THIN ANTENNAS

Abstract: The present invention relates to a thin antenna in which an eletric conductor (20) of a helical shape is formed at a thin plate (10). The thin antenna has a construction that the thin plate (10) composed of an insulating material has a predetermined length and width, on which the electric conductor (20) of a helical shape is formed in the longitudinal direction through the front and rear of the thin plate (10). Accordingly, the antenna of the present invention provides convenience in use and an improved effect of a receiving gain.

Description: THIN ANTENNAS TECHNICAL FIELD The present invention relates to a thin antenna, and more particularly a thin antenna which forms an electric conductor in a helical shape on a thin plate composed of a non-conductive material. BACKGROUND ART Generally, a whip antenna has been used as an antenna for personal vehicles. Such a whip antenna has drawbacks that produces a severe noise and causes breakdown due to an effect of the wind during vehicle' s travelling to thereby shorten its lifetime. Furthermore, when the antenna is used for a long time, there are caused problems that the degree of its reception is reduced and the antenna gets out of order, due to insertion of different external substances between antenna poles protruded onto the outside of the vehicle. Recently, a glass antenna formed with hot wires at the rear window of the vehicle is being used. However, the glass antenna has problems such as reduction of a directional receiving characteristic according to a travelling direction of the vehicle as well as complexity in design based on the exterior of the vehicle, which cause greater expenses. DISCLOSURE OF INVENTION To solve the above problems, it is an object of the present invention to provide a thin antenna. Another object of the present invention is to provide a compact lightweight thin antenna to achieve the lightness of vehicles. Other object of the present invention is to provide an antenna which no noise is generated during operating like a power antenna. Still other object of the present invention is to provide an antenna with no loss of battery due to dark current, and easy maintenance and repairs when the antenna is not operated To accomplish the above object of the present invention, there is provided a thin antenna, the antenna comprising: a thin plate composed of an insulating material, having a predetermined length and width; and an electric conductor of a helical shape formed in the longitudinal direction through the front and rear of the thin plate. Thin plate comprises a plurality of holes formed at both edges of the thin plate in the longitudinal direction, which are coated with a conductive material, in which the plurality of the holes are positioned opposite to each other in an approximately slash on both sides of the thin plate, and are connected with the electric conductor so that one single conductive path is made in the longitudinal direction from one end to the other end of the thin plate. BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing a thin antenna according to a preferred embodiment of the present invention; FIG. 2 is a sectional view taken along a line I-I of FIG. 1 ; FIG. 3 is an enlarged perspective view showing the front portion of part "A" of FIG. 1; FIG. 4 is an enlarged perspective view showing the rear portion of part "A" of FIG. 1; FIG. 5 is a perspective view showing a thin antenna according to another embodiment of the present invention; and FIG. 6 is a graph comparing signal gains in a broadcasting frequency. BEST MODE FOR CARRYING OUT THE INVENTION A preferred embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a perspective view showing a thin antenna according to a preferred embodiment of the present invention, FIG. 2 is a sectional view taken along a line I ~ I of FIG. 1, FIG. 3 is an enlarged perspective view showing the front portion of part "A" of FIG. 1, and FIG. 4 is an enlarged perspective view showing the rear portion of part "A" of FIG. 1. As shown, the thin antenna of the present invention comprises a thin plate 10 having a predetermined length and width, which is composed of an insulating material. The thin plate 10 includes an electric conductor 20 of a helical shape formed into the longitudinal direction at the front and rear thereof. The thin plate 10 includes a plurality of holes 12 on both of edges along the longitudinal direction of the thin plate 10, which are coated with a conductive material. Each of the holes 12 positioned opposite to each other in an approximately slash at the front and rear of the thin plate 10 is connected with the electric conductor 20. At this time, the conductor 20 connects the holes 12 so that one single conductive path is made in the longitudinal direction from one end to the other end of the thin plate 10. Thus, since the conductor 20 forming one conductive path is alternately connected to the front and rear of the thin plate 10 through the holes 12 which are coated with a conductive material, the conductor 20 becomes a helical shape. In order to produce the thin antenna of the present invention, a film is prepared, of which double faces covered with epoxy or synthetic resins are coated with a conductive material such as aluminum or copper, and then the coated double -faced film is corroded so as to form a coil- shaped pattern. Next, edges of the pattern are drilled and coated with the conductive material, to thereby obtain both faces in a helical form by combination of the conductive patterns. As another manufacturing method, a plurality of holes are formed on a synthetic resin coated with no conductors in a predetermined interval, and the both sides thereof is printed using conductive ink such as silver to generates an antenna pattern. It is preferable that the width of the thin plate 10 is 10 approximately 3 ~ 20mm , and the length thereof is 10 ~ 300mm for the antenna. It is also preferable that an interval W between the holes 12 is 1 ~ lOmm . Reference numeral 30 indicates a connection line for connecting the conductive path of the antenna to a mounting member. FIG. 5 is a perspective view showing a thin antenna according to 15 another embodiment of the present invention. This embodiment has the same construction as that of FIG. 1, but has an arrangement that the electric conductor 20 is extended to one end of the antenna, in place of the connection line 30 of FIG. 1. Further, am amplifier 40 for amplifying a signal is integrally incorporated at the extended end 20 of the electric conductor 20. FIG. 6 is a graph comparing signal gains in frequency band of a broadcasting signal. In FIG. 6, A indicates a receiving signal gain with regard to the antenna of the present invention, and B shows a gain with regard to the conventional whip antenna. As we can see 25 from FIG. 6, the gain of the antenna according to the present invention is further improved. As described above, the thin antenna in accordance with the present invention provides various advantages that improves a signal gain, achieve a compact lightweight antenna, and gives convenience in on use as well as easiness m maintenance and repairs. INDUSTRIAL APPLICABILITY A thin antenna of the present invention is used for personal vehicles.

Claims: WHAT IS CLAIMED IS : 1. A thin antenna, comprising: a thin plate (10), composed of an insulating material, having a predetermined length and width; and an electric conductor (20) of a helical shape formed in the longitudinal direction through the front and rear of said thin plate (10). 2. The thin antenna as claimed in claim 1, wherein said thin plate (10) comprises a plurality of holes (12) formed at both edges of said thin plate (10) in the longitudinal direction, which are coated with a conductive material, wherein the plurality of said holes (12) are positioned opposite to each other in an approximately slash on both sides of said thin plate 10, and are connected with said electric conductor (20) so that one single conductive path is made in the longitudinal direction from one end to the other end of said thin plate (10). 3. The thin antenna as claimed in claim 1, wherein the width of said thin plate (10) is approximately 3 ~ 20mm , and the length thereof is 10 - 300mm . 4. The thin antenna as claimed in claim 1, wherein the interval between said holes (12) is l ~ 10mm . 5. The thin antenna as claimed in claim 1 or 2, wherein said electric conductor (20) is wired in the opposite direction at the middle point for impedance matching. 6. The thin antenna as claimed in claim 1 or 2, wherein an electric conductor is extended to one end of said antenna. 7. The thin antenna as claimed in claim 6, further comprising an amplifier which is integrally incorporated with said electric conductor.

Inventors: JUNG SOON JO, JUNG, SOON, JO
Applicants: JUNG SOON JO, JUNG, SOON, JO
Application year: 1996
Main classification: H01Q1
IPC codes: H01Q1, H01Q9, H01Q11