JPS6015440B2 - Laser processing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a laser processing device having a laser beam scanning function.

Conventionally, laser processing equipment using the laser beam scanning method is the first
It was constructed as shown in Fig. 2 and Fig. 2.

That is, the conventional laser processing apparatus shown in FIG.
It consisted of a condenser lens 3 that condenses laser light reflected from the laser beam. In this laser processing equipment, an oscillator (
A laser beam 1 irradiated from a mirror (not shown) is scanned while being reflected by a mirror 2 that moves in an oscillating manner, and this scanned laser beam is focused on a workpiece 4 by a condenser lens 3, and It is processed. However, in order to scan the irradiated laser beam and laser process the workpiece 4, it is necessary to prepare the mirror 2. Mirror 2 like this
There is a limit to installing a drive device that swings at high speed. In addition, in conventional laser processing equipment, in order to improve the positional accuracy of optical scanning, it is necessary to control the swinging motion of the mirror 2 by taking into account the hysteresis characteristics of the drive device, which requires advanced technology and The disadvantage is that it becomes a big deal. On the other hand, the conventional laser processing apparatus shown in FIG.
It consisted of a table 6 and a motor 7 that moved the XY table 6 in two directions.

In this laser processing device, the laser beam focused by the condensing lens 5 is relatively scanned over the workpiece 4 by moving one or both of the XY tables 6 in each direction by the motor 7. Object 4 is laser processed. However, in this laser processing device, in order to perform arbitrary reciprocating motion against the inertial force of the XY table 6, it is necessary to prepare a motor 7 with a large output, and the table 6
It was practically difficult to make the reciprocating motion at high speed.
Furthermore, this laser processing apparatus has the disadvantage that an XY table 6 whose position is controlled with high accuracy is required in order to improve the scanning position accuracy.

The purpose of the present invention is to eliminate the above-mentioned conventional drawbacks, to make the optical system for scanning the laser light beam smaller and lighter, and to make a small spot shape in a large processing range by rotating this optical system at high speed and continuously. The present invention provides a laser processing device that processes a workpiece using a laser beam.

That is, one of the present inventions is to provide a coarse first prism and a second prism set for scanning the scissor spot on a straight line, and to separate the first prism set and the second prism from each other. According to another aspect of the present invention, the scanning directions of the coarse laser spots are arranged so as to be perpendicular to each other, and the laser spots scan within a two-dimensional plane to perform laser processing on the workpiece. One is a plurality of prisms that give a deflection angle to the irradiated laser beam, a means for rotating the plurality of prisms around the optical axis of the laser beam, and a rotation of the prism rotated by the means. The phase of the angle is detected, and when the phase of the rotation angle of the prism is within a preset phase range, the irradiated laser light is blinked or the intensity is modulated to laser process an arbitrary pattern. This is what I did. The present invention will be specifically described below based on embodiments shown in the drawings.

3 to 5 are diagrams for explaining the principle of the laser processing apparatus of the present invention. In FIG. 3, the refractive index m,
Incident light 9 that has entered the isosceles triangular prism 8 with an apex angle q is output as refracted light 10 that is bent by an angle 6 by the prism 8. Note that when the apex angle Q is small, the value of the deflection angle 6 is approximately expressed by the following equation '1}. 6=(m-1)a......[1} When the prism 8 formed in this way is rotated around the light beam of the incident light 9, the refracted light with a deflection angle of 6 rotates by one river, and is spread over a certain distance. Draw a circle in separate planes.

Next, two such prisms 8 are prepared, and the respective prisms 8a and 8b are arranged in parallel along the optical axis of the incident light 9 as shown in FIG. The deflection angle of prisms 10a and 10b is 6, 62, and the angle formed by the directions of the top sides 11a and 11b of both prisms 8a and 8b is 8.
Then, the composite deflection angle 6 formed by the two prisms 8a and 8b is expressed by the following equation (2). 6nino 6,2+
622 plus 26,6 yo os3 (2) Here, the prisms 8a and 8 whose deflection angles 6 and 62 are equal
When b is prepared, the combined deflection angle 6 of both prisms 8a and 8b has the following relationship expressed by the '31 equation, and changes cosinally.

6=2M.

No. S (however, 61 = 62:60).・・・． ...'3' Thus the deflection angle is 6.

When both prisms 8a and 8b with the same angular velocity are prepared and both prisms are rotated in opposite directions at the same angular velocity, the light passing through both prisms performs linear motion as a combination of circular motion that rotates in opposite directions at the same angular velocity. Note that from the relationship of the above equation '3}, the range of the composite deflection angle 6 holds the relationship of the following equation {4]. 26.

S6S-26. ......'4} On the other hand, in FIG.
3 is made incident on the condensing lens 12 having a focal length of n, the light is focused on an off-axis focal point 15 which is a distance of a mountain from the focal point 14 on the light tree. The values of this have the relationship of the following formula (5).
} and '5}, the two-sided prisms 8a and 8b (
The combined refracted light 17 output from the condenser lens 1
2, the linear movement of the light spot on the light surface 16 is obtained by the following equation {6}.

=26J■S building......■ Next, one embodiment of the laser processing apparatus of the present invention will be described based on FIG.

A pair of prisms 8a and 8b are formed of isosceles triangular prisms made of the same material and having the same apex angle.

Further, the prisms 8a and 8b are embedded in respective cylindrical support members (not shown) and are supported rotatably around the optical axis of the irradiated laser beam 1. Each of the support members (not shown) is connected to a drive device, such as a motor, which rotates and drives the support member, such as a motor, via a rotational connection mechanism, such as a gear, provided on the outer periphery. 18 and 19 are a pair of prisms 8a and 8b
, and are arranged so as to be perpendicular to the direction of rotation of the laser light around the optical axis.

4 is a workpiece to be subjected to scissor processing.

Reference numeral 12 denotes a condensing lens that condenses laser beams scanned in a straight line and outputted from the prisms 8a and 8b, and is provided stationary between the prisms 18 and 19 and the workpiece 4.

In this way, the laser beam 1 is scanned through a pair of prisms 8a and 8b that rotate in opposite directions at the same angular velocity. That is, the paper 18 of each prism passes through the prism sets 18 and 19.
and 19 are scanned with light in the x and y directions, which are perpendicular to the rotational direction of the optical axis, and are condensed and irradiated onto the workpiece 4 by the condenser lens 12. Laser process object 4. As a result, the laser processing device scans the laser beam two-dimensionally and processes the workpiece 4 with the laser beam in a state where the working distance is large and the spot diameter is small.

Furthermore, another embodiment of the laser processing apparatus of the present invention will be described based on FIG.

4 and 12 are the same as those in the embodiment shown in FIG. 6, 4 is a workpiece, and 12 is a condenser lens.

20 is a Caesar oscillator.

Reference numeral 22 denotes an optical scanning section which directly receives and scans the laser beam from the laser oscillator 20 without enlarging it, and is composed of one or more sets of inverting prisms 8a and 8b.

A laser control section 23 controls the intensity or blinking of the laser beam output from the laser oscillator 20.

Reference numeral 24 denotes an optical scanning control section, which drives the prisms 8a and 8b of the optical scanning section 22 in reverse at a constant speed, detects the rotation phase, and outputs a signal to the laser control section 23 to control the laser beam. be.

With the above structure, the laser beam output from the laser oscillator 20 directly enters the optical scanning unit 22, and is condensed and irradiated onto the workpiece 4 by the condenser lens 12, and the workpiece 4 is scanned by the laser beam. Process. At this time, the optical scanning detection section 24 detects the optical scanning section 3.
The prisms 8a and 8b are driven to rotate in reverse rotation at a constant speed, and the rotational phase of each prism 8a and 8b is detected and a signal for turning the laser beam on and off is sent to the laser control unit 23, so that the prisms 8a and 8b are rotated at an arbitrary light transmission position. Appropriate laser light intensity or blinking is provided. In this way, the phase of the rotation angle of the inverted prisms 8a and 8b is detected, and the laser beam is blinked or intensity-modulated at the set position, and any part on the straight line or plane scanned by the laser beam is arbitrarily scanned. It has a large working distance and can be machined with a machining strength of 4 mm.
Further, an example of the operation of the embodiment of the present invention will be explained based on FIG. The laser beam 1 is transmitted through a pair of first rotating prisms 18 with a large deflection angle and a second rotating prism 19 with a small deflection angle.
Through the condensing lens 12, the condensed light is irradiated onto the workpiece 4, and laser processing is performed. At this time, if both prism sets are rotated at the same speed and both prisms 18 and 19 are rotated in the opposite direction, the focal point will draw a tachibana circle.

The deflection at prisms 18, 19 is 6, . 62, and the focal length of the condensing lens 12 is the length of the long axis (62).
．． The machine circle is 162) na and the short axis is (6.-62) na.

FIG. 8 shows the locus of the condensing point when prisms arranged in the same manner as in FIG. 6 and having the same scanning angle are rotated in opposite directions at a rotational speed ratio of 2:1. Equal like this,
Alternatively, two or more rotating prisms with different deflection angles are used and rotated in the same or different directions, or in the same and different directions with equal or different rotational speeds, or partially equal and partially different rotational speeds, and then rotated for one more rotation. By changing the rotational speed inside these prisms, the light passing through these prisms can be deflected to any angle, and the trajectory of the focal point on the focal plane of the lens can be changed to a bridge circle or a regular leaf line, as shown below. It can be drawn as a locus of point P(x, y) as expressed by the relationship of equation '7). However, yi is the distance between the condensing light on the lens optical axis and the condensing point determined by the deflection angle by the i-th prism and the focal length of the condensing lens, and Wi is the angular velocity of rotation of the i-th prism. wit is the i-th f at time t.

lj is the angle in the direction of the base of the prism, and aio is the initial angle of the prism. As explained above, the present invention provides a first prism rope and a second prism rope for scanning the laser spot in a straight line, and each of the first prism rope and the second prism pair Since this laser processing device is arranged so that the scanning directions of the coarse laser spots are perpendicular to each other, the laser spot scans the workpiece in a two-dimensional plane with high responsiveness using a small and lightweight prism scanning mechanism. It has the effect of being able to be sewn.

Further, according to the present invention, by detecting the rotational phase of the prism, the laser beam can be modulated at any optical scanning position and a necessary linear or planar shape can be laser-processed. Further, according to the present invention, since the laser beam is scanned simply by rotating the prism, the apparatus for scanning the laser beam can be made lightweight and compact, and the workpiece can be scanned by scanning the laser beam at high speed. Can be laser processed.

[Brief explanation of drawings]

1 and 2 are schematic configuration diagrams showing a conventional laser processing device, FIGS. 3, 4, and 5 are diagrams for explaining the principle of the laser processing device of the present invention, and FIG. 6 7 is a schematic block diagram showing another embodiment of the laser processing apparatus of the present invention, and FIG. 8 is a schematic block diagram showing another embodiment of the laser processing apparatus of the present invention. FIG. 3 is a diagram showing an example of a laser-processed figure drawn by the laser processing device. 4... Workpiece, 8, 8a, 8b... Prism, 9... Laser light, 10, 10a, 10b
．．・・・． ...Refracted light, 12... Condensing lens, 1
6...Focusing surface, 17...Synthetic refracted light,
18, 19... Prism roughness, 20... Laser oscillator, 22... Light scanning unit, 23... Laser control unit, 24... Light scanning control unit . Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8

Claims (1)

[Scope of Claims] 1. A laser oscillator that irradiates a laser beam, a set of two first prisms that give equal deflection angles to the laser beam, and a set of two first prisms that apply each of the first prisms to the laser beam. a first means for scanning the laser beam in a straight line by rotating the laser beam in opposite directions at mutually equal angular velocities about the main axis of the laser beam;
For the laser light transmitted through the first set of prisms,
A set of two second prisms giving equal deflection angles to each other, and each of the second prisms is rotated in opposite directions at mutually equal angular velocities about the main axis of the laser beam, thereby directing the laser beam to the first prism. A laser processing device comprising: second means for scanning in a straight line substantially perpendicular to the linear scanning direction by the means; and a lens for condensing the laser beam transmitted through the second prism set onto a workpiece. 2. A laser oscillator capable of intensity modulation including blinking, a plurality of prisms that directly receive the laser beam output from the laser oscillator and provide a deflection angle, and the prisms are rotated around the main axis of the laser beam. and laser control means for detecting the rotational phase of the prism and performing intensity modulation including blinking of the laser beam when the phase is within a preset range.