JP2003161907A - Laser beam diameter varying device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a laser beam diameter varying device which can vary the beam diameter of laser light while avoiding making the device large-sized. <P>SOLUTION: When line width X2 is set and varied, individual mirrors 15 to 18 are rotated to angles shown by broken lines in the figure, the angle of incidence of radiation laser light L2 on one parallel mirror 12 varies with the angle of rotation of the 1st and 2nd reflecting mirrors 15 and 16, and the laser light is reflected repeatedly twice between both parallel mirrors 12 and 12 and projected on the side of an optical axis adjusting reflecting means 14. That is, the optical path length from incidence on the gap between the couple of parallel mirrors 12 and 12 to projection becomes shorter in proportion to a decrease in reflection frequency as compared with the case that line width is set at X1. The diameter of the luminous flux of the radiation laser light L2 projected on the side of the optical axis adjusting reflecting means 14 becomes smaller corresponding to the shortening of the optical path length. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser beam diameter varying device for varying the beam diameter of laser light from a laser generator.

[0002]

2. Description of the Related Art For example, there is a laser marking device that utilizes laser light. This is equipped with a laser generating means for emitting a laser beam and a galvano scanner for scanning the irradiation point of the laser beam on the object to be printed by changing the direction of the laser beam, and print information such as characters to be printed. By driving and controlling the galvano scanner based on the above, the characters and the like are printed on the print target.

By the way, the above laser marking device is
For example, printing may be performed on various types of print targets such as different materials. Further, even for the same type of print target object, for example, characters with different line segment widths such as bold letters and thin letters may be printed. Therefore, it is necessary to change the beam diameter of the laser light according to the type or line width of the object to be printed.

Therefore, conventionally, for example, a collimator device having a concave lens and a convex lens is arranged in the optical path of the laser beam from the laser generating means toward the galvano scanner side.
Japanese Patent Laid-Open No. 2000-710 capable of changing the beam diameter of the laser beam to the print target by changing the distance between both lenses.
88 etc. More specifically, the laser light from the laser generating means passes through the concave lens and goes toward the convex lens as radiation light having a predetermined spread angle. Here, if the convex lens is moved away from the concave lens, the beam diameter of the laser light that passes through the convex lens and becomes parallel light increases. On the contrary, when the convex lens is brought closer to the concave lens side, the beam diameter of the laser light which passes through the convex lens and becomes parallel light becomes smaller.

[0005]

However, in the above-mentioned conventional structure, the lens distance between the concave lens and the convex lens is required according to the variable range of the beam diameter of the laser light. This means that the wider the variable range of the beam diameter, the larger the collimator device in the moving direction of the convex lens,
Consequently, it means that the entire laser marking device becomes large. In particular, in recent years, marking devices tend to be diversified, such as widening the variable range of the beam diameter, but like other devices, there is a strong demand for miniaturization, and there is a problem that both requirements cannot be satisfied. .

The present invention has been made in view of the above circumstances, and an object thereof is to provide a laser beam diameter varying device capable of changing the beam diameter of laser light while avoiding an increase in the size of the device. Where it is.

[0007]

In order to achieve the above object, the laser beam diameter varying device according to the invention of claim 1 is
A laser beam diameter varying device for changing the beam diameter of laser light emitted from a laser generator, comprising laser generating means for emitting non-parallel laser light and a pair of reflecting mirrors arranged to face each other. The laser light from the laser generating means is arranged to enter the reflecting surface of one of the pair of reflecting mirrors in a non-vertical direction, and the laser light is reflected between the reflecting mirrors. The laser light reflecting means for emitting, the incident angle changing means for changing the incident angle at which the laser light from the laser generating means is incident on the reflection mirror, and the laser light emitted from the laser light reflecting means are moved on a predetermined optical axis. It is characterized in that it is provided with an optical axis adjusting reflection means for reflecting the light so as to pass through.

A laser beam diameter varying device according to a second aspect of the invention is a laser beam diameter varying device for changing the beam diameter of a laser beam emitted from a laser generating device, the laser generating beam emitting a non-parallel laser beam. Means, comprising a pair of reflecting mirrors arranged to face each other, for any one of the reflecting surface of the pair of reflecting mirrors,
The laser light from the laser generating means is arranged so as to enter from a non-vertical direction, and the laser light reflecting means that reflects the laser light between the two reflecting mirrors and emits the laser light, and the relative reflecting surfaces of both reflecting surfaces of the pair of reflecting mirrors. It is characterized in that it is provided with a relative angle changing means for changing the angle and an optical axis adjusting reflecting means for reflecting the laser light emitted from the laser light reflecting means so as to pass along a predetermined optical axis.

The invention of claim 3 relates to claim 1 or claim 2.
In the laser beam diameter varying device described in (1), the optical axis adjusting reflecting means is composed of an optical axis adjusting mirror which is movable in parallel on a predetermined optical axis and is rotatable, and is emitted from the laser light reflecting means. The optical axis adjustment mirror is characterized in that the optical axis adjustment of the laser light is performed by rotating the optical axis adjustment mirror while moving the optical axis adjustment mirror in parallel so that the laser light enters substantially the center of rotation of the optical axis adjustment mirror.

The invention of claim 4 is claim 1 or claim 2.
In the laser beam diameter varying device described in (1), the optical axis adjusting reflecting means includes a first optical axis adjusting mirror which is rotatably provided and reflects the laser beam, and a first optical axis reflecting mirror which is rotatably provided. A second optical axis adjusting mirror for reflecting the reflected laser light is provided, and the first optical axis adjusting mirror is rotated so that the laser light from the laser light reflecting means is incident on the rotation center of the second optical axis adjusting mirror. It is characterized in that the second optical axis adjusting mirror is rotated so that the laser light from the first optical axis adjusting mirror is reflected on a predetermined optical axis while being moved.
It should be noted that a configuration that does not include the laser generating means is also conceivable as described below. A laser beam diameter varying device for changing the beam diameter of non-parallel laser light emitted from a laser generating means, comprising a pair of reflecting mirrors arranged so as to face each other. Laser light reflecting means arranged so that the laser light from the laser generating means is incident from a non-perpendicular direction to one of the reflecting surfaces, and the laser light is reflected and emitted between the two reflecting mirrors. An incident angle changing means for changing an incident angle of the laser light from the laser generating means incident on the reflection mirror, and a laser light emitted from the laser light reflecting means is reflected so as to pass on a predetermined optical axis. A device for varying a laser beam diameter, comprising: A laser beam diameter varying device for changing the beam diameter of the non-parallel laser light emitted from the laser generating means, comprising a pair of reflecting mirrors arranged so as to face each other. The laser light reflected from one of the mirrors is arranged so that the laser light from the laser generating means is incident in a non-vertical direction, and the laser light is reflected by the reflecting mirrors and emitted. Means, relative angle changing means for changing a relative angle between both reflecting surfaces of the pair of reflecting mirrors, and light for reflecting the laser light emitted from the laser light reflecting means so as to pass on a predetermined optical axis. A laser beam diameter varying device comprising an axis adjusting reflecting means.

[0011]

<Invention of Claims 1 and 2> The non-parallel laser light from the laser generating means is incident on the reflecting surface of one of the reflecting mirrors of the laser light reflecting means in a non-perpendicular direction. Then, the laser light is reflected and emitted between the pair of reflection mirrors, and is reflected by the optical axis adjusting reflection means so as to pass on a predetermined optical axis. Here, when it is desired to change the laser beam diameter, the incident angle changing means may change the incident angle at which the laser light from the laser generating means is incident on the reflecting mirror. According to the structure of claim 2, the relative angle changing means may change the relative angles of both reflecting surfaces of the pair of reflecting mirrors.
As a result, the optical path length of the laser light reflected and emitted in the laser light reflecting means can be changed, and thus the beam diameter of the laser light emitted from this device can be changed.

<Invention of Claim 3> According to the configuration of Claim 3, the laser light emitted from the laser light reflecting means is reflected at substantially the center of rotation of the optical axis adjusting mirror and passes through a predetermined optical axis. .
Here, even when the emitting direction of the laser light from the laser light reflecting means is changed by the operation of the incident angle changing means or the relative angle changing means, the optical axis adjusting mirror is rotated while being moved in parallel, so that the predetermined direction is always maintained. It can be reflected so that it passes along the optical axis.

<Invention of Claim 4> According to the configuration of Claim 4, the laser light emitted from the laser light reflecting means is the first laser light.
The light is reflected by the optical axis adjusting mirror, is incident on the rotation center of the second optical axis adjusting mirror, and is reflected so as to pass on a predetermined optical axis. Here, even when the emitting direction of the laser light from the laser light reflecting means is changed by the operation of the incident angle changing means or the relative angle changing means, the first and second optical axis adjusting mirrors are rotated accordingly. Thus, the light can be reflected so that it always passes along a predetermined optical axis.

[0014]

With such a structure, it is not necessary to secure the inter-lens distance according to the variable range of the beam diameter as in the conventional structure provided with the collimator device, and the laser can be downsized while the device is miniaturized. It is possible to change the beam diameter.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment> A first embodiment of the present invention will be described with reference to FIGS. FIG. 1 is an overall schematic diagram when a laser beam diameter varying device 10 according to claim 1 is applied to a laser marking device (corresponding to a “laser generator” according to claims 1 and 2). . This laser marking device includes a laser light source 20 that emits a laser beam, and a print target W through a converging lens 21 (for example, an fθ lens) that changes the direction of the laser beam.
The galvano scanner 22 that scans the irradiation point of the laser beam formed above and the CPU 23 as a control unit that controls the galvano scanner 22 are provided. Then, by driving and controlling the laser light source 20 and the galvano scanner 22 based on print information such as characters, figures, symbols to be printed (hereinafter referred to as “characters”), the characters and the like on the print target W are printed. Is printed.

Now, as shown in FIG. 1, a laser light source 20
A beam expander 24 for converting the laser light L1 from the laser light source 20 into a radiated light having a predetermined divergence angle (hereinafter referred to as "radiated laser light L2") in the optical path of the laser light emitted from the laser light source to the galvano scanner 22. A laser beam diameter varying device 10 and a collimator lens 25 for collimating laser light L2 emitted from the laser beam diameter varying device 10 into parallel light (hereinafter referred to as "parallel laser light L3") are provided. The laser beam diameter varying device 10 includes a pair of parallel mirrors 12 and 12 (corresponding to “laser light reflecting means” of the present invention) arranged to face each other in a substantially parallel manner, and the pair of parallel mirrors 12 and 12. An incident angle changing means 13 for changing the incident angle of the radiated laser beam L2 to one side (the parallel mirror 12 on the right side of the drawing in the figure) and an optical axis adjusting reflecting means 14 are provided.

Of these, the incident angle changing means 13 is provided with a first reflecting mirror 15 arranged to face the traveling direction of the radiated laser beam L2 having passed through the beam expander 24, and its first reflecting mirror 15.
The first reflection mirror 15 is arranged so as to face the reflection mirror 15.
A second reflecting mirror 16 for reflecting the reflected light from the second parallel mirror 12 to enter the reflecting surface of the one parallel mirror 12 in a direction not perpendicular to the reflecting surface. Each of the first and second reflecting mirrors 15 and 16 has, for example, a galvanometer (not shown) about an axis centering along a direction (the depth direction in the drawing in the figure) perpendicular to the traveling direction of the radiated laser beam L2. It is rotatably provided by a motor. The two reflecting mirrors 15 and 16 are driven and controlled based on a control signal from the CPU 23, and the incident angle of the radiated laser beam L2 on the reflecting surface of the one parallel mirror 12 can be changed.

Next, the optical axis adjusting / reflecting means 14 passes the emitted laser light L2 through the collimator lens 25 regardless of the emitting direction of the emitted laser light L2 from between the pair of parallel mirrors 12, 12 and the galvano scanner 22 side. It is for adjusting the optical axis direction by reflecting the light so as to pass through the optical axis (corresponding to the "predetermined optical axis" of the present invention, hereinafter referred to as "regular optical axis"). Therefore, in this embodiment,
The configuration according to the invention of claim 4 is applied. More specifically, the optical axis adjusting reflecting means 14 includes a pair of parallel mirrors 1.
The first optical axis adjusting mirror 17 is arranged to face the emission direction of the laser beam L2 emitted from the second and the second lasers 12, and the first optical axis adjusting mirror 17 is arranged to face the first optical axis adjusting mirror 17.
And a second optical axis adjusting mirror 18 for reflecting the radiated laser beam L2 reflected by the laser beam through the regular optical axis. These first and second optical axis adjusting mirrors are both laser light L2 emitted from between the pair of parallel mirrors 12 and 12.
Is provided so as to be rotatable by, for example, a galvano motor (not shown) about an axis along a direction perpendicular to the emission direction of (in the drawing, the depth direction of the paper surface).

Then, both the optical axis adjusting mirrors 17 and 18 are drive-controlled based on the control signal from the CPU 23, so that the radiated laser beam L2 from the pair of parallel mirrors 12 and 12 is always irrespective of the emitting direction. It can be reflected so that it passes through the regular optical axis. Then, the radiated laser beam L2 traveling along the regular optical axis is converted into a parallel laser beam L3 via the collimator lens 25 and is converted into a galvano scanner 22.
Leading to.

Next, the operation of this embodiment will be described with reference to the simplified diagram shown in FIG. The galvano scanner 22 is omitted in FIG. Further, the solid line portion shows the rotation positions of the mirrors 15 to 18 and the optical path of the radiated laser beam L2 when the line width X1 is set, and the broken line portion shows the line width X2 (<X1). Each mirror 15 ~
The rotational position of 18 and the optical path of the emitted laser light L2 are shown. First, a character or the like to be printed is set by a setting unit (not shown) (eg console). At this time, marking parameters such as the printing speed and the line width (the spot diameter size of the parallel laser beam L3 on the object W to be printed) are also set. Then, by the CPU 23, together with a plurality of coordinate data and ON / OFF control data of the laser light source 20 corresponding to the position on the print target object W based on the above-mentioned characters,
Spot diameter setting data corresponding to the set line width is generated.

Incidentally, the spot diameter setting data means the first and second reflecting mirrors 15 and 16 constituting the incident angle changing means 13 and the first constituting the optical axis adjusting reflecting means 14.
And the control data given to the galvano motors that rotate and drive the second optical axis adjusting mirrors 17 and 18, respectively. In the present embodiment, the control data is experimentally obtained for each of various line widths (spot diameter sizes) that can be changed by the setting unit, and stored in advance in a memory or the like not shown. Then, a control data group corresponding to the line width set by the setting unit is read by the CPU 23 and given to each of the galvanomotors, and each mirror 15 to 18 is rotated at an angle corresponding to the control data. Is done.

If the line width is set to X1, for example, the mirrors 15 to 18 are rotated by the angles shown by the solid lines in FIG. Then, the radiated laser beam L2 that has passed through the beam expander 24 is reflected between the first and second reflection mirrors 15 and 16, and the one parallel mirror 12 is reflected.
To the optical axis adjusting and reflecting means 14 side after repeating reflection four times. The emitted laser light L2
Is reflected by the first optical axis adjusting mirror 17 and is reflected by the rotation center of the second optical axis adjusting mirror 18, so that the emitted laser light L2 passes through the regular optical axis and the laser beam diameter varying device. It will be output from 10. Then, the collimator lens 25 forms the parallel laser beam L3 and the irradiation point having the spot diameter corresponding to the line width X1 is formed on the print target W through the converging lens 21.

When the line width is changed to X2 in the setting section, the mirrors 15 to 18 are rotated by the angle shown by the broken line in FIG. Then, the incident angle at which the radiated laser beam L2 enters one of the parallel mirrors 12 changes in accordance with the rotation angles of the first and second reflecting mirrors 15 and 16, and the two parallel mirrors 12 and 12 are reflected twice. The light is repeatedly emitted to the optical axis adjusting reflecting means 14 side. That is, as compared with the case where the line width X1 is set as described above, the optical path length until the light is incident between the pair of parallel mirrors 12 and exits is shortened by the number of times of reflection reduced, and accordingly the light The diameter of the luminous flux of the radiated laser beam L2 emitted to the side of the axis adjusting reflecting means 14 becomes small. Then, the emitted radiated laser beam L2 is also reflected by the first optical axis adjusting mirror 17 and is reflected by the rotation center of the second optical axis adjusting mirror 18, and thus the same light as when the line width X1 is set. The radiated laser beam L2 passing on the axis is emitted from the laser beam diameter varying device 10. As a result, the collimator lens 25 converts the collimated laser beam L3 into an irradiation point having a diameter corresponding to the line width X2 through the converging lens 21 on the object W to be printed.

With such a structure, it is not necessary to secure the distance between the lenses according to the variable range of the beam diameter as in the conventional structure provided with the collimator device, and the laser beam diameter can be reduced while the device is downsized. Can be made variable.

<Second Embodiment> FIGS. 3 and 4 show a second embodiment (corresponding to the invention of claim 2). The difference from the above embodiment is that instead of the configuration corresponding to the “incident angle changing means 13” in claim 1, a configuration corresponding to the “relative angle changing means” in claim 2 and optical axis adjustment are provided. The structure of the reflecting means is the same as the first embodiment in other points. Therefore, the same reference numerals as those of the first embodiment are given, duplicated explanations are omitted, and only different points will be explained next.

As shown in FIG. 3, a pair of parallel mirrors 3 is provided.
One of the 0 and 30 parallel mirrors 30 (a parallel mirror on the right side of the drawing in the figure) is provided so as to be tiltable about one end side by, for example, a galvano motor (not shown) to configure the "relative angle changing means". There is. Then, the laser light L2 emitted from the beam expander 24 is reflected by the fixed reflection mirror 31 arranged opposite to the traveling direction thereof, and is reflected by the reflection surface of the other parallel mirror 30 (the parallel mirror on the left side of the drawing in the figure). Incident from a non-vertical direction.

Further, the optical axis adjusting reflecting means can be moved in parallel along the regular optical axis by a slide mechanism (not shown), and in the emitting direction of the radiated laser beam L2 from the pair of parallel mirrors 30, 30. The optical axis adjusting mirror 32 is provided so as to be rotatable about a vertical axis center by, for example, a galvano motor (corresponding to the configuration according to claim 3). This optical axis adjusting mirror 32 is a CPU
Based on the control signal from 23, the parallel mirrors 30, 30
The laser light L2 emitted from the space is controlled to rotate while moving in parallel to a position opposed to various emission directions and to reflect the emitted laser light L2 on the regular optical axis at the center of rotation.

Next, the operation of this embodiment will be described with reference to the simplified diagram shown in FIG. The galvano scanner 22 is omitted in FIG. Further, the solid line portion shows the rotation positions of the mirrors 30 and 32 and the optical path of the radiated laser beam L2 when the line width X1 is set, and the broken line portion when the line width X2 (<X1) is set. Each mirror 30,
The rotation position of 32 and the optical path of the emitted laser beam L2 are shown.

For example, when the line width is set to X1, the mirrors 30 and 32 are rotated by the angle shown by the solid line in FIG. 4, and the radiated laser beam L2 reflected by the fixed reflection mirror 31.
Is incident on one of the parallel mirrors 30 and is reflected four times, for example, and is reflected at the center of rotation of the optical axis adjusting mirror 32.
Therefore, the emitted laser beam L2 is output from the laser beam diameter varying device 10 after passing through the regular optical axis.
Then, the collimator lens 25 forms the parallel laser beam L3 and the irradiation point having the spot diameter corresponding to the line width X1 is formed on the print target W through the converging lens 21.

Here, when the line width setting is changed to X2, one parallel mirror 30 as shown by the broken line in FIG.
Tilts in a direction away from the other parallel mirror 30, and the relative angle between the two parallel mirrors 30, 30 becomes wider. Then, the radiated laser beam L2 reflected by the fixed reflection mirror 31 is repeatedly reflected once between the parallel mirrors 30 and 30 to be emitted. That is, the pair of parallel mirrors 3 is reduced by the number of reflections compared to the case where the line width X1 is set as described above.
The optical path length until the light enters and exits 0, 30 is shortened, and the diameter of the luminous flux of the radiated laser light L2 emitted to the optical axis adjusting and reflecting means side is accordingly reduced.

The optical axis adjusting mirror 32 is the CPU 23.
On the basis of the control signal from, the laser beam is rotated while being moved in parallel to the position facing the emission direction of the radiated laser beam L2. As a result, the emitted laser light L2 is reflected at the center of rotation of the optical axis adjusting mirror 32, so that the laser light L2 passing through the regular optical axis, which is the same as when the line width X1 is set, is laser light. It is output from the beam diameter varying device 10. As a result, the collimator lens 25 converts the collimated laser beam L3 into the parallel lens beam L3, and the line width X2 passes through the converging lens 21.
An irradiation point having a diameter corresponding to is formed on the print target object W.

<Third Embodiment> In the first embodiment,
The first and second reflecting mirrors 15 and 16 are rotated to change the incident angle of the radiated laser beam L2 to one of the parallel mirrors 12. However, in the present embodiment, as shown in FIG. The incident angle is changed by rotating the light source 20 and the beam expander 24.

<Fourth Embodiment> In the first embodiment, the laser beam diameter varying device 10 is configured to output the emitted laser light L2 in the same direction as the emitting direction of the laser light source 20, but the invention is not limited to this. For example, as shown in FIG. 6, the arrangement direction of the first and second optical axis adjusting mirrors 17 and 18 is changed in the configuration of the first embodiment so as to face the emission direction of the laser light source 20. Direction laser light L2
May be output from the laser beam diameter varying device 10.

In the first embodiment, the incident angle changing means 13 has the first and second reflecting mirrors 15 and 16, but the present invention is not limited to this. As shown in FIG. The reflection mirror 40 is rotated to drive the parallel mirror 1.
The incident angle of the radiated laser beam L2 with respect to one of the reflecting surfaces 2 and 12 may be changed.

<Fifth Embodiment> In the second embodiment, the laser beam diameter varying device 10 is configured to output the radiated laser beam L2 in the same direction as the emission direction of the laser light source 20, but not limited to this. For example, as shown in FIG. 7, the arrangement of the optical axis adjusting mirror 32 is changed in the configuration of the second embodiment so that the laser light L2 is emitted in a direction opposite to the emission direction of the laser light source 20. The configuration may be such that the beam diameter varying device 10 outputs the beam.

<Other Embodiments> The present invention is not limited to the above-described embodiments. For example, the embodiments described below are also included in the technical scope of the present invention.
Other than the following, various modifications can be made without departing from the scope of the invention. (1) In each of the above-described embodiments, the beam expander 24 is provided in order to make the laser light L1 from the laser light source 20 radiate light with a predetermined divergence angle, but it is not necessarily an essential configuration. This is because the laser light from the laser light source 20 is not completely parallel light but radiated light that spreads to some extent. Therefore, even if the beam expander 24 is not provided, the laser beam from the laser light source 20 is changed to the laser beam diameter varying device 10 described above.
It is possible to change the diameter size of the light flux via. However, when the beam expander 24 is provided as in each of the above-described embodiments, the laser light can be more reliably converted into the emitted light, and the effect of the present invention can be more reliably obtained.

(2) In each of the above embodiments, the laser light source 20 is formed by using the concave lens which is the beam expander 24.
Although the laser light from the laser is emitted as the emitted light, the laser light entering the laser beam variable device may be any non-parallel light, for example, the laser light converged by using a convex lens is incident. May be.

(3) Each of the above embodiments has been described by taking the case of being applied to a laser marking device as an example, but the present invention is not limited to this. For example, a measuring device such as a laser displacement meter or a detecting device such as a photoelectric sensor. But it's okay. This is because the beam diameter of the laser light may differ depending on the size and material of the object.

(4) In each of the above embodiments, each mirror (1
5-18, 30, 32, 40, etc.) is C as a control means.
Although it is configured to be automatically driven based on the control signal of the PU 23, the present invention is not limited to this, and a configuration in which an operator manually rotates and moves all or some of the mirrors may be set. .

(5) In the first embodiment described above, the pair of parallel mirrors 12 and 12 are arranged in parallel, but the present invention is not limited to this and may be arranged non-parallel to each other.

(6) In the second embodiment described above, the configuration in which one of the parallel mirrors 30 is tilted has been described, but the present invention is not limited to this. For example, the configuration in which the other parallel mirror 30 or both parallel mirrors 30, 30 is tilted. May be

[Brief description of drawings]

FIG. 1 is an overall schematic view of a laser marking device according to a first embodiment of the present invention.

FIG. 2 is a simplified diagram showing each optical path of laser light accompanying each mirror drive.

FIG. 3 is an overall schematic view of a laser marking device according to a second embodiment.

FIG. 4 is a simplified diagram showing each optical path of laser light accompanying each mirror drive and the like.

FIG. 5 is a schematic diagram of a laser beam diameter varying device according to a third embodiment.

FIG. 6 is a schematic diagram of a laser beam diameter varying device according to a fourth embodiment.

FIG. 7 is a schematic diagram of a laser beam diameter varying device according to a fifth embodiment.

[Explanation of symbols]

10 ... Laser beam diameter variable device 12,30 ... Parallel mirror 13 ... Incident angle changing means 14 ... Optical axis adjusting reflection means 15 ... 1st reflective mirror 16 ... Second reflective mirror 17 ... First optical axis adjusting mirror 18 ... Second optical axis adjusting mirror 20 ... Laser light source 23 ... CPU 31 ... Fixed reflection mirror 32 ... Optical axis adjustment mirror L2 ... Emitted laser light W ... Printed object

Claims (4)

[Claims] 1. A laser beam diameter varying device for changing the beam diameter of laser light emitted from a laser generator, comprising: laser generating means for emitting non-parallel laser light; A reflecting mirror is provided, and a laser beam from the laser generating means is arranged so as to be incident on a reflecting surface of one of the pair of reflecting mirrors in a non-vertical direction. Laser light reflecting means for reflecting and emitting between the reflecting mirrors, incident angle changing means for changing an incident angle of the laser light from the laser generating means entering the reflecting mirror, and laser light reflecting means for emitting. A laser beam diameter varying device, comprising: an optical axis adjusting reflection means for reflecting laser light so as to pass on a predetermined optical axis. 2. A laser beam diameter varying device for changing the beam diameter of laser light emitted from a laser generator, comprising laser generating means for emitting non-parallel laser light, and a pair of laser generating means arranged opposite to each other. A reflecting mirror is provided, and a laser beam from the laser generating means is arranged so as to be incident on a reflecting surface of one of the pair of reflecting mirrors in a non-vertical direction. Laser light reflecting means for reflecting and emitting between the reflecting mirrors, relative angle changing means for changing the relative angle of both reflecting surfaces of the pair of reflecting mirrors, and laser light emitted from the laser light reflecting means, A laser beam diameter varying device, comprising: an optical axis adjusting reflection means for reflecting the light so as to pass along a predetermined optical axis. 3. The laser beam emitted from the laser beam reflecting means is constituted by an optical axis adjusting mirror which is capable of moving in parallel on the predetermined optical axis and is rotatable. 2. The optical axis of the laser beam is adjusted by rotating the optical axis adjusting mirror while moving the optical axis adjusting mirror in parallel so that the light enters the optical axis adjusting mirror substantially at the center of rotation of the optical axis adjusting mirror. Two
The laser beam diameter changing device described in. 4. The optical axis adjusting / reflecting means is a rotatably provided first optical axis adjusting mirror for reflecting the laser beam, and a rotatably provided laser for reflecting the first optical axis reflecting mirror. A second optical axis adjusting mirror for reflecting the light, and rotating the first optical axis adjusting mirror so that the laser light from the laser light reflecting means is incident on the rotation center of the second optical axis adjusting mirror. The first optical axis adjusting mirror is rotated, and the second optical axis adjusting mirror is rotated so as to reflect the laser light from the first optical axis adjusting mirror on the predetermined optical axis. The laser beam diameter varying device described.