JPH07314165A - Laser device - Google Patents

Abstract

PURPOSE:To maintain the light quantity of an incident laser beam on an optical sensor approximately constant regardless of the opening and closing state of a shutter. CONSTITUTION:A reflection mirror 10 which perpendicularly reflects a part of the transmission beam T transmitted through a partial reflection mirror 2 is located at a shutter means 5. The reflectivity of the reflection mirror 10 is approximately equal to the reflectivity by an optical system 6 and a work piece 7. The reflected light which is reflected by falling onto the reflection mirror 10 and is made incident on the optical sensor 3 when the shutter means 5 is held closed and the reflected light which is reflected to return the original route by falling onto the optical system 6 and the work piece 7 and is made incident on the optical sensor 3 are equal to each other in the light quantity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser device for intermittently processing a workpiece by opening and closing a shutter while measuring laser light output.

[0002]

2. Description of the Related Art Conventionally, there is known a laser device of this type configured to intermittently interrupt a laser light output by opening and closing a shutter to process a workpiece, as shown in FIG. This will be briefly described. Reference numeral 1 is a laser oscillator, and a laser beam L emitted from the laser oscillator 1 is split into a reflected beam LR and a transmitted beam LT by a partial reflection mirror 2 such as a beam splitter. The reflected beam LR is received by the optical sensor 3 and converted into an electric signal. The electric signal is output and displayed on the output display circuit 4, and the laser oscillator 1 is provided for stabilizing the laser light output.
It is used to control the output value of. On the other hand, the transmitted beam LT is
The workpiece 7 is intermittently subjected to irradiation processing through the shutter means 5 and the optical system 6. That is, the transmission beam LT is controlled to enter the optical system 6 by the shutter means 5,
The light enters the optical system 6 only when the shutter means 5 is open,
The workpiece 7 is processed.

In addition to this, for example, Japanese Unexamined Patent Publication No. 58-204585.
The laser device disclosed in the publication is known. In this laser device, the partial reflection mirror 2 is omitted, and a feedback means for detecting the reflected beam reflected by the shutter and reflected by the output sensor and controlling the laser tube with this output value is provided. In such a laser device, since the shutter means has a function as a reflector, the beam splitter can be omitted.

[0004]

As described above, in the conventional laser device shown in FIG. 2, a part of the laser light output is detected by the optical sensor 3, and the output value is output by the output display circuit 4.
The output of the laser beam is displayed and is fed back to the laser oscillator to stabilize the laser light output. However, when the processing is actually performed, a part of the transmitted beam LT which hits the optical system 6 and the workpiece 7 is reflected and returns along the same path, so that when the shutter means 5 is closed,
The value of the laser light incident on the optical sensor 3 is different from when the shutter means is open. That is, when the shutter means 5 is open, the return light that is reflected by the optical system 6 and the workpiece 7 and returns, returns to the laser oscillator 1, is reflected again by the reflection mirror 9 of the laser oscillator 1, and the optical sensor 3 is returned. Therefore, the amount of laser light reflected by the partial reflection mirror 2 and incident on the optical sensor 3 when it is closed is different. As a result, there is a problem in that accurate output control cannot be performed and stable output cannot be obtained. Also,
The laser device disclosed in Japanese Unexamined Patent Publication No. 58-204585 can detect the light amount of the laser light only when the shutter means 5 is closed and is not processed, and cannot monitor the light amount during processing. There was a problem.

Therefore, the present invention has been made in view of the above-mentioned conventional problems, and an object thereof is to make the amount of laser light incident on the optical sensor substantially constant regardless of the open / close state of the shutter. Another object of the present invention is to provide a laser device capable of achieving the following.

[0006]

In order to achieve the above object, the invention according to claim 1 provides a mirror for reflecting a part of laser light emitted from a laser light source, and a light amount of a reflected beam reflected by the mirror. An optical sensor for detecting and a shutter means for intermittently blocking a transmitted beam transmitted through the mirror are provided, and when the shutter means is opened, the transmitted beam is incident on a workpiece through an optical system for processing. In the laser device, the shutter means is provided with an optical component that vertically reflects a part of the laser light. The invention according to claim 2 is the same as the invention according to claim 1,
The reflectance of the optical component is substantially equal to the reflectance of the optical system and the workpiece.

[0007]

In the present invention, the optical component reflects a part of the transmitted beam transmitted through the mirror and makes it incident on the optical sensor when the shutter means is closed. If the reflectance of this optical component is made approximately equal to the reflectance of the optical system and the work piece,
The amount of light reflected by the optical component and the amount of light reflected by the optical system and the workpiece and incident on the optical sensor when the shutter is open can be made substantially the same.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail with reference to the embodiments shown in the drawings. FIG. 1 is a schematic configuration diagram showing an embodiment of a laser device according to the present invention. In the figure, the same components as those in FIG. 2 are designated by the same reference numerals, and the description thereof will be omitted. In the figure, in this embodiment, a reflection mirror 10 as an optical component is provided on the side of the laser oscillator 1 of the shutter 5 so as to reflect a part of the transmitted beam LT transmitted through the partial reflection mirror 2 substantially vertically, that is, in the optical axis direction. It was set up. Other configurations are the same as those of the conventional device shown in FIG.

In such a configuration, the laser oscillator 1
The laser light L emitted from is reflected by the partial reflection mirror 2 by about 1% to become a reflected beam LR, and the remaining 99%.
Becomes the transmitted beam LT. The reflected beam LR is the light sensor 3
Is received and converted into an electric signal, and the output display circuit 4 displays the relative output value of the laser light. Further, it is fed back for controlling the output of the laser oscillator 1.
The transmitted beam LT is incident on the optical system 6 to irradiate the workpiece 7 when the shutter means 5 is open. At this time,
About 10% of the transmitted beam LT strikes the optical system 6 and the workpiece 7 and is reflected to become return light, which returns to the laser oscillator 1 through the original path. Then, the return light strikes the reflection mirror 9 of the laser oscillator 1, is reflected, and then is reflected by the partial reflection mirror 2 to enter the optical sensor 3 to give a disturbance. Therefore, if the amount of this disturbance is measured in advance and the reflection mirror 10 having the same reflectance (10%) is arranged in the shutter means 5, laser processing is performed even when the shutter means 5 is closed. The same amount of laser light as when the laser light is present can be made incident on the optical sensor 3 by the reflection mirror 10. Therefore, the output value of the optical sensor 3 is
Regardless of whether the shutter means 5 is open or closed, the value is always the same,
The laser output can be controlled with high accuracy.

[0010]

As described above, in the laser device according to the present invention, the shutter means is provided with the optical component for reflecting a part of the laser light, and the light reflected by the optical component is incident on the optical sensor. Therefore, the amount of laser light incident on the optical sensor can be made substantially the same regardless of whether the shutter means is open or closed. Therefore, it is possible to stably control the laser output, improve the processing quality, and contribute to the productivity. Further, as an optical component, it is only necessary to dispose a reflection mirror having a reflectance substantially the same as that of the optical system and the workpiece, so that the structure is simple and the conventional product can be easily modified. be able to.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a laser device according to the present invention.

FIG. 2 is a schematic configuration diagram showing a conventional example of a laser device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Laser oscillator, 2 ... Partial reflection mirror, 3 ... Optical sensor, 4 ... Output display device, 5 ... Shutter means, 6 ... Optical system, 7 ... Workpiece, 10 ... Reflection mirror.

Claims (2)

[Claims] 1. A mirror for reflecting a part of a laser beam emitted from a laser light source, an optical sensor for detecting a light quantity of a reflected beam reflected by the mirror, and a transmission beam transmitted through the mirror intermittently interrupted. In a laser device for performing processing by causing the transmitted beam to enter a workpiece through an optical system when the shutter means is opened, an optical device that vertically reflects a part of the laser light to the shutter means is provided. A laser device comprising parts. 2. The laser device according to claim 2, wherein the reflectance of the optical component is substantially equal to the reflectance of the optical system and the workpiece.