JPH1058179A - Laser beam machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To continuously increase/decrease a spot diameter without making the irradiating spot periphery of a laser beam out of focus by aligning the optical axis of an optical system, which emits the laser beam for a work, and the optical axis of introducing means, which introduces a laser beam in the optical system and fixing the introducing means to a moving means movable along the optical axis. SOLUTION: A work 100 is set on a XY table 2 and machined by a laser beam. A spot diameter of laser beam is changed in accordance with a pattern width as a machining position of work travels. By operating a zoom motor 15, the spot diameter is changed with changing the focus of a zoom lens 8 through a gear 16 and a focus gear 14. The work 100 is irradiated with the laser beam from an optical fiber 9, which is reflected with a beam splitter 4 in irradiating cylinder 7, through an object lens 3 in a prescribed spot diameter. The laser beam, after irradiating, is reflected and forms a image on a CCD camera 6 through an image forming lens 5, thus, the image is observed by a monitor 17.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a laser processing apparatus.

[0002]

2. Description of the Related Art As a prior art, Japanese Patent Laid-Open No. 4-251686
Will be described. This conventional technique is a laser processing apparatus which enables confirmation and observation of a processing position and a processing range of a workpiece. That is, the optical path of the laser light and the visible light are made common so that visible light having the same shape as the laser light spot shape on the workpiece is irradiated to the laser light irradiation position of the workpiece, and an arbitrary aperture is provided in the optical path. It has a light-shielding plate with an opening that can be changed into a shape, and by changing the shape of the opening according to the size of the processed part, the size of the laser light spot and the size of the visible light spot can be changed simultaneously. It has a structure that can be used.

[0003]

However, according to the embodiment of the prior art, the laser light and the visible light, which are parallel rays, are diffused rays after passing through the opening of the light shielding plate. It is disclosed that the light is condensed on a processed portion of a workpiece through an aberration corrector, a mirror, and two objective lenses.

However, the light that has passed through the opening of the light-shielding plate is made up of parallel rays corresponding to the diameter of the opening and diffused light that interferes with the edges of the opening and diffuses. Become. Therefore, although it is illustrated that each light beam is condensed at one point on the workpiece, in reality, it becomes a spot where the light beam is fuzzy and the light amount becomes uneven.

[0005] In such a state, when the processing portion is minute or there is a portion that cannot be irradiated in the vicinity of the processing portion, there arises a drawback that accurate processing cannot be performed and the like. Since a part of the laser beam is cut, the output must be changed in accordance with the size of the aperture in order to keep the processing energy constant, which has a disadvantage that the apparatus becomes complicated.

Another embodiment discloses that the light-shielding plate is released and only parallel rays are condensed on the processed portion of the workpiece through the objective lens. In this case, the spot diameter is constant. If the area of the processed part is not constant, the spot diameter must be changed by changing the distance between the objective lens and the workpiece, or two-dimensional scanning must be performed with the spot diameter kept constant. However, it has the drawback that the whole apparatus becomes complicated and the processing time becomes long.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems, and has as its object to provide a laser processing apparatus which can use laser light efficiently with a simple configuration.

[0008]

According to the present invention, there is provided a laser processing apparatus, comprising: a laser oscillator; an optical system for emitting laser light emitted from the laser oscillator toward a workpiece; And an observation means for observing a processing state, wherein an optical axis of the introduction means coincides with an optical axis of the optical system, and the introduction means is movable along the optical axis. It is characterized by being fixed to the moving means.

(Operation) According to the above configuration, the spot diameter on the workpiece is arbitrarily and continuously enlarged in a focused state by moving the introducing means toward and away from the optical system along the optical axis. Since it is possible to reduce the size, a spot having a uniform light amount without loss of the laser light emitted from the laser oscillator can be obtained.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. (Embodiment 1) Embodiment 1 will be described with reference to FIGS. FIG. 1 is an overall view of the first embodiment partially shown in cross section.

FIG. 2 is a partially enlarged view of the workpiece shown in FIG. In FIG. 1, an XY table 2 on which a workpiece 100 is placed and which is movable in the XY directions is provided in an apparatus main body 1. Further, an irradiation system 7 having an optical system including an objective lens 3 and a beam splitter 4 for irradiating the workpiece 100 with laser light, and an observation unit including an imaging lens 5 and a CCD camera 6 for observing a processing state is provided. Workpiece 100
It is arranged facing.

The apparatus main body 1 is provided with an introduction means at a position where laser light is introduced into the beam splitter 4. The introduction means comprises a zoom lens 8 and an optical fiber 9 for emitting laser light coaxially with the optical axis of the zoom lens 8. The zoom lens 8 has a focus gear 14 as a moving means A for moving the focal length. 1 is engaged with the gear 16 of the zoom motor 15 which is fixed at 1.

The optical fiber 9 is fixed to a moving means B movable along the optical axis of the zoom lens 8. The moving means B includes a moving table 10 that fixes the optical fiber 9 and moves along the optical axis, and a base 11 that guides the moving table 10.
And a motor 13 having a rotating shaft 12 fixed to the base 11 and screwed into a female screw provided on the movable base 10.

The other end of the optical fiber 9 is connected to a laser oscillator (not shown) in the apparatus main body. The monitor 17 is provided for observing a signal of the CCD camera 6 as an image via an image signal processing device (not shown). The operation of the XY table 2, the motor 13, the zoom motor 15, and the laser beam emission timing of the laser oscillator are calculated and controlled by a control device (not shown) in the apparatus main body 1.

Next, laser processing using this embodiment will be described. FIG. 2 is a diagram showing a part of a workpiece 100 (an electronic circuit board in the present embodiment), a circuit pattern 101 that is pre-soldered, and a part of a lead wire 102 that is fixed to the circuit pattern 101 by soldering. . The pattern 101 has a shape in which the pattern width gradually increases toward the right in FIG.

A broken-line circle 103 and a broken-line circle 104
Indicates the state of the spot diameter of the laser beam changed according to the change in the pattern width when the workpiece 100 is moved in the direction of arrow A. Circuit pattern processing condition information of the workpiece 100 is input to a control device in the apparatus main body 1 in advance.

First, the workpiece 100 is set on the XY table 2, and a processing start switch (not shown) is turned on. XY table 2 based on processing condition information input in advance
Moves to the laser beam irradiation position, for example, the position of the circle 103 in FIG. 2, and irradiates the spot diameter indicated by the broken line of the circle 103. Then, as the workpiece 100 moves in the arrow A direction, for example, The spot diameter is changed according to the pattern width like the spot diameter indicated by the broken line of the circle 104.

When the spot diameter is increased in this manner, the zoom motor 15 is operated to change the focal length of the zoom lens 8 via the gear 16 and the focusing gear 14, thereby increasing the spot diameter. Drive to move table 10
By bringing the laser light emitting end of the optical fiber 9 closer to the zoom lens 8 through the lens, the enlarged spot diameter is focused.

This series of operations is continuously controlled by a control device in the apparatus main body 1 in accordance with a change in the width of the pattern 101. When the spot diameter is reduced, the spot diameter is reduced by the zoom lens 8 and the laser beam emitting end of the optical fiber 9 is moved away from the zoom lens 8 so that the reduced spot diameter is focused.

The laser beam emitted from the laser beam emitting end of the optical fiber 9 is reflected by the beam splitter 4 in the irradiation tube 7 in the direction of the workpiece 100 and passes through the objective lens 3 so that the workpiece 100 is reflected. After irradiation with a predetermined spot diameter, the light is reflected, transmitted through the beam splitter 4, and forms an image on the surface of the CCD camera 6 via the imaging lens 5. Signals from the CCD camera 6 are processed by an imaging signal processing device installed in the apparatus main body 1 and can be observed as an image on the monitor 17.

[0021]

As described above, the present invention has a control device for making the introduction means for introducing the laser beam into the irradiation tube movable and for controlling the movement of the introduction means. Even if the size of the laser beam is not constant, the spot diameter can be continuously enlarged and reduced without blurring the periphery of the irradiation spot of the laser beam. Since the spot diameter can be reduced without performing, efficient use is possible.

[Brief description of the drawings]

FIG. 1 is an overall view of a laser processing apparatus according to an embodiment of the present invention.

FIG. 2 is a partially enlarged view of a workpiece in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Apparatus main body 3 Objective lens 4 Beam splitter 5 Imaging lens 6 CCD camera 7 Irradiation cylinder 8 Zoom lens 9 Optical fiber 10 Moving stand 12 Rotation axis 13 Motor 15 Zoom motor

Claims (1)

[Claims] 1. A laser oscillator, an optical system for introducing a laser beam emitted from the laser oscillator and emitting the laser beam toward a workpiece, an introduction unit for introducing the laser beam into the optical system, and a processing state. Having an observation means for observing the optical system, wherein the optical axis of the introduction means coincides with the optical axis of the optical system, and the introduction means is fixed to a moving means movable along the optical axis. Characteristic laser processing equipment.