JPS593494Y2 - discharge lamp - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a discharge lamp in which a high-frequency electric field excites metal vapor sealed inside the bulb to emit light.

Conventionally, a light-emitting metal is enclosed in a bulb, and when the vapor of the light-emitting metal is excited using a high-frequency electromagnetic field generated by a high-frequency coil, ultraviolet light is emitted, and this ultraviolet light is converted into visible light by a phosphor coating. Discharge lamps that emit light are known.

However, this type of conventional discharge lamp has the disadvantage that high frequency noise leaks from the discharge lamp body to the outside, making it impossible to put it to practical use.

This idea was made to eliminate the above-mentioned drawbacks, and it prevents high-frequency noise from leaking to the outside.
An object of the present invention is to provide a discharge lamp that can obtain sufficient luminous flux.

Embodiments of this invention will be described below with reference to the drawings.

The figure is a sectional view showing an embodiment of the discharge lamp according to this invention.
In the figure, reference numeral 1 denotes a bulb made of a light-transmitting material such as glass, and having a cylindrical portion 2, for example, which protrudes inward from the peripheral wall.

In this case, although not shown, a predetermined amount of vapor of a light-emitting metal such as mercury that emits ultraviolet light when excited by a high-frequency electric field is sealed in the bulb 1, and an inert gas such as argon is also sealed in the bulb 1. has been done.

3 is an outer conductor formed to cover the outer periphery of the bulb 1;
5 is an inner conductor inserted into the cylindrical portion 2, and 5 is a fluorescent material coated on the inner surface of the bulb 1, which converts ultraviolet rays into visible light.

6 is a high frequency oscillator whose output end is connected to the outer conductor 3 and the other end is connected to the inner conductor 4.

In the discharge lamp of this invention configured as described above, the high frequency voltage generated by the high frequency oscillator 6 is applied between the outer conductor 3 covering the outer periphery of the bulb 1 and the inner conductor 4 inserted into the cylindrical part 2. and generates a high frequency electric field within the bulb 1.

This high-frequency electric field acts on the luminescent metal sealed inside the bulb 1, excites the vapor of this metal, and causes it to emit ultraviolet light. It is converted into light and emits light.

In this case, the high frequency voltage generated by the high frequency oscillator 6 is applied between the outer conductor 3 and the inner conductor 4, so that the high frequency electric field is generated within the space surrounded by the outer conductor 3 and the inner conductor 4, that is, within the bulb 1. Occurs only in

Therefore, no high frequency electric field is generated on the surface of the outer conductor 3 opposite to the inner conductor 4 side, and no leakage of high frequency noise to the outside occurs.

Note that the outer conductor 3 is preferably formed of a transparent conductive film or a metal net in order to efficiently radiate the visible light converted by the phosphor 5 to the outside of the bulb 1.

Further, the inner conductor 4 may have a hollow cylindrical shape to reduce weight, or may be formed by vapor-depositing a conductor such as metal on the inner periphery of the cylindrical portion 2.

Furthermore, since the outer conductor 3 becomes a live part, it is also effective to protect the live part by covering its outer periphery with a transparent insulating film or by embedding the outer conductor 3 on the outer surface of the bulb 1. be.

It is also effective to make the outer shape of the bulb 1 substantially spherical, which approximates an incandescent light bulb.

As mentioned above, according to this invention, since the high frequency electric field is generated only inside the bulb 1, leakage of high frequency noise to the outside can be prevented, and a sufficient luminous flux can be obtained. .

[Brief explanation of the drawing]

The figure is a sectional view showing an embodiment of the discharge lamp according to this invention. 1... Valve, 2... Cylindrical part, 3...
...Outer conductor, 4...Inner conductor, 5...
...Fluorescent material, 6...High frequency oscillator. Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (4)

[Scope of utility model registration request] (1) A bulb whose inner surface is coated with a phosphor, which is filled with at least metal vapor and inert gas, and which has a cylindrical portion that protrudes inward from the peripheral wall; It is characterized by comprising an outer conductor for covering and an inner conductor provided in the cylindrical part, and by applying a high frequency voltage between the outer conductor and the inner conductor, a discharge is generated and light is emitted. discharge lamp. (2) The discharge lamp according to claim 1, wherein the bulb has a substantially spherical outer shape. (3) The discharge lamp according to claim 1, wherein the outer conductor is a transparent conductive film or a metal mesh. (4) The discharge lamp according to claim 1, wherein the outer conductor is covered with a transparent insulating film or embedded in the outer surface of the bulb.