element 68. The total length DU2 of the second U-shaped element 69 preferably satisfies the following formula (7), and more preferably satisfies formula (8):

17/64 × λ ₀ × k ≦ DU2 ≦ 32/64 × λ ₀ × k...Formula (7)

20/64 × λ ₀ × k ≦ DU2 ≦ 30/64 × λ ₀ × k...Formula (8)

If DU2 is within the range of equation (7), the second U-shaped element 69 resonates in the frequency band of the DTV broadcast waves, thereby improving the antenna gain of the antenna 65, and if it is within the range of equation (8), the antenna gain is further improved.

The dimension LL3 (see Figure 4) of the entire antenna 65 in the X-axis direction is preferably 150 mm or less. Here, the dimension LL3 in the X-axis direction refers to the dimension in the X-axis direction between the right edge of the seventh element 57 (eighth element 67) and the fifth element 45. If the dimension LL3 is 150 mm or less, the entire antenna 65 will be compact, which is preferable.

Furthermore, because the second U-shaped element 69 has a folded shape, the antenna 65 not only achieves space savings but also aligns the direction of current distribution. In this way, by including the second U-shaped element 69 in the antenna 65, the currents in the second U-shaped element 69 are in phase, thereby achieving increased antenna gain for the antenna 65. Furthermore, by making the second U-shaped element 69 horizontally longer than its vertical length, it can be positioned along the end 12F of the flange provided on the roof of the vehicle body 12, making it less likely to obstruct the occupant's field of view.

In the antennas 30, 55, and 65 of the vehicle window glasses 20, 50, and 60 according to the first to third embodiments, the power supply element 32 may be provided above, rather than below, the power supply electrode 31. In this case, the ground element 41 may be provided above, rather than below, the earth electrode 40.

Next, we will explain the measurement results of the antenna gain in the DTV broadcast wave band for antennas 30, 55, and 65 mounted on a glass plate 21 fixed as a windshield to an actual vehicle, with reference to Figures 5 to 7.

<Example 1>
5A to 5C are diagrams showing measurement results of the antenna gain of the antenna 30 according to the first embodiment. In Fig. 5 to Fig. 7, the vertical axis represents the antenna gain (unit: dBd), and the horizontal axis represents the frequency (unit: MHz).

In Example 1, the dimensions of each part of the antenna 30 in Figure 2 were set as follows. All of the following dimensions satisfy the conditional expressions (1) to (4) described in the first embodiment. The wavelength shortening rate k of the glass plate is approximately 0.64.
D1 (first element 34): 15 mm
D2 (second element 35): 55 mm
DL (L-shaped element 33): 70 mm
D3 (third element 43): 10 mm
D4 (fourth element 44): 50 mm
D5 (fifth element 45): 10 mm
D6 (sixth element 46): 20 mm
DG (ground element 41): 90 mm
Gap between the power supply electrode 31 and the earth electrode 40: 10 mm
Overall dimension LL1 of the antenna 30 in the X-axis direction: 80 mm

As is clear from the measurement results in Figure 5, the antenna 30 on the vehicle window glass 20 is able to receive DTV broadcast waves at a sufficient level.

<Example 2>
FIG. 6 is a diagram showing the measurement results of the antenna gain of the antenna 55 according to the second embodiment.

In Example 2, the dimensions of each part of the antenna 55 in Fig. 3 were set as follows: All of the following dimensions satisfy the conditional expressions (5) and (6) described in the second embodiment.
D1 (first element 34): 15 mm
D2 (second element 35): 55 mm
DL (L-shaped element 33): 70 mm
D3 (third element 43): 10 mm
D4 (fourth element 44): 50 mm
D5 (fifth element 45): 10 mm
D6 (sixth element 46): 20 mm
DG (ground element 41): 90 mm
D7 (7th element 57): 50 mm
Gap between the power supply electrode 31 and the earth electrode 40: 10 mm
Overall dimension LL2 of the antenna 55 in the X-axis direction: 130 mm

As is clear from the measurement results in Figure 6, the antenna 55 on the vehicle window glass 50 is able to receive DTV broadcast waves at a sufficient level.

<Example 3>
FIG. 7 is a diagram showing the measurement results of the antenna gain of the antenna 65 according to the third embodiment.

In Example 3, the dimensions of each part of the antenna 65 in Fig. 4 were set as follows: All of the following dimensions satisfy the conditional expressions (7) and (8) described in the third embodiment.
D1 (first element 34): 15 mm
D2 (second element 35): 55 mm
DL (L-shaped element 33): 70 mm
D3 (third element 43): 10 mm
D4 (fourth element 44): 50 mm
D5 (fifth element 45): 10 mm
D6 (sixth element 46): 20 mm
DG (ground element 41): 90 mm
D7 (7th element 57): 50 mm
D8 (8th element 67): 15 mm
D9 (9th element 68): 60 mm
DU2 (second U-shaped element 69): 125 mm
Gap between the power supply electrode 31 and the earth electrode 40: 10 mm
Overall dimension LL3 of the antenna 65 in the X-axis direction: 130 mm

As is clear from the measurement results in Figure 7, the antenna 65 on the vehicle window glass 60 is able to receive DTV broadcast waves at a sufficient level.

The configurations of the first to third embodiments described above are merely examples of the content of the present invention, and may be combined with other known technologies, or portions of the configuration may be omitted or modified without departing from the spirit of the present invention.

Furthermore, the open end of each element is located at the tip in the extension direction, but the area near the tip may have a portion that is bent in a direction different from the extension direction. Furthermore, the area near the tip on the opposite side of the open end of each element may also have a portion that is bent in a direction different from the extension direction. In this way, the shape of the elements that make up each antenna may differ partially from the antenna shape shown in each embodiment, as long as it does not deviate from the reception sensitivity.

12 Vehicle body 20 Vehicle window glass 21 Glass plate 30 Antenna 31 Power supply electrode (first electrode)
32: Power supply element 33: L-shaped element 34: First element 35: Second element 40: Earth electrode (second electrode)
41 Ground element 42 First U-shaped element 43 Third element 44 Fourth element 45 Fifth element 46 Sixth element 47 Loop element 50 Vehicle window glass 55 Antenna 57 Seventh element 60 Vehicle window glass 65 Antenna 67 Eighth element 68 Ninth element 69 Second U-shaped element LD Partition line AR1 First region AR2 Second region IL Virtual straight line

Claims (15)

a glass plate attached to the vehicle body;
an antenna provided on the glass plate;
Equipped with
The antenna is
a first electrode and a power supply element connected to the first electrode;
a second electrode and a ground element connected to the second electrode;
and
the power supply element has an L-shaped element including a first element extending in a first direction from the first electrode and a second element extending in a second direction from an end of the first element opposite to the first electrode,
the ground element has a first U-shaped element including: a third element extending in the first direction from the second electrode; a fourth element extending in the second direction from an end of the third element opposite the second electrode; and a fifth element extending in a third direction from an end of the fourth element opposite the third element ;
The second element is disposed on the first direction side of the fourth element . a glass plate attached to the vehicle body;
an antenna provided on the glass plate;
Equipped with
The antenna is
a first electrode and a power supply element connected to the first electrode;
a second electrode and a ground element connected to the second electrode;
and
the power supply element has an L-shaped element including a first element extending in a first direction from the first electrode and a second element extending in a second direction from an end of the first element opposite to the first electrode,
the ground element has a first U-shaped element including: a third element extending in the first direction from the second electrode; a fourth element extending in the second direction from an end of the third element opposite the second electrode; and a fifth element extending in a third direction from an end of the fourth element opposite the third element ;
When a first region is defined as a region in which the first electrode is disposed and a second region is defined as a region in which the second electrode is disposed, with a partition line that divides the gap between the first electrode and the second electrode in half and that extends along the first direction as a boundary,
The second element intersects the partition line and extends from the first region toward the second region . a glass plate attached to the vehicle body;
an antenna provided on the glass plate;
Equipped with
The antenna is
a first electrode and a power supply element connected to the first electrode;
a second electrode and a ground element connected to the second electrode;
and
the power supply element has an L-shaped element including a first element extending in a first direction from the first electrode and a second element extending in a second direction from an end of the first element opposite to the first electrode,
the ground element has a first U-shaped element including: a third element extending in the first direction from the second electrode; a fourth element extending in the second direction from an end of the third element opposite the second electrode; and a fifth element extending in a third direction from an end of the fourth element opposite the third element ;
The vehicle window glass, wherein the power supply element includes a seventh element electrically connected to the first electrode and extending in a fourth direction. The vehicle window glass according to claim 1, wherein the grounding element has a loop-shaped element including a sixth element extending in the fourth direction from the end of the fifth element opposite the fourth element. The vehicle window glass according to claim 2 , wherein an imaginary line extending along the first direction intersects with the second element and the fourth element. The element length DG of the ground element is expressed as follows, where λ ₀ is the wavelength of the center frequency in the air in the frequency band received by the antenna, and k is the wavelength shortening rate of the glass plate:
12/64 × λ ₀ × k ≦ DG ≦ 24/64 × λ ₀ × k
The vehicle window glass according to any one of claims 1 to 5, which satisfies the following: The element length DL of the L-shaped element is given by the following equation, where λ ₀ is the wavelength of the center frequency in the air in the frequency band received by the antenna, and k is the wavelength shortening rate of the glass plate:
8/64 × λ ₀ × k ≦ DL ≦ 18/64 × λ ₀ × k
The vehicle window glass according to any one of claims 1 to 6, which satisfies the following: 4. The vehicle window glass according to claim 3, wherein the power supply element has a second U-shaped element including the seventh element, an eighth element extending in the first direction from an end of the seventh element opposite to the first electrode, and a ninth element extending in the second direction from an end of the eighth element opposite to the seventh element . The seventh element of the feeding element has an open end at its tip end,
The element length D7 of the seventh element is given by: where λ ₀ is the wavelength of the center frequency in the air in the frequency band received by the antenna, and k is the wavelength shortening rate of the glass plate.
7/64 × λ ₀ × k ≦ D7 ≦ 13/64 × λ ₀ × k
4. The vehicle window glass according to claim 3 , which satisfies the following: The element length DU2 of the second U-shaped element is expressed as follows, where λ ₀ is the wavelength of the center frequency in the air in the frequency band received by the antenna, and k is the wavelength shortening rate of the glass plate:
17/64 × λ ₀ × k ≦ DU2 ≦ 32/64 × λ ₀ × k
9. The vehicle window glass according to claim 8 , which satisfies the following: The vehicle window glass according to claim 1 , wherein the first electrode and the second electrode are arranged parallel or substantially parallel to the second direction. 12. The vehicle window glass according to claim 11 , wherein the width of the antenna in the parallel direction is 150 mm or less. 13. The vehicle window glass according to claim 11, wherein when the glass plate is attached to the vehicle body, a metal portion that is substantially parallel to the second direction is arranged on the third direction side of the first electrode and the second electrode. The vehicle window glass according to any one of claims 1 to 13 , wherein the antenna is capable of receiving radio waves in a frequency band for terrestrial digital television broadcast waves. 15. The vehicle window glass according to claim 1 , wherein the glass sheet comprises at least one of a windshield, a side glass, and a rear glass.