JPH1144579A - Device of detecting laser light - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent an excessive incident light from being emitted outside and to prevent breakdown of a detector due to an excessive laser light, unstableness due to a change in temperature and long-time deterioration of detection sensitivity, in a laser light detecting device which detects a laser light emitted from a laser oscillating device. SOLUTION: A limit switch 7 is provided for a beam splitter 2 of a laser light detecting device, while a screen plate 9 fitted with a limit switch 10 is provided in front of a detector 4, and a laser oscillating device 1 is controlled by a signal from each of the limit switches 7 and 10. Outward emission of an excessive incident light due to removal of the beam splitter 2 is prevented and, besides, breakdown of the detector 4 due to a laser light 13 is prevented. Moreover, a temperature control of the detector 4 is made by a temperature- controlled medium 12.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser light detecting device for detecting a laser light emitted from a laser oscillation device, and to prevent an excessively incident light from being emitted to the outside. To prevent breakage, prevent instability due to temperature change, and prevent a long-term decrease in detection sensitivity.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a configuration of a conventional laser light detecting device. In FIG. 4, 1 is a laser oscillation device, 2 is a beam splitter, 3 is a condenser lens, 4 is a detector, 5 is an amplifier, and 6 is an output terminal.

A laser beam 13 generated by the laser oscillation device 1 having this configuration is split by a beam splitter 2, and one of the laser beams is condensed by a condenser lens 3 and detected by a detector 4. The signal from the detector 4 is amplified by the amplifier 5 and output from the output terminal 6. The other laser beam is applied to the work 14 via a processing system or the like,
Perform processing.

[0004]

However, in the above-described conventional configuration, when the beam splitter 2 is removed at the time of laser adjustment or the like and processing is performed in a state where the beam splitter 2 is removed, an excessive input is irradiated on the work 14 to cause a processing failure. Occur.

In addition, the detector is damaged when the laser light is generated at the time of adjusting the laser or by mistake due to the laser beam exceeding the maximum input of the detector 4.

[0006] Further, the detected light waveform is not stable due to a temperature rise due to the laser beam incident on the detector and a fluctuation due to the outside air temperature. When used for a long period of time, there is a problem that the detection sensitivity is reduced due to dirt or the like.

An object of the present invention is to solve the above conventional problems.

[0008]

In order to achieve the above object, a first means of the present invention is to provide a beam splitter for splitting a pulsed laser beam taken out of a laser oscillation device, and a split pulse beam. A condensing lens for condensing the laser light having a shape, a detector for detecting the split pulsed laser light, an amplifier for amplifying a signal from the detector, and outputting the amplified signal. A beam splitter having a limit switch, an ON signal from the limit switch when the beam splitter is attached, and the limit switch when the beam splitter is removed. Outputs an OFF signal. Thus, it is possible to prevent the excessive laser light from being emitted to the work due to the removal of the beam splitter.

The second means of the present invention comprises a beam splitter for dispersing the pulsed laser light extracted from the laser oscillation device, and a condensing lens for condensing the dispersed pulsed laser light. A detector for detecting a split pulsed laser beam, an amplifier for amplifying a signal from the detector, and an output terminal for outputting the amplified signal. A shield plate provided with a limit switch in front of the detector,
An ON signal is output from the limit switch when the shield plate is open in front of the detector, and an OFF signal is output from the limit switch when the shield plate is closed. Thus, excessive laser light is incident on the detector, and damage to the detector can be prevented.

A third means of the present invention is a beam splitter for dispersing the pulsed laser light extracted from the laser oscillation device, and a condensing lens for condensing the dispersed pulsed laser light. A detector for detecting a split pulsed laser beam, an amplifier for amplifying a signal from the detector, and an output terminal for outputting the amplified signal. Then, the temperature of the detector is controlled by a medium whose temperature is controlled. As a result, it is possible to reduce the temperature rise due to the incident laser light and the fluctuation of the laser light due to the outside temperature.

A fourth means of the present invention comprises a beam splitter for dispersing the pulsed laser light taken out of the laser oscillation device, and a condensing lens for condensing the dispersed pulsed laser light. A detector for detecting a split pulsed laser beam, an amplifier for amplifying a signal from the detector, and an output terminal for outputting the amplified signal. Then, the beam splitter, the condenser lens and the detector for detecting the laser beam are installed in the vertical direction. This can prevent a long-term decrease in detection sensitivity.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG.
This will be described with reference to FIG.

(Embodiment 1) FIG. 1 is a block diagram showing a configuration of a laser beam detecting apparatus according to Embodiment 1 of the present invention. 1, blocks having the same functions as in the conventional example (FIG. 4) are denoted by the same reference numerals, and description thereof will be omitted. Here, 7 is a limit switch, 8 is an output terminal for outputting a signal from the limit switch 7, 9 is a shielding plate, 10 is a limit switch, 11 is an output terminal for outputting a signal from the limit switch 10, and 12 is temperature control. Media.

When the beam splitter 2 is mounted, the limit switch 7 is turned off when the ON signal is removed.
The FF signal is output from the output terminal 8. This signal is input to a control device (not shown) of the laser oscillation device 1 to control the laser beam 13 to be emitted only when an ON signal is output. Thus, it is possible to prevent the work 14 from being irradiated with an excessive laser output.

(Embodiment 2) As shown in FIG. 1, the limit switch 10 outputs an OFF signal when the shield plate 9 closes the detector 4 and an ON signal when the shield plate 9 is open. Output. This signal is transmitted to the laser oscillation device 1
The control is such that only the laser beam less than the maximum input to the detector 4 can emit the laser beam only when the ON signal is output to the controller (not shown). This makes it possible to prevent the detector from being irradiated with a laser beam that is greater than the maximum input.

(Embodiment 3) As shown in FIG. 1, the temperature of a medium 12 is controlled, and the detector 4 is made of oil or the like.
Is temperature controlled. FIG. 2 is a diagram showing the stability of the laser output of the present invention A and the conventional example B. This shows that the present invention is more stable.

(Embodiment 4) As shown in FIG. 1, a beam splitter 2, a condenser lens 3, and a detector 4 are installed in a vertical direction. FIG. 3 is a diagram showing detector outputs of the present invention A and the conventional example B, and a broken line C is an actual output. It can be seen that this arrangement makes the invention more stable over time.

[0018]

As described above, the first means of the present invention is that a beam splitter is provided with a limit switch, and a laser beam detecting device which outputs an OFF signal when the beam splitter is detached is used to remove an excessive laser beam by removing the beam splitter. It is possible to prevent light from being emitted to the work.

The second means is to provide a shielding plate provided with a limit switch in front of the detector, and to output an OFF signal when the shielding plate closes the front of the detector. It is possible to prevent the light from entering the detector and damaging the detector.

The third means is a laser light detecting device for controlling the temperature of the detector by using a medium whose temperature is controlled, so that the temperature rise due to incident laser light and the fluctuation of laser light due to outside air temperature can be reduced.

The fourth means can prevent a long-term decrease in detection sensitivity by using a laser beam detector in which the beam splitter, the condenser lens, and the photodetector are installed in a vertical direction.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a laser light detection device according to the present invention.

FIG. 2 is a diagram showing laser output stability of the present invention and a conventional example.

FIG. 3 is a diagram showing detector outputs of the present invention and a conventional example.

FIG. 4 is a block diagram showing a configuration of a laser beam detection device in a conventional example.

[Explanation of symbols]

1. Laser oscillation device 2. Beam splitter 3.
Condenser lens, 4 ... detector, 5 ... amplifier, 6, 8,
11: output terminal, 7, 10: limit switch, 9: shielding plate, 12: medium.

Claims (4)

[Claims] A beam splitter for dispersing the pulsed laser light extracted from the laser oscillation device, a condenser lens for condensing the dispersed pulsed laser light, and a dispersed pulsed laser light. A detector for detecting laser light, and an amplifier for amplifying a signal from the detector,
A laser light detection device provided with an output terminal for outputting the amplified signal, wherein the beam splitter has a limit switch, and when the beam splitter is attached, an ON signal is sent from the limit switch to the beam splitter. A laser beam detection device for outputting an OFF signal from the limit switch when the laser beam is removed. A beam splitter for dispersing the pulsed laser light extracted from the laser oscillation device, a condenser lens for condensing the dispersed pulsed laser light, and a condensed pulsed laser light. A detector for detecting laser light, and an amplifier for amplifying a signal from the detector,
A laser light detection device provided with an output terminal for outputting the amplified signal, comprising a shield plate having a limit switch in front of the detector, wherein the shield plate opens the front of the detector. ON signal from the limit switch, and when the shield plate is closed,
A laser light detection device for outputting an FF signal. 3. A beam splitter for dispersing a pulsed laser beam extracted from a laser oscillation device, a condensing lens for condensing the disperse pulsed laser beam, and a condensed pulsed laser beam. A detector for detecting laser light, and an amplifier for amplifying a signal from the detector,
A laser light detecting device provided with an output terminal for outputting the amplified signal, wherein the temperature of the detector is controlled by a medium whose temperature is controlled. 4. A beam splitter for dispersing pulsed laser light extracted from a laser oscillation device, a condensing lens for condensing the dispersed pulsed laser light, and a condensed pulsed laser light. A detector for detecting laser light, and an amplifier for amplifying a signal from the detector,
A laser light detection device provided with an output terminal for outputting the amplified signal, wherein the beam splitter, a condenser lens, and a detector for detecting laser light are installed in a vertical direction. apparatus.