JPS61244101A - Glass antenna for television mounted on automobile - Google Patents

Abstract

PURPOSE:To improve a sensitivity and a directivity characteristic by providing a glass plate with a conductive film which has a specific area resistance value as a television antenna element. CONSTITUTION:The glass plate is provided with the conductive film which has a 4OMEGA-10kOMEGA, preferably, 25kOMEGA-1kOMEGA/square and a current collection part is formed this conductive film. When the area resistance value decreases below 4OMEGA/square, problems of light beam transmissivity and manufacture are generated and the film becomes too thick, which is not preferable. When the value increases above 10kOMEGA/square, the function of the antenna is not obtained, which is not preferable either.

Description

[Detailed Description of the Invention] [Technical Field] The present invention is suitable for use in television receivers mounted on automobiles.
It concerns the lath antenna.

[Description of prior art] As a TV receiving antenna for use in automobiles.

As shown in Figure S6, two antennas 10.20 each consisting of several elements are attached to the left and right sides of the roof 4o of the automobile body 30, and a space diversity receiving antenna device using these two antennas 10.20 is constructed. Are known. However, this type of antenna has a bad appearance and is dangerous because the two antennas 10 and 20 consisting of several elements protrude from the upper part of the vehicle body 3o, and also generates wind noise when driving at high speed. They have drawbacks such as being easily damaged by mischief when parking, getting caught in a garage, and being expensive.

[Object of the invention] The present invention has good sensitivity characteristics and directivity characteristics, and
It is an object of the present invention to provide an antenna for a television receiver mounted on an automobile without forming a protrusion from the outer shell of the current vehicle.

[Structure of the Invention] The present invention was invented as a result of studies based on the above object, and the gist thereof is to provide a glass plate with a sheet resistance value of 4Ω/□.
The present invention relates to a glass antenna for a television mounted on an automobile, characterized in that a conductive film of ~10 KΩ/□ is provided, and a current collecting portion is formed on the conductive film.

[Description of Examples] Hereinafter, the present invention will be explained in detail with reference to the drawings. In Figure 0, 1 is a car, 2 is a window glass plate of the car, and 2a is a front window glass.

2b is a rear window glass, 2C is a side window glass, 2d is a roof window glass, 3 is a conductive film as an antenna element, and 4 is a current collector.

In the present invention, as illustrated in FIG.
The conductive film 3 as the antenna element of the present invention can be provided on any of the glass plates 2 of various parts of the automobile, such as rear windows, side windows, roof windows, etc.

A conductive film as an antenna element of the present invention.

A resistance value obtained based on the results of research on a conductive film that can receive VHF and/or UHF J-Level broadcasting with desired performance, that is, a sheet resistance value of 4Ω/□ to 10 KΩ/□, more preferably 25Ω/ It has a sheet resistance value of □ to IKΩ/mouth.

If the area resistance value is less than 4 Ω/□, it is not preferable because it causes problems in light transmittance, manufacturing problems, or becomes unnecessarily thick, and if it exceeds 10 KΩ/□, it will no longer function as an antenna. Further, the conductive film as an antenna element of the present invention, which is not preferable, has a width of 1 mm or more and a width of 30 m.
At least one portion includes a portion with a length of m or more. By including a portion with such an area in the conductive film, it can better serve as an antenna.

The area resistance value is 4Ω/□~10KΩ/□ and the width is 1
It is noteworthy that a conductive film containing a portion with a length of 30 layers or more can provide sufficient performance as a television reception antenna.

The reason for this is thought to be that if the width is too narrow or the length is too short, electromagnetic waves in the desired frequency range will not resonate with the antenna.

In addition, a conductive film containing at least one part with a width of 1 mm or more and a length of 3A or more is defined as a conductive film with a sheet resistance of 4Ω/CI-IQKΩ10 of at least 1 mm in width and 1 mm in length. It is sufficient that a 30 mm rectangular conductive film portion exists. The example shown in FIG.
5Ω/mouth), and the example shown in Fig. 3 is
A trapezoidal conductive film including a rectangular part A with a width of 5 layers and a length of 30 layers (4000 layers vertically, 9000 layers horizontally, 9 area resistance 15
The example shown in FIG. 4 is a triangular conductive film (height: 30c layers, sheet resistance value: 500 This is an example in which Ω/mouth) is formed. In the case of conductive films as shown in Figures 3 and 4, the area resistance value is 5Ω/□~I over the entire conductive film.
It is preferable to set it as OKΩ/hole, but in some cases, in addition to the rectangular part of the prescribed 1mm width and 30m length layer, there may be a low area area smaller than 5Ω/hole, or a low area of 5Ω larger than 10Ω. There may be a portion of sheet resistance value.

The position of the conductive film as an antenna element within the glass is determined depending on the location in the automobile of the glass plate to which it is provided, and further depending on the reception performance.
When an opaque conductive film is provided on a glass plate, its position must be determined so as not to obstruct the driver's and passengers' vision, and in the case of a rear window glass equipped with an energized heater for defogging. can be provided in a blank area where the defrosting energizing heater is not provided, for example, an upper blank area or a lower blank area. Note that the conductive film may be provided so as to cover all or most of the glass plate, or may be provided partially.

In the present invention, the conductive film as the antenna element provided on the glass plate may be a transparent conductive film, and the opaque conductive film may be a transparent conductive film, Such a transparent conductive film, which may be an opaque main film, may be, for example, a transparent tin oxide conductive film doped with Sb, a transparent indium oxide conductive film doped with Sn, or Or.

Typical examples include transparent metal conductive films such as Ti, Ag, Au, AI, On, and old, and transparent alloy conductive films such as Ni-0r and SOS, but are of course not limited to these. Transparent metal oxide films, transparent metal or alloy conductive films, or other transparent metal compound films can also be used. Such a transparent metal conductive film may be a single layer, or may be laminated into two or more layers, or may be laminated with transparent films made of various materials to improve durability or optical characteristics. Such a transparent conductive film may be formed directly on the surface of a glass plate by an appropriate film forming method such as a vacuum evaporation method, a sputtering method, a CVD method, a spray method, a CBC method, or a printing method, or it may be formed on a transparent plastic. A transparent conductive film is formed on the film surface by the same method as described above, and this plastic film with a transparent conductive film is laminated with a glass plate to serve as an antenna glass. In addition, an opaque conductive film can be formed by printing a conductive glass frit paste containing conductive metal powder such as Ag powder or A1 powder, glass frit, and Pai Goo on a glass surface and baking it. opaque conductive film or Ag
.

Examples include an opaque conductive film formed by printing and baking a conductive resin paste containing a conductive powder such as A1 or C and a thermosetting resin such as an epoxy resin on a glass surface.

The thickness of the conductive film is determined so that the sheet resistance value is 4Ω/CJ-10 or Ω/hole.

A glass plate with a conductive film formed thereon or a glass plate laminated with a transparent conductive film-coated plastic film may be used as a single plate, or in order to improve safety or to improve the durability of the conductive film. Another glass plate and a laminated interlayer film such as a polyvinyl butyral film or a polyurethane film may be laminated so that the conductive film is enclosed inside, and the glass plate with such a conductive film formed thereon may be used as a laminated glass. In some cases, the conductive film for antennas of the present invention is applied to the front window glass or rear window glass of an automobile, where appropriate transparency is selected according to the design, and appropriate coloring may be applied as desired. Since there is a rule that this type of glass plate must have a visible light transmittance of 70% or more, a transparent conductive film that can obtain a transmittance of 70% or more must be used.

In addition, as shown in FIGS. 1 to 5, a collection made of a material having higher conductivity than the conductive film is placed on a desired portion of the transparent conductive film of the glass plate on which the conductive film of the present invention is formed, for example, at the periphery. A power section 4 is formed, and an antenna feeder line 5 is attached to the current collection section 4 via a power supply terminal, a solder layer, a conductive adhesive layer, or the like. The current collector 4 is made of a conductive material such as a conductive paste, a conductive adhesive, a cylinder, aluminum foil, or a copper mesh wire. Further, the current collecting portion 4 may be formed into an appropriate shape such as a rectangular shape, an island shape such as a circular shape, or a band shape as desired. The current collector 4 may extend over one side or more of the glass plate, or may be provided at several locations.

According to the present invention, the voltage induced in the conductive film 3 is 1. The electromotive force first flows to the highly conductive current collector 4, where the induced voltage is guided to the antenna feeder line 5, and then supplied to the television receiver. Note that a high frequency amplification circuit and/or a matching circuit may be provided on the antenna feeder line 5 or the receiver side in order to improve reception sensitivity or impedance matching.

In addition, in the present invention, the pattern of the conductive film having a width of at least 11 layers and a length of 30 m or more as an antenna element of a glass antenna provided on the window glass of an automobile is based on the shape of the automobile and the shape of the glass plate. Optimal gain, omnidirectional or desired directivity as a TV glass antenna depending on size, shape, etc., especially VHF and/or U
A pattern is selected that provides omnidirectional or desired directivity and sufficient gain when receiving radio waves in the HF television broadcasting frequency band. The examples shown in FIGS. 2 to 4 are rectangular, two-trapezoidal, and triangular conductive films, but the present invention is not limited to these examples, and other polygonal shapes, band-like shapes, fan-like shapes, and radial shapes can be used.

Circular shapes and various other irregular shapes can also be used. The antenna elements that make up this glass antenna include VHF
The antenna conductor may have a pattern that has a high gain for both VHF and UHF television broadcast waves and co-operates with both VHF and UHF television broadcast waves, or the antenna conductor mainly receives VHF television broadcast waves. The pattern may be divided into a part that mainly receives VHF and UHF TV broadcast waves, and a pattern that receives both VHF and UHF TV broadcast waves, or a part that mainly receives VHF and UHF TV broadcast waves and a part that mainly receives VHF TV broadcast waves. VHF divided into the main receiving part
It is also possible to adopt a pattern in which both UHF and UHF broadcast waves are received.

In addition, at the same time as receiving TV broadcast waves, FM and/or AM
The pattern may be designed so that radio broadcasts can also be received.

The results of performance tests conducted on the TV antenna of the present invention shown in FIGS. 2 to 4 are as follows.

As described above, according to the present invention, a glass television antenna with excellent gain and directivity can be obtained. In particular, if the conductive film serving as the antenna element is a transparent conductive film, a transparent glass antenna can be obtained, which can be applied to parts of automobiles where transparency is required. In particular, if the visible light transmittance of the glass antenna with a transparent conductive film is 70% or more, it can be applied to the front window or rear window of an automobile. Furthermore, since such a transparent conductive film is highly transparent and inconspicuous, it is possible to form a pattern more freely than with an opaque conductive film, and a high-quality glass antenna can be obtained.

[Brief explanation of drawings]

FIG. 1 is a plan view of an automobile to which the present invention is applied;
Figure 5 is a front view of a glass antenna according to the present invention, Figure 5 is a perspective view of a vehicle incorporating a conventional vehicle-mounted TV antenna device, and Figure 6 is a cross-sectional view of a glass antenna according to an embodiment of the present invention. shows. 1-Automobile, 2-Glass plate, 3: Conductive film, 4: Current collector. Figure 1 Part 2

Claims (3)

[Claims] (1) A glass antenna for a television mounted on a car, characterized in that a conductive film having a sheet resistance value of 4Ω/□ to 10KΩ/□ is provided on a glass plate as a television antenna element, and a current collecting portion is formed on the conductive film. (2) The glass antenna for a television mounted on a vehicle as set forth in claim 1, wherein the conductive film includes at least one portion having a width of 5 mm or more and a length of 30 mm or more. (3) The glass antenna for a television mounted on a vehicle as set forth in claim 1, wherein the conductive film has transparency.