JPS63104389A - Laser output measuring apparatus - Google Patents

Abstract

PURPOSE:To perform more exact control of pulse laser oscillation, by detecting pulse laser beams by a photoelectric conversion element of high responsibility and averaging the detected pulse signal to obtain a pulse average output. CONSTITUTION:Part of pulse laser beams oscillated by a laser oscillator 1 is introduced into an integral sphere 2. In this sphere 2, the pulse laser beams are reflected in multiple numbers on an inner wall surface of the integral sphere and gradually absorbed into a phetoelectric conversion element 3. A beam current corresponding to a pulse change is outputted to an image display device 4 from the element 3. A pulse wave generated in accordance with a change in beam current is displayed on a screen of the device 4 so as to provide pulse wave observation. In a sampling averaging circuit 5, high-speed sampling of the pulse signal outputted from the element 3 is performed at 10 Hz or more so that pulse average output is generated. The pulse average output is inputted as a feedback signal to a pulse oscillation power source 7. In this way, while the pulse wave form is observed, exact control of pulse laser oscillation can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a laser output measuring device that simultaneously measures the average power of pulsed laser output and observes the pulse waveform.

[Prior Art] Generally, when measuring high-power pulsed laser light (or pulsed laser light after continuous wave laser light),
Due to the power resistance of the laser sensor and laser light absorption efficiency, multiple reflections are used to gradually absorb the Cl1i11 pulsed laser light into the laser sensor by repeatedly reflecting the GW/pulsed laser light introduced into the housing on the inner wall of the housing. The form called shape is used.

FIG. 3 describes a conventional laser output measuring method based on FIG. 0, which is a schematic configuration diagram of a conventional laser output measuring device using a multiple reflection type of CW pulsed laser light. ! The pulsed laser beam (1a) with a pulse waveform as shown in Fig. 04 has an entirely spherical shape (one segment sphere), and the entire inner wall surface is mirror-finished in a housing (
3) Introduced into the interior through the opening (3a). Then, the pulsed laser beam (la) is repeatedly reflected on the inner surface of the casing and gradually reaches the thermocouple (3b) provided on the inner surface of the casing (3).
absorbed into. The thermoelectromotive force generated in this thermocouple (3b) is proportional to the absorbed laser IB power, and by calibrating the power meter (4a) in advance, the average value of the pulsed laser output can be easily determined. can.

[Problems to be Solved by the Invention] Conventional laser output δIII determination devices measure pulsed laser using a thermoelectric conversion element in a conventional manner, and therefore can only measure the average output value of the pulsed laser. There were problems such as slow response.

This invention was made to solve the above-mentioned problems, and it provides a laser output that allows the pulse waveform to be observed during pulsed laser oscillation and that can output the pulsed laser average output value at high speed from the observation pulse signal input. The purpose is to provide a measuring device.

Means for Solving Problem L] The laser output measuring device according to the present invention includes a photoelectric conversion element that detects pulsed laser output, and an image display that displays an image of the pulse waveform of the pulsed laser output detected by the photoelectric conversion element. The device includes a pulse averaging circuit that averages the detected pulsed laser output and outputs an average output value.

[Function] According to the laser output measuring device of the present invention, since a photoelectric conversion element with high responsiveness and high infrared absorption rate is used as a laser sensor, it is possible to detect laser pulse output whose level changes instantaneously. By visualizing the output on an image display device, the laser pulse waveform can be observed accurately, and by averaging the detection output, the average value of the laser pulse output can be measured at the same time as the pulse waveform.

Embodiment] FIG. 1 is an overall configuration diagram showing an embodiment of the laser output measuring device of the present invention. In FIG. (3) is a spherical casing (integrating sphere) introduced for the purpose of
2) Photoelectric conversion element attached to the inner surface (infrared sensor: Ge (Au), Ge (Hg), Ge (Gu),
or CdHgTe, etc.), (4) is an image display device that visualizes the sensor output, (5) is a sampling averaging circuit that samples the pulse output, integrates and averages the sampling output, and (it) averages the l. An average output circuit (7) is a laser oscillation power supply that outputs an output at a predetermined level.

The operation of this embodiment will be explained based on the configuration described in Section 2. A part of the pulsed laser light emitted from the laser oscillator (1) is introduced into the integrating sphere (2). In the integrating sphere (2), the pulsed laser beam undergoes multiple reflections on the inner wall surface of the integrating sphere and is gradually absorbed by the photoelectric conversion element (3). As a result, the photoelectric conversion element (3) converts the photocurrent according to the pulse change into the image display device (4).
). The image display device (4) into which the photocurrent is input displays the pulse waveform generated based on the change in the photocurrent on the screen, and provides the pulse waveform observation. On the other hand, the sampling averaging circuit (5) performs high-speed sampling of the pulse signal (see Figure 2) output from the photoelectric conversion element (3) at 10 Hz or higher, and generates a pulse average output by integrating the sampling output. do. This pulse average output is also input as a feedback signal to the pulse oscillation power supply (7). As described above, since pulse waveform information and a feedback signal for controlling pulsed laser oscillation are obtained from the same photoelectric conversion element (3), accurate pulsed laser oscillation control can be performed while observing the pulse waveform.

[Effects of the Invention] As described above, according to the present invention, since pulsed laser light is detected by a highly responsive photoelectric conversion element,
The pulse waveform can be reproduced with high fidelity on an image display device, and the pulse average output can be quickly obtained by averaging the detected pulse signal, so laser processing can be performed from both the pulse waveform and the pulse average output value. This has the effect of more accurately controlling the oscillation of a pulsed laser that is optimal for use.

[Brief explanation of the drawing]

Fig. 1 is a configuration diagram showing an embodiment of the laser output measuring device of the present invention, Fig. 2 is a pulse waveform diagram showing a laser pulse waveform and a pulse waveform monitor signal, and Fig. 3 is a diagram of a conventional laser output measuring device. The configuration diagram and FIG. 4 are waveform diagrams showing laser pulse waveforms and output monitor signals in a conventional device. In the figure, (1a) is the GW/pulsed laser beam, (2) is the housing (integrating sphere), (3) is the photoelectric conversion element,
(4) is an image display device, (5) is a sampling averaging circuit, and (6) is an averaging output circuit. In each figure, the same reference numerals indicate the same or corresponding parts. Agent Masuo Oiwa Figure 1 Figure 2 Figure 3 Figure 4

Claims (2)

[Claims] (1) A spherical housing having an inner wall surface that multiple-reflects the introduced pulsed laser light, a photoelectric conversion element for absorbing the pulsed laser light installed inside the housing, and light output from the photoelectric conversion element. An image display device that generates and displays a laser pulse waveform based on current, and a pulse averaging circuit that averages the pulsed laser output signal output from the photoelectric conversion element to generate an averaged output value. A laser output measurement device featuring: (2) The laser output measuring device according to claim 1, wherein the photoelectric conversion element is a semiconductor infrared sensor.