JPS637035B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser device, and particularly to a laser device that senses the oscillation wavelength of a laser device having a plurality of oscillation wavelengths and switches the sensitivity of a laser output monitor circuit.

Argon lasers are generally known as laser devices having multiple oscillation wavelengths. In order to change the oscillation wavelength of this argon laser, a prism is inserted between the mirrors constituting the oscillator to separate the light and amplify only the light of the desired wavelength to be oscillated. In general, a laser such as an argon laser can change the laser output by changing the current flowing through the laser tube, that is, the discharge current. In order to monitor and control this laser output, it has been detected using an optical element (generally a solar cell). In such a configuration, the wavelength sensitivity of the optical element is not flat over the entire oscillation wavelength, so the output of the laser output monitor circuit varies depending on the oscillation wavelength, and the optical feedback signal used to control the optical output varies depending on the oscillation wavelength. There were flaws that changed. For this reason, conventional laser output monitor meters have had scales that have been changed depending on the oscillation wavelength, or have been equipped with a changeover switch.

An object of the present invention is to improve such drawbacks and to provide a laser device having an oscillation wavelength sensing circuit that allows a laser output monitor meter to use the same scale over the entire oscillation wavelength range and that makes the output of the laser output control circuit the same. be.

According to the present invention, there is provided a laser tube having a plurality of oscillation wavelengths, an oscillator having a mechanism for changing the oscillation wavelength, a power source for supplying voltage to the oscillator, and a photodetector for receiving part of the laser output light. The vessel and
In a laser device having a laser output monitor circuit that receives the output of the photodetector and monitors and controls the laser output, an oscillation wavelength sensing circuit equipped with a semiconductor color sensor consisting of two photodiodes with different spectral sensitivity characteristics is provided, and the oscillation A laser device is obtained in which the output of the wavelength sensing circuit is input to a laser output monitor circuit that monitors and controls the oscillation output of an oscillator, and the sensitivity of the laser output monitor circuit is switched.

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

In the figure, light output from a laser tube 1 passes through a mirror 2, a beam splitter 3, and enters a semiconductor color sensor 4 and a solar cell 5. Here, the laser light incident on the semiconductor color sensor 4 is converted into a voltage by the semiconductor color sensor 4 and input into the oscillation wavelength sensing circuit 6. On the other hand, the output of the solar cell 5 is amplified by an amplifier 7 and output to a laser output monitor meter 11 and a discharge flow control circuit 10 that controls the discharge flow of the laser tube 1.

In such a configuration, the semiconductor color sensor 4 that receives the laser light from the beam splitter 3
Photodiodes 2 each with different spectral sensitivity characteristics
The output voltage of each photodiode is logarithmically compressed and subtracted by an oscillation wavelength sensing circuit 6,
The level of the output is judged and the oscillation wavelength of the laser is detected. By performing logarithmic compression and subtraction operations on the output of the photodiode in the oscillation wavelength sensing circuit 6, it is possible to output an output corresponding to the wavelength of the light to the level judgment circuit without being affected by the intensity of the incident light. . Then, this level judgment circuit judges the voltage of each wavelength, and the amplifier 7 of the solar cell 5
The switch 8 changes the amplification factor. On the other hand, the amplification factor of the amplifier 7 is changed by changing the value of the feedback resistor 9, and this is done by the switch 8.

With the above configuration, even if the oscillation wavelength is different, the output of the amplifier 7 changes only depending on the strength of the light, so the laser output monitor meter 11 only needs to be marked with one scale, and the discharge current can be controlled. The output to the circuit 10 is also controlled only by the intensity of the light.

[Brief explanation of the drawing]

The figure is a circuit diagram showing the configuration of a laser device according to an embodiment of the present invention. 1... Laser tube, 2... Mirror, 3... Beam splitter, 4... Semiconductor color sensor, 5...
... Solar cell, 6 ... Oscillation wavelength sensing circuit, 7 ... Amplifier, 8 ... Switch, 9 ... Resistor, 10 ... Discharge current control circuit, 11 ... Laser output monitor meter, 12 ... Power supply, 13 ... ...Laser output monitor circuit.

Claims (1)

[Claims] 1. A laser tube capable of oscillating multiple wavelengths, an oscillator with a mechanism to change the oscillation wavelength, a power supply that supplies voltage to this oscillator, a photodetector that receives a portion of the laser output light, and this photodetector In a laser device having a laser output monitor circuit that monitors and controls the laser output by receiving the output of A laser device characterized in that the sensitivity of the laser output monitor circuit is switched according to the output of the laser output monitor circuit.