JPH08187582A - Laser picture-drawing device - Google Patents

Abstract

PURPOSE: To enable satisfactory picture-drawing by giving feedforward control of a laser beam quantity and thereby obtaining a stable line width for picture- drawing. CONSTITUTION: In the memory 202 of a controller 200, the pattern of a laser beam quantity is stored which is related to the moving speed pattern of a first and a second table 13, 14; and a position command is given to a table driver 204 and also to a position command counter 203. The pattern stored in the memory 202 is read out, the pattern thus read out is given to a D/A converter 205, and the pattern output of the laser beam quantity is thereby given to a power servo circuit 7. With a feedforward control over the power control AOM in the power servo circuit 7, the laser beam quantity to be given to the optical head is controlled, causing no detection delay like a feedback control, and producing a stable line width for a satisfactory picture-drawing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser drawing apparatus, and more particularly to a laser drawing apparatus which draws a fine pattern using laser light.

[0002]

2. Description of the Related Art As a laser drawing apparatus for drawing a fine pattern using a laser beam, there are those proposed in Japanese Patent Laid-Open Nos. 4-10613 and 4-10614.

FIG. 5 is a block diagram showing the overall structure of the proposed laser drawing apparatus. In FIG. 5, a He—Cd laser tube 1 is provided as a laser light source, and a writing laser 101 emitted from the He—Cd laser tube 1 is reflected by a mirror 2 and is incident on a power control AOM 3. The power control AOM 3 is for controlling the laser output of the writing laser 101. AOM3 for power control
The writing laser 101 whose output has been adjusted by is incident on the laser power monitor 4. The laser power monitor 4 monitors the writing laser 101, supplies a monitor output to the power servo circuit 7, and the power servo circuit 7 feedback-controls the power control AOM 3. The monitored writing laser 101 is reflected by the mirror 5 and is incident on the optical head 12.

The optical head 12 is provided above the XY table 11. The XY table 11 includes a first table 13 and a second table 14. First
The table 13 is movable in the first direction (X direction). The second table 14 is movable in a second direction (Y direction) orthogonal to the first table. And
A workpiece (not shown) is provided on the XY table 11. The moving speeds of the first table 13 and the second table 14 are detected by the position detection linear encoder, and the detection direction output pulse signals in the X direction and the Y direction are f / V conversion circuits 15a, 15 respectively.
given to b. Each of the f / V conversion circuits 15a and 15b converts the frequency of the applied pulse signal into a voltage, and the output voltage is applied to the power servo circuit 7. The power servo circuit 7 uses the given voltage value as a command value for laser power control to feedback-control the power control AOM 3.

That is, in the conventional laser drawing apparatus, the actual moving speeds of the first table 13 and the second table 14 are detected and controlled.

[0006]

However, in the above-mentioned proposed laser drawing apparatus, there is a detection delay due to f / V conversion when detecting the table speed. Therefore, there is a difference between the actual table speed and the actual table speed, so that the amount of laser light corresponding to the table moving speed cannot be obtained, and there is a problem in that adjustment for stabilizing the drawing line width is difficult. In addition, slight fluctuations in the laser light amount occur according to the ripples associated with f / V conversion. Therefore, there is also a problem that the drawing line width varies. Further, since the result of the speed detection of the table is used, the control of the laser light amount is feedback. Therefore, there is a problem that it is difficult to cope with drawing when the change in the laser light amount is large.

Therefore, an object of the present invention is to solve the above-mentioned problems, to control the laser light amount in a feed-forward manner, to suppress and stabilize the fluctuation of the drawing line width, and to obtain good drawing. It is an object of the present invention to provide a laser drawing apparatus capable of performing the above.

[0008]

According to a first aspect of the present invention, there is provided a laser drawing apparatus for drawing a workpiece with a laser beam, wherein the workpiece provided on the laser drawing apparatus is XY.
An XY table movable to a plane, a laser output unit for outputting a laser beam to a workpiece, a storage unit storing a light amount pattern of the laser beam to be output by the laser output unit, and a moving XY table, The storage means reads the light quantity pattern of the laser light stored therein, and the control means controls the laser output means so that the laser output means outputs the laser light according to the light quantity pattern.

According to a second aspect, the storage means of the first aspect is X
The light quantity pattern of the laser light associated with the movement pattern of the Y table is stored, and the control means stores the laser light stored in the storage means in response to the command value for moving the XY table being given. The reading unit includes a reading unit that reads the light amount pattern of the light, and a laser supply unit that supplies the laser output unit with laser light corresponding to the light amount pattern of the laser light read by the reading unit.

[0010]

The laser drawing apparatus according to the present invention stores the light quantity pattern of the laser light to be output to the workpiece, reads the stored light quantity pattern of the laser light, and responds to the read light quantity pattern. Since the laser light is output to the workpiece, the light quantity of the laser light can be determined and controlled in a feedforward manner.

Further, the laser drawing apparatus according to the present invention stores the light quantity pattern of the laser light associated with the movement pattern of the XY table, and feeds the more optimum light quantity of the laser light with respect to the movement of the XY table. It can be determined and controlled in a foreground manner.

[0012]

1 is a block diagram showing the overall construction of a laser drawing apparatus according to an embodiment of the present invention. A part different from the conventional example shown in FIG. 5 will be particularly described with reference to FIG.

A controller 200 is provided in place of the f / V conversion circuits 15a and 15b. Controller 2
00 is the first table 1 that constitutes the XY table 11.
In order to control the movement of the third and second table 14,
The X-direction movement command value is given to the first table 13, the Y-direction movement command value is given to the second table 14, and the laser power servo circuit 7 is given the command value of the laser light amount in a feedforward manner. The command value of the given laser light amount is given by the first and second tables 13 and 14.
Is associated with the moving speed pattern of No. 1 by a predetermined relationship.

FIG. 2 is a diagram showing the internal configuration of the controller 200 of FIG. 1, and FIG. 3 is a diagram for explaining the operation of the configuration shown in FIG. 2. In particular, FIG. , The horizontal axis indicates the moving direction x, and the vertical axis indicates the movement command speed pattern g.
FIG. 3B is a pattern diagram showing (x). In FIG. 3B, the horizontal axis represents the moving direction x and the vertical axis represents the laser light amount pattern f.
FIG. 3C is a pattern diagram showing (x), and FIG. 3 (c) is a diagram showing the moving direction x on the horizontal axis and the actual speed of the table on the vertical axis.

A specific description will be given below with reference to FIGS. 2 and 3. The controller 200 includes a system controller (computer) 201, a memory 202 as an example of a storage unit, and a position command counter 203 as an example of a reading unit.
A table driver 204 and a D / A converter 205.

Here, the first table 13 is moved in the X direction to x.
Consider the case of moving from ₀ to x ₃ . The system controller 201 calculates an optimal speed pattern of g (x) as shown in FIG. 3A from the dynamic characteristics of the table. Further, the system controller 201 determines the pattern of the laser light amount corresponding to the commanded speed pattern g (x) at the optimum position as f (x) as shown in FIG. Then, the determined write pattern is written in the memory 202. As a result, the memory 202 stores the laser light amount pattern associated with the position command speed pattern.

Next, when the table is actually moved, the system controller 201 outputs a position command to the table driver 204 to move the table in the pattern of g (x), and counts this position command. The position command counter 203 is also output. The position command counter 203 reads the pattern of the laser light amount stored in the memory 202 by counting the position command. The read pattern read from the memory 202 is given to the D / A converter 205. The D / A converter 205 uses the D / A
(Digital / analog) conversion is performed and a laser light amount pattern as a command value to the laser power servo circuit 7 is output.

As a result, although the table actually has a shape slightly different from the commanded speed pattern as shown in FIG. 3 (c) due to the relationship of the dynamic characteristics of the table, it moves substantially as commanded.

In this way, the amount of laser light at the time of drawing is prepared as an optimum pattern for the actual speed of the table and the drawing pattern measured in advance. Then, the laser light amount is controlled in a feed-forward manner. As a result, a stable drawing line width can be obtained. In particular, when drawing a circle, it is necessary to connect the start point and the end point cleanly, but by performing control in a feed-forward manner as in the present invention, it is possible to draw a good circle. Further, even if the dynamic characteristics (particularly the followability) at the time of moving the table in the table drive servo system are insufficient, the pattern of the laser light amount may be set in accordance with this. As a result, good drawing becomes possible.

In the optical head used in the present invention,
The lens exchange mechanism proposed in Japanese Patent Application No. 5-189801 may be provided.

FIG. 4 is a side view showing such a lens exchange mechanism. The lens exchange mechanism in FIG. 4 is an electric revolver unit 9, and the electric revolver unit 9 is used.
Is attached to the tip of the optical head 12 of FIG.
A mirror 6 is provided in the optical head 12. The writing laser 101 reflected by the mirror 5 shown in FIG. 1 is further reflected in the vertical direction by the mirror 6 and is incident on the electric revolver unit 9. The electric revolver unit 9 can electrically switch a plurality of lenses 10 having different focal lengths. Electric revolver unit 9
The writing laser 101 guided to is focused by the lens 14 on the surface of the workpiece 100 placed on the table. At this time, the diameter of the condensed laser beam is changed by rotating the electric revolver unit 9 and polarizing the lens. As a result, the width of the drawn line can be changed.

By providing such a lens exchange mechanism, the problems of the laser drawing apparatus proposed in Japanese Patent Application Laid-Open No. 4-10613 and Japanese Patent Application Laid-Open No. 4-10614 are solved. Here, the problems will be described. In the above-mentioned proposed laser drawing apparatus, a lens for narrowing down the laser light is fixedly attached to the tip of the optical head. Therefore, there is a problem that the range of the line width that can be drawn by the laser light emitted from the optical head is limited. For example, if a lens is used to reduce the line width, it is impossible to draw a thick line at a time, and a thin line needs to be drawn many times along the line. There was a problem. In particular, there is a problem that it takes a long time to draw a large area painting pattern.

On the other hand, provision of the lens exchange mechanism shown in FIG. 4 solves the above problems.
That is, for example, a focal length capable of drawing a line width of about 1 μm to several tens of μm as the lens 10 can be set, and an effect that the width corresponding to various patterns is widened is obtained. In addition, a thick line width can be provided, and the drawing time can be significantly shortened even with a large-area filling pattern.

[0024]

As described above, according to the present invention, the light quantity pattern of the laser light to be output to the workpiece is stored, the stored light quantity pattern of the laser light is read, and the read laser is read. Since the laser light is output to the workpiece with the light quantity pattern of the light, the light quantity of the laser light can be controlled in a feed-forward manner, a stable drawing line width can be obtained, and good drawing can be performed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an overall configuration of a laser drawing apparatus according to an embodiment of the present invention.

2 is a block diagram showing an internal configuration of the controller of FIG. 1. FIG.

FIG. 3 is a diagram for explaining the operation of the controller shown in FIG.

4 is a side view of a lens exchange mechanism attached to the tip of the optical head of FIG.

FIG. 5 is a block diagram showing an overall configuration of a conventional laser drawing apparatus.

[Explanation of symbols]

 1 He-Cd Laser Tube 2, 5, 6 Mirror 3 Power Control AOM 4 Laser Power Monitor 7 Power Servo Circuit 9 Electric Revolver Unit 10 Condenser Lens 11 XY Table 12 Optical Head 13 First Table 14 Second Table 100 Workpiece 101 Writing laser 200 Controller 201 System controller (computer) 202 Memory 203 Position command counter

Claims (2)

[Claims] 1. A laser drawing apparatus for drawing a workpiece with a laser beam, comprising: an XY table provided on the workpiece for moving the workpiece in an XY plane; and a laser beam for the workpiece. Laser output means for outputting, storage means for storing the light quantity pattern of the laser light to be output by the laser output means, and reading the light quantity pattern of the laser light stored in the storage means when the XY table is moved. Together with a control means for controlling the laser output means so that the laser output means outputs laser light in the light amount pattern.
Laser drawing device. 2. The storage means stores a light amount pattern of laser light associated with a movement pattern of the XY table, and the control means is given a command value for moving the XY table. In response to this, the reading means for reading the light quantity pattern of the laser light stored in the storage means, and the laser light according to the light quantity pattern of the laser light read by the reading means are supplied to the laser output means. The laser drawing apparatus according to claim 1, further comprising a laser supply unit.