JPH08148740A - Solid-state laser masking device - Google Patents

Abstract

PURPOSE: To control the magnitude of a pulse being the intensity of a solid-state laser beam easily by controlling the control part so that the beam intensity to be emitted from a semiconductor laser may by smaller than a normal value, until an initial pulse of a solid-state laser beam is oscillated. CONSTITUTION: A control part 5 controls the laser beam intensity for lighting, lights-out, and excitation of an LDA 12 through the medium of a power device 4, and excites the atoms of YAG rod 1. At this time, it becomes possible for an LDA 12 to change exciting laser beam intensity to strong or weak, or to perform high-speed switching. Consequently, it becomes possible to freely adjust the quantity of excitation energy to be accumulated in the YAG rod 1. Accordingly, it becomes possible to control the magnitude of a pulse being the intensity of a solid-state laser beam easily.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state laser marking device, and more particularly to a semiconductor laser diode (hereinafter LD).
A solid-state laser marking device by LD excitation for controlling an initial pulse when a solid-state laser light is oscillated using a semiconducting laser.

[0002]

2. Description of the Related Art A laser is a device for amplifying and oscillating light utilizing stimulated emission of radiation by atoms and molecules. Therefore, it is necessary to increase the number of atoms in a high energy state and increase the stimulated emission rather than the absorption of light by photoexciting a substance in which many atoms are gathered. Then, in order to obtain a solid-state laser light having a higher light intensity and a high directivity,
There is a need for a resonator that traps light and amplifies the excitation energy of the light.

Therefore, as shown in FIG. 4, the conventional solid-state laser marking apparatus is for optically exciting a cylindrical YAG rod 1 which is one of the laser media having excellent optical characteristics and the atoms of the YAG rod 1. The excitation lamp 2 has an elliptical cross section, and is housed in parallel with each other at each focal point in the cavity 3 whose inner wall is a mirror surface. The excitation lamp 2 is connected to the power supply device 4 whose power supply timing is controlled by the control unit 5, and is turned on and off.

A total reflection mirror 6 for totally reflecting light is arranged at one end of the YAG rod 1 at a predetermined distance from the end face of the YAG rod 1, and at the other end thereof. A Q switch 7 that diffracts the light emitted from the YAG rod 1 is arranged at a predetermined distance from the end surface of the YAG rod 1, and the YAG rod 1 and the Q switch 7 are connected to each other. A semitransparent output mirror 8 that transmits only a predetermined solid laser beam is arranged on the extension line.

Then, a voltage Q is applied to the Q switch 7 in order to operate the Q switch 7 at a specific frequency.
Switch drive 9 is connected, and further this Q
The switch drive 9 is controlled by the controller 5 in terms of the amount of voltage applied to the Q switch 7 and its timing. Therefore, based on this specific frequency, the Q switch 7 is turned on while the YAG rod 1 accumulates excitation energy, and diffracts the light emitted when the excited atoms of the YAG rod 1 return to the ground state. When the YAG rod 1 outputs a predetermined solid-state laser light, the YAG rod 1 is turned off to allow the solid-state laser light to pass therethrough. Then, at the destination of the solid-state laser light that has passed through the output mirror 8, the workpiece 11
A scanner unit 10 having two movable mirrors and the like (not shown) for scanning the solid-state laser light in the X and Y directions for marking is provided.

The operation of the conventional solid-state laser marking device having such a structure is as follows.
Controls the power supply device 4 to cause the excitation lamp 2 to emit light. At this time, since the light of the excitation lamp 2 travels radially, some of them directly travel toward the YAG rod 1 and some of them collide toward the inner wall of the cavity 3. Regarding the light that collides with the inner wall of the cavity 3 and is reflected, the cavity 3 is formed in an elliptical shape in cross section, and the excitation lamp 2 and the YAG rod 1 are arranged at respective focal points of the elliptical shape of the cavity 3. Therefore, all will be concentrated on the YAG rod 1. Then, as shown in FIG. 3, the excitation energy in the YAG rod 1 increases in proportion to the irradiation time by the excitation lamp 2 and accumulates the excitation energy capable of oscillating the solid-state laser light with the passage of time, and Saturation is reached through the state of accumulating the excitation energy required to emit a stationary pulse. The atoms thus excited into the high-energy state emit the energy emitted when returning to the original ground state as light. These lights are emitted by spontaneous emission, and when spontaneous emission light emitted in the axial direction of the YAG rod 1 forms a resonance state in which phases are aligned, stimulated emission is caused. As a result, the light intensity is increased and laser light is oscillated. Therefore, as long as the YAG rod 1 does not accumulate enough excitation energy to oscillate a predetermined solid-state laser beam, the Q
The switch 7 is turned on to diffract the light traveling straight in the axial direction to increase the loss of the Q switch 7 (also referred to as the loss in the resonator) and prevent it from passing through the output mirror 8. Then, when the YAG rod 1 is continuously irradiated with the excitation lamp 2 and sufficient excitation energy for oscillating a predetermined solid-state laser beam is accumulated in the YAG rod 1, the Q switch 7 is turned off. The loss of the Q switch 7 is set to 0, and the light traveling in the axial direction is passed through the output mirror 8 as it is without being diffracted, and is output as solid-state laser light at once.

At this time, the frequency at which the Q switch 7 is turned on and off is usually set to several tens of KHz or less, which is the excitation energy required to oscillate a stationary pulse as shown in FIG. The Q switch 7 is operated by the voltage operation of the Q switch drive 9.

On the other hand, the solid-state laser light that has passed through the output mirror 8 enters the scanner unit 10 as it is, and the traveling direction of the workpiece 11 is changed by two movable mirrors (not shown) in the scanner unit 10. The workpiece 11 is marked by changing the direction and focusing the laser light through a lens (not shown).

Next, timing charts relating to the solid-state laser light of such a conventional solid-state laser marking device are shown in FIGS. 5 and 6 (a) to (c).

In FIG. 5, the horizontal axis represents time (a), (b) and (c), the vertical axis represents (a) the light intensity of the excitation lamp 2, and (b) the Q switch 7.
And (c) shows the intensity of the solid-state laser light, that is, the pulse size of the solid-state laser light.

As shown in (a), since the conventionally used excitation lamp 2 cannot control the light intensity, the atoms of the YAG rod 1 are always excited. Therefore, the amount of excitation energy accumulated by exciting atoms cannot be controlled, and the amount of accumulated energy in the YAG rod 1 increases with the passage of time. Finally, as shown in FIG. 3, the accumulated amount of the excitation energy exceeds the steady-state accumulated amount and becomes saturated.

Therefore, as shown in (b) and (c), in order to start marking on the workpiece 11, the Q switch 7 is turned off and the loss of the Q switch 7 is reduced to zero.
Then, if the excitation energy accumulated up to that point is released all at once as solid-state laser light, the initial pulse of the solid-state laser light immediately after the start of output becomes larger than the steady pulse. Since the magnitude of the pulse of this solid-state laser light directly affects the marking depth of the workpiece 11,
The marking with the initial pulse having a large pulse is deeper than the marking with the steady pulse, and there is a problem that a marking like a punch is made at the starting position of the marking.

In order to solve this problem, as shown in (a), (b) and (c) of FIG. 6, the excitation energy accumulated up to the start of marking is not released all at once, but The control unit 5 controls the Q switch 7 so that the amount of excitation energy emitted becomes equal to the amount of excitation energy emitted during steady operation several times from the start of marking.
It was thought to control. By controlling the Q switch 7 in this way, the magnitude of the initial pulse of the solid-state laser light is made closer to the magnitude of the steady pulse, and the workpiece 11 is marked with a constant marking depth.

[0014]

However, the control of the Q switch 7 by the control unit 5 as described above is a control which is quite difficult in reality. Normally, the pulse size of the solid-state laser light is determined by the excitation energy and the driving frequency of the Q switch 7. Therefore, if the relationship of the accumulated amount of the excitation energy with respect to the passage of time is known, the Q switch can be used. The drive frequency of 7 may be controlled to be constant. However, during the control at the beginning of the above-mentioned marking, the amount of excitation energy accumulated depends on the amount of excitation energy released last time, that is, the driving frequency of the Q switch 7, and the accumulation time thereafter. Will vary depending on whether or not has passed. Therefore, the control of the Q switch 7 must be changed for each condition, which is theoretically possible, but actually difficult control.

On the other hand, by controlling the turning on / off of the excitation lamp 2 that excites the YAG rod 1, rather than controlling the amount of energy released by the Q switch 7, the amount of accumulated excitation energy is controlled. It is also conceivable to control the initial pulse by controlling.

However, since the time required to store the excitation energy required to oscillate the solid-state laser light in the YAG rod 1 is usually about several hundreds of μs, the excitation lamp 2 can be operated at a high speed to cope with this speed. It is impossible to turn on or turn off the light by, and further, there is a drawback that the life of the excitation lamp 2 is shortened if control is performed such that lighting and turning off are repeated.

Therefore, the present invention provides a solid-state laser marking device that overcomes the problems of the conventional ones described above, facilitates oscillation control of the initial pulse of the solid-state laser light, and improves the marking finish. The purpose is to do.

[0018]

In order to achieve the above-mentioned object, a solid-state laser marking device according to the present invention comprises:
A solid-state laser medium that stores pumping energy inside by receiving light, a semiconductor laser that irradiates the laser medium with laser light for pumping, and a solid-state laser beam that is arranged in the output direction of the solid-state laser beam from the laser medium and is emitted from the laser medium. A Q switch that selectively diffracts the generated light according to the amount of excitation energy accumulated in the laser medium, and a Q switch that is arranged in the traveling direction of the light passing through the Q switch and selectively reflects or passes the light. An output mirror, a total reflection mirror that is arranged in a direction opposite to the output direction of the solid-state laser light and totally reflects the light, a scanner unit that advances the solid-state laser light that has passed through the output mirror toward a workpiece, and the semiconductor In a solid-state laser marking device having a light intensity of laser light for exciting a laser and a control unit for controlling switching of the Q switch, Parts are characterized by controlling the intensity of light emitted from the semiconductor laser to the initial pulse of a solid laser beam is oscillated so as to be smaller than the steady state.

[0019]

In the solid-state laser marking apparatus of the present invention, the control section controls the semiconductor laser to adjust the light intensity of the exciting laser light to excite the laser medium, and at the same time, to control the operation of the Q switch. It diffracts the spontaneous emission of light until the excitation energy is stored in the laser medium. Then, the diffracted light is reflected by the output mirror disposed ahead of it and returned to the direction of the laser medium. On the other hand, the light emitted in the direction opposite to the output direction is returned to the laser medium by the total reflection mirror. In this way, after a lapse of a predetermined time, necessary excitation energy is accumulated in the laser medium, and this excitation energy is oscillated as solid-state laser light. At this time, the control unit turns off the Q switch to allow the solid-state laser light to pass through in the output direction without being diffracted, and also allows the output mirror to pass therethrough to enter the scanner unit. Then, the focus and the traveling direction of the solid-state laser light are adjusted via this scanner unit to mark the workpiece.

Therefore, since the amount of excitation energy accumulated in the laser medium can be adjusted by the control unit, the control unit controls the semiconductor laser until the initial pulse of the solid-state laser light oscillated at the start of marking is output. By controlling the light intensity of the excitation laser beam to be small, the amount of excitation energy accumulated in the laser medium is adjusted so that the initial pulse is output with a magnitude equal to that of the stationary pulse, so that highly accurate marking can be performed. To

[0021]

The present invention will be described below with reference to the embodiments shown in the drawings. It should be noted that the same components as those of the conventional one described above are denoted by the same reference numerals in the drawings, and description thereof is omitted.

FIG. 1 shows a schematic configuration diagram of a main part of a solid-state laser marking device by LD excitation as an embodiment of the present invention.

In the solid-state laser marking apparatus of this embodiment, a cylindrical YAG rod 1 which is one of the laser media having excellent optical characteristics, and side pumping for directly irradiating the YAG rod 1 with the excitation laser from the side of the YAG rod 1 are used. A semiconductor laser diode array 12 (hereinafter abbreviated as LDA 12) that optically excites the atoms of the YAG rod 1 by the method is provided. The LDA 12 is connected to the power supply device 4 whose power supply is controlled by the control unit 5, and is capable of high-speed switching capable of switching between lighting and extinguishing at high speed. It has almost no adverse effects.

A total reflection mirror 6 for totally reflecting light is arranged at one end of the YAG rod 1 at a predetermined distance from the end face of the YAG rod 1, and at the other end thereof. A Q switch 7 that diffracts the light emitted from the YAG rod 1 is arranged at a predetermined distance from the end surface of the YAG rod 1, and the YAG rod 1 and the Q switch 7 are connected to each other. A semitransparent output mirror 8 that transmits only a predetermined solid laser beam is arranged on the extension line. Then, the Q switch 7
A Q switch drive 9 for supplying a voltage to operate the switch 7 at a specific frequency is connected, and further,
The Q switch drive 9 is controlled by the control unit 5 to the Q
The amount of voltage applied to the switch 7 and its timing are controlled. Therefore, based on this specific frequency, the Q switch 7 is turned on while the YAG rod 1 accumulates the excitation energy and diffracts the light emitted when the excited atoms of the YAG rod 1 return to the ground state. Then, it is reflected by the output mirror 8 so as not to be output, and is turned off when the YAG rod 1 outputs a predetermined solid-state laser beam. At the destination of the solid-state laser light that has passed through the output mirror 8, there are two movable mirrors (not shown) that scan the solid-state laser light in the X and Y directions for marking the workpiece 11. A scanner unit 10 is provided.

Next, the operation of this embodiment will be described.

In the solid-state laser marking apparatus using LD excitation according to this embodiment, the control unit 5 controls the turning on / off of the LDA 12 and the excitation laser light intensity via the power supply unit 4, and the atoms of the YAG rod 1 are controlled. Excite. At this time, since the LDA 12 can change the intensity of the excitation laser light to be strong or weak and can perform high-speed switching, the amount of excitation energy accumulated in the YAG rod 1 can be freely adjusted.

Therefore, until the marking is started, the laser light intensity for excitation of the LDA 12 is reduced so that the excitation energy is not accumulated too much as shown in FIG. 2 (a). Then, when the amount of excitation energy required to oscillate the solid-state laser light is accumulated, it oscillates as the solid-state laser light, and the controller 5 turns off the Q switch 7 via the Q switch drive 9. The solid-state laser light is output at once without being diffracted. Then, the solid-state laser light is emitted from the output mirror 8
And passes through to enter the scanner unit 10 disposed ahead of it. In the scanner unit 10, a movable mirror (not shown) controls the solid-state laser light so as to accurately travel toward the workpiece 11 to start marking.

The magnitude of the initial pulse when the first solid-state laser light is oscillated immediately after the start of marking is accumulated in the YAG rod 1 by the control unit 5 controlling the intensity of the exciting laser light of the LDA 12. Since the amount of excitation energy is adjusted so as to be the accumulation amount in the steady state shown in FIG. 3, the magnitude is the same as the magnitude of the steady pulse as shown in (b) and (c) of FIG. In the subsequent marking, since the on / off switching of the Q switch 7 is controlled at a constant drive frequency, the LDA 12
The laser light intensity for excitation by the excitation may be applied at a steady light intensity.

Then, in order to move to the next marking position in the middle of the marking, when the output of the solid-state laser beam is temporarily stopped and is output again after the movement, it is excited in the YAG rod 1 with the passage of time. The LDA1 is again used to prevent energy from being stored to saturation.
The light intensity of 2 is reduced, the amount of excitation energy accumulated in the YAG rod 1 is adjusted, and the magnitude of the pulse of the solid-state laser light to be output is controlled.

Therefore, according to the configuration of this embodiment, the control unit 5 controls the intensity of the laser light for excitation of the LDA 12 to adjust the amount of accumulated excitation energy in the YAG rod 1, Since the magnitude of the pulse, which is the intensity of the solid-state laser light, can be easily controlled, a deep marking mark such as a punch mark generated on the workpiece 11 due to the initial pulse is not generated.

The present invention is not limited to the above embodiment, but can be modified as necessary.

For example, the LDA 12 described above is
Although the so-called side pumping method is arranged laterally with respect to the AG rod 1, this may also be used as an end pumping method in which the excitation laser light is incident from the direction of the end surface of the YAG rod 1. Good.

The solid-state laser medium is not limited to YAG,
Ruby, glass, YLF, or the like may be used, and a quadrangular prism or slab shape other than the cylindrical shape may be used.

[0034]

As described above, according to the solid-state laser marking device of the present invention, the controller controls the intensity of the laser light for exciting LDA, so that the intensity of the pulse, which is the intensity of the solid-state laser light, can be easily adjusted. Can be controlled.

Therefore, since the initial pulse is larger than the steady pulse, a deep marking mark such as a punch mark generated on the workpiece is not generated, and it is possible to perform marking with high accuracy and excellent finish.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a solid-state laser marking device according to an embodiment of the present invention.

FIG. 2 is a timing chart regarding (a) excitation laser light intensity, (b) Q switch loss, and (c) solid laser pulse size in the solid-state laser marking device according to the embodiment of the present invention.

FIG. 3 is a diagram showing the relationship between the amount of excitation energy accumulated in the laser medium and the optical excitation time.

FIG. 4 is a configuration diagram of a main part of a conventional solid-state laser marking device.

FIG. 5: (a) Light intensity of an excitation lamp, (b) Q switch loss in a conventional solid-state laser marking device,
And (c) Respective timing charts regarding the pulse size of the solid-state laser light

FIG. 6 (a) Light intensity of an excitation lamp, (b) Q switch loss in another conventional solid-state laser marking device,
And (c) Respective timing charts regarding the pulse size of the solid-state laser light

[Explanation of symbols]

 1 YAG rod 2 Excitation lamp 3 Cavity 4 Power supply unit 5 Control unit 6 Total reflection mirror 7 Q switch 8 Output mirror 9 Q switch drive 10 Scanner unit 12 Semiconductor laser diode array (LDA)

[Procedure amendment]

[Submission date] December 26, 1995

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] Full text

[Correction method] Change

[Correction content]

[Document name] Statement

Title: Solid-state laser marking device

[Claims]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solid-state laser marking device, and more particularly to a semiconductor laser diode (hereinafter LD).
Solid-state laser medium by using semiconductors lasers omitted) such as
The present invention relates to a solid-state laser marking device by LD excitation for controlling an initial pulse when a laser beam is oscillated by exciting a quality .

[0002]

BACKGROUND ART Laser refers to amplification of light using stimulated emission of radiation by atoms and molecules. Therefore, high energy can be obtained by photoexciting a substance in which many atoms are gathered.
The number of atoms in the -state must be increased to increase the stimulated emission rather than the absorption of light. Then, further the light intensity is strong, in order to obtain high directivity solid-state laser light, it is necessary resonators confine light to amplify the error Nerugi over light.

Therefore, as shown in FIG. 4, a conventional solid-state laser marking device has a cylindrical YAG rod 1 which is one of the solid-state laser media having excellent optical characteristics and the YAG rod 1.
An excitation lamp 2 for optically exciting the atoms of the rod 1 has an elliptical cross section, and is housed in parallel with each other at each focal position in the cavity 3 whose inner wall is a mirror surface .
Excitation lamp 2, the timing of the power supply by the control unit 5
Is connected to the power supply device 4 that is controlled, and is turned on and off.

[0004] Then, at one end of the Y AG rod 1 Y A
A total reflection mirror 6 that totally reflects light is arranged at a predetermined distance from the end surface of the G rod 1, and the other end side thereof is provided.
Y A A predetermined distance from the end surface of the rod 1 Y A
G and Q-switch 7 for diffracting light emitted from the rod 1 is arranged, Y to further AG rod 1 and the Q-switch 7
A semi-transmissive output mirror 8 that transmits a part of a predetermined solid-state laser beam is arranged on an extension line connecting the and.

[0007], Q is a switch 7 which is Q-switch drive 9 for applying a voltage is connected to actuate the Q-switch 7 at a specific frequency, In addition, the Q-switch drive 9 are shorted with a control section 5 The amount of voltage applied to the Q switch 7 and its timing are controlled. Therefore , Q
Switch 7 is turned on based on this specific frequency
Rutoki accumulates Y AG rod 1 Gae Nerugi chromatography, Y AG
When the excited atoms of the rod 1 diffract the light emitted when returning to the ground state and the Q switch 7 is turned off, the YAG rod 1
The solid-state laser light from the total reflection mirror 6 and the output mirror 8
Between the output mirror 8 and the solid-state laser light.
I will be forced. Then, the progress destination of the solid-state laser light passing through the output mirror 8 having a workpiece 11 the solid-state laser light for marking X, like two movable mirror for scanning in the Y direction (not shown) A scanner unit 10 is provided.

[0006] the action of a conventional solid laser marking apparatus having a configuration such as this, first, control section 5 power supplies 4
Control to the emit excitation lamp 2. Light having an excitation lamp 2 at this time is to progress radially, as proceeding directly toward the Y AG rod 1, there is to that collide against the inner wall of the key Yabiti 3. This cavity 3
The light reflected by colliding with the inner wall of, key Yabiti 3 is formed in an elliptical cross-sectional shape, or One excitation lamp 2 and Y
Since the AG rods 1 are arranged at the respective elliptical focal points of the cavity 3, they are all concentrated on the YAG rod 1. Then, as shown in FIG. 3, d Nerugi chromatography in Y AG rod 1 in proportion to the irradiation time by the excitation lamp 2 increases, it can oscillate a solid laser beam over time Rue <br/> It reached Nerugi Reberu, subsequently through the steady pulse state reaches saturation state. Such excited by high energy form <br/> on purpose since atoms to emit <br/> energy that is released when returning to the original ground state as light. These lights are emission by spontaneous emission, these light sac Chi Y AG rod 1
When spontaneous resonance light emitted in the axial direction forms a resonance state in which the phases are aligned, stimulated emission is caused by this, and the light intensity is increased to oscillate laser light . The Q switch 7 should be turned on to diffract the light traveling straight in the axial direction to increase the loss of the Q switch 7 (also referred to as the loss in the resonator) so as not to cause stimulated emission.
And increase the energy density. Their to, after sufficient error Nerugi over to continue irradiation with Y AG rod 1 to the excitation lamp 2 to oscillate the predetermined solid-state laser beam are accumulated in the Y AG rod 1, turns off the Q-switch 7 to passed through the or or output mirror 8 without diffracting the light coming advanced axially by the loss of Q-switch 7 to 0 is outputted as a once solid state laser light.

[0007] The frequency of Q switch 7 is switched on and off at this time is usually several 10 k Hz or less, e Nerugi over required for this steady pulse as shown in FIG. 3 is oscillated There is a frequency that can secure the time until the accumulated, a voltage operation of the Q-switch drive 9
Q switch 7 operates.

On the other hand, the solid-state laser light that has passed through the output mirror 8 of the foregoing, and incident on the or mass scanner unit 10, the workpiece traveling direction by two movable mirrors (not shown) in the scanner unit 10 The workpiece 11 is marked by changing the direction of the laser beam 11 and condensing the laser light through a lens (not shown).

Next, timing charts relating to the solid-state laser light of such a conventional solid-state laser marking device are shown in FIGS. 5 and 6 (a) to (c).

In FIG. 5, the horizontal axis represents time (a), (b) and (c), the vertical axis represents (a) the light intensity of the excitation lamp 2, and (b) the Q switch 7.
And (c) shows the intensity of the solid-state laser light, that is, the pulse size of the solid-state laser light.

[0011] As shown in FIG. 5 (a), since the excitation lamp 2 that is conventionally used it is impossible to control the light intensity, atoms of Y AG rod 1 is constantly excited. Therefore, the amount of accumulated Rue <br/> Nerugi over by exciting atoms also will not be able to control the accumulated energy quantity of YAG rod 1 increases with time. And, finally, as shown in FIG. 3, the amount of accumulated error Nerugi over exceeds the accumulated amount in the steady state is falling back to the saturation level.

Therefore, as shown in FIGS. 5B and 5C, in order to start marking on the workpiece 11 , Q
Turn off switch 7 and set Q switch 7 loss to 0,
When it until accumulated error Nerugi over a stretch release as a solid laser beam, initial pulse of the output immediately after the start of the solid-state laser light, becomes larger than the steady pulse. Then, which directly affects the marking depth of the solid laser beam pulse magnitude pressurized Engineering object 11, marked by a large initial pulse of the pulse is deeper than the marking with a steady pulse, the starting position of the marking Had a problem of making punch marks.

[0013] To solve this problem, in FIG. 6 (a), (b) and (c), the instead of releasing all the error Nerugi over accumulated by the time marking the start at a time , the control unit 5, to control the Q-switch 7 so that Enel <br/> formate over emissions and the same amount in the steady state the release of Rie Nerugi over cotton several times from the time of marking the start it was thought. Then, by controlling the Q switch 7 in this manner , the magnitude of the initial pulse of the solid-state laser light is made closer to the magnitude of the steady pulse, and the workpiece 11 is to be marked at a constant marking depth.

[0014]

However, the control of the Q switch 7 by the control unit 5 as described above is a control which is quite difficult in reality. Usually, the magnitude of the pulse of the aforementioned solid-state laser light, et Nerugi chromatography and Q for is to be determined by the driving frequency of the switch 7, the pair <br/> to Rue Nerugi over accumulation over time If you know the relationship , Q switch 7
The drive frequency may be controlled to be constant. However, when the control in marking the beginning of the foregoing, the which it Placing et <br/> Nerugi chromatography is accumulated release amount of the previous error Nerugi over, the number of the driving frequency of the other words Q switch 7 It depends on how much storage time has passed since then. Therefore , the control of the Q switch 7 must be changed for each condition, which is theoretically possible, but actually difficult control.

[0015] In contrast, instead of controlling up to release of energy <br/> formic over the Q-switch 7, controlling the turning on and off of the excitation lamp 2 excite Y AG rod 1 Accordingly, it is conceivable to control the initial pulse by controlling the amount of accumulated error Nerugi over.

[0016] However, usually, since Y AG rod 1 in the solid-state laser time which can store error Nerugi over required to oscillate the light is about several 100 [mu] s, the excitation lamp 2 to accommodate the speed It is impossible to turn on or turn off the light at high speed, and further, there is a drawback that the life of the excitation lamp 2 is shortened by performing control such that lighting and turning off are repeated.

Therefore, the present invention provides a solid-state laser marking device which overcomes the above-mentioned problems in the prior art, facilitates the oscillation control of the initial pulse of the solid-state laser light, and improves the marking finish. The purpose is to provide.

[0018]

To SUMMARY OF THE INVENTION To achieve the above object, the solid-state laser marking device of the present onset Ming, a solid-state laser medium for storing error Nerugi over to internal by receiving light, the solid-state laser medium to a semiconductor laser for irradiating the excitation laser light, a Q-switch to diffract light to the selected択的emitted from the from the solid-state laser medium disposed in the output direction of the solid-state laser light the solid-state laser medium, the Q-switch an output mirror for arranged in the traveling direction of the light passing through the selectively reflected or passes through the light, and a total reflection mirror for the arranged output direction opposite the direction of the solid-state laser light totally reflecting the light, the output a scanner unit for the solid-state laser light passing through the mirror scanned relative workpiece, control the switching of the semiconductor laser light intensity and the Q-switch of the excitation laser light In the solid-state laser marking device and a control unit for the control unit is the steady pulse of light intensity of the excitation laser light <br/> irradiated by the semiconductor laser to the initial pulse of a solid laser beam is oscillated It is characterized in that it is controlled to be smaller than.

[0019]

In the solid-state laser marking apparatus of the present invention, the control unit controls the semiconductor laser to adjust the light intensity of the excitation laser light to excite the solid-state laser medium.
Storing error Nerugi over to the solid state laser in the medium by controlling the operation of the Q-switch. Turn on the Q switch
In to the excitation laser beam solid state laser medium a predetermined time irradiation
Morphism Then, thing that Do you et Nerugi over necessary the solid-state laser in the medium is accumulated. The children of the error Nerugi over solid-state laser light
Converts to and oscillates. At this time, the control unit turns off the Q switch to allow the solid-state laser light to pass through in the output direction without being diffracted, and also allows the output mirror to pass therethrough to enter the scanner unit. Then, the focus and the traveling direction of the solid-state laser light are adjusted via this scanner unit to mark the workpiece.

[0020] Thus, it is possible to adjust the Rue Nerugi over the amount accumulated in the solid-state laser the medium by the control unit, to the output of an initial pulse of a solid laser beam oscillated at the marking start, the control unit is the semiconductor by performing control to reduce the light intensity of the excitation laser light of the laser, a high-precision output by the solid accumulated in the laser medium Rue Nerugi over quantity adjusting initial pulse is equal to the steady state pulse magnitude and of Be sure to make proper markings.

[0021]

The present invention will be described below with reference to the embodiments shown in the drawings. It should be noted that the same components as those of the conventional one described above are denoted by the same reference numerals in the drawings, and description thereof is omitted.

FIG. 1 shows a schematic configuration diagram of a main part of a solid-state laser marking device by LD excitation as an embodiment of the present invention.

In the solid-state laser marking apparatus of this embodiment, a cylindrical YAG rod 1 which is one of solid-state laser media having excellent optical characteristics, and a side which directly irradiates an excitation laser from the side of the YAG rod 1. By pumping method
Ri semiconductor laser diode array 12 to photoexcitation the Y AG rod 1 atom (hereinafter, abbreviated as LDA12) and are arranged. The LDA 12 is connected to the power supply device 4 whose power supply is controlled by the control unit 5, and is capable of high-speed switching capable of switching between lighting and extinguishing at high speed. It has almost no adverse effects.

Then , Y A is attached to one end of the Y AG rod 1.
A total reflection mirror 6 that totally reflects light is arranged at a predetermined distance from the end surface of the G rod 1, and the other end side thereof is provided.
Y A A predetermined distance from the end surface of the rod 1 Y A
G and Q-switch 7 for diffracting light emitted from the rod 1 is arranged, Y to further AG rod 1 and the Q-switch 7
A semi-transmissive output mirror 8 that transmits a part of a predetermined solid-state laser beam is arranged on an extension line connecting the and. Then , the Q switch 7 is supplied with a voltage for operating the Q switch 7 at a specific frequency.
Are connected, and further, this Q switch drive 9
It is controlling the amount of voltage and the timing added to the Q-switch 7 Ri by the control section 5. Thus, Q switch 7 on the basis of the specific frequency, while accumulating Y AG rod 1 Gae Nerugi over <br/> is turned on, emitted when the excited atoms of Y AG rod 1 is returned to the ground state Laser light
Vibration so as not to, Y AG rod 1 when the off you Outputs a predetermined solid state laser light. Then, the output mirror 8
The scanner unit 10 having two movable mirrors (not shown) for scanning the solid-state laser light in the X and Y directions for marking the workpiece 11 is disposed at the destination of the solid-state laser light that has passed through. Has been done.

Next, the operation of this embodiment will be described.

The solid-state laser marking device according to LD pumped in this embodiment, through the control section 5 power supplies 4 L DA1
Controls turned on and off and the pumping laser beam intensity of 2, Y
Excites the atoms of the AG rod 1. At this time , L DA12
Or change in intensity of the excitation laser light intensity, because it is possible to perform high-speed switching can be freely adjusted Rue Nerugi over the amount accumulated in the YAG rod 1.

[0027] Thus, to the start of the marking, the steady pulse of the excitation laser light intensity of L DA12
Remote and small to prevent excessive accumulation of error Nerugi over as shown in (a) of FIG. When the error Nerugi over amount is accumulated required to oscillate a solid laser beam, which turns off the Q switch 7 control section 5 in together when oscillating as a solid-state laser light through the Q-switch drive 9 controlled to be, at once outputted without diffracting the solid body laser beam. Then, through the power mirror 8 out this solid-state laser light, and enters the scanner unit 10 disposed ahead. In the scanner unit 10, the scanning is for exactly workpiece 11 solid state laser light by the movable mirror (not shown)
Controlled in so that not marking is initiated.

The magnitude of the initial pulse when the oscillating a first solid-state laser light immediately after the marking start, control <br/> control unit 5 controls the excitation laser light intensity L DA 12 Y
Since the accumulation to Rue Nerugi over amount AG rod 1, was adjusted to be constant pulsed possible levels shown in FIG. 3,
As shown in (b) and (c) of FIG. 2, the magnitude is the same as the magnitude of the stationary pulse. Then, in the marking in subsequent, since the switching on and off of the Q-switch 7 is controlled at a constant driving frequency, the pumping laser beam intensity due to excitation of L DA 12 may be irradiated with light intensity of the steady state pulse.

[0029] Then, in order to move to the middle in the next marking position of the marking, to pause the output of the solid-state laser light, it moved when outputting again later, the Y AG rod 1 Ri by the passage of time for error Nerugi over is prevented from being accumulated to saturation, and reduce the light intensity of again L DA 12, to adjust the amount of Rue Nerugi over <br/> be accumulated in the Y AG rod 1 , The pulse size of the output solid-state laser light is controlled.

[0030] Therefore, according to such a configuration of the present embodiment, the braking by the control unit 5 controls the excitation laser light intensity L DA 12, to adjust the amount of accumulated error Nerugi over the YAG rod 1 Since the magnitude of the pulse, which is the intensity of the solid-state laser light, can be easily controlled, a deep marking mark such as a punch mark generated on the workpiece 11 by the initial pulse is not generated.

The present invention is not limited to the above embodiment, but can be modified as necessary.

[0032] For example, LDA12 that described above, Y AG
Is disposed laterally with respect to the rod 1 has a so-called side-pumping scheme, which may be end pumped system arranged to the incident end face excitation laser beam from the direction of the Y AG rod 1 .

The solid-state laser medium is not limited to YAG,
Ruby, glass, YLF, or the like may be used, and a quadrangular prism or slab shape other than the cylindrical shape may be used.

[0034]

As described above, according to the solid-state laser marking device of the present invention, the controller controls the intensity of the laser light for exciting LDA, so that the intensity of the pulse, which is the intensity of the solid-state laser light, can be easily adjusted. Can be controlled.

Therefore, since the initial pulse is larger than the steady pulse, a deep marking mark such as a punch mark generated on the workpiece is not generated, and it is possible to perform marking with high accuracy and excellent finish.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a main part of a solid-state laser marking device according to an embodiment of the present invention.

FIG. 2 is a timing chart regarding (a) excitation laser light intensity, (b) Q switch loss, and (c) solid laser pulse size in the solid-state laser marking device according to the embodiment of the present invention.

Ru stored in [3] laser in the medium for optical excitation time
Shows the error Nerugi over the amount of related

FIG. 4 is a configuration diagram of a main part of a conventional solid-state laser marking device.

FIG. 5: (a) Light intensity of an excitation lamp, (b) Q switch loss in a conventional solid-state laser marking device,
And (c) Respective timing charts regarding the pulse size of the solid-state laser light

FIG. 6 (a) Light intensity of an excitation lamp, (b) Q switch loss in another conventional solid-state laser marking device,
And (c) Respective timing charts regarding the pulse size of the solid-state laser light

[Explanation of reference symbols] 1 YAG rod 2 Excitation lamp 3 Cavity 4 Power supply device 5 Control unit 6 Total reflection mirror 7 Q switch 8 Output mirror 9 Q switch drive 10 Scanner unit 12 Semiconductor laser diode array (LDA)

[Procedure Amendment 2]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 3

[Correction method] Change

[Correction content]

[Figure 3]

Claims (1)

[Claims] 1. A solid-state laser medium that stores pumping energy therein by receiving light, a semiconductor laser that irradiates the laser medium with a pumping laser beam, and a solid-state laser medium arranged in the output direction of the solid-state laser beam from the laser medium. A Q switch that selectively diffracts the light emitted from the laser medium according to the amount of excitation energy accumulated in the laser medium, and a Q switch that is arranged in the traveling direction of the light passing through the Q switch to select the light. Output mirror for reflecting or passing the solid laser light, a total reflection mirror arranged in a direction opposite to the output direction of the solid-state laser light for totally reflecting the light, and a scanner for advancing the solid-state laser light passing through the output mirror toward the workpiece. A solid-state laser marking device having a control unit for controlling the light intensity of the laser light for exciting the semiconductor laser and the switching of the Q switch. The solid-state laser marking device is characterized in that the control unit controls the light intensity emitted from the semiconductor laser to be smaller than that in a steady state until the initial pulse of the solid-state laser light is oscillated.