JP5999051B2 - LASER OSCILLATION DEVICE, LASER PROCESSING DEVICE, AND PROGRAM - Google Patents

Description

  The present invention relates to a laser oscillation device, a laser processing device, and a program for driving and controlling a laser oscillator including a passive Q switch.

2. Description of the Related Art Conventionally, various proposals have been made regarding the technology of a laser processing apparatus that processes a workpiece with a laser beam.
For example, the laser system includes a power supply unit, a laser head unit, a fiber that optically connects the power supply unit and the laser head unit, and a controller that controls the operation of the power supply unit. The power supply unit includes a semiconductor laser that emits laser light as excitation light, a power supply that drives the semiconductor laser, a cooling device that cools the semiconductor laser and the power supply, and the like. The laser head unit includes a condensing lens that collects excitation light via a fiber and a fiber connector, a reflecting mirror, a laser medium, a passive Q switch, an output coupler that constitutes the reflecting mirror and a laser resonator, , And a window (see, for example, Patent Document 1).

JP 2003-332657 A

  In the laser system described in Patent Document 1, the rise of the laser output of the laser head unit is delayed. For example, as shown in FIG. 6, generally, when a workpiece is processed with laser light, the controller first drives the semiconductor laser for a time T11 [ms] with a low drive current before starting the processing. The low-output L1 [W] pumping light is output to make the pumping state low. Then, the controller outputs an ON processing signal from the processing start timing by the laser light, drives the semiconductor laser for a time T12 [ms] with a high driving current, and outputs high-power L2 [W] excitation light. In addition, when the processing by the laser beam is completed, the controller outputs an OFF processing signal, drives the semiconductor laser for a time T13 [ms] with a low driving current, and emits low-power L1 [W] excitation light. Is output to a low excitation state, and then the driving of the semiconductor laser is stopped.

  However, even if the semiconductor laser is driven for a time T12 [ms] with a high drive current from the processing start timing and the excitation light of high output L2 [W] is output, the rise of the laser output of the laser head portion is delayed. For this reason, there is a possibility that the print quality such as the processing depth of the processing trace and the processing chipping in the vicinity of the processing start of the characters, symbols, figures, etc. that are actually marked by the laser beam may be deteriorated.

  Accordingly, the present invention has been made to solve the above-described problems, and a laser oscillation apparatus, a laser processing apparatus, and a program capable of improving the printing quality of laser processing by a laser oscillator having a passive Q switch. The purpose is to provide.

In order to achieve the above object, a laser oscillation device according to claim 1 receives an excitation semiconductor laser and processing information for processing an object to be processed with laser light, and drives the excitation semiconductor laser based on the processing information. A driving pattern generation unit that generates a driving pattern, a laser driver that drives the pumping semiconductor laser, a laser medium, and a passive Q switch, and the pumping light emitted from the pumping semiconductor laser is received. When the laser medium is excited and the light energy stored in the passive Q switch exceeds a certain value, the laser driver oscillates a pulse laser, and the laser driver is driven and controlled according to the drive pattern generated by the drive pattern generator. A control unit that performs the maximum output of the excitation light that does not oscillate the pulse laser. Receiving the excitation light of higher output threshold value is a value output, and the if the output period of the excitation light is longer than the period threshold value is the minimum output period of the laser oscillator oscillates a pulsed laser through the passive Q-switch In addition, a pulse laser corresponding to the pumping light is oscillated, and the drive pattern has a first output in which the pumping light output is higher than the output threshold from a standby output state where the pumping light output is lower than the output threshold. A first output for driving the pumping semiconductor laser during a first output period during which a pulsed laser is not oscillated through the passive Q switch that is less than or equal to the period threshold, and following the first output, A second output for driving the pumping semiconductor laser with an output of the pumping light equal to or lower than the output threshold; and a second output value of the pumping light output higher than the output threshold following the second output; A third output for driving the pumping semiconductor laser, and the drive pattern generation unit starts the third output based on a start timing for starting oscillation of the pulse laser included in the processing information. The timing is set.

  Further, in the laser oscillation device according to claim 2, in the laser oscillation device according to claim 1, the drive pattern has an output value of the excitation light from an output value of the second output following the third output. A fourth output for driving the pumping semiconductor laser with a lower third output value, and the drive pattern generation unit is configured to output the fourth output based on a processing end timing of processing by the laser beam of the processing target. The output start timing is set.

  The laser oscillation device according to claim 3 is the laser oscillation device according to claim 2, wherein the drive pattern has an output of the excitation light equal to or less than the output threshold value following the fourth output. And a fifth output for driving the semiconductor laser for driving, and a sixth output for driving the pumping semiconductor laser, the output of the pumping light being the standby output following the fifth output, The generation unit sets the start timing of the sixth output based on the output stop timing of the excitation semiconductor laser.

  Furthermore, a laser oscillation device according to a fourth aspect is the laser oscillation device according to any one of the first to third aspects, wherein the drive pattern generation unit is configured to output the excitation light in the second output. The pumping semiconductor laser is driven at an output that is lower than an output threshold and higher than the standby output.

According to a fifth aspect of the present invention, there is provided a laser processing apparatus for receiving an excitation semiconductor laser and processing information for processing an object to be processed by laser light, and a drive pattern for driving the excitation semiconductor laser based on the processing information. A drive pattern generation unit for generating, a laser driver for driving the pumping semiconductor laser, a laser medium and a passive Q switch, and the laser medium receiving pumping light emitted from the pumping semiconductor laser pumping When the light energy stored in the passive Q switch exceeds a certain value, a laser oscillator that oscillates a pulse laser, and the laser driver and the laser scanning unit according to the drive pattern generated by the drive pattern generation unit A control unit for driving control and a pulse laser oscillated from the laser oscillator are scanned on the processing surface of the processing object. A laser scanning unit, wherein the laser oscillator receives pumping light having an output higher than an output threshold that is a maximum output value of the pumping light that does not oscillate the pulse laser, and an output period of the pumping light is When the laser oscillator is longer than a period threshold value that is a minimum output period for oscillating the pulse laser via the passive Q switch, the laser oscillator oscillates the pulse laser corresponding to the excitation light, and the drive pattern outputs the excitation light From the state of the standby output lower than the output threshold, the first output that does not oscillate the pulse laser through the passive Q switch whose output of the excitation light is higher than the output threshold and is equal to or less than the period threshold A first output for driving the pumping semiconductor laser for a period of time, and following the first output, the pumping laser output is less than or equal to the output threshold, A second output that moves, and following the second output, a third output that drives the pumping semiconductor laser at a second output value in which the output of the pumping light is higher than the output threshold, and The drive pattern generation unit sets the start timing of the third output based on a start timing of starting oscillation of the pulse laser included in the processing information.

According to a sixth aspect of the present invention, there is provided a program including a pumping semiconductor laser, a laser driver that drives the pumping semiconductor laser, a laser medium, and a passive Q switch, and pumping light emitted from the pumping semiconductor laser. And a laser oscillator that oscillates a pulse laser when the light energy stored in the passive Q switch exceeds a certain value when the laser medium receiving the laser beam is excited, and the laser oscillator does not oscillate the pulse laser The pumping light having an output higher than the output threshold that is the maximum output value of the pumping light is received, and the output period of the pumping light is the minimum output period in which the laser oscillator oscillates the pulse laser through the passive Q switch. When longer than the period threshold, the computer that controls the laser oscillation device that oscillates the pulse laser corresponding to the excitation light, A driving pattern generating step of receiving processing information to be processed by the laser light, generating a driving pattern for driving the pumping semiconductor laser based on the processing information, and the driving pattern generated in the driving pattern generating step; A control step of driving and controlling a laser driver, wherein the drive pattern is a standby output in which the output of the excitation light is lower than the output threshold, and the first output in which the output of the excitation light is higher than the output threshold. A first output for driving the pumping semiconductor laser during a first output period during which a pulsed laser is not oscillated through the passive Q switch that is less than or equal to the period threshold, and following the first output, The second output for driving the pumping semiconductor laser when the pumping light output is less than or equal to the output threshold, and the pumping light output is the output following the second output. And a third output for driving the semiconductor laser for excitation with a second output value higher than a threshold, and in the drive pattern generation step, at a start timing for starting oscillation of the pulse laser included in the processing information Based on this, the program is executed so as to set the start timing of the third output.

In the laser oscillation device according to claim 1, the laser processing device according to claim 5, and the program according to claim 6, the pumping semiconductor laser is driven at a first output value whose pumping light output is higher than an output threshold. the first output drive pattern that, during the first output period does not oscillate the pulsed laser via a passive Q-switch is less time threshold, after driving, followed by the output of the excitation light is driven below the output threshold By driving with the second output drive pattern , the excitation light incident on the laser oscillator with the first output drive pattern stores light energy inside the passive Q switch, and the pulse laser is not emitted. Then, the pumping semiconductor laser is driven with a third output driving pattern in which the pumping light output is driven with the second output value higher than the output threshold, and the pumping light with the second output value higher than the output threshold is emitted. Thus, the light energy stored in the passive Q switch exceeds a certain value, and the laser oscillator starts emitting the pulse laser in a short time.

Thereby, light energy can be stored inside the passive Q switch by the excitation light with the drive pattern of the first output, and the laser oscillator when the drive of the excitation semiconductor laser with the drive pattern of the third output is started. The rise time of the laser output can be shortened. Therefore, by setting the start timing of the drive pattern of the third output based on the start timing of oscillating the pulse laser included in the processing information, processing of characters, symbols, figures, etc. actually marked by the pulse laser is started. It is possible to improve the printing quality such as the processing depth of the processing trace and the processing chipping in the vicinity.

Further, in the laser oscillation apparatus according to claim 2, following the driving pattern of the third output, the fourth output the output of the excitation light is driven by the third output value lower than the output value of the second output drive pattern When the pumping semiconductor laser is driven at, the output of the pumping semiconductor laser becomes lower than the output value of the second output equal to or lower than the output threshold. As a result, the optical energy stored in the passive Q switch can be drastically lowered, the fall time of the laser output of the laser oscillator can be shortened, and the delay in stopping the oscillation of the pulse laser can be eliminated. Therefore, by setting the start timing of the fourth output drive pattern based on the processing end timing of processing by laser light, the processing marks near the end of processing of characters, symbols, figures, etc. that are actually marked by the pulse laser It is possible to improve the printing quality such as the processing depth, the curvature of the corners of the processing marks, and the processing chipping.

Further, in the laser oscillation apparatus according to claim 3, following the drive pattern of the fourth output, after driving the pumping semiconductor laser in the following output threshold value in the driving pattern of the fifth output, followed by driving of the sixth output The excitation semiconductor laser is driven with a standby output in the pattern . Thereby, the output in the standby state of the pumping semiconductor laser can be lowered, the service life of the pumping semiconductor laser can be extended, and the power consumption can be reduced.

Furthermore, in the laser oscillation device according to the fourth aspect, in the second output drive pattern , the pumping semiconductor laser is driven with an output of the pumping light below the output threshold and higher than the standby output. As a result, in the second output drive pattern , the excitation semiconductor laser is excited in the third output drive pattern , rather than in the case where the excitation semiconductor laser is driven with the standby output (for example, “0 W” output). The rise time of the light output can be shortened, and the rise time of the laser output of the laser oscillator can be further shortened.

It is a figure which shows schematic structure of the laser processing apparatus 1 which concerns on this embodiment. It is explanatory drawing which shows schematic structure of a laser oscillator. 2 is a block diagram showing an electrical configuration of the laser processing apparatus 1. FIG. 4 is a flowchart illustrating an example of a driving process in which the laser controller 3 of the laser processing apparatus 1 controls driving of the pumping semiconductor laser 28. FIG. 6 is an explanatory diagram showing a driving pattern of an excitation semiconductor laser and an operation relationship of a laser oscillator. It is explanatory drawing which shows the drive pattern of the conventional semiconductor laser for excitation, and the operation | movement relationship of a laser oscillator.

  Hereinafter, a laser oscillation device, a laser processing device, and a program according to an embodiment of the present invention will be described in detail with reference to the drawings based on an embodiment. First, a schematic configuration of the laser processing apparatus 1 according to the present embodiment will be described with reference to FIGS. 1 to 3.

  As shown in FIG. 1, a laser processing apparatus 1 according to this embodiment includes a laser processing apparatus main body 2, a laser controller 3, and a power supply unit 5. The laser processing apparatus main body 2 performs a process of marking characters, symbols, figures, and the like by two-dimensionally scanning the processing surface 6A of the processing target 6 with the laser beam L.

  The laser controller 3 is configured by a computer and is connected to a personal computer (hereinafter referred to as “PC”) 7 (see FIG. 3) so as to be capable of bidirectional communication. Electrically connected. The laser controller 3 drives and controls the laser processing apparatus main body 2 and the power supply unit 5 based on print information (processing information), control parameters, various instruction information, and the like transmitted from the PC 7. That is, the laser controller 3 controls the entire laser processing apparatus 1.

  A schematic configuration of the laser processing apparatus main body 2 will be described with reference to FIG. In the description of the laser processing apparatus body 2, the direction in which the laser beam L is emitted from the laser oscillator 11 (the left direction in FIG. 1) is the front direction of the laser processing apparatus body 2. Further, the vertical direction (the vertical direction in FIG. 1) with respect to the attachment surface of the main body base 12 to which the laser oscillator 11 is attached is the vertical direction of the laser processing apparatus main body 2. And the direction orthogonal to the up-down direction and the front-rear direction of the laser processing apparatus main body 2 is the left-right direction of the laser processing apparatus main body 2.

  As shown in FIG. 1, the laser processing apparatus main body 2 includes a main body base 12, a laser oscillation unit 13 that emits laser light L, an optical shutter unit 15, a light damper (not shown), and a half mirror (not shown). And a reflection mirror 16, an optical sensor 17, a galvano scanner 18, an fθ lens 19, and the like, and covered with a substantially rectangular parallelepiped housing cover (not shown).

  The laser oscillation unit 13 includes a laser oscillator 11, a beam expander 21, and the like. The beam expander 21 adjusts the beam diameter of the laser light L (for example, increases the beam diameter), and is provided coaxially with the laser oscillator 11. The half mirror (not shown) is disposed on the front side of the optical shutter unit 15, is disposed so as to form an angle of 45 degrees obliquely to the rear right with respect to the optical path of the laser light L, and is incident from the rear side. Transmits almost all of L.

  The half mirror reflects a part of the laser beam L incident from the rear side, for example, 1% of the laser beam L to the reflection mirror 16 at a reflection angle of 45 degrees. The reflection mirror 16 reflects the incident laser light L toward the front side at a reflection angle of 45 degrees. The optical sensor 17 is composed of a photodetector or the like that detects the light emission intensity of the laser light L, the laser light L reflected by the reflection mirror 16 is incident, and the light emission intensity of the incident laser light L is detected.

  The galvano scanner 18 is attached to the upper side of a through-hole formed in the front end portion of the main body base 12 and two-dimensionally scans the laser light L emitted from the laser oscillation unit 13 downward. The galvano scanner 18 includes a galvano X-axis motor 22 and a galvano Y-axis motor 23 that are fitted into the respective mounting holes 25 from the outside so that the respective motor shafts are orthogonal to each other. Scanning mirrors attached to the tip end face each other inside. Then, the laser light L is two-dimensionally scanned downward by controlling the rotation of the motors 22 and 23 to rotate the scanning mirrors. The two-dimensional scanning direction is a front-rear direction (X direction) and a left-right direction (Y direction).

  The fθ lens 19 condenses the laser light L that is two-dimensionally scanned by the galvano scanner 18 on the processing surface 6A of the processing target 6 disposed below. Therefore, by controlling the rotation of the motors 22 and 23, the laser light L is moved in the front-rear direction (X direction) and the left-right direction (Y direction) in a desired print pattern on the processing surface 6A of the processing target 6. Two-dimensional scanning is performed.

  Next, a schematic configuration of the power supply unit 5 will be described with reference to FIG. As shown in FIG. 1, in the power supply unit 5, an excitation semiconductor laser 28, a laser driver 29, a power supply 31, and a cooling device 32 are arranged in a casing 27. The power supply 31 supplies a driving current for driving the pumping semiconductor laser 28 to the pumping semiconductor laser 28 via the laser driver 29. The laser driver 29 DC drives the pumping semiconductor laser 28 based on drive information input from the laser controller 3 as described later.

The pumping semiconductor laser 28 is optically connected to the laser oscillator 11 by an optical fiber 33. The pumping semiconductor laser 28 emits laser light having a wavelength λ ₁ with an output [W] proportional to the current value exceeding the threshold current for generating laser light with respect to the pulsed drive current input from the laser driver 29. The light is emitted into the optical fiber 33. Therefore, the laser oscillator 11 receives the laser light having the wavelength λ ₁ of the pumping semiconductor laser 28 (hereinafter referred to as “pumping light”) through the optical fiber 33. As the pumping semiconductor laser 28, for example, a laser bar using GaAs can be used.

  The cooling device 32 cools the power source 31 and the pumping semiconductor laser 28 by an electronic cooling method, and controls the temperature of the pumping semiconductor laser 28, so that the oscillation wavelength of the pumping semiconductor laser 28 can be finely adjusted. The cooling device 32 may be a water cooling type cooling device, an air cooling type cooling device or the like.

  Next, a schematic configuration of the laser oscillator 11 will be described with reference to FIG. As shown in FIG. 2, the laser oscillator 11 includes a fiber connector 36, a condensing lens 37, a reflecting mirror 38, a laser medium 39, a passive Q switch 41, an output coupler 42, a window, and a casing 35. 43 is arranged. An optical fiber 33 is connected to the fiber connector 36, and excitation light emitted from the excitation semiconductor laser 28 is incident through the optical fiber 33.

The condensing lens 37 condenses the excitation light incident from the fiber connector 36. The reflecting mirror 38 transmits the excitation light condensed by the condenser lens 37 and reflects the laser light emitted from the laser medium 39 with high efficiency. The laser medium 39 is excited by the excitation light emitted from the excitation semiconductor laser 28 and oscillates the laser light. Examples of the laser medium 39 include neodymium-added gadolinium vanadate (Nd: GdVO ₄ ) crystal to which neodymium (Nd) is added as a laser active ion, neodymium-added yttrium vanadate (Nd: YVO ₄ ) crystal, Nd: A YAG crystal or the like can be used.

The passive Q switch 41 is a crystal having a property that when the light energy stored inside exceeds a certain value, the transmittance becomes 80% to 90%. Accordingly, the passive Q switch 41 functions as a Q switch that oscillates the laser light oscillated by the laser medium 39 as a pulsed pulse laser. As the passive Q switch 41, for example, a chrome YAG (Cr: YAG) crystal or a Cr: MgSiO ₄ crystal can be used. Therefore, the laser oscillator 11 oscillates a pulse laser through the passive Q switch 41.

  The output coupler 42 constitutes a reflecting mirror 38 and a laser resonator. The output coupler 42 is, for example, a partial reflecting mirror constituted by a concave mirror whose surface is coated with a dielectric layer film, and the reflectance at a wavelength of 1063 nm is 80% to 95%. The window 43 is formed of synthetic quartz or the like, and transmits the laser light emitted from the output coupler 42 to the outside.

Therefore, the laser oscillator 11 receives pumping light having an output higher than the “output threshold” that is the maximum output value of pumping light that does not oscillate the pulse laser from the pumping semiconductor laser 28 via the optical fiber 33, and pumping light. When the output period is longer than the “period threshold” that is the minimum output period in which the laser oscillator 11 oscillates the pulse laser, the pulse of wavelength λ ₂ having an average output proportional to the output value exceeding the output threshold of the excitation light Oscillates the laser. The “output threshold” and “period threshold” are determined by the characteristics of the pumping semiconductor laser 28, the type of Nd: YVO ₄ crystal, Nd: YAG crystal, or a combination thereof.

  Next, the circuit configuration of the laser processing apparatus 1 will be described with reference to FIG. As shown in FIG. 3, the laser processing apparatus 1 includes a laser controller 3 that controls the entire laser processing apparatus 1, a galvano controller 45, a galvano driver 46, a laser driver 29, and the like. The laser controller 3 is electrically connected with a galvano controller 45, a laser driver 29, an optical sensor 17, and the like.

  In addition, the PC 7 is connected to the laser controller 3 so as to be capable of two-way communication, and is configured to be able to receive print information transmitted from the PC 7, control parameters of the laser processing apparatus main body 2 and various instruction information from the user. Yes. The PC 7 is electrically connected to an input operation unit 61 including a mouse and a keyboard, a liquid crystal display (LCD) 62, and the like via an input / output interface (not shown).

  The laser controller 3 includes an arithmetic unit that performs overall control of the laser processing apparatus 1, a CPU 51 as a control unit, a RAM 52, a ROM 53, a timer 54 that measures time, and the like. The CPU 51, RAM 52, ROM 53, and timer 54 are connected to each other via a bus line (not shown), and exchange data with each other.

  The RAM 52 is for temporarily storing various calculation results calculated by the CPU 51, XY coordinate data of the print pattern, and the like. The ROM 53 stores various programs, and stores various programs such as calculating the XY coordinate data of the print pattern based on the print information transmitted from the PC 7 and storing it in the RAM 52. The ROM 53 stores data such as the start point, end point, focus, curvature, etc. of the font of each character composed of straight lines and elliptical arcs for each type of font. The ROM 53 stores a drive processing program (see FIG. 4) for driving and controlling an excitation semiconductor laser 28 described later.

  The CPU 51 performs various calculations and controls based on various programs stored in the ROM 53. For example, the CPU 51 outputs XY coordinate data, galvano scanning speed information, and the like of the print pattern calculated based on the print information input from the PC 7 to the galvano controller 45. In addition, the CPU 51 uses the driving information of the pumping semiconductor laser 28 such as the pumping light output [W] and the pumping light output period [ms] set based on the print information input from the PC 7 as laser. Output to the driver 29. Further, the CPU 51 outputs XY coordinate data of the print pattern, a processing signal for instructing ON / OFF of the galvano scanner 18, and the like to the galvano controller 45.

  The galvano controller 45 calculates the drive angle, rotation speed, and the like of the galvano X-axis motor 22 and the galvano Y-axis motor 23 based on the XY coordinate data, galvano scanning speed information, etc. of the print pattern input from the laser controller 3. Motor drive information representing the drive angle and rotation speed is output to the galvano driver 46. The galvano driver 46 drives and controls the galvano X-axis motor 22 and the galvano Y-axis motor 23 based on the motor drive information indicating the drive angle and rotation speed input from the galvano controller 45, and performs two-dimensional scanning with the laser light L. To do.

  The laser driver 29 drives the pumping semiconductor laser 28 based on the laser driving information such as the pumping light output [W] and the pumping light output period [ms] input from the laser controller 3. Control. Specifically, the laser driver 29 generates a pulsed drive current having a current value proportional to the excitation light output [W] of the laser drive information input from the laser controller 3, and outputs the excitation light of the laser drive information. During the period [ms], the laser beam is output to the pumping semiconductor laser 28. As a result, the pumping semiconductor laser 28 emits pumping light with pumping light output [W] into the optical fiber 33 during the output period [ms].

[Driving process of semiconductor laser 28 for excitation]
Next, in the laser processing apparatus 1 configured as described above, a driving process in which the CPU 51 of the laser controller 3 drives and controls the pumping semiconductor laser 28 will be described with reference to FIGS. 4 and 5. The CPU 51 sets “processing speed” for marking the workpiece 6 from the PC 7 with the laser beam L (pulse laser), “laser power” of the laser beam L, start timing for starting oscillation of the laser beam L, characters, symbols. When printing information such as graphics is received and a processing start instruction by laser light is input, the processing of S11 to S22 of FIG. 4 is executed.

  As shown in FIG. 4, first, in step (hereinafter abbreviated as “S”) 11, the CPU 51 calculates XY coordinate data of the print pattern based on the received “marking data” such as characters, symbols, and figures. Store in the RAM 52. Further, the CPU 51 calculates the excitation light output [W] output during processing of the excitation semiconductor laser 28 from the laser power [W] of the laser light L and stores it in the RAM 52. For example, as shown in the upper and middle stages of FIG. 5, the CPU 51 generates the pumping light output L2 [W] of the pumping semiconductor laser 28 with respect to the output P1 [W] of the laser light L oscillated by the laser oscillator 11 during processing. Calculate and store in RAM 52.

  Then, the CPU 51 generates a drive pattern for the excitation semiconductor laser 28 and stores it in the RAM 52. For example, as shown in the middle part of FIG. 5, the CPU 51 generates a drive pattern of the pumping semiconductor laser 28 that is composed of the standby state W0 and the first output W1 to the sixth output W6. Specifically, first, the CPU 51 starts from the standby state W0 of the standby output where the excitation light output is 0 [W], and the excitation light output L2 [W] during processing (for example, L2 = 24 [W]). In addition, the first output period T1 [ms] (for example, T1 = 3 [ms]) in which the output period of the excitation light is equal to or less than the “period threshold” that is the minimum output period in which the laser oscillator 11 oscillates the pulse laser. .) Is set and stored in the RAM 52.

  The standby output in the standby state W0 may be set to an arbitrary output from 0 [W] to an excitation light output L3 [W] described later (for example, L3 = 5 [W]). . The pumping light output of the first output W1 is lower than the pumping light output L2 [W] at the time of processing, and is the “output threshold value” which is the maximum output value of pumping light at which the laser oscillator 11 does not oscillate the pulse laser. May be set to a higher output (for example, 20 [W]) than L1 [W] (for example, L1 = 6 [W]).

  Then, following the first output W1, the CPU 51 starts from the first output period T1 [ms] at L1 [W] of “output threshold” that is the maximum output value of the pumping light that the laser oscillator 11 does not oscillate the pulse laser. The second output W2 of the second output period T2 [ms] (for example, T2 = 10 [ms]) is set and stored in the RAM 52. Therefore, at the second output W2, the laser oscillator 11 does not oscillate the pulse laser, so the low excitation state by the excitation light of the first output W1 is maintained, and light energy is stored in the passive Q switch 41.

  Then, following the second output W2, the CPU 51 performs two-dimensional scanning of the laser light L with the excitation light output L2 [W] at the time of processing and the output period of the excitation light to display characters, symbols, figures, etc. A time for processing the processing surface 6 </ b> A of the processing object 6, that is, a third output W <b> 3 in a third output period T <b> 3 [ms] (for example, T <b> 3 = 100 [ms]) is set and stored in the RAM 52. The CPU 51 calculates the third output period T3 [ms] from the “total processing length” of characters, symbols, figures, etc. and the “processing speed” marking with the laser beam L.

  Then, following the third output W3, the CPU 51 causes the pumping light output L3 [W] (lower than L1 [W] of the “output threshold” that is the maximum output value of the pumping light at which the laser oscillator 11 does not oscillate the pulse laser. For example, L3 = 5 [W]), and the time when the laser oscillator 11 is in a low excitation state and does not oscillate the pulse laser, that is, the fourth output period T4 [ms] (for example, T4 = 1 [ms]). The fourth output W4 is set and stored in the RAM 52.

  Subsequently to the fourth output W4, the CPU 51 sets the second output period T2 [ms] at L1 [W] of the “output threshold” that is the maximum output value of the pumping light that the laser oscillator 11 does not oscillate the pulse laser. A fifth output W5 of a fifth output period T5 [ms] (for example, T5 = 10 [ms]), which is substantially the same output period, is set and stored in the RAM 52. Further, following the fifth output W5, the CPU 51 sets a sixth output W6, which is a standby output with an excitation light output of 0 [W], and stores it in the RAM 52.

  Subsequently, in S12, the CPU 51 reads the excitation light output L2 [W] of the first output W1 and the first output period T1 [ms] from the drive pattern of the excitation semiconductor laser 28 stored in the RAM 52, and the laser Output to the driver 29. As a result, the pumping semiconductor laser 28 is DC driven by the laser driver 29 during the first output period T1 [ms], and emits pumping light having an output L2 [W] into the optical fiber 33. As a result, as shown in the upper and middle stages of FIG. 5, the laser oscillator 11 enters the laser medium 39 via the optical fiber 33, oscillates the laser light, enters a low excitation state, and is passive. Light energy is stored in the Q switch 41, but the pulse laser is not emitted by the action of the passive Q switch 41.

  In S12, the CPU 51 obtains the time obtained by subtracting the total time of the first output period T1 [ms] and the second output period T2 [ms] from the start timing at which the oscillation of the laser beam L received from the PC 7 is started. The pumping light output L2 [W] of one output W1 and the first output period T1 [ms] are set as the timing for outputting to the laser driver 29.

  In S13, the CPU 51 reads the excitation light output L1 [W] of the second output W2 and the second output period T2 [ms] from the drive pattern of the excitation semiconductor laser 28 stored in the RAM 52, and the laser driver. 29. Accordingly, the pumping semiconductor laser 28 is DC-driven by the laser driver 29 during the second output period T2 [ms], and emits pumping light having an output L1 [W] into the optical fiber 33. As a result, as shown in the upper stage and middle stage of FIG. 5, the laser oscillator 11 receives the pumping light that does not oscillate the pulsed laser through the optical fiber 33, so that the low excitation by the pumping light of the first output W1. The state is maintained and the pulse laser is not emitted.

  Subsequently, in S <b> 14, the CPU 51 executes a determination process for determining whether or not to start processing with the laser beam L. Specifically, the CPU 51 outputs the excitation light output L1 [W] of the second output W2 and the second output period T2 [ms] to the laser driver 29, and then the time of the second output period T2 [ms] has elapsed. A determination process for determining whether or not the process has been performed is executed. That is, the CPU 51 executes a determination process for determining whether or not the start timing for starting the oscillation of the laser beam L (pulse laser) has come.

  When it is determined that the processing is not started by the laser light L, that is, the time of the second output period T2 [ms] has not elapsed (S14: NO), the CPU 51 executes the processes after S14 again. .

  On the other hand, when it is determined that the processing is started by the laser light L, that is, the time of the second output period T2 [ms] has elapsed (S14: YES), the CPU 51 proceeds to the process of S15. In S <b> 15, the CPU 51 reads the excitation light output L <b> 2 [W] of the third output W <b> 3 and the third output period T <b> 3 [ms] from the drive pattern of the excitation semiconductor laser 28 stored in the RAM 52, and sends it to the laser driver 29. Output. Accordingly, the pumping semiconductor laser 28 is DC-driven by the laser driver 29 during the third output period T3 [ms], and emits pumping light having an output L2 [W] into the optical fiber 33.

  As a result, as shown in the upper and middle stages of FIG. 5, the laser oscillator 11 is brought into a low excitation state, which is a low energy state that does not oscillate the pulse laser, by the excitation light output L2 [W] of the first output W1. Therefore, laser light is incident on the laser medium 39 via the optical fiber 33, and the state is changed to a high excitation state, which is a high energy state in which a pulse laser is oscillated in a short time. As a result, since the passive Q switch 41 stores optical energy by the pumping light output L2 [W] having the first output W1, the laser oscillator 11 can perform the pulse laser having the laser output P1 [W] in a short time. Laser light L is emitted from the window 43.

  In S <b> 16, the CPU 51 outputs the XY coordinate data of the print pattern and the “processing speed” data received from the PC 7 to the galvano controller 45. Then, as shown in the lower part of FIG. 5, the CPU 51 sets the processing signal for instructing the processing start by the laser light L to “ON” and outputs it to the galvano controller 45. Thereby, the galvano controller 45 starts driving the galvano X-axis motor 22 and the galvano Y-axis motor 23 according to the XY coordinate data of the print pattern, and scans the laser beam L two-dimensionally to display characters, symbols, figures, etc. The processed surface 6 is processed into a processed surface 6A.

  Subsequently, in S <b> 17, the CPU 51 executes a determination process for determining whether or not the processing by the laser beam L is finished. Specifically, the CPU 51 outputs the excitation light output L2 [W] of the third output W3 and the third output period T3 [ms] to the laser driver 29, and then the time of the third output period T3 [ms] has elapsed. A determination process for determining whether or not the process has been performed is executed. When it is determined that the processing by the laser beam L is not finished, that is, the time of the third output period T3 [ms] has not elapsed (S17: NO), the CPU 51 executes the processes after S17 again.

  On the other hand, when it is determined that the processing by the laser beam L is finished, that is, the time of the third output period T3 [ms] has elapsed (S17: YES), the CPU 51 proceeds to the process of S18. In S <b> 18, the CPU 51 reads the excitation light output L <b> 3 [W] of the fourth output W <b> 4 and the fourth output period T <b> 4 [ms] from the drive pattern of the excitation semiconductor laser 28 stored in the RAM 52, and sends it to the laser driver 29. Output. As a result, the pumping semiconductor laser 28 is DC driven by the laser driver 29 for the fourth output period T4 [ms], and the pumping light output L3 [W] lower than the pumping light output L1 [W] of the second output W2. ] Is emitted into the optical fiber 33.

  As a result, as shown in the upper and middle stages of FIG. 5, the laser oscillator 11 is shifted from the high excitation state to the low excitation state in a short time by the excitation light output L3 [W] of the fourth output W4. Thereby, in the laser oscillator 11, the light energy stored in the passive Q switch 41 is rapidly reduced, and the emission of the laser beam L of the pulse laser having the laser output P1 [W] is stopped in a short time.

  In S <b> 19, the CPU 51 sets the processing signal for instructing the processing start by the laser light L to “OFF” and outputs the processing signal to the galvano controller 45 as shown in the lower part of FIG. 5. Thereby, the galvano controller 45 stops the driving of the galvano X-axis motor 22 and the galvano Y-axis motor 23 and ends the two-dimensional scanning of the laser light L.

  Subsequently, in S20, the CPU 51 reads the pumping light output L1 [W] of the fifth output W5 and the fifth output period T5 [ms] from the driving pattern of the pumping semiconductor laser 28 stored in the RAM 52, and performs laser processing. Output to the driver 29. Thus, the pumping semiconductor laser 28 is DC driven by the laser driver 29 for the fifth output period T5 [ms], and the pumping light of the pumping light output L1 [W] of the fifth output W5 is input into the optical fiber 33. Exit. As a result, as shown in the upper and middle stages of FIG. 5, the laser oscillator 11 does not emit the pulse laser because the excitation light that does not oscillate the pulse laser is incident through the optical fiber 33.

  Thereafter, in S21, the CPU 51 executes a determination process for determining whether to stop driving the pumping semiconductor laser 28 and stop the output of pumping light. Specifically, the CPU 51 outputs the excitation light output L1 [W] of the fifth output W5 and the fifth output period T5 [ms] to the laser driver 29, and then the time of the fifth output period T5 [ms] has elapsed. A determination process for determining whether or not the process has been performed is executed. Then, when it is determined that the driving of the pumping semiconductor laser 28 is not stopped, that is, the time of the fifth output period T5 [ms] has not elapsed (S21: NO), the CPU 51 again performs the processing after S21. Execute.

  On the other hand, when the driving of the pumping semiconductor laser 28 is stopped, that is, when it is determined that the time of the fifth output period T5 [ms] has elapsed (S21: YES), the CPU 51 proceeds to the process of S22. In S <b> 22, a standby output in which the excitation light output of the sixth output W <b> 6 is 0 [W] is read from the drive pattern of the excitation semiconductor laser 28 stored in the RAM 52, and is output to the laser driver 29. As a result, the driving of the pumping semiconductor laser 28 by the laser driver 29 is stopped, and the incidence of the pumping light on the optical fiber 33 is stopped. Thereafter, the CPU 51 ends the process.

  Here, the laser controller 3 functions as an example of a drive pattern generation unit and a control unit. The laser controller 3, the power supply unit 5, and the laser oscillation unit 13 constitute an example of a laser oscillation device. The galvano scanner 18, the galvano driver 46, and the galvano controller 45 constitute an example of a laser scanning unit.

  As described in detail above, in the laser processing apparatus 1 according to the present embodiment, the CPU 51 of the laser controller 3 drives the excitation semiconductor laser 28 with the first output W1, and then drives it with the second output W2. As a result, the excitation light incident on the laser oscillator 11 with the first output W1 causes the laser oscillator 11 to oscillate the laser light to be in a low excitation state, and light energy is stored inside the passive Q switch 41. The laser beam L of the laser is not emitted. Then, by driving the pumping semiconductor laser 28 with the third output W3 and emitting the pumping light, the light energy stored in the passive Q switch 41 exceeds a certain value, and the laser oscillator 11 Start emitting pulsed laser.

  As a result, the optical energy can be stored inside the passive Q switch 41 by the pumping light at the first output W1, and the laser of the laser oscillator 11 when the driving of the pumping semiconductor laser 28 is started at the third output W3. Output rise time can be shortened. Accordingly, by setting the start timing of the third output W3 as the processing start timing for processing with the laser light L, processing of the processing marks in the vicinity of the processing start of characters, symbols, figures, etc. that are actually marked with the laser light L It is possible to improve printing quality such as depth and chipping.

  Further, by driving the pumping semiconductor laser 28 with the fourth output W4 following the third output W3, the pumping semiconductor laser 28 has a pumping light lower than the pumping light output L1 [W] of the second output W2. Excitation light of output L3 [W] is emitted into the optical fiber 33. As a result, the light energy stored in the passive Q switch 41 can be drastically lowered, the fall time of the laser output of the laser oscillator 11 can be shortened, and the delay in stopping the oscillation of the pulse laser can be eliminated. Accordingly, by setting the start timing of the fourth output W4 at the processing end timing of processing by the laser light L, processing of the processing marks near the processing end of characters, symbols, figures, etc. that are actually marked by the laser light L It is possible to improve the printing quality such as the depth, the curvature of the corner of the processing mark, and the processing chip.

  Further, after the fourth output W4, the pumping semiconductor laser 28 is driven by the pumping light output L1 [W] that does not oscillate the pulse laser by the fifth output W5, and then the pumping light output is 0 [W by the sixth output W6. ], The pumping semiconductor laser 28 is driven. As a result, the output of the pumping semiconductor laser 28 in the standby state can be set to 0 [W], the service life of the pumping semiconductor laser 28 can be extended, and the power consumption can be reduced.

  In addition, this invention is not limited to the said embodiment, Of course, various improvement and deformation | transformation are possible within the range which does not deviate from the summary of this invention. In the following description, the same reference numerals as those of the laser processing apparatus 1 according to the embodiment in FIGS. 1 to 5 denote the same or corresponding parts as those of the laser processing apparatus 1 according to the embodiment. It is.

  For example, the pumping light output of the pumping semiconductor laser 28 at the second output W2 is equal to or less than L1 [W] of the “output threshold” that is the maximum output value of pumping light that the laser oscillator 11 does not oscillate the pulse laser, and is in standby You may set so that it may become larger than standby output 0 [W] of state W0. For example, it is desirable to set the pumping light output of the pumping semiconductor laser 28 at the second output W2 to 50% or more of L1 [W] of the “output threshold”. As a result, the rise time of the pumping light output of the pumping semiconductor laser 28 at the third output W3 is set longer than when the pumping light output of the pumping semiconductor laser 28 at the second output W2 is set to the standby output 0 [W]. The rise time of the laser output of the laser oscillator 11 can be shortened.

DESCRIPTION OF SYMBOLS 1 Laser processing apparatus 3 Laser controller 11 Laser oscillator 28 Excitation semiconductor laser 29 Laser driver 33 Optical fiber 39 Laser medium 41 Passive Q switch 51 CPU
52 RAM
53 ROM
54 Timer

Claims (6)

A pumping semiconductor laser;
A driving pattern generating unit that receives processing information to be processed by a laser beam on a processing target, and generates a driving pattern for driving the excitation semiconductor laser based on the processing information;
A laser driver for driving the pumping semiconductor laser;
When the laser medium having a laser medium and a passive Q switch and receiving the pumping light emitted from the pumping semiconductor laser is excited and the light energy stored in the passive Q switch exceeds a certain value, a pulse is generated. A laser oscillator that oscillates a laser;
A control unit that drives and controls the laser driver according to the drive pattern generated by the drive pattern generation unit;
With
The laser oscillator receives pumping light having an output higher than an output threshold that is a maximum output value of the pumping light that does not oscillate the pulse laser, and the laser oscillator outputs the passive Q switch during an output period of the pumping light. Oscillates the pulse laser corresponding to the excitation light when the period is longer than the threshold, which is the minimum output period for oscillating the pulse laser via
The drive pattern is
From a standby output state in which the output of the excitation light is lower than the output threshold, the pulse laser is passed through the passive Q switch having a first output value in which the output of the excitation light is higher than the output threshold and not more than the period threshold. A first output for driving the pumping semiconductor laser during a first output period during which no oscillation occurs ;
Following the first output, a second output that drives the pumping semiconductor laser when the pumping light output is equal to or lower than the output threshold;
Following the second output, a third output for driving the pumping semiconductor laser with a second output value in which the output of the pumping light is higher than the output threshold;
Have
The drive pattern generation unit sets the start timing of the third output based on the start timing of starting the oscillation of the pulse laser included in the processing information. The drive pattern has a fourth output for driving the pumping semiconductor laser with a third output value lower than the output value of the second output, following the third output.
2. The laser oscillation device according to claim 1, wherein the drive pattern generation unit sets the start timing of the fourth output based on a processing end timing of processing by the laser beam of the processing object. The drive pattern is
Subsequent to the fourth output, a fifth output for driving the pumping semiconductor laser when the output of the pumping light is equal to or lower than the output threshold value;
Subsequent to the fifth output, the output of the pumping light is the standby output, and the sixth output for driving the pumping semiconductor laser;
Have
3. The laser oscillation device according to claim 2, wherein the drive pattern generation unit sets a start timing of the sixth output based on an output stop timing of the excitation semiconductor laser.   The drive pattern generation unit drives the pumping semiconductor laser at the second output with an output of the pumping light equal to or lower than the output threshold and higher than the standby output. The laser oscillation device according to any one of claims 1 to 3. A pumping semiconductor laser;
A driving pattern generating unit that receives processing information to be processed by a laser beam on a processing target, and generates a driving pattern for driving the excitation semiconductor laser based on the processing information;
A laser driver for driving the pumping semiconductor laser;
When the laser medium having a laser medium and a passive Q switch and receiving the pumping light emitted from the pumping semiconductor laser is excited and the light energy stored in the passive Q switch exceeds a certain value, a pulse is generated. A laser oscillator that oscillates a laser;
A control unit that drives and controls the laser driver and the laser scanning unit according to the drive pattern generated by the drive pattern generation unit;
A laser scanning unit that scans a processing surface of a processing object with a pulse laser oscillated from the laser oscillator;
With
The laser oscillator receives pumping light having an output higher than an output threshold that is a maximum output value of the pumping light that does not oscillate the pulse laser, and the laser oscillator outputs the passive Q switch during an output period of the pumping light. Oscillates the pulse laser corresponding to the excitation light when the period is longer than the threshold, which is the minimum output period for oscillating the pulse laser via
The drive pattern is
From a standby output state in which the output of the excitation light is lower than the output threshold, the pulse laser is passed through the passive Q switch having a first output value in which the output of the excitation light is higher than the output threshold and not more than the period threshold. A first output for driving the pumping semiconductor laser during a first output period during which no oscillation occurs ;
Following the first output, a second output that drives the pumping semiconductor laser when the pumping light output is equal to or lower than the output threshold;
Following the second output, a third output for driving the pumping semiconductor laser with a second output value in which the output of the pumping light is higher than the output threshold;
Have
The drive pattern generation unit sets a start timing of the third output based on a start timing of starting oscillation of the pulse laser included in the processing information. An excitation semiconductor laser, a laser driver that drives the excitation semiconductor laser, a laser medium and a passive Q switch, and a laser medium that receives excitation light emitted from the excitation semiconductor laser is excited; A laser oscillator that oscillates a pulse laser when light energy stored in the passive Q switch exceeds a certain value, and the laser oscillator is an output threshold value that is a maximum output value of the excitation light that does not oscillate the pulse laser When the pumping light having a higher output is received and the output period of the pumping light is longer than a period threshold which is a minimum output period in which the laser oscillator oscillates a pulse laser through the passive Q switch , the pumping light In a computer that controls a laser oscillation device that oscillates a pulse laser corresponding to
A driving pattern generating step of receiving processing information to be processed by a laser beam on a processing object, and generating a driving pattern for driving the excitation semiconductor laser based on the processing information;
A control step of driving and controlling the laser driver according to the drive pattern generated in the drive pattern generation step;
And execute
The drive pattern is
From a standby output state in which the output of the excitation light is lower than the output threshold, the pulse laser is passed through the passive Q switch having a first output value in which the output of the excitation light is higher than the output threshold and not more than the period threshold. A first output for driving the pumping semiconductor laser during a first output period during which no oscillation occurs ;
Following the first output, a second output that drives the pumping semiconductor laser when the pumping light output is equal to or lower than the output threshold;
Following the second output, a third output for driving the pumping semiconductor laser with a second output value in which the output of the pumping light is higher than the output threshold;
Have
A program that is executed in the drive pattern generation step so as to set a start timing of the third output based on a start timing of starting oscillation of the pulse laser included in the processing information.

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