JPH02112143A - Cylindrical discharge luminous tube - Google Patents

Abstract

PURPOSE:To obtain a cylindrical discharge luminous tube having increased luminous intensity and capable of generating a spectrum which requires high excitation by applying a high voltage between an anode and a cathode in a gas sealed in a slender cylindrical gas-tight container so as to generate a glow discharge. CONSTITUTION:10 torrs of helium gas is filled in a gas-tight container 15 made of cylindrical covar glass tube through an introduction tube, and also a discharge between anode groups 171 to 17n and a cathode 16 is caused from outside by using a high voltage power supply and a current limit resistor. As the result, owing to the condition of a blocking discharge, each of anode electorle groups 171 to 17n becomes cathode dark space region and the negative glow part 18 of a luminous part is concentrated along the periphery of the anode groups 171 to 17n. Also, the tube voltage reaches 1000 to 1500 volts which can not be observed in any normal glow phenomenon. Thus, a cylindrical discharge luminous tube having its luminous intensity greatly increased and capable of generating a spectrun which requires high excitation, also having a uniform intensity and distribution along its longitudinal direction can be obtained.

Description

Detailed Description of the Invention "Field of Industrial Application" The present invention relates to a discharge arc tube used for illumination, analytical light sources, solid-state laser excitation light sources, etc. This invention relates to a cylindrical discharge luminous tube that generates the specific spectrum 1H from the entire circumference.

``Conventional technology'' Traditionally, cylindrical light sources have been used for lighting, such as fluorescent lamps,
Low-pressure mercury lamps are used for analysis, and xenon arc lamps or krypton arc lamps are used for solid-state laser excitation. Each of these light sources has its own advantages, and each light source has established its use.

In a normal glow discharge, as shown in FIG. 4, a flat cathode 1 and an anode 2 are arranged in an airtight container 3 with an interval of about 301 m+, and for example, helium gas is sealed in this airtight container 3. A high voltage is applied between the cathode 1 and anode 2. Then, a discharge starts, exciting the gas atoms and producing light emission. At this time, light-emitting areas and dark areas alternately exist between the cathode 1 and the anode 2. Typical light emitting part,
The dark areas include, from the upper side of the cathode, a cathode dark area 4, a negative glow part (light emitting area) 5, a Faraday dark area 6, a positive column (light emitting area) 7, and an anode dark area 8. At this time, the voltage between cathode 1 and anode 2 (hereinafter referred to as tube voltage) required to maintain the discharge is:
Usually 150-500 volts.

By the way, in order to increase the brightness of a discharge arc tube or generate a spectrum with a high energy level, it is necessary to highly excite gas atoms by using a discharge that increases the discharge current density.

Blocking discharge has been proposed as a method to achieve this.

As an application example of this blocking discharge, the longitudinal sectional front view shown in Fig. 5 and the Fig. 6
As shown in the vertical side view of the figure, inside the cylindrical airtight container 9,
A cylindrical cathode 10 is arranged, and inside the cylindrical cathode 10, a plurality of rod-shaped anodes 1.11 to 11. Place.

At this time, the distance d1 between each anode 11□, 113, between 11□, 113, etc., and the distance d1 between each anode 10 and each anode 11□, 11□
The distance d2 is made smaller than the thickness of the cathode dark part 4 in FIG. 4. In the airtight container 9, for example, 11 torr of helium gas as a buffer gas and 75 mtorr of crib gas as a laser medium are sealed. Cathode 10
When a high voltage is applied between the electrodes and the anodes 111 to 11n and a discharge is started, the distance between the electrodes is narrow and sufficient discharge cannot be achieved.Since the electrodes are confined in a narrow space, ionization becomes difficult and the tube voltage increases. It is forced to reach 1000 to 1500 volts. Further, the negative glow portion 12 is concentrated on the central axis, and by arranging resonator mirrors 13 and 14 at both ends of the airtight container 9, a 469.4 nm laser that does not oscillate in normal glow discharge is emitted from both ends of the airtight container 9. Oscillation is obtained.

"Problems to be Solved by the Invention" In the conventional glow discharge shown in FIG. There were problems such as the inability to generate lines. Furthermore, although the blocking discharge shown in FIGS. 5 and 6 can generate the desired spectral line, there is a problem in that the light cannot be emitted from the entire outer periphery of the airtight container 9 because the light is emitted from both ends of the airtight container 9. there were.

The object of the present invention is to obtain a cylindrical discharge arc tube for generating a spectrum that requires increased emission intensity and high excitation.

"Means for Solving the Problems" The present invention applies a high voltage between an anode and a cathode in a gas sealed in an elongated cylindrical airtight container to generate glow discharge, thereby emitting light in the direction of the outer circumference of the airtight container. In the discharge arc tube, the cathode comprises at least one rod-shaped electrode arranged in the longitudinal direction of the airtight container,
The anode is formed by arranging a plurality of rod-shaped electrodes around the rod-shaped cathode, and the distance between the adjacent anodes and the distance between each anode and the cathode are set to be smaller than the dark length of the cathode of glow discharge. This is what was placed.

"Operation" For example, 10 torr of helium gas is sealed in an airtight container,
Discharge is started between each anode and cathode using an external high voltage power supply and a current limiting resistor. Then, since the distance between adjacent anodes and the distance between each anode and cathode are arranged to be smaller than the cathode dark region of glow discharge, each anode becomes a cathode dark region and the light emitting region of the negative A portion of the chromium is concentrated around the anode and emitted from the entire outer periphery of the cylindrical airtight container.

Further, the tube voltage reaches a value (1000 to 1500 volts) that is not seen in normal glow discharge phenomena.

``Example'' An example of the present invention will be described below with reference to FIGS. 1 and 2.

``-5 is an airtight container made of a transparent cylindrical Kovar glass tube. In the center of this airtight container 15, a cylindrical cathode 1-6 made of Kovar metal is arranged in the longitudinal direction, and the outer periphery of this cathode 16 is A thin rod-shaped anode also made of Kovar metal]7. ~Core n is arranged. Here, between adjacent anodes 171.177, ]72.1-73,
distance d1 between the surfaces of and the anode]7. The distance d2 between ~17n and the surface of the cathode 16 is arranged to be shorter than the cathode dark length t in FIG. 4 of the glow discharge.

Note that the anode group 17.・ is installed with enough space between it and the airtight container 5 to allow for the presence of negative globules 1-8. Further, a cooling device is provided in the cavity 19 of the cathode 16 for circulating a cooling liquid 20 to cool the cathode 16 .

In the configuration as shown in 2 below, for example, 10 Torr of helium gas is sealed from the introduction tube into the airtight container 1-5, and the anode group 17 is connected to the anode group 17 from the outside using a high voltage power source and a current limiting resistor (both not shown). □~] -7o and the cathode 16 start discharging. Then, depending on the blocking discharge conditions, each anode group 17
, ~core, 1 is a cathode dark region, and the negative glow part 18, which is a light emitting part, is concentrated around the anode groups 171 to 17n. Further, the tube voltage takes on a value (1000 to 1500 pol 1-) that is not seen in normal glow phenomena.

Note that the inter-electrode distances d1 and d are regulated by the length of the cathode dark length of the glow discharge, and this distance is also determined by the gas pressure and current density. Specifically, dl and d2 are 0.
5~1.01ffll, gas pressure is 1~201~l, current density is 1~0~30 mA/cyK.

In the embodiment described above, a large number of rod-shaped electrodes were used as the anode groups 17□ to ]71, but the present invention is not limited to this, and a mesh-shaped cylindrical anode 17. as shown in FIG. 3 was used. You can also use In this case, in order to satisfy the conditions for blocking discharge, the size d3 of the mesh holes 21 is formed to be smaller than the cathode dark length t of the glow discharge.

In the above embodiments, the airtight container has an elongated cylindrical shape, but it is not limited to this, and may have a cylindrical shape such as an elliptical cylinder, a polygonal cylinder, or a semi-cylindrical cylinder.

"Effects of the Invention" Since the present invention is configured as described above, the present invention has a larger [1.
It has excellent effects such as being able to increase the brightness to a maximum of 30%, being able to generate a spectrum that requires high excitation, and being able to obtain uniform intensity and distribution over the longitudinal direction.

[Brief explanation of the drawing]

FIG. 1 is a sectional view taken along line A, -A showing one embodiment of the cylindrical discharge luminous tube according to the present invention, FIG. 2 is a sectional view taken along line B-1'3 of the same as above, and FIG. 3 is another embodiment of the present invention. A partial perspective view showing an example, FIG. 4 is a sectional view of a conventional glow discharge tube, FIG. 5 is a sectional view taken along the line 0-C of a conventional blocking discharge tube, and FIG. It is. 1 cathode, 2 anode, 3 airtight container, 4 cathode dark area, 5
Negative gloss part, 6. Faraday dark part, 7 positive column, 8.
Anode dark part, 9...Airtight container, 10. Cathode, ]-11~1
1n... Anode, 12... Negative glow part, 13, ]-4.
Resonator mirror,] 5. Airtight container, 16. Cathode, 178-17
n Anode, 18... Negative glow part, 19 Cavity, 20
・Cooling liquid, 21 holes.

Claims (3)

[Claims] (1) In a discharge luminous tube in which a high voltage is applied between an anode and a cathode in a gas sealed in an elongated cylindrical airtight container to generate glow discharge, thereby emitting light in the direction of the outer periphery of the airtight container. , the cathode consists of at least one rod-shaped electrode arranged in the longitudinal direction of the airtight container; the anode consists of a plurality of rod-shaped electrodes arranged around the rod-shaped cathode; A cylindrical discharge arc tube characterized in that the distance and the distance between each anode and cathode are arranged so as to be smaller than the cathode dark length of a glow discharge. (2) In a discharge luminous tube in which a glow discharge is generated by applying a high voltage between an anode and a cathode in a gas sealed in an elongated cylindrical airtight container, thereby emitting light in the direction of the outer periphery of the airtight container. , the cathode consists of at least one rod-shaped electrode arranged in the longitudinal direction of the airtight container, the anode consists of a mesh electrode arranged around the rod-shaped cathode, and the diameter of the hole of the mesh anode and each The distance between the anode and the cathode is
A cylindrical discharge luminous tube characterized in that the tube is arranged so as to be smaller than a cathode dark section of a glow discharge. (3) The cylindrical discharge arc tube according to claim 1 or 2, wherein the cathode is hollow and a cooling liquid is circulated inside.