JP7106447B2 - Laser processing equipment - Google Patents

Description

The technology disclosed herein relates to a laser processing apparatus, such as a laser marking apparatus, that performs processing by irradiating a laser beam onto a workpiece.

Conventionally, a laser processing apparatus capable of measuring a distance to a workpiece is known.

For example, Patent Literature 1 discloses an objective condenser lens for condensing a processing laser beam (pulsed laser beam) emitted from a laser light source, and an object condenser lens and a workpiece (object to be processed). and an actuator that adjusts the focal position of the laser beam based on the measurement result of the distance sensor.

Further, in Patent Document 2, as another example of the distance measuring sensor according to Patent Document 1, a displacement sensor that emits distance measuring light (measurement laser light) for measuring the distance to a workpiece (object to be processed) is disclosed. A laser processing device with a sensor is disclosed.

The laser processing apparatus disclosed in Patent Document 2 irradiates a workpiece placed on a stage with ranging light from a displacement sensor, and appropriately detects the reflected light by the displacement sensor. It is designed to measure the distance to the workpiece.

JP-A-2006-315031 JP 2008-215829 A

By the way, in the case of a general laser processing apparatus, it is conceivable to generate a laser beam inside a housing and transmit the laser beam through an emission window provided in the housing when the laser beam is emitted.

The inventors of the present application newly came up with the idea of transmitting not only the laser beam but also the ranging light through the exit window in the laser processing apparatus as disclosed in Patent Document 2 above.

However, when the distance measuring light is transmitted through the emission window, if dust or the like adheres to the transmission window and becomes dirty, the distance measuring light may be reflected by the dust or the like. The reflected distance measurement light causes an error in distance measurement, which is inconvenient for ensuring measurement accuracy.

In addition, if the transmission window becomes dirty, the laser beam is attenuated, possibly degrading the processing performance. In order to ensure the processing performance, it is necessary to clean the transmission window periodically, and in order to appropriately determine the cleaning timing, it is desired to detect contamination of the transmission window in advance.

The technology disclosed herein has been made in view of this point, and its purpose is to suppress deterioration in measurement accuracy and processing performance due to contamination of the transmission window.

Specifically, a first aspect of the present disclosure includes an excitation light generation unit that generates excitation light, and generates laser light based on the excitation light generated by the excitation light generation unit, and emits the laser light. a laser light output unit that irradiates a work piece with the laser light emitted from the laser light output unit, and a laser light scanning unit that two-dimensionally scans the surface of the work piece; and at least the laser light output and a laser beam scanning unit provided therein; and a transmission window provided in the housing through which the laser beam two-dimensionally scanned by the laser beam scanning unit is transmitted. It depends.

Further, according to the first aspect of the present disclosure, the laser processing device is provided inside the housing, and includes distance measuring light for measuring a distance from the laser processing device to the surface of the workpiece. a distance measuring light emitting unit that emits toward the laser beam scanning unit; and a distance measuring light emitted from the distance measuring light emitting unit provided inside the housing and reflected by the workpiece. a distance measuring light receiving portion that receives light through the laser beam scanning portion; A distance measuring unit that measures a distance to a surface; A contamination detection unit that detects contamination, and an output unit that outputs a detection result of the contamination detection unit.

According to this configuration, when the laser processing apparatus processes the workpiece, the laser light output section emits the laser light. The laser light emitted from the laser light output section is applied to the workpiece through the laser light scanning section and the transmission window. The workpiece can be processed by scanning the laser beam irradiated onto the workpiece.

On the other hand, according to the above configuration, when measuring the distance from the laser processing device to the surface of the workpiece, the distance measuring light emitting section emits the distance measuring light. The distance measuring light emitted from the distance measuring light emitting section is irradiated onto the workpiece through the laser light scanning section and the transmission window. After being reflected by the workpiece, the distance measuring light irradiated to the workpiece passes through the transmission window again, returns to the laser beam scanning section, and reaches the ranging light receiving section. The distance measuring section measures the distance to the surface of the workpiece based on the light receiving position of the distance measuring light receiving section.

Here, if the transmission window is dirty, the range-finding light receiving section receives the distance-measuring light reflected by the surface of the workpiece, instead of or in addition to the range-finding light, by the transmission window. The reflected distance measuring light is received.

Here, the distance to the transmission window does not change regardless of the type of workpiece. Therefore, the light receiving position caused by the contamination of the transmission window can be estimated in advance.

Therefore, for example, by considering the location of each light receiving position, the dirt detection unit can identify the distance measuring light caused by the light reflected by the transmission window among the distance measuring light received by the distance measuring light receiving unit. can. As a result, the dirt detection section can detect dirt on the transmissive window.

The result of detection by the contamination detection section is output by the output section. The output destination of the output unit may be a display unit such as a display, or may be a control unit such as a PLC. In any case, by outputting the result of detection by the contamination detection unit, it is possible to prompt the user to replace or clean the transmission window, or to execute processing in consideration of the presence or absence of contamination. This makes it possible to suppress deterioration in measurement accuracy and processing performance due to contamination of the transmission window.

Further, according to the second aspect of the present disclosure, the transmissive window is arranged at a reference position where the optical path length between it and the distance measuring light emitting unit is known, and the dirt detection unit detects the distance measuring light Dirt on the transmissive window may be detected based on the state of light reception at a light receiving position corresponding to the reference position among the light receiving positions of the distance measuring light in the light receiving unit.

According to this configuration, dirt on the transmission window can be detected based on the state of light reception (for example, the magnitude of the amount of light received) at the light reception position corresponding to the reference position.

Further, according to the third aspect of the present disclosure, the distance measuring light receiving section is configured to detect the amount of light received, and the dirt detection section detects the amount of light received at the light receiving position corresponding to the reference position. and detecting the degree of contamination in the transmission window.

According to this configuration, it is possible to more appropriately detect the degree of dirt on the transmission window.

Further, according to the fourth aspect of the present disclosure, the dirt detection unit compares the amount of light received at the light receiving position corresponding to the reference position with a preset threshold value, and the amount of light received is If the threshold value is exceeded, it may be determined that the transmission window is dirty.

According to this configuration, it is possible to more appropriately detect the degree of dirt on the transmission window.

Further, according to the fifth aspect of the present disclosure, the laser processing apparatus may include a history storage unit that is connected to the output unit and stores time transition of detection results by the dirt detection unit.

According to this configuration, it is possible to store the temporal transition of the detection result and provide the stored contents to the user. This allows the user to know when to replace or clean the transmission window, for example. This improves usability of the laser processing apparatus.

As described above, according to the laser processing apparatus, deterioration in measurement accuracy and processing performance due to contamination of the transmission window can be suppressed.

FIG. 1 is a diagram illustrating the overall configuration of a laser processing system. FIG. 2 is a block diagram illustrating the schematic configuration of the laser processing apparatus. FIG. 3A is a block diagram illustrating a schematic configuration of a marker head; FIG. 3B is a block diagram illustrating a schematic configuration of the marker head; FIG. 4 is a perspective view illustrating the appearance of the marker head. FIG. 5 is a perspective view illustrating the configuration of a laser beam scanning unit. FIG. 6 is a diagram illustrating the configurations of the laser light guide section, the laser light scanning section, and the distance measuring unit. FIG. 7 is a cross-sectional view illustrating an optical path connecting a laser beam guiding section, a laser beam scanning section, and a distance measuring unit. FIG. 8 is a perspective view illustrating an optical path connecting a laser beam guide section, a laser beam scanning section, and a distance measuring unit. FIG. 9 is a cross-sectional view illustrating the configuration of a transmissive window. FIG. 10 is a diagram for explaining the triangulation method. FIG. 11 is a flowchart illustrating a procedure for machining a workpiece. FIG. 12 is a diagram for explaining contamination of the transmission window. FIG. 13A is a diagram illustrating reflection of distance measuring light by a transmission window. FIG. 13B is a diagram exemplifying a received light waveform of reflected light by a transmission window. FIG. 14 is a flowchart exemplifying processing related to dirt determination of a transmissive window. FIG. 15 is a diagram illustrating a display mode of various information including dirt determination. FIG. 16 is a diagram illustrating the time transition of contamination determination. FIG. 17 is a diagram exemplifying a notification mode of contamination determination. FIG. 18 is a diagram exemplifying threshold settings for contamination determination.

Hereinafter, embodiments of the present disclosure will be described based on the drawings. Note that the following description is an example.

That is, in this specification, a laser marker will be described as an example of a laser processing apparatus, but the technology disclosed herein can be applied to general laser application equipment regardless of the names of laser processing apparatus and laser marker.

In this specification, printing processing will be described as a representative example of processing, but the present invention is not limited to printing processing, and can be used in any processing processing using laser light, such as image marking.

<Overall composition>
FIG. 1 is a diagram illustrating the overall configuration of a laser processing system S, and FIG. 2 is a diagram illustrating a schematic configuration of a laser processing device L in the laser processing system S. As shown in FIG. A laser processing system S illustrated in FIG. 1 includes a laser processing device L, an operation terminal 800 and an external device 900 connected thereto.

1 and 2 irradiates a laser beam emitted from the marker head 1 onto a workpiece W as an object to be processed, and three-dimensionally scans the surface of the workpiece W. Processing is performed by The term "three-dimensional scanning" as used herein refers to a two-dimensional operation (so-called "two-dimensional scanning") of scanning the surface of the workpiece W with the irradiation target of the laser beam, and adjusting the focal position of the laser beam. It refers to the general concept of a combination of one-dimensional motion and

In particular, the laser processing apparatus L according to this embodiment can emit a laser beam having a wavelength of around 1064 nm as a laser beam for processing the workpiece W. This wavelength corresponds to the near infrared (Near-InfraRed: NIR) wavelength range. Therefore, in the following description, the laser beam for processing the workpiece W may be referred to as "near-infrared laser beam" to distinguish it from other laser beams. Laser beams other than near-infrared rays may be used for processing the workpiece W.

In addition, the laser processing apparatus L according to the present embodiment measures the distance to the workpiece W via the distance measuring unit 5 incorporated in the marker head 1, and uses the measurement result to emit near-infrared laser light. Focus position can be adjusted.

As shown in FIGS. 1 and 2 , the laser processing apparatus L includes a marker head 1 for emitting laser light and a marker controller 100 for controlling the marker head 1 .

The marker head 1 and the marker controller 100 are separated in this embodiment, electrically connected via electrical wiring, and optically coupled via an optical fiber cable.

More generally, one of the marker head 1 and the marker controller 100 can be integrated into the other. In this case, the optical fiber cable or the like can be omitted as appropriate.

The operation terminal 800 has, for example, a central processing unit (CPU) and memory, and is connected to the marker controller 100 . This operation terminal 800 functions as a terminal for setting various processing conditions such as print settings and for displaying information related to laser processing to the user. This operation terminal 800 includes a display unit 801 for displaying information to the user, an operation unit 802 for receiving operation input by the user, and a storage device 803 for storing various information.

Specifically, the display unit 801 is configured by, for example, a liquid crystal display or an organic EL panel. The display unit 801 displays the operation status of the laser processing apparatus L, processing conditions, and the like as information related to laser processing. On the other hand, the operation unit 802 is composed of, for example, a keyboard and/or pointing device. Here, the pointing device includes a mouse and/or a joystick. The operation unit 802 is configured to receive an operation input by the user, and is used to operate the marker head 1 via the marker controller 100 .

The operation terminal 800 configured as described above can set the processing conditions for laser processing based on the operation input by the user. The processing conditions include, for example, the contents of a character string to be printed on the workpiece W (marking pattern), the output required for the laser beam (target output), and the scanning speed of the laser beam on the workpiece W (scanning speed ) is included.

The processing conditions according to the present embodiment also include the conditions and parameters related to the distance measurement unit 5 (hereinafter also referred to as "distance measurement conditions"). Such distance measurement conditions include, for example, data that associates a signal indicating the detection result by the distance measurement unit 5 with the distance to the surface of the workpiece W, and the like.

The processing conditions set by the operating terminal 800 are output to the marker controller 100 and stored in the condition setting storage section 102 thereof. If necessary, the storage device 803 in the operation terminal 800 may store the processing conditions.

Note that the operation terminal 800 can be integrated into the marker controller 100, for example. In this case, the term "control unit" is used instead of "operation terminal", but at least in the present embodiment, the operation terminal 800 and the marker controller 100 are separated from each other.

The external device 900 is connected to the marker controller 100 of the laser processing device L as required. In the example shown in FIG. 1, an image recognition device 901 and a programmable logic controller (PLC) 902 are provided as the external device 900 .

Specifically, the image recognition device 901 determines the type and position of the work W conveyed on the line, for example. For example, an image sensor can be used as the image recognition device 901 . PLC 902 is used to control laser processing system S according to a predetermined sequence.

In addition to the devices and devices described above, the laser processing device L can also be connected to a device for operation and control, a computer for performing various other processes, a storage device, peripheral devices, and the like. The connection in this case may be serial connection such as IEEE1394, RS-232, RS-422 and USB, or parallel connection, for example. Alternatively, electrical, magnetic, or optical connections can be employed through networks such as 10BASE-T, 100BASE-TX, 1000BASE-T, and the like. In addition to the wired connection, a wireless LAN such as IEEE802, or a wireless connection using radio waves such as Bluetooth (registered trademark), infrared rays, optical communication, or the like may be used. Furthermore, various memory cards, magnetic disks, magneto-optical disks, semiconductor memories, hard disks, etc., can be used as storage media used in storage devices for exchanging data and storing various settings.

The hardware configurations of the marker controller 100 and the marker head 1 and the configuration of the marker head 1 controlled by the marker controller 100 will be sequentially described below.

<Marker controller 100>
As shown in FIG. 2, the marker controller 100 includes a condition setting storage unit 102 for storing the processing conditions described above, a control unit 101 for controlling the marker head 1 based on the processing conditions stored therein, a laser excitation and an excitation light generator 110 that generates light (excitation light).

(Condition setting storage unit 102)
The condition setting storage unit 102 is configured to store processing conditions set via the operation terminal 800 and to output the stored processing conditions to the control unit 101 as necessary.

Specifically, the condition setting storage unit 102 is configured using a volatile memory, a nonvolatile memory, a hard disk drive (HDD), or the like, and temporarily or continuously stores information indicating processing conditions. can do. Note that when the operation terminal 800 is incorporated in the marker controller 100, the storage device 803 can be configured to also serve as the condition setting storage section 102. FIG.

(control unit 101)
Based on the processing conditions stored in the condition setting storage unit 102, the control unit 101 controls at least the excitation light generation unit 110 in the marker controller 100, the laser light output unit 2 in the marker head 1, the laser light guide unit 3, By controlling the laser beam scanning unit 4 and the distance measuring unit 5, the printing process of the workpiece W and the like are executed.

Specifically, the control unit 101 has a CPU, a memory, and an input/output bus, and receives signals indicating information input via the operation terminal 800 and processing conditions read from the condition setting storage unit 102. A control signal is generated based on the indicated signal. The control unit 101 outputs the control signal thus generated to each unit of the laser processing apparatus L, thereby controlling the printing processing on the work W and the measurement of the distance to the work W. FIG.

For example, when starting machining of the workpiece W, the control unit 101 reads the target output stored in the condition setting storage unit 102, outputs a control signal generated based on the target output to the excitation light source driving unit 112, Controls the generation of laser excitation light.

(Excitation light generator 110)
The excitation light generation unit 110 is optically coupled to the excitation light source 111 that generates laser light according to the drive current, the excitation light source drive unit 112 that supplies the drive current to the excitation light source 111 , and the excitation light source 111 . and an excitation light condensing unit 113 . The excitation light source 111 and the excitation light collector 113 are fixed in an excitation casing (not shown). Although details are omitted, the excitation casing is made of a metal such as copper having excellent thermal conductivity, and can efficiently dissipate heat from the excitation light source 111 .

Each part of the excitation light generator 110 will be described in order below.

The excitation light source drive section 112 supplies drive current to the excitation light source 111 based on the control signal output from the control section 101 . Although details are omitted, the excitation light source driving section 112 determines the drive current based on the target output determined by the control section 101 and supplies the determined drive current to the excitation light source 111 .

The excitation light source 111 is supplied with a driving current from the excitation light source driving section 112 and oscillates laser light according to the driving current. For example, the excitation light source 111 is composed of a laser diode (LD) or the like, and an LD array or LD bar in which a plurality of LD elements are arranged in a straight line can be used. When an LD array or an LD bar is used as the excitation light source 111 , laser light emitted from each element is linearly output and enters the excitation light collecting section 113 .

The excitation light collector 113 collects the laser light output from the excitation light source 111 and outputs it as laser excitation light (excitation light). For example, the excitation light condensing unit 113 is configured by a focusing lens or the like, and has an incident surface on which laser light is incident and an emission surface from which the laser excitation light is output. The excitation light condensing section 113 is optically coupled to the marker head 1 via the aforementioned optical fiber cable. Therefore, the laser excitation light output from the excitation light focusing section 113 is guided to the marker head 1 via the optical fiber cable.

The excitation light generator 110 can be an LD unit or an LD module in which the excitation light source driver 112, the excitation light source 111 and the excitation light collector 113 are incorporated in advance. In addition, the excitation light emitted from the excitation light generator 110 (specifically, the laser excitation light emitted from the excitation light collector 113) can be unpolarized. There is no need to consider this, which is advantageous in terms of design. In particular, regarding the configuration around the excitation light source 111, the LD unit itself, which bundles and outputs the light obtained from each LD array in which several tens of LD elements are arranged, with an optical fiber, has a mechanism for making the output light unpolarized. It is preferable to have

(other components)
The marker controller 100 also has a distance measuring section 103 that measures the distance to the work W via the distance measuring unit 5 . The distance measuring unit 103 is electrically connected to the distance measuring unit 5, and is a signal related to the measurement result by the distance measuring unit 5 (at least, a signal indicating the light receiving position of the distance measuring light by the distance measuring light receiving unit 5B). can be received.

The signal output from the distance measuring unit 5 basically corresponds to the distance to the surface of the workpiece W. However, if the transmission window 19 is dirty, for example, a signal corresponding to the distance to the surface of the transmission window 19 may be detected in addition to the signal corresponding to the distance to the surface of the workpiece W. Here, the transmission window 19 refers to a window portion for emitting the near-infrared laser light generated and amplified inside the marker head 1 to the outside.

Therefore, the marker controller 100 according to the present embodiment includes a dirt detection section 104 for detecting dirt on the transmission window 19 . A result of detection by the contamination detection unit 104 can be output to the distance measurement unit 103 , the operation terminal 800 and/or the external device 900 via the output unit 105 .

The distance measuring section 103 according to this embodiment is connected to the distance measuring unit 5 via the dirt detecting section 104 .

Note that the distance measurement unit 103 , the dirt detection unit 104 and the output unit 105 may be configured by the control unit 101 . For example, the control unit 101 may also serve as the distance measurement unit 103 . Alternatively, the distance measurement unit 103 may also serve as the dirt detection unit 104 and/or the output unit 105 .

Details of the distance measurement unit 103, the dirt detection unit 104, and the output unit 105 will be described later.

<Marker head 1>
As described above, the laser excitation light generated by the excitation light generator 110 is guided to the marker head 1 via the optical fiber cable. The marker head 1 includes a laser light output unit 2 that amplifies, generates and outputs laser light based on laser excitation light, and a laser light output unit 2 that irradiates the surface of the workpiece W with the laser light output 2 . A laser light scanning unit 4 that performs dimensional scanning, a laser light guide unit 3 that forms an optical path from the laser light output unit 2 to the laser light scanning unit 4, and distance measurement that emits light and receives light through the laser light scanning unit 4. and a distance measuring unit 5 for measuring the distance to the surface of the work W based on light.

Here, the laser light guide unit 3 according to the present embodiment not only configures an optical path, but also includes a Z scanner (focus adjustment unit) 33 that adjusts the focal position of the laser light, and a guide light source that emits guide light. A plurality of members such as (guide light emitting portion) 36 are combined.

In addition, the laser light guide section 3 further includes an upstream merging mechanism 31 for merging the near-infrared laser light output from the laser light output section 2 and the guide light output from the guide light source 36, and the laser light scanning section 4. It has a downstream merging mechanism 35 for merging the guided laser light and the distance measuring light projected from the distance measuring unit 5 .

3A and 3B are block diagrams illustrating the schematic configuration of the marker head 1, and FIG. 4 is a perspective view illustrating the appearance of the marker head 1. FIG. 3A to 3B, FIG. 3A illustrates the case of processing the work W using a near-infrared laser beam, and FIG. 3B illustrates the case of measuring the distance to the surface of the work W using the distance measuring unit 5. is exemplified.

As illustrated in FIGS. 3A to 4, the marker head 1 includes a housing 10 in which at least a laser light output section 2, a laser light guide section 3, a laser light scanning section 4, and a distance measuring unit 5 are provided. ing. The housing 10 has a substantially rectangular parallelepiped shape as shown in FIG. The lower surface of the housing 10 is defined by a plate-like bottom plate 10a. The bottom plate 10a is provided with a transmission window 19 for emitting laser light from the marker head 1 to the outside of the marker head 1. As shown in FIG. The transmission window 19 is configured by fitting a plate-like member capable of transmitting near-infrared laser light, guide light, and range-finding light into a through-hole extending through the bottom plate 10a in the plate thickness direction.

In the description below, the longitudinal direction of the housing 10 in FIG. It may be called "left and right direction". Similarly, the height direction of the housing 10 in FIG. 4 may be simply referred to as "height direction" or "vertical direction".

FIG. 5 is a perspective view illustrating the configuration of the laser beam scanning unit 4. As shown in FIG. 6 is a cross-sectional view illustrating the configuration of the laser light guide section 3, the laser light scanning section 4 and the distance measuring unit 5, and FIG. 8 is a perspective view illustrating an optical path connecting the laser light guide section 3, the laser light scanning section 4, and the distance measuring unit 5. FIG.

As illustrated in FIGS. 5 and 6, a partition 11 is provided inside the housing 10 . The internal space of the housing 10 is partitioned into one side and the other side in the longitudinal direction by the partition portion 11 .

Specifically, the partition part 11 is formed in a flat plate shape extending in a direction perpendicular to the longitudinal direction of the housing 10 . In addition, in the longitudinal direction of the housing 10, the partition section 11 is arranged closer to one side in the longitudinal direction (the front side in FIG. 4) than the central portion of the housing 10 in the same direction.

Therefore, the space partitioned on one longitudinal side in the housing 10 has a smaller longitudinal dimension than the space partitioned on the other longitudinal side (rear side in FIG. 4). Hereinafter, the space partitioned on the other longitudinal side in the housing 10 will be referred to as a first space S1, and the space partitioned on the one longitudinal side will be referred to as a second space S2.

In this embodiment, the laser light output section 2, some components of the laser light guide section 3, the laser light scanning section 4, and the distance measuring unit 5 are arranged inside the first space S1. On the other hand, main components of the laser beam guide section 3 are arranged inside the second space S2.

Specifically, the first space S1 is partitioned into a space on one side in the short direction (left side in FIG. 4) and a space on the other side (right side in FIG. 4) by a substantially flat base plate 12. . In the former space, mainly parts constituting the laser light output section 2 are arranged.

More specifically, among the parts that make up the laser light output unit 2, the optical parts 21, such as optical lenses and optical crystals, which are required to be hermetically sealed as much as possible, are arranged in the first space S1 in the transverse direction. In the side space, it is arranged inside a receiving space surrounded by a base plate 12 or the like.

On the other hand, among the parts that make up the laser light output unit 2, parts that do not necessarily need to be hermetically sealed, such as electrical wiring and a heat sink 22 shown in FIG. It is arranged on the opposite side (the other side in the short direction of the first space S1).

Further, as illustrated in FIGS. 5 and 6, the laser beam scanning unit 4 can be arranged on one side in the short direction across the base plate 12, similarly to the optical component 21 in the laser beam output unit 2. . Specifically, the laser beam scanning section 4 according to this embodiment is arranged adjacent to the partition section 11 in the longitudinal direction and along the inner bottom surface of the housing 10 in the vertical direction.

Further, as shown in FIG. 6, the distance measuring unit 5 is arranged in the space on the other side in the short direction of the first space S1, like the heat sink 22 in the laser light output section 2. As shown in FIG.

Also, the components that make up the laser beam guide section 3 are mainly arranged in the second space S2. In this embodiment, most of the components that make up the laser beam guide section 3 are housed in a space surrounded by a partition section 11 and a cover member 17 that partitions the front surface of the housing 10 .

Note that, among the components that configure the laser beam guide section 3, the downstream merging mechanism 35 is arranged in the vicinity of the partition section 11 in the first space S1 (see FIG. 5). That is, in this embodiment, the downstream merging mechanism 35 is positioned near the boundary between the first space S1 and the second space S2.

A through hole (not shown) is formed in the base plate 12 so as to penetrate the base plate 12 in the plate thickness direction. Through this through-hole, the laser light guide section 3, the laser light scanning section 4, and the distance measuring unit 5 are optically coupled.

The configurations of the laser light output section 2, the laser light guide section 3, the laser light scanning section 4, and the distance measuring unit 5 will be described in order below.

(Laser light output unit 2)
The laser light output unit 2 generates near-infrared laser light for print processing based on the laser excitation light generated by the excitation light generation unit 110, and directs the near-infrared laser light to the laser light guide unit 3. configured to output.

Specifically, the laser light output unit 2 generates a laser light having a predetermined wavelength based on the laser excitation light, and a laser oscillator 21a that amplifies the laser light and emits a near-infrared laser light. It has a beam sampler 21b for separating part of the oscillated near-infrared laser light, and a power monitor 21c into which the near-infrared laser light separated by the beam sampler 21b is incident.

Although the details are omitted, the laser oscillator 21a according to the present embodiment includes a laser medium for emitting laser light by performing stimulated emission corresponding to laser excitation light, and a laser medium for pulsating the laser light emitted from the laser medium. It has a Q switch and a mirror that resonates the laser light pulse-oscillated by the Q switch.

Particularly in this embodiment, rod-shaped Nd:YVO ₄ (yttrium vanadate) is used as the laser medium. As a result, the laser oscillator 21a can emit laser light having a wavelength of around 1064 nm (near-infrared laser light described above) as laser light. However, it is not limited to this example, and other laser media such as YAG, YLF, and GdVO ₄ doped with rare earth elements can also be used. Various solid-state laser media can be used according to the application of the laser processing apparatus L.

Also, a wavelength conversion element can be combined with the solid-state laser medium to convert the wavelength of the output laser light to an arbitrary wavelength. A so-called fiber laser, which uses a fiber as an oscillator instead of a bulk as a solid-state laser medium, may also be used.

Further, the laser oscillator 21a may be configured by combining a solid laser medium such as Nd: _YVO4 and a fiber. In that case, as in the case of using a solid-state laser medium, a laser with a short pulse width is emitted to suppress thermal damage to the workpiece W, while high output can be achieved as in the case of using a fiber. This makes it possible to achieve faster print processing.

The power monitor 21c detects the output of near-infrared laser light. The power monitor 21c is electrically connected to the marker controller 100, and can output its detection signal to the control section 101 or the like.

(Laser beam guide part 3)
The laser light guide section 3 forms an optical path P that guides the near-infrared laser light emitted from the laser light output section 2 to the laser light scanning section 4 . The laser light guide section 3 includes a bend mirror 34 for forming such an optical path P, a Z scanner (focus adjustment section) 33, a guide light source (guide light emission section) 36, and the like. All of these parts are provided inside the housing 10 (mainly in the second space S2).

The near-infrared laser light incident from the laser light output section 2 is reflected by the bend mirror 34 and passes through the laser light guide section 3 . A Z scanner 33 for adjusting the focal position of the near-infrared laser beam is arranged on the way to the bend mirror 34 . A near-infrared laser beam that passes through the Z scanner 33 and is reflected by the bend mirror 34 enters the laser beam scanning unit 4 .

The optical path P formed by the laser light guide section 3 can be divided into two with the Z scanner 33 as a focus adjustment section as a boundary. More specifically, the optical path P formed by the laser beam guide unit 3 includes an upstream optical path Pu from the laser beam output unit 2 to the Z scanner 33, a downstream optical path Pd from the Z scanner 33 to the laser beam scanning unit 4, can be divided into

More specifically, the upstream optical path Pu is provided inside the housing 10 and extends from the laser light output unit 2 to the Z scanner 33 via the above-described upstream joining mechanism 31 .

On the other hand, the downstream optical path Pd is provided inside the housing 10, and passes from the Z scanner 33, through the bend mirror 34, and the downstream merging mechanism 35 in order, to the laser beam scanning unit 4. It reaches the first scanner 41 .

As described above, inside the housing 10, the upstream joining mechanism 31 is provided in the middle of the upstream optical path Pu, and the downstream joining mechanism 35 is provided in the middle of the downstream optical path Pd.

Hereinafter, configurations related to the laser beam guide section 3 will be described in order.

- Guide light source 36 -
The guide light source 36 is provided in the second space S<b>2 inside the housing 10 and emits guide light for projecting a predetermined machining pattern onto the surface of the work W. The wavelength of this guide light is set to fall within the visible light range. As an example, the guide light source 36 according to the present embodiment emits red laser light having a wavelength of around 655 nm as guide light. Therefore, when the guide light is emitted from the marker head 1, the user can visually recognize the guide light.

In addition, in this embodiment, the wavelength of the guide light is set so as to be at least different from the wavelength of the near-infrared laser light. Further, as will be described later, the distance measuring light emitting section 5A in the distance measuring unit 5 emits distance measuring light having a wavelength different from that of the guide light and the near-infrared laser light. Therefore, the distance measuring light, the guide light, and the laser light have different wavelengths.

Specifically, the guide light source 36 is arranged at substantially the same height as the upstream merging mechanism 31 in the second space S2, and emits a visible light laser (guide light) toward the inner side of the housing 10 in the short direction. can be emitted. The guide light source 36 is also oriented such that the optical axis of the guide light emitted from the guide light source 36 intersects with the upstream joining mechanism 31 .

The term “substantially the same height” as used herein means that the height positions are substantially equal when viewed from the bottom plate 10a forming the lower surface of the housing 10. As shown in FIG. Also in other descriptions, it refers to the height seen from the bottom plate 10a.

Therefore, when guide light is emitted from the guide light source 36 in order to allow the user to visually recognize the pattern processed by the near-infrared laser light, the guide light reaches the upstream merging mechanism 31 . The upstream merging mechanism 31 has a dichroic mirror (not shown) as an optical component. As will be described later, this dichroic mirror reflects near-infrared laser light while transmitting guide light. As a result, the guide light that has passed through the dichroic mirror and the near-infrared laser light that has been reflected by the mirror merge and become coaxial.

The guide light source 36 according to this embodiment is configured to emit guide light based on the control signal output from the control section 101 .

-Upstream merging mechanism 31-
The upstream merging mechanism 31 merges the guide light emitted from the guide light source 36 as a guide light emitting part into the upstream optical path Pu. By providing the upstream merging mechanism 31, the guide light emitted from the guide light source 36 and the near-infrared laser light in the upstream optical path Pu can be made coaxial.

As described above, the wavelength of the guide light is set to be at least different from the wavelength of the near-infrared laser light. Therefore, the upstream merging mechanism 31 can be configured using, for example, a dichroic mirror as described above. The near-infrared laser light and guide light coaxialized by this dichroic mirror propagate downward, pass through the Z scanner 33 and reach the bend mirror 34 .

-Z Scanner 33-
A Z scanner 33 as a focus adjustment unit is arranged between the upstream merging mechanism 31 and the bend mirror 34, and can adjust the focal position of the near-infrared laser light emitted from the laser light output unit 2. can. The Z scanner 33 as a focus adjustment unit functions as means for vertically scanning the near-infrared laser beam.

The near-infrared laser light passing through the Z scanner 33 is coaxial with the guide light emitted from the guide light source 36 as described above. Therefore, by operating the Z scanner 33, not only the near-infrared laser light but also the focal position of the guide light can be adjusted.

Note that the Z scanner 33 according to this embodiment is configured to operate based on the control signal output from the control section 101, like the guide light source .

-Bend mirror 34-
The bend mirror 34 is provided in the middle of the downstream optical path Pd, and arranged so as to bend the optical path Pd and direct it backward. As shown in FIG. 6, the bend mirror 34 is arranged at substantially the same height as the dichroic mirror 35a in the downstream confluence mechanism 35, and reflects the near-infrared laser light and the guide light that have passed through the Z scanner 33. can be done.

The near-infrared laser light and the guide light reflected by the bend mirror 34 propagate backward, pass through the downstream confluence mechanism 35, and reach the laser light scanning section (specifically, the first scanner 41).

- Downstream merging mechanism 35 -
The downstream merging mechanism 35 guides the distance measuring light emitted from the distance measuring light emitting portion 5A in the distance measuring unit 5 to the work W via the laser beam scanning portion 4 by joining the above described downstream optical path Pd. . In addition, the downstream merging mechanism 35 guides the distance measuring light reflected by the workpiece W and returning to the laser beam scanning unit 4 and the downstream optical path Pd in that order to the distance measuring light receiving unit 5B in the distance measuring unit 5 .

By providing the downstream merging mechanism 35, the distance measuring light emitted from the distance measuring light emitting portion 5A can be coaxial with the near-infrared laser light and the guide light in the downstream optical path Pd. At the same time, by providing the downstream merging mechanism 35, of the ranging light emitted from the marker head 1 and reflected by the workpiece W, the ranging light incident on the marker head 1 is led to the ranging light receiving section 5B. be able to.

As described above, the wavelength of the ranging light is set to be different from the wavelengths of the near-infrared laser light and guide light. Therefore, the downstream merging mechanism 35 can be configured using, for example, a dichroic mirror, like the upstream merging mechanism 31 .

Specifically, the downstream joining mechanism 35 according to the present embodiment has a dichroic mirror 35a that transmits one of the distance measuring light and the guide light and reflects the other (see FIGS. 6 and 7). More specifically, the dichroic mirror 35a is arranged at substantially the same height as the bend mirror 34 and behind the bend mirror 34, and is arranged in the space on the left side of the housing 10 in the short direction.

The dichroic mirror 35a is also fixed in such a position that one mirror surface faces the bend mirror 34 and the other mirror surface faces the base plate 12, as shown in FIG. Therefore, the near-infrared laser light and the guide light are incident on one mirror surface of the dichroic mirror 35a, while the distance measuring light is incident on the other mirror surface.

The dichroic mirror 35a according to the present embodiment can reflect the distance measuring light and transmit the near-infrared laser light and the guide light. As a result, for example, when the distance measuring light emitted from the distance measuring unit 5 is incident on the dichroic mirror 35a, the distance measuring light is merged into the downstream optical path Pd and made coaxial with the near-infrared laser light and the guide light. can be done. The near-infrared laser light, guide light, and distance measuring light thus coaxialized reach the first scanner 41 as shown in FIGS. 3A and 3B.

On the other hand, the distance measuring light reflected by the workpiece W returns to the laser light scanning unit 4 and reaches the downstream optical path Pd. The distance measuring light returning to the downstream optical path P is reflected by the dichroic mirror 35 a in the downstream merging mechanism 35 and reaches the distance measuring unit 5 .

As shown in FIG. 7, the distance measuring light incident on the dichroic mirror 35a from the distance measuring unit 5 and the distance measuring light reflected by the dichroic mirror 35a and incident on the distance measuring unit 5 both The light propagates along the left-right direction (the lateral direction of the housing 10) when the housing 10 is viewed from above.

(Laser beam scanning unit 4)
As shown in FIG. 3A, the laser light scanning unit 4 irradiates the workpiece W with laser light (near-infrared laser light) emitted from the laser light output unit 2 and guided by the laser light guide unit 3. It is configured to perform two-dimensional scanning on the surface of the work W.

In the example shown in FIG. 5, the laser beam scanning unit 4 is configured as a so-called two-axis galvanometer scanner. That is, the laser beam scanning unit 4 includes a first scanner 41 for scanning the near-infrared laser beam incident from the laser beam guide unit 3 in a first direction, and a near-infrared laser beam scanned by the first scanner 41 . and a second scanner 42 for scanning light in a second direction.

Here, the second direction refers to a direction substantially orthogonal to the first direction. Therefore, the second scanner 42 can scan the near-infrared laser light in a direction substantially perpendicular to the first scanner 41 . In this embodiment, the first direction is equal to the front-rear direction (the longitudinal direction of the housing 10), and the second direction is equal to the left-right direction (the lateral direction of the housing 10).

The first scanner 41 has a first mirror 41a at its tip. The first mirror 41a is positioned at substantially the same height as the bend mirror 34 and the dichroic mirror 35a and behind the dichroic mirror 35a. Therefore, as shown in FIG. 5, the bend mirror 34, the dichroic mirror 35a, and the first mirror 41a are arranged in a line in the front-rear direction (longitudinal direction of the housing 10).

The first mirror 41 a is also rotationally driven by a motor (not shown) incorporated in the first scanner 41 . This motor can rotate the first mirror 41a around a rotation axis extending in the vertical direction. By adjusting the rotational posture of the first mirror 41a, the angle of reflection of the near-infrared laser beam by the first mirror 41a can be adjusted.

Similarly, the second scanner 42 has a second mirror 42a at its tip. The second mirror 42a is positioned at substantially the same height as the first mirror 41a in the first scanner 41 and to the right of the first mirror 41a. Therefore, as shown in FIG. 6, the first mirror 41a and the second mirror 42a are arranged side by side along the left-right direction (the lateral direction of the housing 10).

The second mirror 42a is also rotationally driven by a motor (not shown) incorporated in the second scanner 42. As shown in FIG. This motor can rotate the second mirror 42a around a rotation axis extending in the front-rear direction. By adjusting the rotational attitude of the second mirror 42a, the angle of reflection of the near-infrared laser light by the second mirror 42a can be adjusted.

Therefore, when the near-infrared laser light is incident on the laser light scanning unit 4 from the downstream joining mechanism 35, the near-infrared laser light is reflected by the first mirror 41a of the first scanner 41 and the second mirror of the second scanner 42. 42 a in order, and exits the marker head 1 through the transmission window 19 .

At this time, by operating the motor of the first scanner 41 to adjust the rotational attitude of the first mirror 41a, the surface of the work W can be scanned with the near-infrared laser light in the first direction. . At the same time, by actuating the motor of the second scanner 42 to adjust the rotational posture of the second mirror 42a, the surface of the work W can be scanned with the near-infrared laser light in the second direction.

As described above, the laser beam scanning unit 4 receives not only near-infrared laser beams, but also guide light that has passed through the dichroic mirror 35a of the downstream merging mechanism 35, or range-finding light that has been reflected by the same mirror 35a. will also enter. By operating the first scanner 41 and the second scanner 42 respectively, the laser beam scanning unit 4 according to the present embodiment can two-dimensionally scan the incident guide light or distance measuring light.

In addition, the rotational postures that the first mirror 41a and the second mirror 42a can take are basically such that when the near-infrared laser light is reflected by the second mirror 42a, the reflected light passes through the transmission window 19. (see also FIGS. 7 and 8).

(Transparent window 19)
FIG. 9 is a diagram illustrating the configuration of the transparent window 19. As shown in FIG. As shown in the figure, the transmissive window 19 is composed of two windows. The transmission window 19 according to the present embodiment is provided in the housing 10 and configured to transmit the near-infrared laser light, the guide light, and the range-finding light two-dimensionally scanned by the laser light scanning unit 4. ing.

Specifically, the transmission window 19 has a first window 19 a arranged outside the housing 10 and a second window 19 b arranged inside the housing 10 . Of these windows, the second window 19b is fixed to the bottom plate 10a of the housing 10 and transmits the near-infrared laser beam or the like reflected by the second mirror 42a.

On the other hand, the first window 19a is detachably attached to the bottom plate 10a of the housing 10, and allows the near-infrared laser beam or the like that has passed through the second window 19b to pass therethrough again.

Using the first window 19a and the second window 19b in combination is advantageous in sealing the inside of the housing 10 . In addition, since the first window 19a is more likely to come into contact with the outside air than the second window 19b, the maintenance of the marker head 1 and the laser processing apparatus L can be improved by making the window detachable.

The transmissive window 19 is arranged at a reference position where the optical path length between the distance measuring light emitting portion 5A and the distance measuring light emitting portion 5A is known. Especially in this embodiment, the optical path length of the optical path connecting the first window 19a and the distance measuring light source 51 is known.

(Range measurement unit 5)
As shown in FIG. 3B, the distance measurement unit 5 projects distance measurement light through the laser beam scanning section 4 and irradiates the surface of the work W with the light. The distance measurement unit 5 also receives the distance measurement light reflected by the surface of the work W via the laser beam scanning section 4 .

The distance measuring unit 5 is mainly divided into a module for projecting distance measuring light and a module for receiving distance measuring light. Specifically, the distance measuring unit 5 is provided inside the housing 10 and emits distance measuring light for measuring the distance from the marker head 1 in the laser processing apparatus L to the surface of the work W. and the distance measuring light emitted from the distance measuring light emitting unit 5A provided inside the housing 10 and reflected by the workpiece W is sent through the laser beam scanning unit 4. and a distance measuring light receiving portion 5B that receives the light. The distance measuring unit 5 further includes a support base 50 that supports the distance measuring light emitting portion 5A and the distance measuring light receiving portion 5B from below. ing.

As described above, the distance measuring unit 5 is provided in the space on the other side in the short direction of the first space S1. As shown in FIG. 7, the distance measuring unit 5 emits distance measuring light forward along the longitudinal direction of the housing 10 and receives distance measuring light propagating substantially backward along the longitudinal direction.

Further, the distance measuring unit 5 is optically coupled to the laser light guide section 3 via the dichroic mirror 35a. As described above, the distance measuring unit 5 projects distance measuring light along the longitudinal direction of the housing 10 . On the other hand, the dichroic mirror 35a reflects the range-finding light that propagates along the lateral direction of the housing 10 rather than along its longitudinal direction.

Therefore, a bend mirror 59 is provided inside the housing 10 to form an optical path connecting the distance measuring unit 5 and the dichroic mirror 35a (see FIGS. 6 and 7).

Therefore, the distance measuring light incident on the bend mirror 59 from the distance measuring light emitting portion 5A is reflected by the same mirror 59 and enters the dichroic mirror 35a. On the other hand, the distance measuring light returned to the laser beam scanning unit 4 and reflected by the dichroic mirror 35a is incident on the bend mirror 59 and is reflected by the same mirror 59 to enter the distance measuring light receiving unit 5B.

The configuration of each part forming the distance measuring unit 5 will be described in order below.

-Ranging light output unit 5A-
The distance measuring light emitting unit 5A is provided inside the housing 10 and is configured to emit distance measuring light for measuring the distance from the marker head 1 in the laser processing apparatus L to the surface of the work W. ing.

Specifically, the distance measuring light emitting unit 5A includes the above-described distance measuring light source 51 and the projection lens 52, a casing 53 that accommodates these, and a pair of It has guide plates 54L and 54R. The distance measuring light source 51 , the projection lens 52 , and the guide plates 54 L and 54 R are arranged in order from the rear side of the housing 10 , and their arrangement direction is substantially the same as the longitudinal direction of the housing 10 .

The casing 53 is formed in a tubular shape extending along the longitudinal direction of the housing 10 and the support base 50 , and one side in the same direction, that is, one end corresponding to the rear side of the housing 10 is provided with a distance measuring light source 51 . is attached, while a projection lens 52 is attached to the other end corresponding to the front side of the housing 10 . The space between the distance measuring light source 51 and the projection lens 52 is substantially airtightly closed.

The distance measuring light source 51 emits distance measuring light toward the front side of the housing 10 according to the control signal input from the control unit 101 . Specifically, the distance measuring light source 51 can emit laser light in the visible light range as the distance measuring light. In particular, the distance measuring light source 51 according to this embodiment emits a red laser beam having a wavelength of around 690 nm as distance measuring light.

The distance measuring light source 51 is also fixed in such a posture that the optical axis Ao of the red laser light emitted as the distance measuring light is along the longitudinal direction of the casing 53 . Therefore, the optical axis Ao of the distance measuring light extends along the longitudinal direction of the housing 10 and the support base 50 , passes through the central portion of the projection lens 52 and reaches the outside of the casing 53 .

The projection lens 52 is positioned between the pair of light receiving elements 56L and 56R and the light receiving lens 57 in the distance measuring light receiving section 5B in the longitudinal direction of the support base 50 . The projection lens 52 is oriented so that the optical axis Ao of the distance measuring light passes through it.

The projection lens 52 can be, for example, a plano-convex lens, and can be fixed with a spherical convex surface facing the outside of the casing 53 . The projection lens 52 collects the distance measuring light emitted from the distance measuring light source 51 and emits it to the outside of the casing 53 . The distance measuring light emitted outside the casing 53 reaches the guide plates 54L and 54R.

The guide plates 54L and 54R are configured as a pair of members aligned in the lateral direction of the support base 50, and each can be a plate-like body extending in the longitudinal direction of the support base 50. As shown in FIG. A space for emitting the distance measuring light is defined between one guide plate 54L and the other guide plate 54R. The distance measuring light emitted to the outside of the casing 53 passes through the space thus partitioned and is output.

Therefore, the distance measuring light emitted from the distance measuring light source 51 passes through the space inside the casing 53, the central portion of the projection lens 52, the space between the guide plates 54L and 54R, and reaches the outside of the distance measuring unit 5. output. The output distance measuring light is reflected by the bend mirror 59 and the dichroic mirror 35 a in the downstream merging mechanism 35 and enters the laser beam scanning section 4 .

The distance measuring light incident on the laser beam scanning unit 4 is sequentially reflected by the first mirror 41a of the first scanner 41 and the second mirror 42a of the second scanner 42, and passes through the transmission window 19 to the outside of the marker head 1. will be emitted to

As described in the description of the laser beam scanning unit 4, the surface of the workpiece W can be scanned with the distance measuring light in the first direction by adjusting the rotational posture of the first mirror 41a of the first scanner 41. FIG. At the same time, the motor of the second scanner 42 is actuated to adjust the rotational attitude of the second mirror 42a, so that the surface of the workpiece W can be scanned with the distance measuring light in the second direction.

The distance measuring light thus scanned is reflected on the surface of the work W. As shown in FIG. A portion of the reflected distance measuring light (hereinafter also referred to as “reflected light”) enters the inside of the marker head 1 through the transmission window 19 . The reflected light that has entered the inside of the marker head 1 returns to the laser light guide section 3 via the laser light scanning section 4 . Since the reflected light has the same wavelength as the distance measuring light, it is reflected by the dichroic mirror 35 a of the downstream merging mechanism 35 in the laser beam guide section 3 and enters the distance measuring unit 5 via the bend mirror 59 .

-Ranging light receiving part 5B-
The distance measuring light receiving section 5B is provided inside the housing 10, and receives the distance measuring light emitted from the distance measuring light emitting section 5A and reflected by the workpiece W (equivalent to the aforementioned "reflected light"). is configured to

Specifically, the distance measuring light receiving section 5B has a pair of light receiving elements 56L and 56R and a light receiving lens 57. As shown in FIG. A pair of light-receiving elements 56L and 56R are arranged at the rear end of the support base 50, respectively, while the light-receiving lenses 57 are arranged at the front end of the support base 50, respectively. Therefore, the pair of light receiving elements 56L and 56R and the light receiving lens 57 are arranged substantially along the longitudinal direction of the housing 10 and the support base 50. As shown in FIG.

The pair of light-receiving elements 56L and 56R are arranged inside the housing 10 so as to sandwich the optical axis Ao of the distance measuring light from the distance measuring light emitting section 5A. A pair of light receiving elements 56L and 56R receive the reflected light that has returned to the laser beam scanning section 4, respectively.

Specifically, the pair of light receiving elements 56L and 56R are arranged in a direction orthogonal to the optical axis Ao of the distance measuring light emitting section 5A. In this embodiment, the direction in which the pair of light receiving elements 56L and 56R are arranged is the same as the lateral direction of the housing 10 and the support base 50, that is, the horizontal direction. In the same direction, one light receiving element 56L is arranged on the left side of the distance measuring light source 51, and the other light receiving element 56R is arranged on the right side of the distance measuring light source 51. As shown in FIG.

The pair of light-receiving elements 56L and 56R each have a light-receiving surface directed obliquely forward, detects the light-receiving position of the reflected light on each light-receiving surface, and outputs a signal (detection signal) indicating the detection result. to output Detection signals output from the light receiving elements 56L and 56R are input to the marker controller 100 and reach the distance measurement section 103 via the dirt detection section 104. FIG.

Elements that can be used as the light receiving elements 56L and 56R include, for example, a CMOS image sensor composed of complementary MOS (CMOS), a CCD image sensor composed of a charge-coupled device (CCD), and an optical position sensor. A sensor (Position Sensitive Detector: PSD) and the like are included.

In this embodiment, each of the light receiving elements 56L and 56R is constructed using a CMOS image sensor. In this case, each of the light receiving elements 56L and 56R can detect not only the light receiving position of the reflected light but also the light receiving amount distribution (light receiving waveform). That is, when each of the light receiving elements 56L and 56R is configured using a CMOS image sensor, pixels are arranged at least in the horizontal direction on each light receiving surface a. In this case, each of the light receiving elements 56L and 56R can read out a signal for each pixel, amplify it, and output it to the outside. The intensity of the signal in each pixel is determined based on the intensity of the reflected light at the spot when the reflected light forms a spot on the light receiving surface 56a.

Note that when each light receiving element 56L, 56R is configured using an element capable of detecting the light receiving amount distribution (light receiving waveform) like a CMOS image sensor, the magnitude of the light receiving amount in each light receiving element 56L, 56R can be measured. The intensity of the distance light, that is, the intensity of the distance measurement light emitted from the distance measurement light emitting portion 5A (hereinafter also referred to as "projection light amount"), and the gain for amplifying the signal for each pixel (hereinafter referred to as (also referred to as "light receiving gain"). In addition to the gain, it can be adjusted using the exposure time in each of the light receiving elements 56L and 56R.

The pair of light receiving elements 56L and 56R according to the present embodiment can detect at least the peak position indicating the light receiving position of the reflected light and the amount of received light of the reflected light. As an index indicating the amount of received light, for example, the height of the peak in the distribution of the amount of reflected light can be used. Alternatively, the total value, average value, or integral value of the received light amount distribution may be used.

Although the present embodiment uses the peak position of the distribution of the amount of received light as an index indicating the position of receiving the reflected light, it may instead be the position of the center of gravity of the distribution of the amount of received light.

The light-receiving lens 57 is arranged inside the housing 10 so that the optical axes of the pair of light-receiving elements 56L and 56R pass through. The light-receiving lens 57 is also provided in the middle of the optical path connecting the downstream-side junction mechanism 35 and the pair of light-receiving elements 56L and 56R, and receives the reflected light that has passed through the downstream-side junction mechanism 35 into the pair of light-receiving elements 56L and 56R. Light can be collected on each light receiving surface.

The light-receiving lens 57 collects the reflected light that has returned to the laser beam scanning unit 4 and forms spots of the reflected light on the light-receiving surfaces of the light-receiving elements 56L and 56R. Each of the light receiving elements 56L and 56R outputs to the distance measuring section 103 a signal indicating the peak position of the spot thus formed and the amount of received light.

The laser processing apparatus L basically measures the distance to the surface of the workpiece W based on the light receiving position of the reflected light on the light receiving surface of each of the light receiving elements 56L and 56R (in this embodiment, the position of the peak of the spot). can do. A so-called triangulation method is used as a distance measurement method.

<About distance measurement method>
FIG. 10 is a diagram for explaining the triangulation method. Although only the distance measuring unit 5 is illustrated in FIG. 10, the following description is also applicable to the case where the distance measuring light is emitted via the laser beam scanning section 4 as described above.

As illustrated in FIG. 10, when the distance measuring light is emitted from the distance measuring light source 51 in the distance measuring light emitting portion 5A, the surface of the workpiece W is irradiated with the distance measuring light. When the distance measuring light is reflected by the work W, the reflected light (particularly diffusely reflected light) propagates substantially isotropically if the influence of specular reflection is eliminated.

Although the reflected light thus propagated includes a component incident on the light receiving element 56L via the light receiving lens 57, the angle of incidence on the light receiving element 56L increases or decreases according to the distance between the marker head 1 and the workpiece W. will do. When the angle of incidence on the light receiving element 56L increases or decreases, the light receiving position on the light receiving surface 56a increases or decreases.

Thus, the distance between the marker head 1 and the workpiece W and the light receiving position on the light receiving surface 56a are associated with a predetermined relationship. Therefore, by grasping the relationship in advance and storing it in the marker controller 100, for example, the distance between the marker head 1 and the workpiece W can be calculated from the light-receiving position on the light-receiving surface 56a. Such a calculation method is nothing but a technique using a so-called triangulation method.

That is, the distance measuring unit 103 described above measures the distance from the laser processing apparatus L to the surface of the work W by the triangulation method based on the light receiving position of the distance measuring light in the distance measuring light receiving unit 5B.

Specifically, the relationship between the light-receiving position on the light-receiving surface 56a and the distance between the marker head 1 and the surface of the workpiece W is stored in advance in the condition setting storage unit 102 described above. On the other hand, the distance measuring section 103 receives a signal indicating the light receiving position of the distance measuring light in the distance measuring light receiving section 5B, more specifically, the peak position of the spot formed by the reflected light on the light receiving surface 56a.

The distance measurement unit 103 measures the distance to the surface of the workpiece W based on the signal thus input and the relationship stored in the condition setting storage unit 102 . The measured values thus obtained are input to, for example, the control unit 101 and used by the control unit 101 to control the Z scanner 33 and the like.

<Regarding the processing procedure of the workpiece W>
As an example of using the measurement result of the distance measuring unit 103, the processing procedure of the workpiece W by the laser processing device L will be described below. FIG. 11 is a flow chart illustrating the procedure for machining the workpiece W. As shown in FIG.

The control process illustrated in FIG. 11 is executed by the control unit 101 capable of controlling the excitation light generation unit 110, the laser light output unit 2, the Z scanner 33, the laser light scanning unit 4, the distance measurement light emission unit 5A, and the guide light source 36. It is possible.

First, in step S<b>101 , the processing conditions for laser processing are set by the user operating the operation terminal 800 . The processing conditions set in step S101 include, for example, the contents (marking pattern) such as character strings printed on the surface of the workpiece W, and the layout of such character strings.

In subsequent step S102, the control unit 101 selects a portion of the surface of the work W where the distance from the marker head 1 is to be measured (hereinafter also referred to as a "measurement point") based on the processing conditions set in step S101. is determined at multiple points.

In subsequent step S103, the control unit 101 measures the distance from the laser processing apparatus L to the surface of the work W via the distance measuring unit 103 by controlling the distance measuring light emitting unit 5A.

Specifically, in step S103, the control unit 101 emits the distance measuring light from the distance measuring light emitting unit 5A to each measurement point determined in step S102, and the reflected light is sent to the distance measuring light receiving unit 5B. light is received by A signal indicating the light receiving position of the reflected light in the distance measuring light receiving section 5B is input to the distance measuring section 103, and the distance measuring section 103 measures the distance to the surface of the work W. FIG. Distance measurement section 103 inputs a signal indicating the distance thus measured to control section 101 .

In subsequent step S104, the control unit 101 determines the control parameters of the Z scanner 33 based on the measurement results in step S103, ie, the distance measurement values at each measurement location, so that the focal position matches the measurement values.

Specifically, in step S104, the control unit 101 determines control parameters for the Z scanner 33 at each measurement point.

In subsequent step S105, the control unit 101 adjusts the focal position at each measurement location via the Z scanner 33, and after adjusting the focal position with the Z scanner 33, guides the work W to the surface of the work W via the guide light source 36. irradiate with light. At the same time, the control unit 101 traces the marking pattern with the guide light emitted from the guide light source 36 by controlling the laser beam scanning unit 4 .

Since the upstream merging mechanism 31 for merging the guide light with the near-infrared laser light is provided on the upstream side of the Z scanner 33, by adjusting the focal position with the Z scanner 33, only the near-infrared laser light is used. It is possible to adjust the focal position of the guide light as well.

Further, the tracing of the marking pattern by the guide light is repeatedly performed by appropriately controlling the laser beam scanning section 4. FIG. As a result, the marking pattern is continuously displayed on the surface of the workpiece W due to the afterimage effect of the human eye. At this time, in order to make the continuous display by the afterimage effect effective, it is conceivable to set the scanning speed of the guide light to the minimum speed at which the afterimage phenomenon occurs or higher. On the other hand, depending on conditions such as the material of the work W and the output of the near-infrared laser light, the scanning speed of the near-infrared laser light may become excessively slow during printing. In response to this, the scanning speed of the guide light is set to a speed faster than the scanning speed of the near-infrared laser light, that is, a speed equal to or higher than the minimum speed at which the afterimage phenomenon occurs.

In subsequent step S106, the control unit 101 completes the setting related to the marking pattern, and executes print processing based on the setting. Instead of step S106, the settings related to the marking pattern may be transferred to the condition setting storage unit 102 or the operation terminal 800 and stored.

<Regarding dirt on transmission window 19>
12A and 12B are diagrams for explaining contamination of the transmission window 19. FIG. FIG. 13A is a diagram for explaining the reflection of distance measuring light by the transmission window 19, and FIG.

As shown in FIG. 12, when the laser processing apparatus L is operated for a long period of time, dirt adheres to the transmission window 19 (especially the first window 19a). As shown in the right diagram of FIG. 12, if the transmission window 19 becomes excessively dirty, it affects the measurement by the distance measuring unit 5, the processing performance by the near-infrared laser beam, and the processing quality of the workpiece W. may give

That is, when the transmission window 19 is not so dirty as shown in the left diagram of FIG. 12, the distance measuring light is reflected by the dirt adhering to the transmission window 19 as shown in the left diagram of FIG. 13A. You will be able to pass through this without In this case, assuming that the influence of specularly reflected light is ignored, the light receiving element 56L receives only the reflected light that is reflected by the surface of the workpiece W and forms a peak at the predetermined position X1, as shown in FIG. 13B(a). will detect.

However, if the transmission window 19 is excessively soiled as shown in the right diagram of FIG. 12, at least part of the range-finding light is lost due to the dirt adhering to the transmission window 19, as shown in the right diagram of FIG. 13A. It will be reflected. In this case, as shown in FIGS. 13B(b) and 13B(c), the light receiving element 56L detects reflected light that is reflected by the surface of the transmission window 19 and forms a peak at a predetermined position X2 (≠X1). . When the transmission window 19 is heavily soiled, the amount of reflected light received is greater than when the dirt is small.

In particular, as shown in FIGS. 13B(b) and 13B(c), depending on the state of dirt on the transmission window 19, the light-receiving element 56L may detect the range-finding light reflected by the surface of the work W and the light reflected by the transmission window 19. There is a possibility of detecting both the ranging light and the

In contrast, the marker controller 100 according to the present embodiment can detect dirt on the transmissive window 19 and execute processing in consideration of the detection result.

Specifically, the contamination detection unit 104 detects the contamination on the transmission window 19 by specifying the distance measurement light caused by the light reflected by the transmission window 19 among the distance measurement light received by the distance measurement light receiving unit 5B. detect. An output unit 105 electrically connected to the contamination detection unit 104 outputs the result of detection by the contamination detection unit 104 .

As described above, the transmission window 19 is arranged at the reference position where the optical path length between the distance measuring light emitting section 5A and the distance measuring light emitting section 5A is known. Since the optical path length is known, the position of the peak of the ranging light reflected by the surface of the transmission window 19 can be presumed.

Therefore, the contamination detection unit 104 can detect contamination on the transmissive window 19 based on the light reception status at the light receiving position corresponding to the above-described reference position among the light receiving positions of the distance measuring light in the distance measuring light receiving unit 5B. can.

For example, if the peak position of the reflected light on the light-receiving surface 56a falls within a predetermined range, the dirt detection unit 104 can determine that the reflected light is caused by dirt on the transmissive window 19. can. The predetermined range used for this determination may be a numerical range including the light receiving position corresponding to the reference position.

Hereinafter, the light receiving position corresponding to the reference position will be referred to as "reference light receiving position". For convenience of explanation, it is assumed that the reference light receiving position is equal to the predetermined position X2 shown in FIG. 13B. In this case, the aforementioned predetermined range can be X2-ΔX<X2<X2+ΔX using the reference light receiving position X2.

In this manner, the dirt detection unit 104 can identify the reflected light reflected by the transmission window 19 based on the light receiving position of the reflected light. In addition to this, the dirt detection unit 104 can also determine the degree of dirt on the transmission window 19 based on the received amount of the reflected light.

Specifically, the dirt detection unit 104 can determine the degree of dirt on the transmission window 19 based on the amount of light received at the reference light receiving position X2. Specifically, the contamination detection unit 104 compares the amount of light received at the reference light receiving position X2 with a preset threshold value T, and if the amount of light received exceeds the threshold value T, the transmission window 19 is dirty. (see FIG. 13B(c)).

When carrying out such a determination, as an index indicating the amount of received light at the reference light receiving position X2, the height of the peak of the distribution of the amount of received light (waveform of received light) may be used. , an integral value, or the like may be used. When using the total value, average value, integral value, or the like of the received light amount distribution, a predetermined range including the reference light receiving position X2 is masked in order to suppress the influence of reflected light from the workpiece W, and You may exclude the influence of the reflected light received in .

Further, the threshold value T used in the determination may be stored in advance in the condition setting storage unit 102 in the marker controller 100 and/or in the storage device 803 in the operation terminal 800. Alternatively, the user may be allowed to set each time.

In the description below, the process of determining the presence and degree of dirt on the transmissive window 19 will be referred to as "window monitor". The marker controller 100 can execute a control process related to the window monitor in addition to the control process shown in FIG.

Here, the timing at which the marker controller 100 executes the window monitor may be when the laser processing system S, the laser processing apparatus L, the marker head 1, etc. are activated, or before or after executing the control process illustrated in FIG. Alternatively, the timing may be designated by the user via the operation unit 802 .

When the stain detection unit 104 executes the window monitor, the output unit 105 outputs the result of detection by the window monitor. The output destination of the output unit 105 may be the operation terminal 800, the external device 900, or other elements constituting the laser processing apparatus L. FIG. The number of output destinations by the output unit 105 is not limited to one, and may be plural.

For example, when the output destination of the output unit 105 is the operation terminal 800 , the detection result of the dirt detection unit 104 can be displayed on the display unit 801 or stored in the storage device 803 . Thereby, for example, the user can be prompted to replace or clean the transmission window 19 .

Also, when the output destination of the output unit 105 is the external device 900 , the detection result of the contamination detection unit 104 can be input to the PLC 902 . In this case, the PLC 902 can perform processing corresponding to dirt on the transparent window 19 .

Further, when the output destination of the output unit 105 is another element constituting the laser processing apparatus L, the detection result of the dirt detection unit 104 can be input to the distance measurement unit 103 . In this case, the distance measurement unit 103 may eliminate the received light amount distribution caused by the reflected light from the transmission window 19 . According to this, when the distance to the surface of the work W is measured, the influence of dirt on the transmission window 19 can be suppressed, and the distance measurement accuracy can be ensured.

As described above, the dirt detector 104 can determine the degree of dirt on the transmissive window 19 . The output unit 105 is connected to the history storage unit 106 in order to utilize the detection result. The output unit 105 inputs the detection result by the contamination detection unit 104 to the history storage unit 106 .

The history storage unit 106 can store temporal transition of detection results by the contamination detection unit 104 . The history storage unit 106 according to this embodiment can store the time transition of the amount of received light at the reference light receiving position X2. The contents stored in the history storage unit 106 can be communicated to the user via the display unit 801 or the like.

By the way, it is considered that the transmission window 19 will gradually become dirty as it is used for a long period of time. When the marker controller 100 according to the present embodiment is used, the amount of light received at the reference light receiving position X2, which was below the threshold T immediately after operation, will exceed the threshold T due to changes over time.

Therefore, the marker controller 100 can notify the user of a warning when the amount of received light stored in the history storage unit 106 (the amount of received light at the reference position X2) exceeds the threshold value T. FIG. This notification may be displayed on the display unit 801, or may be generated by ringing a buzzer.

Note that in the example shown in FIG. 2, the history storage unit 106 is configured as part of the marker controller 100, but the configuration is not limited to this. For example, the history storage unit 106 may be a component of the operation terminal 800 or may be separately provided as an external device 900 .

Note that the contamination detection unit 104 may perform window monitoring on a specific portion of the transmissive window 19, or may perform window monitoring on each area when the entire transmissive window 19 is divided into a plurality of areas. good too.

In the case of the former configuration, the contamination detection unit 104 may perform window monitoring only for a portion of the transmissive window 19 through which the range-finding light and the near-infrared laser light are transmitted during printing. . Instead of this, the user may be allowed to specify each time the part where the window monitor is to be performed.

The latter configuration is adopted in this embodiment. In this case, the history storage unit 106 may store the amount of received light for each area, or may store the average value of the amount of received light for the entire area. Also, when window monitoring is performed for each area, the amount of projected light and/or the received light gain may be varied for each area.

In general, the intensity of the reflected light is higher at a portion closer to the second mirror 42a. Further, as shown in FIG. 9, the second mirror 42a is arranged directly above the substantially central portion of the transmission window 19. As shown in FIG. In other words, the intensity of the reflected light tends to be higher at the central portion of the transmission window 19 than at its peripheral portion. In view of this tendency, the area corresponding to the central portion of the transmissive window 19 and the area corresponding to its peripheral portion are set so that the intensity of the reflected light due to dirt on the window 19 is uniform. may This setting can be implemented by varying the amount of projected light and/or the received light gain for each area.

When window monitoring is performed for each area, window monitoring may be performed multiple times for each area. It is also possible to average the received light waveforms obtained by each window monitor and detect dirt on the transmission window 19 based on the average value.

In addition, when a plurality of laser processing devices L are set, the detection results of each laser processing device L are aggregated, and problems depending on the operating environment of the laser processing device L (for example, the amount of dust in the air) , and problems related to the setting position of the laser processing apparatus L).

The marker controller 100 according to this embodiment is configured to read prior information related to the window monitor before or after the window monitor is implemented. The advance information is stored in advance in the storage device 803, the condition setting storage unit 102, and the like. The prior information includes initial information of the transmissive window 19, light receiving element information related to the pair of light receiving elements 56L and 56R, window monitor date and time information, window monitor history information, and linking data.

Here, the initial information of the transmission window 19 includes the amount of received light, the amount of projected light, the gain of received light, etc. at the reference light receiving position X2 when the laser processing apparatus L is manufactured or when the transmission window 19 is cleaned or replaced. be These pieces of information are set for each area when the entire transparent window 19 is divided into a plurality of areas.

Further, the light receiving element information includes information indicating which of the pair of light receiving elements 56L and 56R is used for each area. In other words, the reflected light from the transmission window 19 includes the specular reflection in addition to the dirt. Since the layouts of the pair of light receiving elements 56L and 56R are different from each other, even if specularly reflected light is incident on one of the light receiving elements 56L, the specularly reflected light is not necessarily incident on the other light receiving element 56R. Further, the light receiving elements 56L and 56R into which specularly reflected light can be incident are different for each area. Therefore, as the light receiving element information, the light receiving elements 56L and 56R that are considered not to receive specularly reflected light are set for each area.

The light receiving element information also includes information indicating the reference light receiving position X2. By using this information, it becomes possible to mask the predetermined range including the reference light receiving position X2 and exclude the influence of the reflected light received outside the predetermined range.

The window monitor date information includes the date and time when the window monitor was performed. This information is mainly stored by the history storage unit 106. FIG.

The history information of the window monitor includes the amount of light received at the reference light receiving position X2 obtained for each area and the average value for all areas.

The linking data can include data linking the amount of light received at the reference light receiving position X2 obtained by the window monitor and whether or not printing was actually possible. Using this data is advantageous in determining the threshold value T to be compared with the amount of received light.

(Specific example of window monitor)
A specific example of the window monitor will be described below. FIG. 14 is a flowchart illustrating processing related to dirt determination of the transmissive window 19 .

First, in step S201 of FIG. 14, the marker controller 100 determines whether or not it is time to perform the window monitor. This timing may be, as described above, when the laser processing system S, the laser processing apparatus L, the marker head 1, etc. are activated, or before or after executing the control process illustrated in FIG. The timing may be specified by the user via 802 . If it is determined that it is time to execute the window monitor (step S201: YES), the process proceeds to step S202, and if it is determined that it is not time to execute the window monitor (step S201: NO), step S201 is repeated.

In subsequent step S202, the contamination detection unit 104 reads information required for implementation of the window monitor among the advance information related to the window monitor. The information read in step S202 includes, for example, light-receiving element information and a threshold value T with which the amount of received light is compared.

In the subsequent step S203, the marker controller 100 controls the laser beam scanning unit 4 to scan the area to be window monitored with distance measuring light.

In subsequent step S204, history storage unit 106 updates the stored content. Specifically, the history storage unit stores the newly obtained amount of received light for each area in chronological order.

In subsequent step S205, the contamination detection unit 104 compares the amount of received light newly stored in step S204 and/or its average value with the threshold value T read in step S202. If this determination is YES, the process proceeds to step S206, and if NO, step S206 is skipped and the process proceeds to step S207.

In step S206, the marker controller 100 notifies the user of a warning. This notification is displayed on the display unit 801 in the example shown in FIG.

In step S207, the history storage unit 204 displays the history of the received light amount on the display unit 801, and returns.

Note that the processing from step S205 to step S206 can be omitted as appropriate.

Further, the user can select whether or not to perform the display related to step S207. For example, the history of the amount of received light may be displayed each time the window monitor is performed, or the history of the amount of received light may be displayed each time the window monitor is performed a certain number of times.

Also, the display mode in step S207 can be changed as appropriate. For example, a numerical value of the amount of received light may be displayed, or a graph may be displayed. The stored contents updated in step S204 may be output periodically as a log file, or may be automatically output by e-mail.

15, 16, 17 and 18 illustrate display modes on the display unit 801. FIG. Specifically, FIG. 15 is a diagram illustrating a display mode of various types of information including dirt determination, and FIG. 16 is a diagram illustrating time transition of dirt determination. Further, FIG. 17 is a diagram illustrating a notification mode of dirt determination, and FIG. 18 is a diagram illustrating threshold setting of dirt determination.

First, as shown in FIG. 15, the display unit 801 can display the date of window monitoring and the results of the window monitoring as operation information of the laser processing apparatus L as a laser marker. By pressing the button B1 with a mouse or the like, the history of the amount of received light can be displayed as a graph, and by pressing the button B2, a log file summarizing the history of the amount of received light can be output.

Further, as shown in FIG. 16, the history of the amount of light received by the window monitor can be graphically displayed on the display unit 801 . In the graph shown in FIG. 16, the horizontal axis indicates the date of window monitoring, and the vertical axis indicates the amount of received light. In this graph, the history for the past one month is displayed, but the history display period can be changed by operating the button B3, for example. Also, in the graph shown in FIG. 16, a straight line T indicating a threshold value may be displayed.

Also, FIG. 17 exemplifies the warning displayed in step S206 of FIG. For example, by pressing the button B4, the warning history can be checked.

Also, FIG. 18 exemplifies a setting screen for the threshold value T to be compared with the amount of received light. As shown in this setting screen, the threshold value T may be manually changed by operating the input box B5, and whether or not to issue a warning may be manually switched by operating the check box B6. may Alternatively, the window monitor can be manually started by pressing the button B7 labeled "measurement", for example.

As described above, when the transmission window 19 is dirty, the distance measuring light receiving section 5B receives the distance measuring light reflected by the surface of the workpiece W instead of the distance measuring light reflected by the surface of the work W, or In addition to this distance measuring light, the distance measuring light reflected by the transmissive window 19 is also received.

Here, the distance to the surface of the work W varies depending on the type of the work W and the like. On the other hand, the distance to the transparent window 19 does not change regardless of the type of workpiece W. Therefore, the light receiving position caused by the contamination of the transmission window 19 can be estimated in advance.

Therefore, for example, by considering the location of each light receiving position, the dirt detection unit 104 can detect the distance measuring light caused by the light reflected by the transmission window 19 from the distance measuring light received by the distance measuring light receiving unit 5B. can be specified. This allows the dirt detection unit 104 to detect dirt on the transmission window 19 .

A detection result by the contamination detection unit 104 is output by the output unit 105 . As a result, as shown in FIG. 14, it is possible to prompt the user to replace the transmissive window 19, or to execute processing considering the presence or absence of contamination. This makes it possible to suppress deterioration in measurement accuracy and processing performance due to contamination of the transmission window 19 .

1 marker head 10 housing 19 transmission window 19a first window 19b second window 2 laser light output section 4 laser light scanning section 5 distance measurement unit 5A distance measurement light emission section 5B distance measurement light reception section 56L light receiving element 56R light receiving element 100 Marker controller 101 Control unit 103 Distance measurement unit 104 Dirt detection unit 105 Output unit 106 History storage unit 110 Excitation light generation unit L Laser processing device S Laser processing system T Threshold value W Work (workpiece)
X2 Reference light receiving position (light receiving position corresponding to the reference position)

Claims (5)

an excitation light generator that generates excitation light;
a laser light output unit that generates laser light based on the excitation light generated by the excitation light generation unit and that emits the laser light;
a laser beam scanning unit that irradiates a workpiece with the laser beam emitted from the laser beam output unit and performs two-dimensional scanning on the surface of the workpiece;
a housing in which at least the laser light output unit and the laser light scanning unit are provided;
A laser processing apparatus comprising a transmission window provided in the housing and through which the laser beam two-dimensionally scanned by the laser beam scanning unit is transmitted,
a distance measuring light emitting unit provided inside the housing for emitting distance measuring light for measuring a distance from the laser processing device to the surface of the workpiece toward the laser beam scanning unit;
a distance measuring light receiving unit provided inside the housing for receiving, via the laser beam scanning unit, distance measuring light emitted from the distance measuring light emitting unit and reflected by the workpiece;
a distance measuring unit that measures the distance from the laser processing device to the surface of the workpiece by a triangulation method based on the light receiving position of the distance measuring light in the distance measuring light receiving unit;
a contamination detection unit that detects contamination on the transmissive window by specifying ranging light caused by reflected light from the transmissive window among the ranging light received by the ranging light receiving unit;
and an output unit for outputting a result of detection by the contamination detection unit. In the laser processing apparatus according to claim 1,
The transmission window is arranged at a reference position where the optical path length between the distance measuring light emitting unit and the distance measuring light emitting unit is known,
The contamination detection unit detects contamination on the transmissive window based on a light receiving state at a light receiving position corresponding to the reference position among distance measuring light receiving positions in the distance measuring light receiving unit. Laser processing equipment. In the laser processing apparatus according to claim 2,
The distance measuring light receiving unit is configured to be able to detect the amount of received light,
The laser processing apparatus, wherein the contamination detection unit detects the degree of contamination on the transmission window based on the amount of light received at the light receiving position corresponding to the reference position. In the laser processing apparatus according to claim 3,
The contamination detection section compares the amount of light received at the light receiving position corresponding to the reference position with a preset threshold value, and if the amount of received light exceeds the threshold value, the transmission window is contaminated. A laser processing device characterized by determining that the In the laser processing apparatus according to any one of claims 1 to 4,
A laser processing apparatus, comprising: a history storage unit connected to the output unit and storing a time transition of detection results of the dirt detection unit.

Images