JPS582087A - Gas laser tube device - Google Patents

Abstract

PURPOSE:To contrive to improve the starting characteristic and to form a gas laser tube device in a small type by a method wherein an energizing DC voltage is applied between the anode and cathode of a laser tube from a DC electric power source circuit, and starting discharge path is formed in the laser tube by a starting voltage generating circuit. CONSTITUTION:The main discharge path between the anode 17 and the cathode 19 is formed in the gas laser tube 10 by a capillary tube provided in the tube 10, the cylindrical cold cathode body is provided in the coaxial type around the capillary tube, and end tubes 19 having mirrors respectively are protruded on the outsides of both the ends of a vacuum vessel. The DC electric power source circuit 11 applies the energizing DC voltage between the anode 17 and the cathode 19 of the tube 10. One side of output of the starting voltage generating circuit 21 is connected to the anode 17 or to the cathode 19, and the other electrode thereof is connected to an electrode 20 for starting discharge provided being close to the outside of the tube 19 as to form a starting discharge path through the main discharge path consisting of the capillary tube.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas laser tube device, and more particularly to a power supply device with improved discharge initiation characteristics, ie, starting characteristics, of an internal mirror coaxial gas laser tube.

For example, gas laser tubes using argon, helium neon, etc. require approximately 3 k to initiate a steady discharge.
It is activated by applying a high voltage several times the steady discharge voltage of V. This generated W3 voltage is a pulse wave or a high frequency wave, and conventionally, it has generally been applied to the anode of the Ray+F tube without being superimposed on the steady discharge voltage. In such a laser tube oscillator, although the start-up time at time A is relatively 11, the circuit elements of the anode circuit and the entire wiring are
Make sure that the GJ has enough resistance to the excitation voltage of several kV.
Must be. In addition, if a configuration is adopted in which the secondary winding of the step-up transformer is inserted in the anode circuit, this secondary winding must be thick enough to safely flow the starting discharge current and the steady discharge current. , this transformer becomes a doll. As described above, the conventional laser tube apparatus of this type has disadvantages in that the apparatus is large in size and circuit elements having high withstand voltage characteristics must be used in the anode circuit.

On the other hand, in the external mirror side arm type gas/laser tube, a starting discharge electrode is wound around the outer circumference of the xibira reach 1-pipe.
A structure in which a starting voltage is applied between this electrode and the cathode has also been proposed. However, this cannot be directly applied to an internal mirror coaxial gas laser tube due to the difference in the arrangement of the electrodes in the laser tube. It is desired to develop an electrode arrangement and circuit configuration with the best starting characteristics for an internal mirror coaxial laser tube.

The present invention has been made in view of all the circumstances as described above.
It is an object of the present invention to provide a Kass laser tube oscillation device that uses an internal mirror coaxial gas laser tube, has good starting characteristics, and can be miniaturized.

Embodiment A will be described below with reference to the drawings.

<j The same parts have the same symbols.

Shown in Figures 1 to 4? The circuit configuration of the device is as shown in Figure 1. That is, a DC power source (11) that generates a steady discharge voltage of the laser tube (10) and a laser If tube section (12) are connected by two couples (13). The DC power supply (11) has a power transformer (14,) whose negative winding is connected to a commercial power supply, a 1B voltage rectifier circuit (15) connected to the secondary winding, and a constant current circuit (16). ing. The variable resistor <Vt<> is for adjusting the constant current value. For example, a 4kV DC type port obtained with a single-current power supply (11) is connected to two H-pulls (13).
A voltage is applied between the anode <17> and the cathode (18) of the laser tube. Note that the anode (17) is equipped with a ballast resistor ([<1)
The IIJ current voltage voltage poles are connected via.

Now, one side of the Lehri tube (10) is the J dotchicove (1).
A J-ring-shaped starting discharge electrode (20) is wound around the outer periphery of the electrode 9). And this electrode [1 (20) and cathode (18)
A high frequency high voltage generated by a starting voltage generation circuit (21) is applied between the two. This circuit (21
) is driven by a voltage obtained by branching from before the ballast resistor (R1) leading to the anode (17) through each leader resistor (R2), (R3), and (R4). The bleeder resistor (R2) and (R3) are connected to the trigger capacitor (CI), and the resistor (R4) is connected to the time constant content 1 node (C2).
) are connected to each other. Also, the resistance (R2), (R
3) The -order winding of a pulse transformer (P T ) is connected between them via a silicon controlled rectifier (SCR). A resistor (R3), an electric element (DZ) like a neon tube, and a gate current adjustment resistor (R5) are connected between the cathode and gate of the SCR.
A gate protection resistance (R7,
20).

The cathode (18) circuit is a gate current adjustment resistor (1<6)
Connect to the negative side of the DC power supply to the end of the next winding of the pulse transformer (PT) and to the negative side of the DC power supply through the discharge current detection resistor (R8). has been done. The negative and secondary winding ratio of the pulse transformer (one unit) is approximately l:HlO.

Next, an example of the structure of a device incorporating this circuit element will be explained with reference to FIGS. 2 to 4. This device is a DC power supply circuit (1
1) is stored in the power supply box (11a), and the Sea 11 tube (
10), a starting voltage generation circuit (21), and a ballast resistor (R1) are assembled together in a Ray F tube storage box (22), and these are connected by two wobbles (13).

The arrow (1) indicates the laser light output.

Laser tube (,10) 1. L, glass cylindrical container
23), each with a small diameter entrench 1-tube (1
9) 1, 24) ka, connection. . , Wow. edge.

End plate (27) with mirrors (25>, (26))
, (28) are hermetically sealed. A capillary tube (29) is arranged on the tube axis t inside the container (23), and is supported by a holder (30) at one end of the outer periphery. A cylindrical cold cathode body (31) is coaxially provided on the outside of the capillary tube (29), and is connected to a negative pole (18) passing through a stem (33). An anode lead (17) passing through the stem (33) is exposed in the space inside the holding cylinder (3o). Inside the end tube (24) toward the total reflection mirror (26),
A tubule (35) with a meta-window (34) is connected to the stem (
32) is extended from the inside. In such an internal mirror coaxial laser tube, a discharge gas such as argon, helium, or neon is sealed inside the tube, and the main discharge path is an anode lead (
17), passes through the pores of the capillary tube (29), and forms a path to reach the cold cathode body (31). Note that the holding cylinder (
3o) substantially separates the space between the anode and the cathode.

Now, on the outer peripheral wall of the end tube (19) that directly communicates with the anode lead (17), a thin conductive plate is rolled up.
A rolling J discharge electrode (20) is wound. This electrode is covered with an insulating cover (36) for external discharge protection 11. And the box (22) in which the laser tube (10) is stored, the sea 1f tube J dochi, -L-pu <19)
Each circuit element of the starting voltage generation circuit (21) and the ballast resistor are attached to the plate-shaped printed wiring boards (37) and (38) in the hole, and held by the cylindrical holder (39). Fixed. This holder (39)
is fixed to the removable cap (22a) of the box (22) by fitting into the numbered protrusion tube (22b).

Note that the main 11 knob (22a) is provided with an output window (22C) through which the output laser beam passes. Also, J Dodubu〈1
9) There is a perforated protective cover (
40) is covered.

The holder (39) is held with one end fitted into the protruding tube (22b) and the other end fitted into the protective cover (40).

The circuit element is particularly a discharge element (DZ) consisting of a neon tube.
) is placed at a position such that a part of the discharge light emitted from the cold cathode body (31) reaches the interior of the laser @<10), particularly preferably the electron emitting surface of the cold cathode body (31). Also, pulse transformer (
PT) is placed close to the starting discharge electrode (20), so as to have a short wiring.

Next, the operation of this laser tube device will be explained.

When the DC power supply is operated, a voltage of approximately 4 kV is applied between the anode and cathode of the laser tube. At the same time, a bleeder resistor (R2) is connected to a starting voltage generating circuit (21) branched from this power supply.
), capacitor (C1), ( via IJ and (R3)
C2) respectively. Since the internal resistance between the anode and gate of SCH is relatively small, a voltage approximately corresponding to the charging voltage of the capacitor (C2) is applied to the discharge element <DZ), and when the discharge starting voltage of this discharge element is exceeded, the discharge current increases. flows to the gate and turns on the SCR. Then, the charge charged in the capacitor (C1) flows through the SCR and the second winding of the pulse transformer (Pl). This induces a pulsed high voltage on the secondary side of the pulse transformer (PT), which is applied between the cathode of the laser tube and the starting emitter electrode. This operation is such that for the current discharged through the mold cylinder 5C) of the cylinder I, the shunt current value through the resistor fA (R2>) is S C1
＜To make it so small that it cannot sustain the glue-on (R
2) is set, and the current passing from the gate to the anode becomes approximately zero, thereby turning off the SOR. As a result, the capacitor (cl),
The charging of (C2) is tifl, and the above (7) S CR
17) Turn-on begins. This period is determined by each bleeder resistor (R2), (l(3), (R4), capacitor (C
1), <02), release tjll-(DZ>(7) MlK start voltage, etc. These values are determined by turning on scR,
off, and the frequency of the secondary side alternating output voltage j (of the pulse transformer (P"1') is determined to be 100 to 100011z1, preferably 30Q to eoot+l. This causes a starting discharge to the 118 poles of the laser tube. Electrode (2
0), a positive 'R frequency high electric current t[ of approximately 10 to 15 kV (sensitivity value) is applied. Due to such high frequency and high voltage, a high frequency glow discharge is generated in the laser tube, which passes through the glass wall of the end tube (19), passes through the capillary tube (29), and reaches the cold cathode body. The gas sealed in the laser tube is excited by this starting discharge, and the cold cathode body is also photoexcited by a slight amount of light emitted by this starting discharge, facilitating electron emission. This causes a main discharge between the anode and cathode of the laser tube. When the main discharge occurs, a current of several IA flows due to the main discharge, that is, the steady discharge. In other words, this current is shunted to the circuit of the resistor (R6) due to the potential difference generated at the detection resistor (R8).

Since the current flowing through the resistor (R6) flows from the gate 1- of the SCR to the anode, the SCR is turned on regardless of the operation of the discharge element (DZ). This allows the capacitor (
The voltage across C1) remains approximately zero, the generation of alternating voltage by the SCR stops, and the pulse transformer (PT)
The secondary side output of will also be zero. That is, the generation of the starting voltage automatically stops at the same time as the main discharge of the laser tube starts. Therefore, the high frequency type LIL is not marked on the starting discharge electrode (20).

With this configuration, the starting discharge current flowing through the secondary winding of the pulse transformer is on the order of μ△, and the winding is Jrf II
Vine using Shino II. For this reason, the pulse knee lance can be made extremely small and can be installed together with each element of the activation type mouth generation circuit on the outer periphery of the laser tube storage box. Furthermore, by arranging a starting discharge electrode on the outer periphery of the conductor 1 that communicates directly with the anode, and applying a starting voltage between this electrode and the cold cathode body, the entire main discharge path of the laser tube can be It has very good starting characteristics because it can reduce the starting discharge that passes by 11".Especially if you apply a starting bar so that the starting discharge electrode is always positive with respect to the cold cathode body as in the previous wiring. It was found that the startup was extremely stable.Actual measurements by the inventors showed that G
It was confirmed that it was possible to start up to two discharges in less than 0.5 seconds. Furthermore, this high frequency starting F#i
It was also confirmed that in the case of a helium-neon gas laser tube, lf causes a very stable starting discharge within the above-mentioned frequency range.

In addition, since the starting voltage generating circuit element is installed close to the starting discharge electrode, the high frequency high voltage circuit 1k can be shortened, and waveform distortion can be avoided (this also makes it possible to start efficiently). Since the ballast resistor is also connected close to the anode of the laser tube, it is advantageous because it can reduce the amount of stray capacitance between the lines due to cables, etc. Also, the cable connecting the DC power supply and the laser tube storage box is 3. ~4
Since the cable can withstand kV, it is safe, easy to operate, and economical.

Note that it is simple to use a discharge light emitting element such as a neon tube as the discharge element (DZ), and it is also placed at a position within the laser tube where the discharge light can reach the main surface of the cold cathode body, as described above. As a result, the cold cathode body is excited by the emitted light, and the starting characteristics are further improved. In this regard, since the laser tube is usually installed in a storage box with a dark interior, if it is left in a non-operating state in this dark place for a certain period of time, it will be difficult for the cold cathode body to conduct electricity. However, according to the present invention, the cold cathode body is immediately photoexcited by the glow caused by the starting discharge or by the light emitted from the neon tube, resulting in good starting characteristics. can get.

In addition to neon tubes, discharge elements include DIAC and TEL-DAI A.
You can also use ``-do''. Also, other ib can be used instead of SCH.
Uses a current control element with control electrodes. The present invention can also be applied to a method in which the anode of the laser tube is set to ground potential and a high voltage is applied to the cathode for operation. In such a case (one pole of the secondary side of the pulse transformer is connected to the anode at a ground potential, and the other pole is connected to the cold cathode body. It can be used by connecting them together.This causes a starting discharge to occur between the anode and the starting tli electrode.In addition, the starting electric power generator-1 circuit cable, which is installed inside the laser tube storage box, is integrated with the printed circuit board using insulating resin. The device may be attached by molding.This further improves the withstand voltage characteristics and allows the elements to be placed closely together, which is more advantageous for downsizing the device.

As described above, according to the present invention, it is possible to obtain a Lehner tube device that can be made smaller and has good starting characteristics.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram showing an embodiment of the present invention, FIG. 2 is a schematic diagram showing an example of its application, FIG. 3 is a sectional view of the shark part thereof, and FIG. 4 is a perspective view of the main part thereof. (10)...Laser tube, (11)...DC power supply, (13...Cable, (21)...Starting voltage generation circuit, (19), (24)...End tube, ( 29)...Capillary duplex, (17
)... Anode, (18)... Cathode, (20) ・
... Starting discharge electrode, (D7) ... Discharge element, (P
T)...Pulse transformer, <22)...Box.

Claims (7)

[Claims] (1) A capillary tube installed inside the tube forms the main discharge path between the anode and the cathode, and a cylindrical cold cathode body is installed coaxially around the tube. A gas Rayleigh tube consisting of a 2R dot 1-1 with mirrors protruding from both ends, a DC power supply circuit for applying an energizing DC voltage between the anode and cathode of the laser tube, and a discharge starting height. A starting voltage 1f generating circuit that generates a voltage is provided, one pole of the output horn of this starting voltage generating circuit is connected to the anode or cathode of the laser tube, and the other pole is connected to the anode or cathode of the laser tube.
A gas laser tube characterized in that it is connected to a starting position electrode provided close to the outside of a J dub such that a starting discharge path is formed via a main discharge path formed by a V-pilary tube. Device. (2) Starting voltage generation circuit is 100 to 100011
2. A gas laser tube device according to claim 1, comprising a high frequency generating circuit for generating an alternating voltage of z and a voltage circuit for generating the alternating voltage by a pulse transformer. (3) The high frequency generation circuit has a current control element with a control electrode, and! III III Resistor, capacitor on Ii pole,
The gas laser tube device according to claim 1 or 2, which is driven by applying a charging/discharging voltage by a discharge element. (4) The gas according to claim 1, comprising: a circuit that detects the discharge current caused by the main discharge between the anode and cathode of the laser tube and automatically stops the alternating voltage generation of the starting voltage generation circuit; Laser tube equipment. (5) A part of the main discharge current flowing between the anode and cathode of the laser tube is applied to the control lIl electrode of the current control element to stop the alternating voltage generation of the high frequency generation circuit (claim 2) , the gas laser tube device according to item 3 or item 4. (6) The cass laser tube device according to claim 3, wherein the discharge element is a neon tube. (7) The gas laser tube device according to claim 6, which is provided in a position where a discharge light emitted by neon light can reach the inside of the laser tube.