JPS60151953A - Trigger probe for flash discharge lamp - Google Patents

Abstract

PURPOSE:To prevent the fluctuation of an arc discharge path and stabilize its discharge by forming a trigger probe to control the discharge of a flash discharge lamp with a high melting point metal and by covering the other parts of it with an insulating layer with the exception of an exposed tip. CONSTITUTION:A bulb-shaped flash lamp used as the light source of a spectroscope, etc., is formed as follows: In a glass enclosure 1, a positive electrode 2 and a negative electrode 3, which are made of a calcined mixture of alkaline earth oxide and high melting point metal powders such as W, etc., are arranged to oppose to each other, and plural trigger probes 4 are set to control discharge. Also the trigger probe 4 is coated with an alumina coating 53, leaving the tip 52 of a tungsten wire 51 uncoated; and the tip 52 is positioned near the electrodes 2, 3. In this way, since the tip 52 only contributes to control the discharge, the fluctuation of an arc discharge path can be controlled and the discharge can be stabilized.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field) The present invention relates to a trigger probe for a flash discharge tube that starts discharge for a flash discharge tube used in a spectrometer or the like.

(Background of the invention) Figure 1 shows a conventional fludge J with a trigger probe.

1 is a schematic diagram showing an example of a discharge tube.

In a conventional flash discharge tube of this type, a sintered electrode having a shape as shown in FIGS. 2(a) and 2(b) is used as a cathode and anode.

This sintered electrode is made by mixing alkaline earth oxide as an electron-emissive material with high melting point metal powder such as W, Mo, Ni, etc., press-forming it into a cylindrical or prismatic shape as shown in the figure, and then press-forming it in a vacuum. It is sintered at a medium temperature.

As shown in FIG. 1, these electrodes are arranged facing each other as a cathode 4fA2 and an anode 3.

Between the cathode 2 and anode 3, there is a
Approximately 1 to 5 trigger probes 4 are arranged depending on the distance between the electrodes.

The trigger probe 4 has a cathode 2. This is an electrode that starts a discharge between the anodes 3.

FIG. 3 is an enlarged view of a conventionally used trigger probe. These trigger probes can handle the high temperature of the arc, usually 0.2~0.5
A high melting point metal such as tungsten with a diameter of about 10 mm is used.

In order to operate the flash discharge tube, a DC voltage of 100 OV is applied between the cathode 2 and the anode 3.

Approximately 4000 V to trigger 1:1-4 (width 50 points)
When a Nollus voltage of 5 ec) is applied, a discharge occurs between the cathode 2 and the anode 3, and light is emitted.

The discharge between the anode 3 and the cathode 2 is caused by the voltage of the trigger probe 4.
When 1: is removed, it disappears in about 5 μsec.

Further, a luminous gas of approximately 11) O) is inserted into the bulb.

In order to stabilize the light output of this type of discharge tube, the arc discharge point must be fixed at one point on the electrode and not move during each flash, and the arc O) discharge diameter!
It is necessary to ensure that -δ is constant and does not fluctuate.

The present inventors have studied the cause of the instability of the discharge in order to stabilize the discharge point.

As a result, discharge instability is caused by fluctuations in the arc discharge path (
We discovered that the cause of this phenomenon is due to the phenomenon known as "snaking".

Also, the cause of fluctuations in the arc discharge path is +-regap l:I-
We found that this is due to the fluctuation of the discharge position on the disk.

°With a conventional trigger probe, as shown in Figure 4,
The light output was unstable because the discharge path was bent or the flash moved. In the figure, 41 is the normal path, and 42 is the discharge i\ when snaking occurs.
Show the path.

(Object of the Invention) An object of the present invention is to provide a trigger probe for a flash discharge tube that can eliminate the instability of the luminous flux caused by fluctuations in the arc discharge path.

(Structure of the Invention) In order to achieve the above object, the trigger probe for a flash discharge tube according to the present invention is a trigger probe for a flash discharge tube which has a cathode and an anode arranged to face each other and has a discharge control function. , 11; 1 A Riga probe is formed of I-melting point metal, with the tip portion exposed and the other portions covered with an insulating layer.

According to the above configuration, it is possible to prevent the above-mentioned snaking.

(Description of Examples) The present invention will be described in more detail below with reference to the drawings and the like.

5th III Let: It is a figure which shows the 1st Example of the trigger probe for flash discharge tubes by this invention.

The flash discharge tube trigger probe 51 of this embodiment has a straight i\Q, 3 rn rn tungsten wire 52 with the tip:: 1 part 't',, (] n opening [Q, leaving 1).
2m ITI thickness alumina τl-fooing 53
It has been subjected to

The configuration and operation of a flash discharge device using this trigger 1:1-b 51 will be explained.

The cylindrical electrodes shown in Fig. 2(a) were used as cathodes and anodes in a glass tube with an outer diameter of 28 mm and a length of 30 mm as shown in Fig. 1, and the distance between the two electrodes was 3.0 rom. and place it.

The two tips of the trigger probe 51 are arranged at equal intervals between the anode and the cathode.

A flash discharge tube containing approximately 6001 l of xenon gas was installed in a glass bulb.

A DC voltage of 1000 V is applied between both electrodes of the flash discharge tube.
A lighting test was conducted at a lighting frequency of 100 Hz and an input energy of 0.1 Joule per pulse.

In this example, extremely stable characteristics with a luminous flux stability S of 0.6 to 1.2% were obtained over a lifetime of 109 pulses.

Note that the luminous flux stability S is defined as the fluctuation of the light intensity that passes through Surin 1 by projecting an arc and inserting a 1-inch slit in the center of the arc projection image ((In+ax-ITnin)/Im+Ix) xlo
o (%).

Here, I max is the maximum light intensity, and lm1n is the minimum light intensity.

When the luminous flux stability S is said to be low, it means that there is little movement in the shape or position of the discharge.

The conventional flash discharge tube shown in Fig. 1 and the trigger probe 4 (not shown in Fig. 3) were arranged in the same positional relationship as above and were operated under the same conditions. The luminous flux stability S at this time was about 6 to 10%.

Therefore, by making the trigger probe 4 have the structure shown in FIG.
-It will be a disaster.

Figure 6 shows flash discharge tube 1 to regub 1 according to the present invention.
: It is a figure which shows the 2nd Example of J-zo.

Flood 1 discharge in this example! The i'JI I-Riga probe 61 has a tungsten wire 62 with a diameter of 0.3 m rn with a 2.0 m rn distal end portion shaped like a conical needle, and this portion is exposed. It is coated with alumina coating 63 in thickness.

The same test as above was conducted by replacing the trigger probe 61 with the trigger probe 51.

In the second embodiment, 'C' over a lifetime of 109 pulses.
Extremely stable characteristics with a luminous flux stability S of 0.4 to 0.8% were obtained.

The reason why the characteristics of the second embodiment are more stable than those of the first embodiment is because the electric field is more concentrated at the tip of the trigger probe 61 than in the 1-trigger probe 51.

(Modifications) Various modifications can be made to the embodiments described in detail above within the scope of the present invention.

In each of the above embodiments, the trigger probe was coated with alumina coating, but since it is sufficient to cover this portion with an insulator, the same effect can be obtained by covering the trigger probe with a pipe-shaped insulator such as an alumina tube.

Further, although tungsten is shown as the metal material 1'l of the trigger probe, other high melting point metals can be used as well.

(Description of Effects) As explained above, in the trigger probe for a flash discharge tube according to the present invention, except for the tip of the high-melting point metal facing the discharge path, the rest is covered with an insulating film.

The tip of the trigger probe is used to control the discharge.)
Since it is only the 7i part, if it is shaped like this, the arc will be fixed, snaking can be suppressed, and stable discharge will be 1!
78°

[Brief explanation of the drawing]

Figure 1 is a schematic diagram showing an example of a flash discharge using a conventional trigger.
)'s Δ−ΔIvi diagram ゛ζA side. FIG. 2 is a perspective view showing the shape of the sintered electrode. FIG. 3 is an enlarged view showing the trigger probe for flash release market 1 of the secondary model. FIG. 4 is an enlarged view of the conventional fludge j and discharge 1:i without showing snaking. Figure 5 shows the flash discharge tube trigger according to the present invention!
- FIG. First, FIG. 1 is an enlarged view showing a second embodiment of a flash discharge tube 1"-zo according to the present invention. 1...Glass volume Xj1 2...Cathode 3...Anode 4...Trigger probe 5...Stem introduction bottle 21...Sintered part 22...Introduction wire 41...Normal discharge Path 42... Snaking discharge path 51... Trigger probe 52... Tungsten wire 53... Alumina coating 6I... Trigger probe 62... Tungsten wire 63... Alumina coating patent applicant Hamamatsu Bo 1 Nix Co., Ltd. Agent Patent Attorney Ino 1-1 Jusai 1 Figure 2 Figure 3 Figure 4 Figure 75 Figure 6

Claims (1)

[Claims] (1,1 Trigger knob 1 for a flash discharge tube that controls discharge of a flash discharge tube in which a cathode and an anode are arranged facing each other)
- A trigger probe for a flash discharge tube, characterized in that the trigger probe is made of a high melting point metal, with a tip portion exposed and the other portion covered with an insulating layer. (2) The tip Midt portion of the trigger probe is cylindrical.1. j-bu. (:3) The 111th part of the trigger bar 1-1-b is a circle M
The 1-regap 1-knob for a Furanoche discharge tube according to claim 1, which has a T-shape.