JPS6311796B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser oscillator, and more particularly to a laser oscillator that constantly supplies a glow discharge current to a flash lamp for optically exciting a laser element.

Conventionally, in this type of laser oscillator, in order to prevent a trigger failure of the flash lamp, and furthermore, to prevent malfunction of the laser control circuit etc. due to the high voltage trigger pulse used to trigger the flash lamp, a Constant glow discharge current {This current is called SIMMER current}
A flash lamp excitation method called the Shimmer method is widely used.

As shown in Figure 1, an example of a flash lamp drive circuit using the thinner method includes a high-voltage power supply for charging, a capacitor for a pulse shaping circuit (PFN) for storing laser excitation energy, and an inductance of the same inductance. , a thyristor 3 for controlling the main discharge current from the PFN capacitor 2, a repetitive pulse oscillator 4 for supplying gate pulses to the thyristor 3, a flash lamp 6, and a high voltage for triggering the flash lamp 6. It is composed of a trigger pulse generator 7, a simmer power supply 8 for causing a simmer current to flow through the flash lamp 6, and a resistor 9 for stabilizing the simmer current.

In the conventional simmer-type flash lamp drive circuit as shown in FIG. is applied to keep the flash lamp in a glow discharge state, and then the gate pulse from the repetitive pulse oscillator 4 repeatedly turns on the thyristor 3 to supply the main discharge current from the PFN capacitor 2 to the flash lamp 6. .

However, in the operation of applying a trigger to the flash lamp 6 to cause a simmer current to flow, it is necessary to increase the voltage of the simmer power supply 8 in order to ensure that the simmer current flows through the flash lamp 6. but,
When the voltage of the simmer power supply 8 is increased, the power loss due to the glow discharge stabilizing resistor 9 increases and the laser excitation efficiency deteriorates. Poor laser excitation efficiency has the disadvantage that the power supply becomes large and miniaturization is difficult.

The present invention provides a laser oscillator that eliminates the drawbacks of the conventional example by flowing the main discharge current from the PFN capacitor together with the simmer current at the same time as the trigger pulse of the flash lamp, thereby making it possible to reduce the size and weight of the laser oscillator. be.

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 2 is a partially block circuit diagram showing a flash lamp drive circuit of a laser oscillator according to an embodiment of the present invention. A forming circuit (PFN) capacitor 2 and its inductance 5, a flash lamp 6, a thyristor 3 for controlling the main discharge current from the PFN capacitor 2, and a repetitive pulse oscillator 4 for supplying gate pulses to the thyristor 3. , a high-voltage trigger pulse generator 7 for supplying only one trigger pulse to the flash lamp 6 at the same time as the first pulse of the pulse train obtained from the repetitive pulse oscillator 4, and a simmer current flowing through the flash lamp 6. It is composed of a simmer power supply 8 and a resistor 9 for stabilizing the simmer current.

To explain the operation of this circuit, first, one trigger pulse is supplied from the high-voltage trigger pulse generator 7 to the flash lamp 6 at the same time as the first pulse of the pulse train obtained from the repetitive pulse oscillator 4, and at the same time A gate pulse from a pulse oscillator 4 makes the thyristor 3 conductive. Therefore, the voltage across the flash lamp 6 increases from the simmer power supply voltage value Vs to the charging voltage value Vp of the PFN capacitor 2 (normally Vp>Vs). When the trigger is reliably applied, the main discharge current flows from the PFN capacitor 2 to the flash lamp 6, and the simmer current flows from the simmer power supply 8 through the resistor 9, and the flash lamp enters a glow discharge state. Next, the thyristor 3 is repeatedly turned on by the gate pulse from the repetitive pulse oscillator 4, and the main discharge current is supplied from the PFN capacitor 2 to the flash lamp 6.

As explained above, by configuring the main discharge current to flow from the PFN capacitor 2 together with the simmer current at the same time as the trigger pulse of the flash lamp 6, the simmer power supply voltage can be set lower than in the conventional example, and the simmer current can be reduced. Stabilizing resistor 9
The power loss caused by this is reduced compared to the conventional method, and the laser pumping efficiency can be increased.

As explained above, the present invention sets the simmer power supply voltage lower than the conventional example by configuring the main discharge current from the PFN capacitor to flow together with the simmer current at the same time as the trigger pulse of the flash lamp. This has the effect of reducing the size and weight of the laser oscillator because the laser excitation efficiency can be increased.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a conventional laser oscillator, and FIG. 2 is a circuit diagram showing an embodiment of the present invention. 1...High voltage power supply for charging, 2...Capacitor for pulse shaping circuit, 3...Thyristor, 4...Repetitive pulse oscillator, 5...Inductance, 6...Flash lamp, 7...High voltage trigger pulse generator, 8...Simmer power supply, 9...Resistance.

Claims (1)

[Claims] 1. A switch element that turns on and off the main discharge current flowing through the flash lamp that optically excites the laser element using an output from a pulse oscillator, a pulse oscillator that repeatedly controls on and off the switch element, and an output of the pulse oscillator. a high-voltage trigger pulse generator that supplies only one trigger pulse to the flash lamp at the same time as the first pulse in the pulse train; a power source that is connected to the flash lamp and constantly flows a glow discharge current; A laser oscillator characterized by having a resistor for stabilizing the oscillator.