JPH03198988A - Laser beam marking device - Google Patents

Abstract

PURPOSE:To carry cut scanning of a laser beam without causing its speed lowering by providing second scanning means to scan the laser beam in one direction at high speed between a laser beam oscillator and first scanning means on a laser beam optical path. CONSTITUTION:The laser beam marking device is provided with the laser beam oscillator 1 and the first scanning means 3, 4, 5 and 6 to scan the laser beam L in the X Y direction on a pattern mask 8. In addition, the marking position on a workpiece 12 of the laser beam L scanned is controlled by a position control means. A high-speed mirror 15 and a high-speed scanner 16 which are the second scanning means to scan the laser beam L in the one direction of X Y direction at least at the higher speed than the first scanning means are then provided between the laser beam osicillator 1 and the first scanning means (a first X mirror) 3 on the laser beam L optical path. By this method, the marking depth of each pattern can be maintained constant.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a laser marking device for marking a workpiece with a laser beam.

(Prior art) When marking a predetermined mark on a workpiece with laser light, the laser light is irradiated onto a pattern mask on which a pattern is formed, and the pattern is imaged onto the surface of the workpiece using a lens to mark the workpiece. There is a method in which the laser beam is moved relative to the workpiece to mark the workpiece in the same way as a handwriting.

The method using a pattern mask has the disadvantage that the pattern cannot be changed without replacing the pattern mask. Therefore, in order to eliminate these drawbacks,
There are two methods: using a disk-shaped pattern mask with the necessary pattern formed on the periphery, and rotating this pattern mask to change the pattern; There is a method of marking by scanning a laser beam, and recently the latter method is often adopted due to its high pattern flexibility and high marking speed.

In the case of marking by scanning a laser beam over a predetermined pattern, a scanner consisting of a galvanometer is used to scan the laser beam, and the rotation angle of the mirror is controlled by the scanner.

The above scanner is configured to control the rotation angle by sensing the rotation angle of the rotor using a position sensor and feeding it back to the motor drive current.

For example, in order to faithfully move the mirror in response to a predetermined input, factors such as loop gain and damping must be set to optimal values.

Since the value changes depending on input conditions such as amplitude and frequency, it is preferable to set it according to the input conditions.

If the scanner is used under input conditions different from the preset input conditions, problems such as a decrease in the amplitude of the mirror, abnormal vibrations, and a decrease in scanning speed occur.

Conventionally, a scanner that scans laser light in the X1Y directions has been set to be normally driven under predetermined input conditions. In other words, the scanner was set up to scan a relatively large area. Therefore, when scanning and marking a large area according to the input conditions, the scanner can be controlled easily and reliably, but when scanning a smaller area than the input conditions, the scanner's ability to follow the input , and the scanning speed becomes slower. As a result, the amount of heat input per unit area received by the workpiece increases, so the marking pattern formed by scanning a laser beam over a small area is deeper than the marking pattern formed by scanning a large area. It will be processed. As a result, when large patterns and small patterns coexist, their machining depths become uneven,
This may have led to a decrease in the quality of the pattern.

(Problem to be Solved by the Invention) As described above, according to the method of marking by scanning a laser beam, when scanning a small area, the followability of the scanner decreases and the scanning speed becomes slow, so it is difficult to mark a large area. The machining may be deeper than when marking by scanning.

This invention was made based on the above circumstances, and its purpose is to provide a laser marking device that does not reduce the scanning speed when scanning a small area with a laser beam. There is a particular thing.

[Structure of the Invention] (Means and Effects for Solving the Problems) In order to solve the above problems, the present invention includes a laser oscillator and a laser beam outputted from the laser oscillator that is
A laser marking device comprising a first scanning means for scanning in the Y direction and a position control means for controlling a marking position on a workpiece of a laser beam scanned by the first scanning means. A laser beam is transmitted between the laser oscillator and the first scanning means in the optical path of the first scanning means.
A second scanning means is provided for scanning in at least one direction of the XSY direction at a higher speed than the second scanning means.

According to such a configuration, when scanning a small area with a laser beam, if the second scanning means scans the laser beam at a high speed, the laser beam can be scanned at approximately the same speed as when scanning a large area. be able to.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

The laser marking device shown in FIG. 1 includes a laser oscillator 1. The laser marking device shown in FIG. As the laser oscillator 1, one that can provide a Q-switch output with high peak power is suitable.

The laser beam output from the laser oscillator 1 is converged by a first condenser lens 2 and enters a first X mirror 3. The laser beam reflected by the first X mirror 3 is made to enter a first X mirror 4 which together with the first X mirror 3 constitutes a first scanning means. The first X mirror 3 is driven by a first X scanner 5 made of a galvanometer at a predetermined rotation angle in the X direction, and the first X mirror 4 is rotated by a first Y scanner 6 at a predetermined rotation angle in the Y direction. It is designed to be driven at an angle. Therefore, the laser beam can be scanned in the X1Y directions by the first X mirror 3 and the first X mirror 4.

The laser beam reflected by the first X mirror 4 enters the relay lens 7. A pattern mask 8 is arranged on the output side of the relay lens 7.

In this pattern mask 8, large patterns P such as A, B, and C are formed on the upper side, and small patterns P2 such as albSc are formed on the lower side.

The second pattern passes through the predetermined pattern of the pattern mask 8.
The laser beam focused by the condensing lens 1o is sequentially reflected by a second X mirror 9 and a second X mirror 11 constituting a position control means to irradiate the workpiece 12. The rotation angle of the second X mirror 9 in the X direction is controlled by a second X scanner 13, and the rotation angle of the second X mirror 11 in the Y direction is controlled by a second Y scanner 14. It has become. Therefore, the laser beam that has passed through the predetermined pattern of the pattern mask 8 is positioned by the second X mirror 9 and the X mirror 11 of ff12 and irradiates the workpiece 12 to mark the predetermined pattern. It has become.

A high-speed mirror 15 constituting a second scanning means is installed on the optical path of the laser beam between the laser oscillator 1 and the first X mirror 3.

This high-speed mirror 15 is driven at a predetermined rotation angle in the Y-direction by a high-speed scanner 16 that can scan a laser beam in a small area at high speed in the Y-direction. That is, the high-speed scanner 16 is set so that it can scan a small area at a high frequency. On the other hand, the first X scanner 5 and the first Y scanner 6 are set so that they can scan a relatively large area at a lower frequency than the high speed scanner 16.

Note that the first XSY scanner 5.6 and the high-speed scanner 16
is set so that each mirror can move at the same angular velocity, that is, the laser beam can move at the same speed.

Next, the case where the workpiece 12 is marked by the laser marking device having the above configuration will be described.

First, when marking, for example, "A" out of the large pattern P1 formed on the upper side of the pattern mask 8 on the workpiece 12, the high-speed scanner 16 is stopped and the first
The X scanner 5 and the second Y scanner 6 are operated to scan the area "A" of the pattern P with laser light.

That is, FIG. 2(a) is a large pattern P.
When marking "A", the laser light indicates the area S1 to be scanned, and this area S1 has a horizontal dimension of 4.
ax, and the vertical dimension is 4ay. The first X mirror 3 is driven by the first X scanner 5, so that the laser beam is directed in a straight line as shown in FIG. At the same time, the first X mirror 4 is driven by the first Y scanner 6, so that the curve L shown in FIG.
The range in the vertical direction (Y direction) from 12ay to +2ay indicated by 2 is scanned at a frequency of 1/T. In this way, if the laser beam is scanned in the X direction and the Y direction,
Since the entire area S1 is scanned by laser light, the "80 patterns P1 formed on the pattern mask 8 can be marked on the workpiece 12. The marking position of "A1" on the workpiece 12 is ,
It can be set arbitrarily by changing the angle between the second X mirror 9 and the second Y mirror 11.

Next, when marking, for example, "a" of the small pattern P2 formed on the lower side of the pattern mask 8 on the workpiece 12, the first Y scanner 6 is stopped and the high speed scanner 16 and the first 3(a) shows an area S2 scanned by the laser beam when marking a small pattern P2 am.The horizontal direction of this area S2 is 2a.
x, and the vertical dimension is 2ay. The first X mirror 3 is driven by the first X scanner 5, so that the laser beam is directed in a straight line as shown in FIG. While scanning the area, the high-speed mirror 15 is driven by the high-speed scanner 16 at a frequency of 1/l in the range from -ay to +ay shown by the curve L4 in FIG. ) to scan repeatedly. In this way, by scanning the laser beam in the X direction and the Y direction, the entire area S2 is scanned, so that the small pattern P2 formed on the pattern mask 8 is scanned.
am can be marked on the workpiece 12.

The high-speed scanner 16 can scan the laser beam in the small area S2 corresponding to "a" at a higher frequency of 1/l than the first Y scanner 6. The laser light can be scanned without reducing the scanning speed due to such factors, and the moving speed of the laser light is set to be the same as when scanning the large area S1. ,
Since the small pattern P2 of a and the large pattern P of A'' can be marked at the same depth on the workpiece 12, the quality of marking can be improved.

In FIG. 3(b), the curve indicated by the broken line is a case where a small area S2 is scanned by the first Y scanner 6 used for a large area Sl, and in that case, the first Y scanner 6 is used for scanning a small area S2. The followability of the pattern decreases due to vibrations, etc., and a narrower range than the set range from -ay to +ay is scanned at a slower speed, which increases the amount of heat input per unit area and causes the pattern to become deeper. It will be processed.

Furthermore, if the high-speed scanner 16 is of a resonant type, it is possible to increase the marking speed when selecting patterns one by one and marking them like a typewriter.

In the above embodiment, the laser beam is scanned along the height direction (Y direction) in a small area using the high speed scanner, but the high speed scanner may also be used for scanning in the X direction. A high-speed scanner may be provided to scan both the X and Y directions at high speed.

[Effects of the Invention] As described above, the present invention provides a laser marking device in which a laser beam is scanned by a first scanning means, in which a laser beam is connected between a laser oscillator in the optical path of the laser beam and the first scanning means. Light above 1st
A second scanning means is provided which scans at a higher speed than the second scanning means. Therefore, if the second scanning means is used to scan a small area with a laser beam, scanning can be performed without reducing the speed of the laser beam, so scanning can be performed according to the size of the pattern to be marked. Even if the areas are different, the processing depth of each pattern can be made constant.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, and FIG. 1 is a perspective view of the general structure of the entire device, FIG. 2(a) is an explanatory diagram of a large area to be scanned with laser light, and FIG. Waveform diagram of scanning the above area in the X direction, Figure 2 (c)
is also a waveform diagram for scanning in the Y direction, Figure 3 (a
) is an explanatory diagram of a small area to be scanned with laser light,
FIG. 3(b) is a waveform diagram when the area is scanned in the X direction, and FIG. 3(c) is a waveform diagram when the area is similarly scanned in the Y direction. 1... Laser oscillator, 3... First X mirror (first
scanning means), 4...first Y mirror (first
scanning means), 5... first X scanner (first scanning means), 6... first Y scanner (
first scanning means), 8...pattern mask,
9...Second X mirror 11...Second Y mirror
12... Workpiece, 13... Second X scanner, 1
4...Second Y scanner, 15...High speed mirror (second
scanning means), 16... high-speed scanner (second scanning means), 16... high-speed scanner (second
scanning means).

Claims (1)

[Claims] A laser oscillator, a first scanning means for scanning a laser beam output from the laser oscillator in the X and Y directions on a pattern mask, and a first scanning means for scanning a laser beam outputted from the laser oscillator in the X and Y directions on a pattern mask, and scanning the laser beam scanned by the first scanning means on the workpiece. In the laser marking device, the laser beam is transmitted at a higher speed than the first scanning means between the laser oscillator and the first scanning means in the optical path of the laser beam. A laser marking device characterized in that a second scanning means is provided for scanning in at least one direction of the X and Y directions.