JPS62281256A - Rare gas discharge lamp device - Google Patents

Abstract

PURPOSE:To uniformize a distribution of illumination in the axial direction of a bulb, by forming an aperture having no phosphor film in the axial direction and then almost uniformly drawing the nearly whole-length positive column inside the bulb toward an auxiliary electrode disposed on the outer bulb surface diametrically facing to the aperture and in the axial direction. CONSTITUTION:An auxiliary electrode 16 in a thin rectangular plate shape is disposed on a prescribed outer surface position of a bulb 13 so that it is put closely over the nearly whole length of the bulb 13. One end of this auxiliary electrode 16 is electrically connected with a high-frequency lighting circuit 11, and then its potential difference is generated against a positive column 18 by impressing definite potential. A phosphor screen 14, which is on the opposite side of the auxiliary electrode 16, that is, diametrically facing to the auxiliary electrode 16, and which is on the inner surface of the bulb 13, is excluded with definite width over the nearly whole length in the axial direction of the bulb 13, so that an aperture 17 is formed. Discharge is performed between a pair of electrodes 15a and 15b to almost uniformly draw the positive column 18 over the nearly whole length toward the auxiliary electrode 16. Hence, a distribution of illumination can be obtained almost uniformly over the nearly whole length of the aperture 17.

Description

Detailed Description of the Invention 3. Detailed Description of the Invention [Object of the Invention] (Industrial Application Field) The present invention is directed to a rare gas discharge lamp having a rare gas discharge lamp that emits a gas whose main component is xenon gas. The present invention relates to electric lighting devices, and particularly to a rare gas discharge lamp device in which an aperture 17 and an auxiliary electrode are provided in a rare gas discharge lamp.

(Prior art) In general, rare gas discharge lamps have a thin bulb outer diameter, and because they use rare gas discharge, brightness and discharge voltage are hardly affected by ambient temperature, have a long life, and are made using different types of phosphor in the phosphor film. It has the advantage of being able to select various light colors depending on the situation.

Therefore, this type of rare gas discharge lamp is used for so-called office automation (OA) such as PPC copy halls and facsimile machines.
These OA
Efforts are being made to make devices smaller and maintenance-free.

However, the noble gas Iln? In order to emit light efficiently, LF lamps contain gas such as xenon in the bulb at several tens of torr.
It is sealed under high pressure of several hundred torr.

For this reason, the positive column inside the bulb becomes thin, for example, about 1 m+ or less, and there is a drawback that there is a large difference in brightness depending on the distribution state of the positive column inside the bulb, resulting in uneven brightness.

That is, the phosphor film at a location close to a small-diameter positive column emits very strong light and becomes bright, but at a location away from the positive column, the light emission becomes weak and dark.

Therefore, the uneven brightness of this rare gas discharge lamp is a major drawback as a document reading light source that requires a substantially uniform illuminance distribution along the axial direction of the bulb.

Figure 6 shows a longitudinal cross-sectional view of a conventional rare gas discharge lamp.
A phosphor film 2 made of phosphor is coated almost entirely on the inner circumferential surface of a straight cylindrical bulb 1 over almost the entire axial direction.

A gas containing xenon (Xe) as a main component is sealed in the bulb 1 at a high pressure of, for example, about 90 to 110 torr, and a pair of electrodes 3a are provided at both left and right ends of the bulb 1.

3b are each sealed.

Furthermore, auxiliary electrodes 4 in the form of elongated rectangular plates are attached to required locations on the outer surface of the bulb 1 in close contact over almost the entire length of the bulb 1, and one end of the auxiliary electrode 4 is attached to a pair of electrodes 3a. ,3
It is electrically connected to the required one of b.

Then, when a high frequency current of, for example, about 30 KHz is passed between the pair of electrodes 3a and 3b, the electrode 3a.

3b, and a small diameter positive column 5 is formed inside the bulb.

However, this positive column 5 is distributed as shown in FIG. At one end of the auxiliary electrode 4, which is attracted to the phosphor film 2 on the side of the auxiliary electrode 4 and is electrically connected to the electrode 3a, the potential of the positive column 5 and the potential of the auxiliary electrode 4 at this part are Since they are almost the same, the positive column 5 is not attracted to the auxiliary electrode 4, but is distributed almost at the axial center of the bulb 1, and is spaced apart from the phosphor film 2.

For this reason, one end of the bulb 1 in the axial direction becomes darker than the middle thereof, resulting in a drawback that the illuminance distribution of the bulb 1 becomes significantly uneven in the axial direction.

FIG. 7 shows a longitudinal sectional view of another conventional example, which shows that the auxiliary electrode 4 is replaced with the electrode 3a in the conventional example described above.

It is simply attached to the outer surface of the bulb 1 in close contact with it without being electrically connected to one of the bulbs 3b.

In this conventional example, the small diameter positive column 5 is as shown in FIG.
It meanders in a waveform along the axial direction of the valve 1.

This is supplementary 1ff! 4 is electrically floating, charges accumulate in the center of the auxiliary electrode 4, and this charge eliminates the potential difference with the positive column 5, causing the positive column 5 to meander.

That is, the positive column 5 is distributed approximately at the axial center of the bulb 1 in the axially intermediate portion of the bulb 1 and is spaced apart from the phosphor film 2;
On both sides, the phosphor film 2 is attracted to the auxiliary electrode 4.
close to.

Therefore, in this conventional example, the axially middle part of the bulb 1 is darker than the both sides thereof, and the illuminance distribution of the bulb 1 becomes significantly uneven in the axial direction.

(Problems to be Solved by the Invention) As described above, the conventional rare gas discharge lamp shown in FIGS. 6 and 7 has a drawback in that the illuminance distribution of the bulb 1 is uneven in the axial direction.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a rare gas discharge lamp device in which the illuminance distribution is substantially uniform in the axial direction.

[Structure of the Invention] (Means for Solving the Problems) The present invention provides a rare gas release system in which a phosphor film made of a phosphor is coated on the inner surface of a bulb and a gas containing xenon gas as a main component is sealed therein. In a rare gas discharge lamp device having an electric lamp, an aperture that lacks the phosphor film is provided along the axial direction of the bulb, and an auxiliary electrode is provided along the axial direction on the outer surface of the bulb diametrically opposed to the aperture. The auxiliary electrode is attached to the auxiliary electrode so that almost the entire length of the positive column inside the bulb is almost evenly attracted to this auxiliary electrode.

(Operation) When a pair of electrodes of a rare gas discharge lamp are energized, almost the entire length of the positive column within the bulb is drawn almost evenly to the auxiliary mandrel.

Therefore, since the solar column approaches the phosphor film in the bulb on the side where the auxiliary electrode is attached almost evenly over almost the entire length, the light is emitted almost equally and strongly over the entire length, and the brightness increases. The illuminance distribution from the seven vertices of the bulb diametrically opposed to the auxiliary electrode becomes approximately uniform in the axial direction.

(Example) Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 5. In addition, in the drawings, common parts are given the same reference numerals, and redundant explanation thereof will be omitted.

FIG. 1 shows the overall configuration of an embodiment of the present invention, in which a rare gas discharge lamp 12 is electrically connected to an AC power source 10 such as a commercial power source via a high frequency lighting circuit 11.

The rare gas discharge lamp 12 is constructed as shown in FIGS. 2 and 3, and includes, for example, a straight cylindrical glass bulb 13 with 1. A phosphor film 14 made of phosphor is coated over almost the entire length in the axial direction.

For example, 90% of the gas containing xenon (Xe) as the main component, krypton (Kr), and helium (He) is contained in the bulb 1.
A pair of Ti electrodes 15a are placed at both left and right ends of the valve 13.

15b, and a high frequency lighting circuit 11 shown in FIG. 1 is electrically connected to these electrodes 15a and 15b.

In addition, auxiliary electrodes 16 in the form of elongated rectangular plates are provided at required locations on the outer surface of the bulb 13, covering almost the entire length of the bulb 13! One end of this auxiliary electrode 16 is electrically connected to the high frequency lighting circuit 11 as shown in FIG. It has become.

A valve 13 on the opposite side of this auxiliary electrode 16, that is, diametrically opposed to the auxiliary electrode 16 as shown in FIG.
The inner phosphor II! J14 is cut out to a required width along the axial direction of the valve 13 over almost the entire length to form an aperture 17.
17 is opened.

Next, the operation of this embodiment will be described.

When lighting the rare gas discharge lamp 12, the high frequency lighting circuit 1
1, the power frequency of AC power 11i10 is set to 30, for example.
The high frequency Ti current is converted to a high frequency of Kl-1z and is applied to the pair of electrodes 15a and 15b of the rare gas discharge lamp 12. At this time, a required potential is also applied to the auxiliary type 8i16 by the high frequency lighting circuit 11.

As a result, a discharge occurs between the pair of l1i15a and l1i15b, and as shown in FIG.
8 is formed, and this positive column 18 is an auxiliary electrode 16
It is attracted almost evenly over almost the entire length.

Therefore, the phosphor film 14 near the positive column 18 is excited almost uniformly over almost the entire length of the positive column 18, and emits light strongly, increasing its usefulness. Since the light that is emitted almost uniformly over almost the entire length of the bulb 13 is irradiated from the aperture 17, it is possible to obtain an almost uniform illuminance distribution (q) over almost the entire length of the aperture 17.

As a result, according to this embodiment, it is possible to provide a rare gas discharge lamp device suitable as a reading light source that requires uniform illuminance distribution in the axial direction.

In the above embodiment, the high frequency lighting circuit 11 is electrically connected to one end of the auxiliary electrode 16).
The present invention is not limited to this. For example, as shown in FIGS. 4 and 5, one end of the auxiliary electrode 20 may be grounded to create a potential difference between the auxiliary electrode 4 and the positive column 5. This may also provide substantially the same effect as the above embodiment.

(Effects of the Invention) As explained above, in the present invention, almost the entire length of the positive column inside the bulb is spread almost evenly by the auxiliary electrode, and light is irradiated from the aperture, so that light is emitted from the aperture in the axial direction. A nearly uniform illuminance distribution can be obtained.

[Brief explanation of drawings]

FIG. 1 is a wiring diagram showing the overall configuration of an embodiment of the rare gas discharge lamp device according to the present invention, and FIG. 2 shows the rare gas discharge lamp shown in FIG. 1 along the axial direction tA11! Partially cutaway longitudinal cross-sectional view of the case of lIIi? Figure J3 is an end view when the rare gas discharge lamp shown in Figure 1 is cut along the diameter direction, and Figure 4 is a longitudinal section of the rare gas discharge lamp incorporated in another embodiment of the present invention along the axial direction. FIG. 5 is an end view of the rare gas discharge lamp of the embodiment shown in FIG. 4 cut along the radial direction, and FIGS. FIG. 3 is a partially cutaway vertical cross-sectional view of the gas discharge lamp taken longitudinally along the axial direction. 12...Rare gas discharge lamp, 13...Bulb, 14...
- Phosphor film, 15a, 15b... electrode, 16... auxiliary electrode, 17... aperture, 18... positive column. Applicant's agent: Hatano Otsutsu Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7

Claims (1)

[Claims] In a rare gas discharge lamp device having a rare gas discharge lamp in which a phosphor film made of phosphor is coated on the inner surface of the bulb and a gas whose main component is xenon gas is enclosed, the above-mentioned Providing an aperture that lacks a phosphor film,
An auxiliary electrode is attached along the axial direction to the outer surface of the bulb that faces the aperture in the diametrical direction, and substantially the entire length of the positive column inside the bulb is drawn to the auxiliary electrode almost equally. rare gas discharge lamp equipment.