JP7794068B2 - Vehicle window glass - Google Patents

Description

This disclosure relates to vehicle window glass.

Conventionally, there is known an automobile glass antenna that includes an antenna conductor for the FM broadcast band and an independent conductor that is capacitively coupled to the antenna conductor. In this glass antenna, a first antenna element included in the independent conductor is connected to each of multiple second antenna elements near the center of the window glass in the left-right direction, so as to extend longitudinally across the second antenna elements (see, for example, Patent Document 1). According to Patent Document 1, the first antenna element has the function of improving the antenna gain of vertically polarized waves in the high frequency band, and the second antenna element has the function of improving the antenna gain of horizontally polarized waves in the high frequency band.

WO 2008/153079

However, with conventional glass antennas, the first antenna element crosses multiple second antenna elements near the center of the window glass, which can reduce visibility through the window glass.

This disclosure provides a vehicle window glass that is equipped with an antenna that receives radio waves in a specified frequency band, improving visibility.

According to one aspect of the present disclosure,
A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
the antenna includes a power supply portion, an antenna element electrically connected to the power supply portion, and a parasitic element provided on the glass plate;
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element connected to the vicinity of the first end and including a portion extending in a second direction different from the first direction or a third direction opposite to the second direction,
The first element has an intermediate section of 85% of the length from the first end to the second end, to which no other conductor is connected;
The vehicle window glass is provided, wherein the antenna element is located on the opposite side of the second end with respect to the second element and includes a portion that is capacitively coupled with the second element.

One aspect of the present disclosure provides a vehicle window glass that is equipped with an antenna that receives radio waves in a specified frequency band, improving visibility.

FIG. 2 is a diagram illustrating an example of a window glass according to the first embodiment. FIG. 10 is a diagram illustrating an example of a window glass according to a second embodiment. FIG. 10 is a diagram showing an example of a window glass according to a third embodiment. FIG. 10 is a diagram showing an example of a window glass according to a fourth embodiment. FIG. 10 is a diagram showing an example of a window glass according to a fifth embodiment. FIG. 13 is a diagram showing an example of a window glass according to a sixth embodiment. FIG. 13 is a diagram showing an example of a window glass according to a seventh embodiment. FIG. 13 is a diagram showing an example of a window glass according to an eighth embodiment. FIG. 13 is a diagram showing an example of a window glass according to a ninth embodiment. FIG. 23 is a diagram showing an example of a window glass according to a tenth embodiment. FIG. 23 is a diagram showing an example of a window glass according to an eleventh embodiment. 10A and 10B are diagrams illustrating an example of the configuration of an antenna provided on a glass plate. FIG. 10 is a diagram showing an example of a simulation result of antenna gain for vertically polarized waves in the FM broadcast wave band when the power supply unit is arranged close to the side edge of the glass plate. FIG. 10 is a diagram showing an example of a simulation result of antenna gain for vertically polarized waves in the FM broadcast wave band when the power supply unit is disposed close to the bottom side of the glass plate. FIG. 10 is a diagram showing an example of a simulation result of antenna gain for vertically polarized waves in the DAB Band III band when a power feed unit is arranged close to a side edge of a glass plate. FIG. 2 is a diagram showing an example of the results of a simulation of the change in the average value of the antenna gain of vertically polarized waves in the FM broadcast wave band with respect to the change in L _C /L _H in the configuration of FIG. 1 , when the maximum average value is set to 0 dB. FIG. 2 is a diagram showing an example of the results of a simulation of the change in the average antenna gain of vertically polarized waves in the FM broadcast wave band with respect to the change in the lateral position of the first element in the configuration of FIG. 1, when the maximum average value of the antenna gain is set to 0 dB. FIG. 10 is a diagram showing an example of the results of a simulation of the change in the average value of the antenna gain of vertically polarized waves in the FM broadcast wave band with respect to the change in the lateral position of the first element in the configuration of FIG. 9, when the maximum average value of the antenna gain is set to 0 dB. FIG. 10 is a diagram showing an example of the results of a simulation of the change in the average value of the antenna gain of vertically polarized waves in the FM broadcast wave band with respect to the change in d/(k×λ) in the configuration of FIG. 9, when the maximum average value is set to 0 dB.

Embodiments will be described below 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. Directions such as parallel, right angle, orthogonal, horizontal, vertical, up and down, left and right, as well as terms such as identical and equal, are permissible to the extent that they do not impair the functions and effects of the embodiments.

Examples of vehicle window glass to which this embodiment can be applied include rear glass attached to the rear of a vehicle, windshields attached to the front of a vehicle, side glass attached to the sides of a vehicle, and roof glass attached to the roof of a vehicle. Vehicle window glass is not limited to these examples, and may also be, for example, a window glass in which the roof glass is integrated with either or both of the windshield and rear glass.

In the following description, the first direction D1, second direction D2, third direction D3, and fourth direction D4 represent the directions when the main surface of the window glass is viewed from inside the vehicle. The fourth direction D4 is the opposite direction to the first direction D1, and the third direction D3 is the opposite direction to the second direction D2. As long as the action and effect of the embodiment are not impaired, the angle between the first direction D1 and the second direction D2 may be an angle of 45° or more and 135° or less, an angle of 60° or more and 120° or less, an angle of 75° or more and 105° or less, or an angle of 90°. As long as the functions and effects of the embodiment are not impaired, the angle between the second direction D2 and the third direction D3, or the angle between the first direction D1 and the fourth direction D4 may be an angle between 135° and 180°, an angle between 150° and 180°, an angle between 165° and 180°, or an angle of 180°. Of the first direction D1, the second direction D2, the third direction D3, and the fourth direction D4, any two adjacent directions may be approximately perpendicular to each other.

Figure 1 is a diagram showing an example of the configuration of a vehicle window glass according to the first embodiment. Figure 1 shows a window glass 201 attached to a metal body 41 of a vehicle as seen from inside the vehicle. The window glass 201 is an example of a vehicle window glass. Figure 1 shows an example of a window glass 201 used as a side window of a vehicle. The window glass 201 includes a glass plate 43 for the side window and an antenna 70 that receives radio waves in a predetermined frequency band W.

The glass plate 43 is attached to a metal body 41, which is an example of a metal part of a vehicle. The metal body 41 is, for example, a window frame (flange) to which the glass plate 43 is attached using an adhesive or the like. The glass plate 43 is attached to the metal body 41 so as to cover an opening 42 formed in the metal body 41. The metal body 41 has four edges 42a, 42b, 42c, and 42d that form the opening 42.

The antenna 70 has a power supply section 72, an antenna element 71, and a parasitic element 60.

The power supply portion 72 is a power supply terminal for supplying power to the antenna element 71. The power supply portion 72 is, for example, an electrode formed on the main surface of the glass plate 43. The shape of the power supply portion 72 is not limited to rectangular and may be other shapes such as circular. The power supply portion 72 is electrically connected to a conductive member 20 (Figure 12) that supplies power to the antenna element 71. Figure 12 will be described later.

In FIG. 1, one end of the conductive member 20 is electrically connected to the power supply unit 72, and the other end of the conductive member 20 is electrically connected to a receiver (not shown) mounted on the vehicle. A received signal (high-frequency current) corresponding to radio waves received by the antenna 70 flows through the conductive member 20. The conductive member 20 is a member including, for example, an electric wire (wire harness), a wiring pattern, a spring, or a transmission line. Specific examples of electric wires include wiring such as AV lines and AVSS lines. Specific examples of transmission lines include coaxial cables, microstrip lines, strip lines, coplanar lines, and slot lines.

An amplifier (not shown) may be connected between the power supply unit 72 and the conductive member 20. The amplifier amplifies a signal corresponding to the radio waves received by the antenna 70 and outputs it to the conductive member 20.

The antenna element 71 is a conductor electrically connected to the power supply 72. While FIG. 1 illustrates a straight antenna element 71, the antenna element 71 may include a curved portion. The antenna element 71 extends along the end edge 42d to the open end 73. The antenna element 71 extends along the end edge 42d and includes a portion that is capacitively coupled to the end edge 42d. By including a portion that is capacitively coupled to the end edge 42d, the antenna gain of the antenna 70 in the frequency band W is improved.

The parasitic element 60 is a linear conductor provided on the surface or inner layer of the glass plate 43. The parasitic element 60 is positioned away from the antenna element 71 and the power supply 72. The parasitic element 60 has a first element 61, a second element 62, and a third element 63. However, the parasitic element 60 may or may not include the third element 63.

The first element 61 extends in a straight line in the first direction D1 from the first end 81 to the second end 82 through the center of the glass plate 43. The second element 62 is connected to the vicinity of the first end 81 of the first element 61 and includes a portion extending in a second direction D2 different from the first direction D1. The vicinity of the first end 81 refers to the portion of the first element 61 that includes the first end 81. The third element 63 is connected to the vicinity of the second end 82 of the first element 61 and includes a portion extending in a third direction D3 opposite the second direction D2. The vicinity of the second end 82 refers to the portion of the first element 61 that includes the second end 82. The first element 61 is an element to which no other conductors are connected in an intermediate section 10 that corresponds to 85% of the length L from the first end 81 to the second end 82. The antenna element 71 is located on the opposite side of the second element 62 from the second end 82, and includes a portion that is capacitively coupled to the second element 62. Note that if the parasitic element 60 does not include the third element 63, the second end 82 will be an open end.

According to the first embodiment, the first element 61 has no other conductors connected to the intermediate section 10, which is 85% of the length L from the first end 81 to the second end 82. Therefore, even if the first element 61 extends through the center of the glass plate 43 in the first direction D1, the view through the glass plate 43 is unlikely to be obstructed.

The intermediate section 10 is the element portion of the first element 61 extending from the first section end 11 to the second section end 12. The first section end 11 may coincide with the first end 81, and the second section end 12 may coincide with the second end 82. Other conductors, such as branch elements, may be connected to sections of the first element 61 excluding the intermediate section 10; however, in terms of improving visibility through the glass plate 43, it is preferable that no other conductors be connected. In this example, the section of the first element 61 excluding the intermediate section 10 is the section from the first section end 11 to the first end 81, or the section from the second section end 12 to the second end 82. The length of the intermediate section 10 may be 85% of the length L; however, in terms of improving visibility through the glass plate 43, 90% of the length L is preferred, 95% of the length L is more preferred, and 100% of the length L is most preferred. The length of the intermediate section 10 being 100% of the length L means that the intermediate section 10 coincides with the first element 61. The description of the intermediate section 10 will be used in conjunction with other embodiments described below.

The first element 61 may be two parallel wires spaced apart from each other from the first end 81 to the second end 82, but a single wire extending from the first end 81 to the second end 82 is preferred in terms of improving visibility through the glass plate 43.

Furthermore, if the antenna element 71 has a portion that runs parallel to the parasitic element 60 in close proximity, the electric field near the parallel portion can be strengthened, thereby improving the antenna gain of the antenna 70. In the example shown in Figure 1, the parallel portion corresponds to the portion that runs parallel to the second element 62.

Therefore, according to the first embodiment, a window glass 201 with improved visibility can be provided, equipped with an antenna 70 that receives radio waves in a specified frequency band W.

Frequency band W may be, for example, the UHF (Ultra High Frequency) band with frequencies from 300 MHz to 3 GHz, the VHF (Very High Frequency) band with frequencies from 30 MHz to 300 MHz, or a band spanning both. Specific examples of frequency bands included in the UHF band include the band of terrestrial digital television broadcast waves (e.g., 470 MHz to 710 MHz). Specific examples of frequency bands included in the VHF band include the band of FM broadcast waves (e.g., 76 MHz to 108 MHz) and the DAB Band III band (e.g., 174 MHz to 240 MHz).

The length of the antenna element 71 is L _H , and the length of the portion of the parasitic element 60 that is capacitively coupled to the antenna element 71 is L _C. In this case, L _C /L _H satisfies the following equation: L _C /L _H ≧0.14 (Equation 1a)
When the above condition is satisfied, the antenna gain of the antenna 70 in the frequency band W is improved.

The antenna gain of the antenna 70 in the frequency band W is improved.
L _C /L _H ≧0.16...Formula 1b
is preferred,
L _C /L _H ≧0.18...Formula 1c
is more preferred.

The length of the antenna element 71 is L _H , the wavelength of the radio wave in the air at the center frequency of a predetermined frequency band W is λ, and the wavelength shortening rate due to the glass plate 43 is k. In this case, L _H is expressed as follows:
0.03×λ×k≦L _H ≦1.30×λ×k
...Formula 2a
When the above condition is satisfied, the antenna gain of the antenna 70 in the frequency band W is improved.

The antenna gain of the antenna 70 in the frequency band W is improved.
0.04×λ×k≦L _H ≦1.20×λ×k
...Formula 2b
is preferred,
0.05×λ×k≦L _H ≦1.10×λ×k
...Formula 2c
is more preferred.

The longest length connecting the two open ends 83 and 84 of the parasitic element 60 is denoted by L _P , the wavelength of radio waves in the air at the center frequency of a predetermined frequency band W is denoted by λ, the wavelength shortening rate due to the glass plate 43 is denoted by k, and an integer equal to or greater than 1 is denoted by n. In this case, L _P is expressed as follows:
0.70×(λ/2)×k×n≦L _P ≦1.30×(λ/2)×k×n
...Formula 3a
When the above expression (1) is satisfied, the antenna gain of the antenna 70 in the frequency band W is improved. In the example shown in FIG. 1 , L _P corresponds to the sum of the lengths of the first element 61, the second element 62, and the third element 63. If the parasitic element 60 does not include the third element 63, the second end 82 becomes an open end, and therefore L _P corresponds to the sum of the lengths of the first element 61 and the second element 62.

The antenna gain of the antenna 70 in the frequency band W is improved.
0.80×(λ/2)×k×n≦L _P ≦1.20×(λ/2)×k×n
...Formula 3b
is preferred,
0.90×(λ/2)×k×n≦L _P ≦1.10×(λ/2)×k×n
...Formula 3c
is more preferred.

The third element 63 is positioned so that it capacitively couples with the metal portion around the glass plate 43 (in this example, the edge 42a of the metal body 41) when the glass plate 43 is attached to the vehicle. This improves the antenna gain of the antenna 70 in frequency band W.

In the example shown in FIG. 1, when the glass plate 43 is attached to a vehicle, the first element 61 includes a portion that extends in a direction approximately perpendicular to the horizontal direction, and the second element 62 and the third element 63 include portions that extend in an approximately horizontal direction. As a result, the first element 61 has the effect of improving the antenna gain of vertically polarized waves in frequency band W, and the second element 62 and the third element 63 have the effect of improving the antenna gain of horizontally polarized waves in frequency band W.

In FIG. 1, when the glass plate 43 is attached to a vehicle, the metal portion around the glass plate 43 (in this example, the metal body 41) includes an edge 42c in the third direction D3 and an edge 42b in the second direction D2. Edge 42c is an example of a first edge. Edge 42b is an example of a second edge. Here, the center position between edge 42c and edge 42b is represented as 0, the position of edge 42c is represented as -1, and the position of edge 42b is represented as +1. In this case, if the first element 61 includes a portion located within the range of -0.3 to +0.8, the antenna gain of the antenna 70 in frequency band W is improved. In terms of improving the antenna gain of the antenna 70 in frequency band W, it is preferable that the entire first element 61 is located within the range of -0.3 to +0.8. If the position of the first element 61 deviates from this range, the first element 61 will approach the end edge 42c or end edge 42b, reducing the antenna gain of the antenna 70 in frequency band W.

Figure 2 is a diagram showing an example configuration of a vehicle window glass according to the second embodiment. In the second embodiment, the description of the configuration, actions, and effects similar to those of the first embodiment will be omitted or simplified by incorporating the above description. The window glass 202 shown in Figure 2 differs from the window glass 201 shown in Figure 1 in that the third element 63 includes a portion extending in the second direction D2.

In the second embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the second embodiment, a window glass 202 can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W and has improved visibility.

Figure 3 is a diagram showing an example configuration of a vehicle window glass according to the third embodiment. In the third embodiment, the description of the configuration, actions, and effects similar to those of the above embodiments will be omitted or simplified by incorporating the above description. The window glass 203 shown in Figure 3 differs from the window glass 201 shown in Figure 1 in the extension direction of each element.

In FIG. 3, the antenna element 71 extends along the end edge 42b to the open end 73. The antenna element 71 extends along the end edge 42b and includes a portion that is capacitively coupled to the end edge 42b. By including a portion that is capacitively coupled to the end edge 42b, the antenna element 71 improves the antenna gain of the antenna 70 in the frequency band W.

In Figure 3, the third element 63 is positioned so that it is capacitively coupled with the metal portion around the glass plate 43 (in this example, the edge 42c of the metal body 41) when the glass plate 43 is attached to the vehicle. This improves the antenna gain of the antenna 70 in frequency band W.

In the example shown in Figure 3, when the glass plate 43 is attached to a vehicle, the first element 61 includes a portion that extends in a substantially horizontal direction, and the second element 62 and the third element 63 include portions that extend in a direction substantially perpendicular to the horizontal direction. As a result, the first element 61 has the effect of improving the antenna gain for horizontally polarized waves in frequency band W, and the second element 62 and the third element 63 have the effect of improving the antenna gain for vertically polarized waves in frequency band W.

In Figure 3, when the glass plate 43 is attached to a vehicle, the metal portion around the glass plate 43 (in this example, the metal body 41) includes an edge 42d in the third direction D3 and an edge 42a in the second direction D2. Edge 42d is an example of a first edge. Edge 42a is an example of a second edge. Here, the center position between edge 42d and edge 42a is represented as 0, the position of edge 42d is represented as -1, and the position of edge 42a is represented as +1. In this case, if the first element 61 includes a portion located within the range of -0.3 to +0.8, the antenna gain of the antenna 70 in frequency band W is improved. In terms of improving the antenna gain of the antenna 70 in frequency band W, it is preferable that the entire first element 61 is located within the range of -0.3 to +0.8. If the position of the first element 61 deviates from this range, the first element 61 will approach the end edge 42d or end edge 42a, reducing the antenna gain of the antenna 70 in frequency band W.

In the third embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the third embodiment, a window glass 203 with improved visibility can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W.

Figure 4 is a diagram showing an example configuration of a vehicle window glass according to the fourth embodiment. In the fourth embodiment, the description of the configuration, actions, and effects similar to those of the above embodiments will be omitted or simplified by incorporating the above description. The window glass 204 shown in Figure 4 differs from the window glass 203 shown in Figure 3 in that the third element 63 includes a portion extending in the second direction D2.

In the fourth embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the fourth embodiment, a window glass 204 can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W and has improved visibility.

Figure 5 is a diagram showing an example configuration of a vehicle window glass according to the fifth embodiment. In the fifth embodiment, the description of the configuration, actions, and effects similar to those of the above embodiments will be omitted or simplified by incorporating the above description. The window glass 205 shown in Figure 5 differs from the window glass 201 shown in Figure 1 in that the second element 62 and the third element 63 include L-shaped elements.

The second element 62 includes an L-shaped element that includes a portion 62a extending in the second direction D2 and a portion 62b extending in the first direction D1 along the antenna element 71. The antenna element 71 includes a portion that is capacitively coupled to portion 62b. The second element 62 includes an L-shaped element that is bent at the end 85. By including an L-shaped element in the second element 62, the area occupied by the parasitic element 60 can be reduced.

The third element 63 includes an L-shaped element that includes a portion 63a extending in the third direction D3 and a portion 63b extending in a fourth direction D4 opposite to the first direction D1. The third element 63 includes an L-shaped element that is bent at the end 86. By including an L-shaped element in the third element 63, the area occupied by the parasitic element 60 can be reduced.

In the fifth embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the fifth embodiment, a window glass 205 with improved visibility can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W.

Figure 6 is a diagram showing an example configuration of a vehicle window glass according to the sixth embodiment. In the sixth embodiment, the description of the configuration, actions, and effects similar to those of the above embodiments will be omitted or simplified by incorporating the above description. The window glass 206 shown in Figure 6 differs from the window glass 205 shown in Figure 5 in that the third element 63 includes a portion 63a extending in the second direction D2.

In the sixth embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the sixth embodiment, a window glass 206 can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W and has improved visibility.

Figure 7 is a diagram showing an example configuration of a vehicle window glass according to the seventh embodiment. In the seventh embodiment, the description of the configuration, actions, and effects similar to those of the above-described embodiments will be omitted or simplified by incorporating the above description. The window glass 207 shown in Figure 7 differs from the window glass 205 shown in Figure 5 in that the antenna 70 is substantially point-symmetric.

In the seventh embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the seventh embodiment, a window glass 207 can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W and has improved visibility.

Figure 8 is a diagram showing an example configuration of a vehicle window glass according to the eighth embodiment. In the eighth embodiment, the description of the same configuration, actions, and effects as those of the above embodiments will be omitted or simplified by incorporating the above descriptions. The window glass 208 shown in Figure 8 differs from the window glass 206 shown in Figure 6 in that the antenna 70 is upside down. The second element 62 includes an L-shaped element including a portion 62a extending in the third direction D3 and a portion 62b extending in the first direction D1. The third element 63 includes an L-shaped element including a portion 63a extending in the third direction D3 and a portion 63b extending in the fourth direction D4.

In the eighth embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the eighth embodiment, a window glass 208 with improved visibility can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W.

Figure 9 is a diagram showing an example configuration of a vehicle window glass according to the ninth embodiment. In the ninth embodiment, explanations of the configuration, actions, and effects similar to those of the above-described embodiments will be omitted or simplified by incorporating the above explanations. The window glass 209 shown in Figure 9 differs from the window glass 201 shown in Figure 1 in the shape of the second element 62.

The second element 62 includes a portion 62a extending from near the first end 81 in the second direction D2 and a portion 62b extending from near the first end 81 in the third direction D3. The portion 62a extends to the open end 83, and the portion 62b extends to the open end 87.

The third element 63 may include an L-shaped element, similar to the embodiment shown in Figure 5.

9 , the longest length connecting the open end 84 to the open end 83 or the open end 87 is defined as L _P. In this case, if L _P satisfies the above formula 3a, the antenna gain of the antenna 70 in the frequency band W is improved. If the parasitic element 60 does not include the third element 63, the second end 82 becomes an open end, and therefore L _P corresponds to the longest length connecting the second end 82 to the open end 83 or the open end 87.

In the second element 62 shown in Fig. 9 , the length extending from the vicinity of the first end 81 in the second direction D2 to the open end 83 is defined as _L22 , and the length extending from the vicinity of the first end 81 in the third direction D3 to the open end 87 is defined as _L23 . In this case, if _L23 / _L22 is equal to or greater than 0.80 and equal to or less than 1.20, the antenna gain of the antenna 70 in frequency band W is improved. In Fig. 9 , _L22 corresponds to the length of the portion 62a from the first end 81 to the open end 83, and _L23 corresponds to the length of the portion 62b from the first end 81 to the open end 87. The open end 83 is an example of a first open end. The open end 87 is an example of a second open end.

In terms of improving the antenna gain of the antenna 70 in the frequency band W, L ₂₃ /L ₂₂ is preferably equal to or greater than 0.85 and equal to or less than 1.15, and more preferably equal to or greater than 0.90 and equal to or less than 1.10.

In FIG. 9, the antenna element 71 includes a portion extending in the third direction D3, and this portion extends further in the third direction D3 than the first end 81. This increases the length of the portion of the antenna element 71 that is capacitively coupled with both the parasitic element 60 and the end edge 42d, thereby improving the antenna gain of the antenna 70 in the frequency band W.

With the glass plate 43 attached to the vehicle, the distance between the portion of the second element 62 that does not run parallel to the antenna element 71 and the metal portion (in this example, the edge 42d) around the glass plate 43 is defined as d. In this case, d is expressed as follows:
0<d≦0.06×k×λ...Formula 6a
When the above condition is satisfied, the antenna gain of the antenna 70 in the frequency band W is improved.

The antenna gain of the antenna 70 in the frequency band W is improved.
0<d≦0.05×k×λ...Formula 6b
is preferred,
0<d≦0.04×k×λ...Formula 6c
is more preferred.

In the ninth embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the ninth embodiment, a window glass 209 can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W and has improved visibility.

Figure 10 is a diagram showing an example configuration of a vehicle window glass according to the tenth embodiment. In the tenth embodiment, explanations of the configuration, actions, and effects similar to those of the above-described embodiments will be omitted or simplified by incorporating the above explanations. The window glass 210 shown in Figure 10 differs from the window glass 209 shown in Figure 9 in that the third element 63 extends in the second direction D2. The third element 63 may include an L-shaped element, as in the embodiment shown in Figure 6.

In the tenth embodiment, the first element 61 is also a single line that is not connected to any other conductors from the first end 81 to the second end 82, and the antenna element 71 has a portion that runs parallel to and close to the parasitic element 60. Therefore, according to the tenth embodiment, a window glass 210 can be provided that is equipped with an antenna 70 that receives radio waves in a specified frequency band W and has improved visibility.

Figure 11 is a diagram showing an example configuration of a vehicle window glass according to the eleventh embodiment. In the eleventh embodiment, explanations of the configuration, actions, and effects similar to those of the above-described embodiments will be omitted or simplified by incorporating the above explanations. The window glass 211 shown in Figure 11 differs from the window glass 209 shown in Figure 9 in the shape of the third element 63.

The third element 63 includes a portion 63c extending from near the second end 82 in the second direction D2 and a portion 63a extending from near the second end 82 in the third direction D3. The portion 63c extends to the open end 88, and the portion 63a extends to the open end 84.

11 , the longest length connecting the open end 84 or 88 and the open end 83 or 87 is defined as L _P. In this case, if L _P satisfies the above formula 3a, the antenna gain of the antenna 70 in the frequency band W is improved. If the parasitic element 60 does not include the third element 63, the second end 82 becomes an open end, and therefore L _P corresponds to the longest length connecting the second end 82 and the open end 83 or 87.

In the third element 63 shown in FIG. 11 , the length extending from the vicinity of the second end 82 in the second direction D2 to the open end 88 is defined _{as L32} , and the length extending from the vicinity of the second end 82 in the third direction D3 to the open end 84 is defined as _L33 . In this case, if _L33 / _L32 is greater than or equal to 0.80 and less than or equal to 1.20, the antenna gain of the antenna 70 in frequency band W is improved. In FIG. 11 , _L32 corresponds to the length of the portion 63c from the second end 82 to the open end 88, and _L33 corresponds to the length of the portion 63a from the second end 82 to the open end 84. The open end 88 is an example of a third open end. The open end 84 is an example of a fourth open end.

In terms of improving the antenna gain of the antenna 70 in the frequency band W, L ₃₃ /L ₃₂ is preferably equal to or greater than 0.85 and equal to or less than 1.15, and more preferably equal to or greater than 0.90 and equal to or less than 1.10.

Figure 12 shows an example configuration of an antenna 70 mounted on a glass plate 43. The power supply 72 and antenna element 71 may be mounted on a dielectric plate 44 disposed on the glass plate 43, as shown in Figure 12.

The dielectric plate 44 is a layer disposed along the main surface of the glass plate 43. As shown in the figure, the dielectric plate 44 is disposed on a partial region (disposition region) of the main surface of the glass plate 43. The dielectric plate 44 may be in contact with the placement region, or another layer may be present between the dielectric plate 44 and the placement region. The dielectric plate 44 may be a sheet-like or foil-like dielectric.

The antenna 70 may include a coil 30 inserted between the power supply 72 and the antenna element 71. The location where the coil 30 is installed is not limited to the dielectric plate 44, but may be elsewhere, such as the main surface of the glass plate 43.

The coil 30 is a component inserted in series between the antenna element 71 and the conductive member 20. One end of the coil 30 is electrically connected to one end of the antenna element 71, and the other end of the coil 30 is electrically connected to one end of the conductive member 20.

When the antenna 70 includes the coil 30, the length of the antenna element 71 is L _H , the wavelength of the radio wave in the air at the center frequency of the frequency band W received by the antenna element 71 is λ, and the wavelength shortening rate determined by the dielectric plate 44 and the glass plate 43 is k.

In this case, _LH is
0.03×λ×k≦L _H ≦0.18×λ×k...Formula 7a
If the above expression is satisfied, the antenna gain in frequency band W can be ensured even if the length LH of antenna element 71 is shorter than (λ/4)×k. Since the length _LH of antenna element 71 can be made shorter than (λ/4)×k while the antenna gain in frequency band W is ensured, antenna 70 capable of receiving radio waves in frequency band W can be made smaller.

If _LH is less than 0.03×λ×k, the length for the antenna element 71 to resonate favorably is insufficient, making it difficult to ensure antenna gain in frequency band W. If _LH exceeds 0.18×λ×k, the area occupied by the antenna element 71 increases, making it difficult to miniaturize the antenna 70.

In terms of miniaturizing the antenna 70 capable of receiving radio waves in frequency band W,
0.04×λ×k≦L _H ≦0.17×λ×k ...Formula 7b
is preferred,
0.05×λ×k≦L _H ≦0.16×λ×k ...Formula 7c
is more preferred.

When frequency band W is the band of FM broadcast waves (e.g., 76 MHz to 108 MHz), if the inductance of coil 30 is 0.2 μH or more and 1.2 μH or less, antenna 70 equipped with antenna element 71 that satisfies formula 7a above can be made smaller. From the perspective of making antenna 70 capable of receiving radio waves in the band of FM broadcast waves smaller, an inductance of 0.3 μH or more and 1.1 μH or less is preferable, and an inductance of 0.4 μH or more and 1.0 μH or less is even more preferable.

The dielectric plate 44 is a planar layer having a main surface 48 on which the antenna element 71 is formed, and the coil 30 is placed on the main surface 48. By providing the antenna element 71 and coil 30 on the same main surface 48, the antenna 70, which is capable of receiving radio waves in frequency band W, can be made smaller.

The dielectric plate 44 is a layer whose main component is a dielectric. The dielectric plate 44 may be a glass epoxy substrate such as FR4 or CEM3, or may be formed from a resin such as polyimide. Alternatively, the dielectric plate 44 may be formed from a fluororesin such as PET (Polyethylene terephthalate) or PTFE (Polytetrafluoroethylene), or a resin such as LCP (Liquid Crystal Polymer), or PPO (Polyphenyloxide).

By using a thin glass epoxy substrate with a dielectric layer thickness of 0.07 mm to 1.47 mm (nominal thickness: 0.1 mm to 1.3 mm) for the dielectric plate 44, conformability to the curved surface of the glass plate 43 is improved, facilitating the mounting of the coil 30 and the formation of the antenna element 71. To improve conformability to the curved surface of the glass plate 43, the thickness of the glass epoxy substrate is preferably 1.13 mm or less, more preferably 0.89 mm or less, even more preferably 0.58 mm or less, particularly preferably 0.35 mm or less, and most preferably 0.13 mm or less. Furthermore, glass epoxy substrates are less hygroscopic than polyimide substrates, which are known as flexible substrates, improving the weather resistance of the antenna 70 against moisture and other factors.

The antenna element 71 and coil 30 may be provided directly on the glass plate 43 attached to the vehicle body. Alternatively, the antenna element 71 may be formed on the inner layer of the glass plate 43.

The antenna element 71 is not limited to an element attached to a glass plate attached to the vehicle, but may be, for example, a rod antenna extending into the air. A rod antenna is an example of a linear antenna element attached to a vehicle. When the antenna element 71 is a rod antenna, the dielectric adjacent to the antenna element 71 is air, so the wavelength shortening rate k is approximately equal to 1. The antenna element 71 is not limited to a linear antenna conductor, but may also be a plate-shaped antenna conductor.

Figure 13 shows an example of simulation results for antenna gain for vertically polarized waves in the FM broadcast wave band when power is supplied from a power supply unit 72 positioned close to the edge 42b of the glass plate 43, which is located near that side. In the legend, "209" indicates the case of window glass 209 (Figure 9), "211" indicates the case of window glass 211 (Figure 11), and "no parasitic element" indicates the case where the parasitic element 60 is removed from the window glass 209 (Figure 9). Figure 13 shows that adding the parasitic element 60 improves the antenna gain for vertically polarized waves in the FM broadcast wave band.

The conditions for the simulation of FIG. 13 are:
<Window Glass 209 (Fig. 9)>
_LH : 500mm
Length from the first end 81 to the second end 82: 440 mm
Length from open end 83 to open end 87: 680 mm
Length from second end 82 to open end 84: 210 mm
<Window Glass 211 (FIG. 11)>
_LH : 500mm
Length from the first end 81 to the second end 82: 440 mm
Length from open end 83 to open end 87: 680 mm
Length from open end 88 to open end 84: 420 mm
<Without parasitic element 60 (FIG. 9)>
_LH : 500mm
The wavelength shortening rate k was set to 0.67.

Figure 14 shows an example of the simulation results for antenna gain for vertically polarized waves in the FM broadcast wave band when power is supplied from a power supply unit 72 located close to the bottom edge of the glass plate 43, based on the edge 42d that is close to the bottom edge. In the legend, "209" indicates the case with the window glass 209 (Figure 9), and "without parasitic element" indicates the case where the parasitic element 60 is removed from the window glass 209 (Figure 9). Figure 14 shows that adding the parasitic element 60 improves the antenna gain for vertically polarized waves in the FM broadcast wave band.

The conditions for the simulation in Figure 14 were the same as those for the simulation in Figure 13, except for the position of the power supply unit 72.

Figure 15 shows an example of simulation results for antenna gain for vertically polarized waves in the DAB Band III band when power is supplied from a power supply unit 72 located close to the side edge 42b of the glass plate 43, with the edge 42b being the reference point. In the legend, "201" indicates the case with the window glass 201 (Figure 1), and "without parasitic element" indicates the case where the parasitic element 60 is removed from the window glass 201 (Figure 1). Figure 15 shows that adding the parasitic element 60 improves the antenna gain for vertically polarized waves in the DAB Band III band.

The conditions for the simulation of FIG. 15 are:
<Window glass 201 (Fig. 1)>
_LH : 250mm
Length from the first end 81 to the second end 82: 440 mm
Length from first end 81 to open end 83: 340 mm
Length from second end 82 to open end 84: 170 mm
<Without parasitic element 60 (Fig. 1)>
_LH : 250mm
The wavelength shortening rate k was set to 0.67.

Fig _. 16 is a diagram showing an example of the _results of a simulation of changes in the average value of the antenna gain of vertically polarized waves in the FM broadcast wave band, when the maximum average value is set to 0 dB, versus changes in L C /L H in the configuration of Fig. 1. Let L _H be the length of antenna element 71, and L _C be the length of the portion of parasitic element 60 that is capacitively coupled to antenna element 71. Results show that when _{L C} /L _H ≧ 0.14, the antenna gain of antenna 70 in frequency band W is improved.

The conditions for the simulation of FIG. 16 are:
_LH : 500mm (fixed)
Total length of parasitic element 60: 1100 mm (fixed)
Length from the first end 81 to the second end 82: 440 mm (fixed)
Length from the first end 81 to the open end 83: variable Length from the second end 82 to the open end 84: variable Wavelength shortening rate k: 0.67
It was decided.

Figure 17 shows an example of the results of a simulation of the change in the average antenna gain for vertically polarized waves in the FM broadcast wave band relative to the horizontal position of the first element 61 in the configuration of Figure 1, with the maximum average value set to 0 dB. Figure 17 shows that when the horizontal position of the first element 61 is within the range of -0.32 to 0.70, the change in the average antenna gain is within 3 dB.

The conditions for the simulation of FIG. 17 are:
_LH : 500mm (fixed)
Total length of parasitic element 60: 1100 mm (fixed)
Length from the first end 81 to the second end 82: 440 mm (fixed)
Length from the first end 81 to the open end 83: variable Length from the second end 82 to the open end 84: variable Wavelength shortening rate k: 0.67
It was decided.

Figure 18 shows an example of the results of a simulation of the change in the average antenna gain of vertically polarized waves in the FM broadcast wave band as a function of the lateral position of the first element 61 in the configuration of Figure 9, with the maximum average value being 0 dB. Figure 18 shows that when the lateral position of the first element 61 is within the range of -0.20 to 0.81, the change in the average antenna gain is within 3 dB.

The conditions for the simulation of FIG. 18 are:
_LH : 500mm (fixed)
Length from the first end 81 to the second end 82: 440 mm (fixed)
Length from the open end 87 to the open end 83: Varies Length from the second end 82 to the open end 84: Varies Wavelength shortening rate k: 0.67
It was decided.

Figure 19 shows an example of the results of a simulation of the change in the average antenna gain for vertically polarized waves in the FM broadcast wave band versus changes in d/(k×λ) in the configuration of Figure 9, with the maximum average value set to 0 dB. Figure 19 shows that when d/(k×λ) is 0.05 or less, the change in average antenna gain is within 3 dB.

The conditions for the simulation of FIG. 19 are:
_LH : 500mm (fixed)
Length from first end 81 to second end 82: variable Length from open end 87 to open end 83: 680 mm (fixed)
Length from the second end 82 to the open end 84: Change d: Change Wavelength shortening rate k: 0.67
It was decided.

Although the embodiments have been described above, the technology of the present disclosure is not limited to the above embodiments. Various modifications and improvements are possible, such as combining or substituting part or all of the other embodiments.

10 Intermediate section 11 First section end 12 Second section end 20 Conductive member 30 Coil 41 Metal body 42 Opening 42a, 42b, 42c, 42d End edge 43 Glass plate 44 Dielectric plate 60 Parasitic element 61 First element 62 Second element 63 Third element 70 Antenna 71 Antenna element 72 Power supply section 73 Open end 81 First end 82 Second end 201 to 211 Window glass

Claims (27)

A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
The antenna includes a power supply portion and an antenna element electrically connected to the power supply portion.
a parasitic element provided on the glass plate,
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element including a portion connected to a vicinity of the first end and extending in a second direction different from the first direction or a third direction opposite to the second direction;
a third element connected to the vicinity of the second end of the first element and including a portion extending in the second direction or the third direction ,
The first element has an intermediate section of 85% of the length from the first end to the second end to which no other conductor is connected,
The antenna element is located on the opposite side of the second element from the second end side and includes a portion that is capacitively coupled with the second element. 2. The vehicle glazing according to claim 1 , wherein the third element comprises an L-shaped element including the portion extending in the second direction or the third direction and a portion extending in a fourth direction opposite to the first direction. 3. The vehicle window glass according to claim 1 , wherein the third element is provided at a position where it is capacitively coupled to a metal portion around the glass plate when the glass plate is attached to a vehicle. 3. The vehicle window glass according to claim 1 , wherein the third element includes a portion extending in the second direction from a vicinity of the second end and a portion extending in the third direction from a vicinity of the second end. 5. The vehicle window glass according to claim 4, wherein, when a length of the third element extending from a vicinity of the second end in the second direction to a third open end _{is L32} and a length of the third element extending from a vicinity of the second end in the third direction to a fourth open end is _L33 , _L33 / _L32 is 0.80 or more and 1.20 or less. 3. The vehicle window glass according to claim 1, wherein, when the glass plate is attached to a vehicle, the first element includes a portion extending in a direction approximately perpendicular to a horizontal direction, and the second element and the third element each include a portion extending in a substantially horizontal direction. 3. The vehicle window glass according to claim 1, wherein, when the glass plate is attached to a vehicle, the first element includes a portion that extends in a substantially horizontal direction, and the second element and the third element include portions that extend in a direction that is substantially perpendicular to the horizontal direction. 3. The vehicle window glass according to claim 1, wherein the second element includes an L-shaped element including the portion extending in the second direction or the third direction and a portion extending in the first direction along the capacitively coupled portion. When the length of the antenna element is L _H and the length of the portion of the parasitic element that is capacitively coupled with the antenna element is L _C ,
L _C /L _H ≧0.14
3. The vehicle window glass according to claim 1, wherein the following is satisfied: When the length of the antenna element is L _H , the wavelength of radio waves in the air at the center frequency of the predetermined frequency band is λ, and the wavelength shortening rate due to the glass plate is k, L _H is expressed as follows:
0.03×λ×k≦L _H ≦1.30×λ×k
3. The vehicle window glass according to claim 1, wherein the following is satisfied: When the longest length connecting the two open ends of the parasitic element is L _P , the wavelength of radio waves in the air at the center frequency of the predetermined frequency band is λ, the wavelength shortening rate due to the glass plate is k, and n is an integer equal to or greater than 1, L _P can be expressed as follows:
0.70×(λ/2)×k×n≦L _P ≦1.30×(λ/2)×k×n
3. The vehicle window glass according to claim 1, wherein the following is satisfied: A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
The antenna includes a power supply portion and an antenna element electrically connected to the power supply portion.
a parasitic element provided on the glass plate,
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element connected to the vicinity of the first end and including a portion extending in a second direction different from the first direction or a third direction opposite to the second direction,
The first element has an intermediate section of 85% of the length from the first end to the second end to which no other conductor is connected,
the antenna element is located on the opposite side of the second element from the second end side and includes a portion that is capacitively coupled with the second element,
The longest length connecting the two open ends of the parasitic element is L _P , where λ is the wavelength of radio waves in the air at the center frequency of the predetermined frequency band, k is the wavelength shortening rate due to the glass plate, and n is an integer equal to or greater than 1, _P teeth,
0.70×(λ/2)×k×n≦L _P ≦1.30×(λ/2)×k×n
This vehicle window glass satisfies the above requirements. 3. The vehicle window glass according to claim 1 , wherein the second element includes a portion extending in the second direction from a vicinity of the first end and a portion extending in the third direction from a vicinity of the first end. 12. The vehicle window glass according to claim 11, wherein, when a length of the second element extending from a vicinity of the first end in the second direction to the first open end _{is L22} and a length of the second element extending from a vicinity of the first end in the third direction to the second open end is _L23 , _L23 / _L22 is 0.80 or more and 1.20 or less. The vehicle window glass according to claim 13, wherein the antenna element extends in the third direction beyond the first end. When the glass plate is attached to a vehicle, the distance between the portion of the second element that does not run parallel to the antenna element and the metal portion around the glass plate is d, the wavelength of radio waves in the air at the center frequency of the predetermined frequency band is λ, and the wavelength shortening rate due to the glass plate is k. Then, d is expressed as follows:
0<d≦0.06×k×λ
14. The vehicle window glass according to claim 13, which satisfies the following: When the glass plate is attached to a vehicle, the metal portion on the periphery of the glass plate includes a first end side in the third direction and a second end side in the second direction,
When the center position between the first end side and the second end side is represented as 0, the position of the first end side is represented as −1, and the position of the second end side is represented as +1,
3. The vehicle window glass according to claim 1 , wherein the first element includes a portion located within a range of -0.3 to +0.8. A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
The antenna includes a power supply portion and an antenna element electrically connected to the power supply portion.
a parasitic element provided on the glass plate,
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element connected to the vicinity of the first end and including a portion extending in a second direction different from the first direction or a third direction opposite to the second direction,
The first element has an intermediate section of 85% of the length from the first end to the second end to which no other conductor is connected,
the antenna element is located on the opposite side of the second element from the second end side and includes a portion that is capacitively coupled with the second element,
When the glass plate is attached to a vehicle, the metal portion on the periphery of the glass plate includes a first end side in the third direction and a second end side in the second direction,
When the center position between the first end side and the second end side is represented as 0, the position of the first end side is represented as −1, and the position of the second end side is represented as +1,
The first element includes a portion located within a range of -0.3 to +0.8, e.g., a vehicle window glass. The vehicle window glass according to claim 1 or 2 , wherein the power supply portion and the antenna element are provided on the glass plate. The vehicle window glass according to claim 1 or 2 , wherein the power supply portion and the antenna element are provided on a dielectric plate disposed on the glass plate. A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
The antenna includes a power supply portion and an antenna element electrically connected to the power supply portion.
a parasitic element provided on the glass plate,
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element connected to a portion near the first end and including a portion extending in a second direction different from the first direction or a third direction opposite to the second direction,
The first element has an intermediate section of 85% of the length from the first end to the second end to which no other conductor is connected,
the antenna element is located on the opposite side of the second element from the second end side and includes a portion that is capacitively coupled with the second element,
The vehicle window glass, wherein the power supply portion and the antenna element are provided on a dielectric plate disposed on the glass plate. The vehicle window glass according to claim 1 or 2 , wherein a coil is inserted between the power supply portion and the antenna element. A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
The antenna includes a power supply portion and an antenna element electrically connected to the power supply portion.
a parasitic element provided on the glass plate,
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element connected to a portion near the first end and including a portion extending in a second direction different from the first direction or a third direction opposite to the second direction,
The first element has an intermediate section of 85% of the length from the first end to the second end to which no other conductor is connected,
the antenna element is located on the opposite side of the second element from the second end side and includes a portion that is capacitively coupled with the second element,
A vehicle window glass, wherein a coil is inserted between the power supply portion and the antenna element. 3. The vehicle window glass according to claim 1 , wherein the antenna receives FM broadcast waves. 3. The vehicle window glass according to claim 1 , wherein the antenna receives radio waves of DAB Band III. A glass plate and
an antenna for receiving radio waves in a predetermined frequency band,
The antenna includes a power supply portion and an antenna element electrically connected to the power supply portion.
a parasitic element provided on the glass plate,
The parasitic element is
a first element extending in a straight line in a first direction from a first end to a second end of the central portion of the glass sheet;
a second element connected to a portion near the first end and including a portion extending in a second direction different from the first direction or a third direction opposite to the second direction,
The first element has an intermediate section of 85% of the length from the first end to the second end to which no other conductor is connected,
the antenna element is located on the opposite side of the second element from the second end side and includes a portion that is capacitively coupled with the second element,
The vehicle window glass, wherein the antenna receives radio waves of DAB Band III. The vehicle window glass according to claim 1 or 2 , wherein the glass plate is used as a side glass.