JP2002336984A - Laser beam machining device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a laser beam machining device that is less liable to cause deviation of machining position in the laser beam machining such as laser drilling. SOLUTION: In forming a drilled hole in a machining station, an evaluation part 52 detects acceleration signals from vibration sensors 58a-58c provided in proper places in the machining station or the like. When the evaluation part 52 evaluates that, on the basis of the acceleration signals, the deviation of the machining position on a workpiece W is in excess of a prescribed allowable value, the evaluation part 52 outputs a signal for prohibiting the output of a trigger signal to a trigger signal generating part 53a to stop the emission of a laser beam LB from a laser generator 40. Thus, the formation of the drilled hole with a positional deviation from the allowable error or above can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laser drilling machine for forming a via hole in a printed wiring board and other laser processing devices.

[0002]

2. Description of the Related Art A conventional laser drill machine includes a processing station for actually drilling a printed wiring board;
The apparatus includes a substrate transfer device that automatically supplies and discharges a printed wiring board to and from a processing station, and a laser oscillation device that generates laser light for processing. Here, the processing station causes an XY stage for supporting and moving the printed wiring board to an appropriate position, and causes a processing laser beam from a laser oscillation device to enter a desired position on the printed wiring board supported by the XY stage. A scanning optical system.

[0003] Explaining the boring process by the above apparatus, first, an unprocessed printed wiring board is supplied to a processing station from a substrate transfer device on the supply side. Next, while operating the laser oscillation device and the scanning optical system, a laser beam is incident on an appropriate position of the printed wiring board in the processing station to form a VIA hole therein. More specifically, the XY stage is moved so that a specific small area on the printed wiring board becomes an irradiation area of the scanning optical system. Next, VIA holes are formed in a desired arrangement in a specific small area on the printed wiring board by a scanning optical system.
Next, the XY stage is moved so that the small area adjacent to the specific small area becomes the irradiation area of the scanning optical system. Next, via holes are formed in a desired arrangement in the adjacent small areas on the printed wiring board by a scanning optical system. By repeating the above operation, a VIA hole can be formed at an appropriate position on the entire printed wiring board. Finally, the processed printed wiring board is discharged from the processing station to the substrate transfer device on the discharge side.

[0004]

In the laser drilling machine described above, the vibration accompanying the driving of the substrate transfer device and the XY stage causes a slight distortion in the structure of the processing station. Due to such a distortion, a relative position shift occurs between the XY stage and the scanning optical system, although momentarily, and as a result, the processed hole is shifted from a desired position. In addition, the vibration source exists not only in the apparatus body of the laser drill machine but also in the vicinity of the installation environment, and there is a possibility that the positional deviation of the processing hole occurs at an unexpected timing.

Accordingly, an object of the present invention is to provide a laser processing apparatus in which a processing position is less likely to be shifted during laser processing with a laser drill or the like.

[0006]

In order to solve the above-mentioned problems, a laser processing apparatus according to the present invention comprises a processing light irradiating means for irradiating a predetermined processing position on a workpiece with processing light, and a position of the predetermined processing position. A plurality of sensor means for individually detecting vibrations at a plurality of locations affecting the displacement; and, based on the vibrations detected by the plurality of sensor means, whether a positional deviation amount of the predetermined processing position exceeds a predetermined allowable value. Evaluation means for evaluating whether or not the processing light irradiates the processing light by controlling the operation of the processing light irradiating means when the evaluation means evaluates that the displacement amount exceeds the predetermined allowable value. Operation control means for temporarily prohibiting the operation.

In the above apparatus, the evaluation means evaluates whether or not the displacement exceeds a predetermined allowable value on the basis of vibrations at a plurality of locations which affect the displacement of the processing position. It is possible to monitor the state of occurrence of the position shift in consideration of the vibration at a key point of the device. Further, the operation control means controls the operation of the processing light irradiation means to temporarily irradiate the processing light when the evaluation means evaluates that the displacement amount exceeds the predetermined allowable value. Therefore, it is possible to prevent the laser processing from being performed in a state where the amount of displacement is large while taking into account the vibration situation at a key point of the laser processing apparatus, and to reliably prevent the occurrence of the displacement of the processing hole. it can.

In a specific aspect of the above-mentioned apparatus, the plurality of sensor means are acceleration sensors for detecting vibrations at the plurality of locations as acceleration signals, respectively, and the evaluating means includes an acceleration sensor for detecting a vibration from each of the plurality of sensor means. The evaluation is performed by comparing each displacement amount signal obtained by integrating the acceleration signal with a limit value corresponding to the predetermined allowable value. In this case, it is possible to set the limit value of the displacement at a plurality of locations, which is a detection measure, in accordance with the limit of the positional deviation allowed at the predetermined processing position. Can be advanced, and the processing accuracy can be increased while preventing a decrease in throughput.

In another specific aspect of the above-mentioned device, the evaluation means calculates relative displacements of the plurality of locations based on vibrations detected by the plurality of sensor means, and calculates the relative displacement at the plurality of locations. The amount of deviation is directly evaluated. In this case, the position shift amount can be more accurately evaluated, so that the delay of the processing due to the prohibition of the irradiation of the processing light can be minimized.

In another specific mode of the apparatus, the apparatus further comprises a stage for supporting and moving the work.
The processing light irradiating unit has a light source and an irradiation optical system that causes the processing light from the light source to enter the processing position, and the plurality of sensor units are divided into the light source, the irradiation optical system, and the stage. And three sensor units that individually detect the vibrations at the plurality of locations as acceleration signals, wherein the evaluation unit corresponds to the light source, the irradiation optical system, and the stage from the three sensor units, respectively. Based on the acceleration signal, it is evaluated whether the displacement amount exceeds the predetermined allowable value. In this case, since three sensor units are provided in consideration of the individual vibrations of the light source, the irradiation optical system, and the stage, it is determined whether or not the displacement amount exceeds the predetermined allowable value. More accurate evaluation can be made in accordance with the cause of the shift.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] FIG. 1 is a perspective view illustrating a specific structure of a laser processing apparatus according to a first embodiment of the present invention.

This laser processing apparatus comprises a processing station 10 which is a main body for actually drilling a work W which is a printed wiring board, and a loader device 2 which automatically supplies the work W which is a printed wiring board to the processing station 10.
0, an unloader device 30 that automatically unloads the work W from the processing station 10, a laser oscillation device 40 that supplies a laser beam for processing to the scanning optical system 16 provided in the processing station 10, and an operation of the laser oscillation device 40. An irradiation control device 50 for controlling the laser processing device and a main control device 60 for controlling the operation of the entire laser processing device are provided. Note that the laser oscillation device 40 and the scanning optical system 16 constitute a processing light irradiation unit.

The processing station 10 includes an XY stage 12 that supports the workpiece W in the processing chamber and is movable with the workpiece W, a stage driving device 14 that drives the XY stage 12 to move it to an appropriate position, and an XY stage. A scanning optical system 16 for irradiating a processing laser beam LB at a desired position on the surface of the work W supported on the stage 12. Although not shown, the scanning optical system 16 has a pair of galvano scanners for scanning and an fθ lens for focusing, and scans the incident spot of the laser beam LB incident on the work W in the XY plane. It can be moved to any point. That is, a required number of processing holes H can be formed at an arbitrary position on the work W.

The loader device 20 accommodates a cassette (not shown) for accommodating a plurality of works W, takes out unprocessed works W one by one from the cassette, and places it on the XY stage 12 in the processing station 10. A transfer robot (not shown) for mounting is provided.

The unloader device 30 also houses a cassette (not shown) capable of storing a plurality of works W, and stores the processed works W on the XY stage 12 in the processing station 10 one by one in this cassette. Transfer robot (not shown).

The laser oscillation device 40 is a pulse laser device for generating a processing ultraviolet laser beam at a desired timing, and can be an excimer laser for emitting a laser beam LB having a wavelength of 308 nm in a pulse shape. This laser oscillation device 40 is operated at an oscillation frequency of, for example, about several tens of kHz.

The irradiation control device 50 is provided at the processing station 1
Based on the respective acceleration signals output from the three vibration sensors 58a to 58c, which are a plurality of sensor units provided at appropriate locations such as 0, whether the positional deviation amount of the processing position on the workpiece W has exceeded a predetermined allowable value. Evaluate whether or not. In addition, the irradiation control device 50 prohibits the emission of pulse light from the laser oscillation device 40 when the irradiation control device 50 evaluates that the above-mentioned displacement amount exceeds a predetermined allowable value.

The main controller 60 comprises a computer or the like, and exchanges information with the processing station 10, the loader device 20, the unloader device 30, the irradiation control device 50, etc. Control behavior.

FIG. 2 is a block diagram for explaining the configuration of the irradiation controller 50 and the like shown in FIG. As is apparent from the drawing, the irradiation control device 50 includes the vibration sensors 58a to 58a.
An evaluation unit 52 which is an evaluation unit for evaluating whether or not the positional shift amount of the processing position on the workpiece W is equal to or more than a predetermined allowable value based on the acceleration signal from the evaluation unit 8c;
2, the operation control unit 5 is an operation control unit for prohibiting the laser oscillation device 40 from emitting pulsed light when it is evaluated that the positional deviation amount exceeds a predetermined allowable value.
3 is provided.

The evaluation section 52 individually monitors acceleration signals from the vibration sensors 58a to 58c based on an instruction from the main control device 60. As will be described later in detail, the evaluation section 52 integrates each acceleration signal to A displacement signal indicating the displacement of the XY stage 12, the scanning optical system 16, and the laser oscillator 40 from the reference position is calculated. Evaluation unit 5
2 represents each displacement amount signal calculated in this way to each part 1
A comparison is made with a limit value signal indicating the upper limit of the displacement allowed at 2, 16, and 40. Further, when any of the displacement signals exceeds the predetermined limit value, the evaluation unit 52 outputs a prohibition request signal FS requesting a temporary prohibition of the irradiation of the laser beam LB to the operation control unit 53. I do. This limit value can be rewritten from main controller 60,
It can be corrected to an appropriate value according to a change in setting of conditions such as processing accuracy.

The operation control unit 53 outputs a trigger signal to the laser oscillator 40 to generate a laser beam LB, and a frequency for setting the frequency of the trigger signal output from the trigger signal generation unit 53a. The apparatus includes a setting unit 53b and a pulse number setting unit 53c for setting the number of trigger signals output from the trigger signal generation unit 53a.

Here, the trigger signal generating section 53a is configured to output the frequency setting section 5 based on a command signal from the main controller 60.
A group of trigger signals is output to the laser oscillation device 40 at the frequency and the frequency set in the pulse number setting unit 53c and the pulse number setting unit 53c, respectively. Thereby, the XY stage 12 of FIG.
A processing hole H such as a through hole can be formed on the upper workpiece W. At this time, when the prohibition request signal FS is input from the evaluation unit 52, the trigger signal generation unit 53a does not output a trigger signal to the laser oscillation device 40. That is, the trigger signal generator 53a temporarily inhibits the operation of the laser oscillation device 40. However, if the output of the group of trigger signals has already started, the output of the trigger signal is not stopped. Until the input of the inhibition request signal FS is released, the next group of trigger signals is not output to the laser oscillation device 40 even if the command signal is input from the main control device 60.
Note that the trigger signal generating unit 53a is
When the trigger signal is output to the main controller 60, a trigger signal output confirmation signal is sent back to the main controller 60 as confirmation.
Thereby, main controller 60 causes machining hole H
Has been formed, or whether the formation of the machined hole H has not been completed yet.

The main control unit 60 includes a loader driving unit 20a for controlling the operation of the transfer robot and the like provided in the loader device 20.
Also, a command signal for instructing an operation to an unloader driving unit 30a that controls the operation of the transfer robot or the like provided in the unloader device 30 is output, and these driving units 20a,
A response signal notifying the completion of the operation or the like is received from 30a. The main control device 60 includes a stage control unit 14a provided in the stage drive device 14 in the processing station 10.
A signal is transmitted and received between and. As described above, the processed work W on the XY stage 12 can be carried out of the processing station 10 and stored in the cassette in the unloader device 30, and the unprocessed work W can be taken out from the cassette in the loader device 20. Processing station 10
And placed on the XY stage 12.

The main controller 60 outputs a command signal for instructing an operation to a scanner driver 16a for controlling the operation of a galvano scanner or the like provided in the scanning optical system 16 of the processing station 10, and the scanner driver 16a And a response signal for notifying the operating state and the like. Further, main controller 60 outputs a command signal for instructing the operation to trigger signal generating section 53a and the like of operation control section 53, and receives an output confirmation signal indicating completion of output of the trigger signal from trigger signal generating section 53a. . Thereby, the processing holes H can be formed in a desired arrangement on the work W on the XY stage 12. Since the work W is wider than the irradiation range of the laser beam LB by the scanning optical system 16, the work hole H is formed for each irradiation area while the work W is appropriately step-moved by the stage driving device 14, and this is repeated. Processing holes H having a desired distribution can be formed on the entire work W.

FIG. 3 is a block diagram conceptually illustrating the circuit structure of the evaluation unit 52 shown in FIG. This evaluation unit 52
Is the acceleration signal AC from each of the vibration sensors 58a to 58c.
A displacement calculation circuit 52 that outputs displacement amount signals DS obtained by performing second-order integration on each of a to ACc.
a to 52c, a limit value storage unit 52f for storing a limit value of the displacement amount of each of the units 12, 16, 40 set corresponding to an allowable value of the displacement of the laser beam LB, and a displacement calculation circuit 52a to 52c. Prohibition determination processing unit 52g that compares each displacement amount signal DS from the controller with the limit value signal MS read from the limit value storage unit 52f to determine whether output of the trigger signal to the laser transmitting device 40 should be prohibited. And

The displacement calculating circuit 52a includes a vibration sensor 5
XY stage 1 by integrating acceleration signal ACa from
A speed estimation processing section 81 for calculating a speed signal VS corresponding to the speed No. 2 and a displacement signal DS corresponding to the displacement of the XY stage 12 by integrating the speed signal VS thus obtained.
Is calculated. Note that the displacement estimation processing unit 82 stores the reference position of the XY stage 12 in advance or updates it at an appropriate timing, and obtains a difference between this reference position and a position obtained by integrating the speed signal VS to obtain the displacement. The amount signal DS is used. Also, the acceleration signal A
Ca includes components related to the three-dimensional directions X, Y, and X. As a result of integrating these components, the displacement amount signal DS output from the displacement calculation circuit 52a also includes the three-dimensional directions X, Y, and X.
Contains components for Y and X.

Other misalignment calculation circuits 52b, 52c
Also has a structure similar to that of the displacement calculation circuit 52a, and includes a speed estimation processing unit and a displacement estimation processing unit, although detailed description is omitted.

The limit value storage section 52f stores each vibration sensor 58
The limit values set for each of a to 58c are individually stored. Each limit value signal MS output from the limit value storage unit 52f corresponding to these limit values corresponds to an allowable value of the displacement of the laser beam LB. That is, each vibration sensor 58
a to 58c (that is, the XY stage 12, the scanning optical system 1)
6, and the laser oscillation device 40) are the limit value signal MS.
When the laser beam LB is displaced by an amount corresponding to the above, the laser beam LB is incident with a positional shift just by an allowable value. By storing the limit value of the displacement amount for each of the vibration sensors 58a to 58c, the allowable amount of the displacement of the XY stage 12, the allowable amount of the displacement of the scanning optical system 16, and the allowable amount of the displacement of the laser oscillation device 40 are stored. Can be set individually. This takes into account that the degree to which each displacement amount of the XY stage 12, the scanning optical system 16, and the laser oscillation device 40 affects the displacement amount of the incident position is different from each other.

The output prohibition determination processing section 52g compares the displacement signal DS read from each of the displacement calculation circuits 52a to 52c with the limit signal MS read from the limit storage section 52f. As a result of the comparison, when it is evaluated that the displacement amount indicated by any of the displacement amount signals DS is larger than the allowable value indicated by the limit value signal MS, the output prohibition determination processing unit 52g
Is a prohibition request signal FS requesting the stop of the output of the trigger signal.
Is output to the trigger signal generator 53a of FIG.

Hereinafter, the operation of the laser processing apparatus shown in FIGS. 1 to 3 will be described. First, an unprocessed work W is loaded from the loader device 20 to the processing station 10 based on an instruction from the main control device 60. Next, based on an instruction from the main controller 60, while operating the laser oscillation device 40, a laser beam LB is incident on a proper position of the work W on the XY stage 12 of the processing station 10, and a processing hole H is formed therein. Form. More specifically, the XY stage 12 is moved so that a specific section on the work W becomes an irradiation area of the scanning optical system. Next, the processing holes H are formed in a specific arrangement on the work W in a desired arrangement by the scanning optical system 16. Next, the XY stage 12 is moved so that the section adjacent to the specific section becomes the irradiation area of the scanning optical system 16. Next, the scanning optical system 16
Thereby, the processing holes H are formed in the above-mentioned adjacent sections on the work W in a desired arrangement. By repeating the above operation, a processing hole H is formed at an appropriate position on the entire surface of the work W. Finally, based on an instruction from the main control device 60, the processed work W is discharged from the processing station 10 to the unloader device 30.

When forming the processing hole H in the processing station 10, the evaluation unit 52 constantly detects acceleration signals from vibration sensors 58a to 58c provided at appropriate places such as the processing station 10. When the evaluation unit 52 evaluates that the positional deviation amount of the processing position on the workpiece W exceeds a predetermined allowable value based on these acceleration signals, the evaluation unit 52 outputs a prohibition request signal FS for prohibiting the output of the trigger signal to the trigger signal generation unit. 53a, and the trigger signal generation unit 53a
The emission of the laser beam LB from 0 is stopped. Thus, it is possible to prevent the processing hole H from being formed with a positional deviation larger than the allowable error. Then, the evaluation unit 5
When it is determined that the positional deviation amount of the processing position on the work W has returned within the range of the predetermined allowable value, the output of the inhibition request signal FS is stopped. As a result, the trigger signal generation unit 53a sends the laser beam L to the laser oscillation device 40.
The emission of B is restarted.

FIG. 4 is a diagram schematically illustrating the mechanical distortion generated when an external force is applied to the upper portion of the processing station 10 and the positional deviation of the processing position. The frame 10a of the processing station 10 in the normal state is subjected to an external force (for example, X
Direction), the frame 10a
The scanning optical system 16 disposed at the top is the XY stage 1
2, the processing hole H is not formed at the original position by the laser beam LB, and the laser beam LB ′ having the position deviation enters the workpiece W. In this case, the evaluation unit 52 shown in FIG.
, A prohibition request signal FS is output, and the emission of the laser beam LB from the laser oscillation device 40 is prohibited.

[Second Embodiment] Hereinafter, a laser processing apparatus according to a second embodiment will be described. The laser processing apparatus according to the second embodiment includes an evaluation unit 5 of the laser processing apparatus according to the first embodiment.
2 is modified, and only the changed part will be described.

FIG. 5 shows an evaluation unit 15 of the apparatus according to the second embodiment.
2 is a block diagram conceptually illustrating a circuit structure of FIG. The evaluation unit 152 generates the displacement signal DS by integrating the acceleration signals ACa to ACc from the respective vibration sensors 58a to 58c in the second order.
2a to 52c, an allowable value storage unit 152f for storing an allowable value of the displacement of the laser beam LB, and the displacement signal DSS from the displacement calculation circuits 52a to 52c by appropriately converting the displacement signal TSS. The position shift amount signal TSS and the allowable value storage unit 152f are generated.
And an output prohibition determination processing unit 152g for comparing the position deviation allowable value signal AS read from the output unit 152 with the output deviation determination unit 152g.

Here, the permissible value storage unit 152f stores the permissible value of the positional deviation of the laser beam LB, that is, the error of the processing position permitted in design as it is. This allowable value can be appropriately changed according to the processing accuracy required for the processing hole H.

The output prohibition determination processing section 152g includes a pair of relative displacement calculation sections 152m for calculating a pair of relative displacement signals RDS based on the respective displacement amount signals DS read from the respective displacement calculation circuits 52a to 52c. A converter 152n for converting the pair of relative displacement signals RDS calculated by the displacement calculator 152m into a pair of displacement conversion signals CS corresponding to the displacement components of the incident position of the laser beam LB, and outputting the converted signals; An adder 152p for adding the shift conversion signal CS to calculate a shift amount signal TSS corresponding to a total shift amount expected when the laser beam LB is irradiated; and a shift amount signal TSS output from the adder 152p. Comparing section 1 with position error signal AS read out from allowable value storage section 152f
52q.

Here, the relative displacement calculator 152m calculates a difference between the displacement amounts with reference to the scanning optical system 16, thereby obtaining a relative displacement signal corresponding to the relative displacement amount between the XY stage 12 and the laser oscillator 40. Detect RDS.
The conversion unit 152n is generated by how much the relative displacement of the XY stage 12 and the laser oscillation device 40 changes the incident position of the laser beam LB, that is, the relative displacement of the XY stage 12 and the laser oscillation device 40. The conversion signal CS corresponding to the displacement component of the processing position considered to be calculated is calculated. The adder 152p adds the conversion signal CS to generate a displacement amount signal TSS corresponding to the final displacement amount of the processing position. When the comparing unit 152q evaluates that the displacement amount signal TSS is larger than the allowable value signal AS, the comparing unit 152q outputs a prohibition request signal FS requesting the stop of the output of the trigger signal to the trigger signal generating unit 53a (see FIG. 2).

Although the present invention has been described with reference to the embodiment, the present invention is not limited to the above embodiment.
For example, the laser processing apparatus of the present invention is not limited to a laser drill machine, but can be applied to various apparatuses including a laser annealing apparatus and the like.

In the above embodiment, the vibration sensor 58
Although a three-dimensional vibration is detected by a to 58c,
If the vibration affecting machining accuracy is limited to a specific direction,
A vibration sensor having sensitivity only in the specific direction can be used. In this case, it is sufficient to detect displacement only in the specific direction.

In the above embodiment, the vibration sensor 58
Although a to 58c are provided at three locations, when vibrations affecting the processing accuracy occur independently at four or more locations, vibration sensors are arranged at each location. Conversely, if vibrations that affect machining accuracy occur independently in only two locations,
It is sufficient to dispose the vibration sensors at both locations.

[0041]

As is apparent from the above description, according to the laser processing apparatus of the present invention, the evaluation means separates the vibrations at a plurality of locations which affect the displacement of the predetermined processing position by the plurality of sensor means. Based on the detection result, it is evaluated whether or not the displacement amount exceeds a predetermined allowable value.Therefore, it is possible to monitor the state of occurrence of the displacement by taking into account vibrations at important points of the laser processing apparatus. it can. Further, the operation control means controls the operation of the processing light irradiation means to temporarily irradiate the processing light when the evaluation means evaluates that the displacement amount exceeds the predetermined allowable value. Therefore, it is possible to prevent the laser processing from being performed in a state where the amount of displacement is large while taking into account the vibration situation at a key point of the laser processing apparatus, and to reliably prevent the occurrence of the displacement of the processing hole. it can.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a structure of a laser processing apparatus according to a first embodiment.

FIG. 2 is a block diagram illustrating a configuration of a control system of the laser processing apparatus of FIG.

FIG. 3 is a functional block diagram conceptually illustrating a circuit structure of an evaluation unit shown in FIG.

FIG. 4 is a diagram for explaining the operation of FIG. 1;

FIG. 5 is a diagram illustrating a main structure of a laser processing apparatus according to a second embodiment.

[Explanation of symbols]

 Reference Signs List 10 processing station 12 stage 14 stage driving device 14a stage control unit 16 scanning optical system 16a scanner driving unit 20 loader device 20a loader driving unit 30 unloader device 30a unloader driving unit 35c pulse number setting unit 40 laser oscillation device 50 irradiation control device 52 evaluation Unit 53 Operation control unit 53a Trigger signal generation unit 53b Frequency setting unit 58a to 58c Vibration sensor 60 Main control unit ACa to ACc Acceleration signal MS Limit value signal DS Displacement signal FS Prohibition request signal VS Speed signal W Workpiece H Hole LB Laser beam

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) G01P 15/18 B23K 101: 42 B23K 101: 42 G01P 15/00 K

Claims (4)

[Claims] 1. A processing light irradiating means for irradiating a predetermined processing position on a workpiece with processing light, a plurality of sensor means for individually detecting vibrations at a plurality of positions which affect the displacement of the predetermined processing position, Evaluation means for evaluating whether or not the positional shift amount of the predetermined processing position exceeds a predetermined allowable value based on the vibration detected by the plurality of sensor means; and A laser processing apparatus comprising: an operation control unit that controls an operation of the processing light irradiation unit and temporarily prohibits the irradiation of the processing light when it is evaluated that the processing light irradiation unit exceeds a predetermined allowable value. 2. The method according to claim 1, wherein the plurality of sensor units are acceleration sensors that respectively detect vibrations at the plurality of locations as acceleration signals, and the evaluation unit integrates each of the acceleration signals from the plurality of sensor units. 2. The laser processing apparatus according to claim 1, wherein each of the obtained displacement amount signals is evaluated by comparing the obtained displacement amount signal with a limit value corresponding to the predetermined allowable value. 3. The method according to claim 1, wherein the evaluating means calculates relative displacements of the plurality of locations based on the vibrations detected by the plurality of sensor means, and directly evaluates the displacement amount caused by the relative displacements. The laser processing device according to claim 1, wherein 4. A processing light irradiating means further comprising a stage for supporting and moving the work, wherein the processing light irradiating means includes a light source and an irradiation optical system for causing the processing light from the light source to enter the processing position. The sensor means includes three sensor units that individually detect the vibrations at the plurality of locations provided separately on the light source, the irradiation optical system, and the stage as an acceleration signal, and the evaluation means includes the three sensors. The method according to claim 1, further comprising: evaluating whether or not the displacement amount exceeds the predetermined allowable value based on the acceleration signals respectively corresponding to the light source, the irradiation optical system, and the stage from a unit. 2. The laser processing apparatus according to 1.