JP2021104522A - Laser processing device - Google Patents

Abstract

To secure the measurement accuracy of a distance while coaxializing guide light and range-finding light to laser beams for processing.SOLUTION: A laser processing device L includes: a laser beam output part 2 for outputting near-infrared laser beams; a laser beam scan part 4 for scanning the near-infrared laser beams; a guide light source 36 for outputting guide light; an upstream confluence mechanism 31 for joining the guide light with a laser optical path P from the laser beam output part 2 to the laser beam scan part 4; a range-finding light outputting part 5A for outputting range-finding light; a downstream confluence mechanism 35 disposed between the upstream confluence mechanism 31 and the laser beam scan part 4 in the laser optical path P, and joining the range-finding light with the laser optical path P; and a range-finding light receiving part 5B for receiving the range-finding light reflected by a workpiece W and returning via the downstream confluence mechanism 35. The downstream confluence mechanism 35 has an optical member 35a for selectively reflecting or transmitting only a wavelength band of the range-finding light among wavelength bands of the near-infrared laser beams, the guide light and the range-finding light.SELECTED DRAWING: Figure 13B

Description

The technique disclosed herein relates to a laser processing apparatus such as a laser marking apparatus that performs processing by irradiating a work piece with a laser beam.

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

For example, Patent Document 1 describes an objective condensing lens that condenses laser light (pulse laser light) emitted from a laser light source, and between the objective condensing lens and an object to be processed (processed object). A laser processing apparatus including a distance measuring sensor for measuring a distance and an actuator for adjusting a focal position of a laser beam based on the measurement result by the distance measuring sensor is disclosed.

The distance measuring sensor according to Patent Document 1 is supported by a Z-axis stage as shown in the same document. Therefore, this distance measuring sensor has a non-variable distance measuring position and measures the distance to a fixed point.

It is also widely known that a laser machining apparatus projects a machining pattern on the surface of a work piece by emitting a guide light on the surface of the work piece so that the user can visually recognize the machining content in advance. There is.

For example, the laser processing apparatus disclosed in Patent Document 2 is configured to include a guide light emitting unit (guide light source) capable of emitting guide light. This guide light emitting unit is coaxial with the optical axis of the laser light scanning system, and the guide light can be scanned by the laser light scanning system.

Japanese Unexamined Patent Publication No. 2006-315301 Japanese Unexamined Patent Publication No. 2008-227377

In the configuration in which the distance measuring position is non-variable as in Patent Document 1, there is room for improvement in the usability of the distance measuring sensor. Therefore, by making the optical axis of the distance measuring light emitted from the distance measuring sensor and the optical axis of the laser light for processing (particularly, the optical axis of the laser light scanning system) coaxial, the laser light scanning system is used. It is conceivable to scan the distance measurement light.

However, in a device provided with a coaxialized guide light emitting unit such as the laser processing device disclosed in Patent Document 2, if the distance measuring sensor is also coaxialized, the surface of the workpiece is covered. At least a part of the reflected distance measuring light may return to the guide light emitting portion instead of the distance measuring sensor, and the amount of light received by the distance measuring sensor may decrease. A decrease in the amount of light received by the distance measuring sensor is inconvenient because it causes a decrease in measurement accuracy.

The technology disclosed here was made in view of this point, and the purpose is to ensure the accuracy of distance measurement while coaxializing the guide light and the distance measuring light with the laser light for processing. It is in.

Specifically, the first aspect of the present disclosure is to generate a laser beam based on an excitation light generation unit that generates an excitation light and an excitation light generated by the excitation light generation unit, and emit the laser light. A laser light output unit, a laser light scanning unit that irradiates a work piece with laser light emitted from the laser light output unit, and two-dimensionally scans the surface of the work piece, and at least the laser light output. The present invention relates to a laser processing apparatus including a unit and a housing provided with the laser light scanning unit inside. This laser processing device is provided inside the housing, and has a guide light emitting portion that emits guide light for projecting a predetermined processing pattern onto the surface of the workpiece, and the inside of the housing. A guide light merging mechanism provided in the middle of the laser light path from the laser light output section to the laser light scanning section and merging the guide light emitted from the guide light emitting section into the laser light path, and inside the housing. A distance measuring light emitting portion that is provided and emits distance measuring light for measuring the distance from the laser processing apparatus to the surface of the work piece, and the guide light confluence of the laser light path inside the housing. A distance measuring light merging mechanism provided between the mechanism and the laser light scanning unit and merging the distance measuring light emitted from the distance measuring light emitting unit into the laser light path, and a distance measuring light merging mechanism provided inside the housing. A distance measuring light receiving unit that receives the distance measuring light that is reflected on the surface of the workpiece and returns via the laser light scanning unit and the distance measuring light merging mechanism, and the distance measuring unit in the distance measuring light receiving unit. A distance measuring unit for measuring the distance from the laser processing apparatus to the surface of the workpiece based on the light receiving position is provided.

According to the first aspect of the present disclosure, the distance measuring light merging mechanism has an optical member that guides the distance measuring light reflected on the surface of the workpiece to the distance measuring light receiving portion. The optical member selectively reflects or transmits only the wavelength band of the ranging light among the wavelength bands of the laser light, the guide light, and the ranging light, thereby measuring the ranging light. Guide to the distance light receiver.

According to this configuration, when measuring the distance from the laser processing apparatus to the surface of the workpiece, the ranging light emitting unit emits the ranging light. The distance measuring light emitted from the distance measuring light emitting unit passes through the distance measuring light merging mechanism and the laser light scanning unit in order, and irradiates the workpiece. The distance measuring light irradiated to the work piece is reflected by the work piece, and then returns to the distance measuring light receiving part by returning in order from the laser light scanning unit and the distance measuring light merging mechanism. The distance measuring unit measures the distance to the surface of the workpiece based on the light receiving position of the distance measuring light in the distance measuring light receiving unit.

Further, when the surface of the workpiece is irradiated with the guide light, the guide light emitting portion emits the guide light. The guide light emitted from the guide light emitting unit passes through the guide light merging mechanism, the ranging light merging mechanism, and the laser light scanning unit in order, and irradiates the workpiece.

According to the above configuration, the guide light emitting unit and the distance measuring light emitting unit are coaxial with the laser light for processing, respectively, so that the guide light and the ranging light can be scanned by the laser light scanning unit. become.

Specifically, the guide light merging mechanism is arranged in the middle of the laser light path from the laser light output unit to the laser light scanning part, and the distance measuring light merging mechanism is a combination of the guide light merging mechanism and the laser light scanning part in the laser light path. It is placed in between. When arranged in this way, the distance measuring light reflected on the surface of the workpiece and returning to the laser processing apparatus reaches the distance measuring light merging mechanism before reaching the guide light merging mechanism.

Here, the optical member constituting the ranging light merging mechanism selectively reflects or transmits only the wavelength band of the ranging light among the wavelength bands of the laser light for processing, the guide light, and the ranging light. As a result, the distance measuring light is configured to be guided to the distance measuring light receiving unit. With such a configuration, it is possible to suppress the propagation of the ranging light (particularly, the reflected light of the ranging light) to the guide light emitting section and increase the amount of received light in the ranging light receiving section. This makes it possible to suppress a decrease in measurement accuracy.

Further, according to the second aspect of the present disclosure, the optical member may be coated so as to selectively reflect or transmit only the wavelength band of the ranging light.

According to this configuration, it is possible to construct an optical member suitable for selective reflection or transmission.

Further, according to the third aspect of the present disclosure, the optical member selectively reflects only the wavelength band of the ranging light, while transmitting the wavelength bands of the laser light and the guide light. May be good.

According to this configuration, it is advantageous in suppressing a decrease in measurement accuracy.

Further, according to the fourth aspect of the present disclosure, the front and back surfaces of the optical member include a laser light incident surface on which the laser light and the guide light are incident, the laser light incident from the laser light incident surface, and the laser light incident surface. A laser light emitting surface through which the guide light is transmitted through the optical member is provided, and the laser light emitting surface selectively reflects only the wavelength band of the distance measuring light, and the laser light incident surface. May be configured to transmit the wavelength band of the ranging light.

According to this configuration, the laser beam emitting surface of the optical member can reflect the ranging light and guide the ranging light to the laser beam scanning section or the ranging light receiving section. However, it is not technically easy to set the reflectance of the laser beam emitting surface to exactly 100%. Therefore, a part of the ranging light incident on the laser beam emitting surface passes through the laser beam emitting surface without being reflected by the laser beam emitting surface. The ranging light that has passed through the laser beam emitting surface passes through the inside of the optical member while being refracted, and reaches the laser beam incident surface.

If the distance measuring light that has reached the laser light incident surface is reflected by the laser light incident surface and returns to the distance measuring light receiving part, the distance measuring light receiving part has the laser light emitting surface and the laser light. Both the distance-finding light reflected by the incident surface and the incident surface will be returned. In this case, the light receiving position in the ranging light receiving unit may be blurred. This is not desirable because it causes a decrease in measurement accuracy. Such a problem becomes more remarkable when the reflectance on the laser beam emitting surface is low.

Therefore, as in the above configuration, the laser beam incident surface transmits the wavelength band of the ranging light without reflecting it. As a result, the distance measuring light that has passed through the laser light incident surface and reached the laser light incident surface is suppressed from being reflected by the laser light incident surface so that it is emitted to the outside from the laser light incident surface. Become. As a result, blurring of the light receiving position in the distance measuring light receiving unit can be suppressed, and deterioration of measurement accuracy can be suppressed.

Further, according to the fifth aspect of the present disclosure, the optical member selectively transmits only the wavelength band of the ranging light, while selectively reflecting the wavelength bands of the laser light and the guide light. You may do.

According to this configuration, it is advantageous in suppressing a decrease in measurement accuracy.

Further, according to the sixth aspect of the present disclosure, the laser processing apparatus includes a focus adjusting unit provided inside the housing and adjusting the focal position of the laser light emitted from the laser light output unit. The ranging light merging mechanism may be arranged between the focusing adjustment unit and the laser light scanning unit in the laser optical path.

According to this configuration, the distance measuring light merging mechanism is arranged between the focusing light adjusting unit and the laser light scanning unit, and the distance measuring light emitted from the distance measuring light emitting unit and the laser light passing through the focusing light adjusting unit are provided. To be coaxial. Therefore, since the distance measuring light is coaxialized in the optical path on the upstream side of the laser light scanning unit, the distance measuring light can be scanned by operating the laser light scanning unit.

At the same time, the ranging light is coaxialized in the optical path on the downstream side of the focusing adjustment unit. Therefore, it is possible to secure the measurement resolution by the distance measuring light without making the opening of the focusing adjustment portion excessively large.

Further, according to the above configuration, not only the ranging light emitted from the ranging light emitting section but also the ranging light reflected by the workpiece and received by the ranging light receiving section passes through the focusing adjusting section. do not. Therefore, the ranging light emitting section and the ranging light receiving section can be arranged close to each other, and it is possible to suppress the influence of distortion of the housing due to the temperature change. This is effective in ensuring the measurement accuracy by the distance measuring unit.

Further, according to the seventh aspect of the present disclosure, the guide light merging mechanism is arranged between the laser light output unit and the focus adjustment unit in the laser optical path.

According to this configuration, the guide light emitted from the guide light emitting unit passes through the guide light merging mechanism, the focusing adjustment unit, the distance measuring light merging mechanism, and the laser light scanning unit in order to be processed. The object is irradiated.

Here, the guide light merging mechanism is provided between the laser light output unit and the focus adjustment unit, and the guide light emitted from the guide light emitting unit, the laser light emitted from the laser light output unit, and the laser light emitted from the laser light output unit. To be coaxial. Therefore, since the guide light and the laser light merge in the optical path on the upstream side of the focus adjustment unit, the focal position of the guide light can be adjusted by operating the focus adjustment unit. This makes it possible to improve the visibility of the guide light.

Further, according to the eighth aspect of the present disclosure, the wavelength bands of the distance measuring light and the guide light are both set in the visible light region, and the wavelength of the laser light is the distance measuring light and the guide light. It may be longer than the wavelength of.

According to this configuration, the distance measuring light and the guide light can be visually recognized by the user.

Further, according to the ninth aspect of the present disclosure, the wavelength of the laser beam is set to 1064 nm, 532 nm or 355 nm, the wavelength band of the ranging light is set to 680 nm or more and 695 nm or less, and the guide light is used. The wavelength band may be set to 645 nm or more and 660 nm or less.

According to this configuration, only the wavelength band of the ranging light can be selectively reflected or transmitted.

As described above, according to the laser processing apparatus, it is possible to secure the measurement accuracy of the distance while coaxializing the guide light and the distance measuring light with the laser light for processing.

FIG. 1 is a diagram illustrating the overall configuration of a laser processing system. FIG. 2 is a block diagram illustrating a schematic configuration of a 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 a marker head. FIG. 4 is a perspective view illustrating the appearance of the marker head. FIG. 5 is a diagram illustrating the configuration of the laser beam scanning unit. FIG. 6 is a diagram illustrating the configurations of a laser beam guide unit, a laser beam scanning unit, and a distance measuring unit. FIG. 7 is a cross-sectional view illustrating an optical path connecting the laser beam guide unit, the laser beam scanning unit, and the distance measuring unit. FIG. 8 is a perspective view illustrating an optical path connecting the laser beam guide unit, the laser beam scanning unit, and the distance measuring unit. FIG. 9 is a diagram illustrating a triangular ranging method. FIG. 10 is a flowchart illustrating a machining procedure of the work. FIG. 11 is a perspective view illustrating the configuration of the downstream side merging mechanism when viewed from the rear. FIG. 12 is a perspective view illustrating the configuration of the downstream side merging mechanism when viewed from the front. FIG. 13A is a diagram illustrating the reflectance of the laser beam incident surface according to the first embodiment. FIG. 13B is a diagram illustrating the reflectance of the laser beam emitting surface according to the first embodiment. FIG. 14A is a diagram illustrating the optical paths of the near-infrared laser beam and the guide light in the downstream merging mechanism. FIG. 14B is a diagram illustrating an optical path of distance measuring light in the downstream merging mechanism. FIG. 15A is a diagram corresponding to FIG. 3A illustrating a marker head according to a second embodiment of the laser processing apparatus. FIG. 15B is a diagram corresponding to FIG. 3B illustrating a marker head according to a second embodiment of the laser processing apparatus. FIG. 16A is a diagram corresponding to FIG. 13A illustrating the reflectance of the laser beam incident surface according to the second embodiment. FIG. 16B is a diagram corresponding to FIG. 13B illustrating the reflectance of the laser beam emitting surface according to the second embodiment. FIG. 17A is a diagram corresponding to FIG. 14A illustrating the optical paths of the near-infrared laser beam and the guide light in the second embodiment. FIG. 17B is a diagram corresponding to FIG. 14B illustrating the optical path of the ranging light according to the second embodiment. FIG. 18 is a diagram illustrating a combination of wavelengths that can be taken by near-infrared laser light, guide light, and ranging light.

Hereinafter, embodiments of the present disclosure will be described with reference to the drawings. The following description is an example.

That is, although the laser marker as an example of the laser processing apparatus will be described in the present specification, the technique disclosed herein can be generally applied to the laser application equipment regardless of the names of the laser processing apparatus and the laser marker.

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

<< First Embodiment >>
First, the laser processing system S including the first embodiment of the laser processing apparatus L will be described. In the following description, the first embodiment is simply referred to as the present embodiment unless it is emphasized that the configuration is specific to the first embodiment.

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

Then, the laser processing apparatus L illustrated in FIGS. 1 and 2 irradiates the work W as a work piece with the laser light emitted from the marker head 1 and scans the work W three-dimensionally on the surface of the work W. It is processed by doing so. The "three-dimensional scanning" here means a two-dimensional operation of scanning the irradiation position of the laser beam on the surface of the work W (so-called "two-dimensional scanning") and adjusting the focal position of the laser beam. It refers to a concept that collectively refers to a combination of one-dimensional movement and.

In particular, the laser processing apparatus L according to the present embodiment can emit a laser beam having a wavelength in the vicinity of 1064 nm as a laser beam for processing the work W. This wavelength corresponds to the near infrared (Near-InfraRed: NIR) wavelength range. Therefore, in the following description, the laser beam for processing the work W may be referred to as "near-infrared laser beam" to distinguish it from other laser beams. Of course, laser light having another wavelength may be used for processing the work W.

Specifically, the wavelength of the laser beam used for processing the work W can be set to, for example, 532 nm or 355 nm as an option other than 1064 nm. The wavelength of 532 nm corresponds to the green visible light region, and the wavelength of 355 nm corresponds to the wavelength region of near-ultraviolet (NUV).

Further, the laser processing apparatus L according to the present embodiment measures the distance (height) to the work W via the distance measuring unit 5 built in the marker head 1, and uses the measurement result to obtain near red. The focal position of the external laser beam 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 separate bodies in this embodiment, are electrically connected via electrical wiring, and are optically connected via an optical fiber cable.

More generally, one of the marker head 1 and the marker controller 100 can be incorporated into the other and integrated. 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 a memory, and is connected to the marker controller 100. The operation terminal 800 functions as a terminal for setting various processing conditions such as print settings and showing information related to laser processing to the user. The 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 composed of, for example, a liquid crystal display or an organic EL panel. The display unit 801 displays the operating status and processing conditions of the laser processing apparatus L as information related to laser processing. On the other hand, the operation unit 802 is composed of, for example, a keyboard and / or a pointing device. Here, the pointing device includes a mouse and / or a joystick and the like. 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 in laser processing based on the operation input by the user. The processing conditions include, for example, a character string to be printed on the work W, the contents of figures such as a barcode and a QR code (registered trademark) (marking pattern), an output required for laser light (target output), and an output. , The scanning speed (scanning speed) of the laser beam on the work W is included.

Further, the processing conditions according to the present embodiment also include conditions and parameters related to the above-mentioned distance measuring unit 5 (hereinafter, these are also referred to as “distance measuring conditions”). Such distance measuring conditions include, for example, data associating a signal indicating a detection result by the distance measuring unit 5 with the distance to the surface of the work W.

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

The operation terminal 800 can be integrated by incorporating it into, for example, the marker controller 100. In this case, the name of the control unit or the like is used instead of the “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 needed. 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, for example, the type and position of the work W transported on the production line. As the image recognition device 901, for example, an image sensor can be used. The PLC902 is used to control the laser machining system S according to a predetermined sequence.

In addition to the above-mentioned devices and devices, the laser processing device L can also be connected to devices for performing operations and controls, computers for performing various other processes, storage devices, peripheral devices, and the like. The connection in this case may be, for example, a serial connection such as IEEE1394, RS-232, RS-422 and USB, or a parallel connection. Alternatively, electrical, magnetic, or optical connections may be employed via 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. Further, as a storage medium used for a storage device for exchanging data, storing various settings, and the like, for example, various memory cards, magnetic disks, magneto-optical disks, semiconductor memories, hard disks, and the like can be used.

Hereinafter, a description relating to the hardware configuration of each of the marker controller 100 and the marker head 1 and a configuration relating to the control of the marker head 1 by the marker controller 100 will be described in order.

<Marker controller 100>
As shown in FIG. 2, the marker controller 100 includes a condition setting storage unit 102 that stores the above-mentioned processing conditions, a control unit 101 that controls the marker head 1 based on the processing conditions stored in the condition setting storage unit 102, and laser excitation. It includes an excitation light generation unit 110 that generates light (excitation light).

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

Specifically, the condition setting storage unit 102 is configured by using a volatile memory, a non-volatile memory, a hard disk drive (HDD), a solid state drive (SSD), and the like, and processing conditions. Information indicating the above can be temporarily or continuously stored. 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 unit 102.

(Control unit 101)
Based on the processing conditions stored in the condition setting storage unit 102, the control unit 101 includes at least the excitation light generation unit 110 in the marker controller 100, the laser light output unit 2 in the marker head 1, and the laser light guide unit 3. By controlling the laser beam scanning unit 4, the distance measuring unit 5, and the wide area camera (non-coaxial camera) 6 described later, the work W is printed.

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

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

Further, when the work W is actually processed, the control unit 101 reads, for example, a processing pattern (marking pattern) stored in the condition setting storage unit 102, and laser light a control signal generated based on the processing pattern. It is output to the scanning unit 4 and two-dimensionally scanned the near-infrared laser light. The control unit 101 exemplifies the "scanning control unit" in the present embodiment in that it controls the two-dimensional scanning of the near-infrared laser beam.

(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. It is provided with an excitation light condensing unit 113. The excitation light source 111 and the excitation light condensing unit 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 heat can be efficiently dissipated from the excitation light source 111.

Hereinafter, each part of the excitation light generation part 110 will be described in order.

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

The excitation light source 111 is supplied with a drive current from the excitation light source drive unit 112, and oscillates a laser beam corresponding to the drive 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 linearly arranged can be used. When an LD array or LD bar is used as the excitation light source 111, the laser light oscillated from each element is output in a line shape and incident on the excitation light condensing unit 113.

The excitation light condensing unit 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 composed of a focusing lens or the like, and has an incident surface on which the laser light is incident and an exit surface on which the laser excitation light is output. The excitation light condensing unit 113 is optically coupled to the marker head 1 via the above-mentioned optical fiber cable. Therefore, the laser excitation light output from the excitation light condensing unit 113 is guided to the marker head 1 via the optical fiber cable.

The excitation light generation unit 110 can be an LD unit or an LD module in which the excitation light source driving unit 112, the excitation light source 111, and the excitation light condensing unit 113 are incorporated in advance. Further, the excitation light emitted from the excitation light generation unit 110 (specifically, the laser excitation light output from the excitation light condensing unit 113) can be unpolarized, thereby changing the polarization state. There is no need to consider it, 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 of the LD arrays in which dozens of LD elements are arranged by an optical fiber, has a mechanism for unpolarizing the output light. It is preferable to prepare.

(Other components)
The marker controller 100 also has a distance measuring unit 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 in the distance measuring light receiving unit 5B). Is said to be receivable.

Further, as will be described later, the laser processing apparatus L according to the present embodiment includes a non-coaxial camera 6 as a wide area camera for photographing the surface of the work W. The control unit 101 in the marker controller 100 can perform processing based on the image captured by the non-coaxial camera 6.

The marker controller 100 also includes a setting unit 107 for setting information related to the marking pattern. The setting contents in the setting unit 107 are read and used by the control unit 101 as the scanning control unit.

The distance measuring unit 103 and the setting unit 107 may be configured by the control unit 101. For example, the control unit 101 may use at least one of the distance measurement unit 103 and the setting unit 107.

Details of the distance measuring unit 103 and the setting unit 107 will be described later.

<Marker head 1>
As described above, the laser excitation light generated by the excitation light generation unit 110 is guided to the marker head 1 via the optical fiber cable. The marker head 1 irradiates the surface of the work W with the laser light output unit 2 that amplifies and generates the laser light based on the laser excitation light and outputs the laser light, and the laser light output from the laser light output unit 2. Distance measurement that is projected and received through the laser light scanning unit 4 that performs dimensional scanning, the laser light guiding unit 3 that constitutes the optical path from the laser light output unit 2 to the laser light scanning unit 4, and the laser light scanning unit 4. A distance measuring unit 5 for measuring the distance to the surface of the work W based on light is provided.

Here, the laser beam guide unit 3 according to the present embodiment not only constitutes an optical path, but also has 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. Etc., a plurality of members are combined.

Further, the laser light guide unit 3 further includes an upstream side merging mechanism (guide light merging mechanism) 31 that merges the near-infrared laser light output from the laser light output unit 2 and the guide light emitted from the guide light source 36. It has a downstream side merging mechanism (distance measuring light merging mechanism) 35 that merges the laser light guided to the laser light scanning unit 4 and the ranging light projected from the ranging unit 5.

3A to 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. Of FIGS. 3A to 3B, FIG. 3A illustrates a case where the work W is processed by using a near-infrared laser beam, and FIG. 3B shows a case where the distance to the surface of the work W is measured by using the distance measuring unit 5. Is illustrated.

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

In the following description, the longitudinal direction of the housing 10 in FIG. 4 is simply referred to as the "longitudinal direction" or the "front-back direction", and the lateral direction of the housing 10 in the figure is simply referred to as the "minor direction" or It may be called "left-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. Further, FIG. 6 is a cross-sectional view illustrating the configuration of the laser beam guiding unit 3, the laser beam scanning unit 4, and the ranging unit 5, and FIG. 7 is a cross-sectional view illustrating the configuration of the laser beam guiding unit 3, the laser beam scanning unit 4, and the ranging unit 5. FIG. 8 is a cross-sectional view illustrating the optical path connecting the laser beam guide unit 3, the laser beam scanning unit 4, and the distance measuring unit 5. FIG.

As illustrated in FIGS. 5 to 6, a partition portion 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 portion 11 is formed in a flat plate shape extending in a direction perpendicular to the longitudinal direction of the housing 10. Further, the partition portion 11 is arranged so as to be closer to one side in the longitudinal direction (front side in FIG. 4) than the central portion of the housing 10 in the same direction in the longitudinal direction of the housing 10.

Therefore, the space partitioned on one side in the longitudinal direction in the housing 10 has a shorter dimension in the longitudinal direction than the space partitioned on the other side in the longitudinal direction (rear side in FIG. 4). Hereinafter, the space in the housing 10 partitioned on the other side in the longitudinal direction is referred to as the first space S1, while the space partitioned on one side in the longitudinal direction is referred to as the second space S2.

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

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

More specifically, among the components constituting the laser beam output unit 2, the optical component 21 such as an optical lens and an optical crystal, which is required to be sealed as airtightly as possible, is the one in the short direction in the first space S1. In the space on the side, it is arranged inside the accommodation space surrounded by the base plate 12 and the like.

On the other hand, among the parts constituting the laser beam output unit 2, for parts that are not necessarily required to be sealed, such as electrical wiring and the heat sink 22 shown in FIG. 5, the base plate 12 is sandwiched between the optical parts 21. It is arranged on the opposite side (the other side in the lateral direction in 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 lateral direction with the base plate 12 interposed therebetween, similarly to the optical component 21 in the laser beam output unit 2. .. Specifically, the laser light scanning unit 4 according to this embodiment is arranged adjacent to the above-mentioned partition portion 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 lateral direction in the first space S1 like the heat sink 22 in the laser beam output unit 2.

Further, the parts constituting the laser beam guide unit 3 are mainly arranged in the second space S2. In this embodiment, most of the parts constituting the laser beam guide portion 3 are housed in a space surrounded by the partition portion 11 and the cover member 17 that partitions the front surface of the housing 10.

Among the parts constituting the laser beam guide unit 3, the downstream side merging mechanism 35 is arranged at a portion near the partition portion 11 in the first space S1 (see FIG. 5). That is, in this embodiment, the downstream merging mechanism 35 is located near the boundary between the first space S1 and the second space S2.

Further, the base plate 12 is formed with a through hole (not shown) that penetrates the base plate 12 in the plate thickness direction. Through this through hole, the laser beam guide unit 3, the laser beam scanning unit 4, and the distance measuring unit 5 are optically coupled. The base plate 12 has high rigidity, and even after many years of use, the base plate 12 is less likely to be deformed than the housing 10. Therefore, by fixing the distance measuring unit 5 to the base plate 12 instead of the housing 10 by using, for example, a fastening member such as a screw, it is possible to prevent the posture of the distance measuring unit 5 from shifting due to long-term use, and thus the distance measuring accuracy. Can be prevented from decreasing.

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

(Laser beam output unit 2)
The laser light output unit 2 generates a near-infrared laser light for printing processing based on the laser excitation light generated by the excitation light generation unit 110, and transfers the near-infrared laser light to the laser light guide unit 3. It is configured to output.

Specifically, the laser light output unit 2 generates laser light having a predetermined wavelength based on the laser excitation light, and amplifies the laser light to emit near-infrared laser light from the laser oscillator 21a and the laser oscillator 21a. It includes a beam sampler 21b for separating a part of the oscillated near-infrared laser light, and a power monitor 21c for incident the near-infrared laser light separated by the beam sampler 21b.

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

In particular, in this embodiment, a rod-shaped Nd: YVO ₄ (yttrium vanadate) is used as the laser medium. As a result, the laser oscillator 21a can emit a laser beam having a wavelength in the vicinity of 1064 nm (the above-mentioned near-infrared laser beam) as the laser beam. However, the present invention is not limited to this example, and as another laser medium, for example, rare earth-doped YAG, YLF, GdVO _{4 and the} like can be used. Various solid-state laser media can be used depending on the application of the laser processing apparatus L.

Further, it is also possible to combine a solid-state laser medium with a wavelength conversion element to convert the wavelength of the output laser light into an arbitrary wavelength. Further, a so-called fiber laser in which a fiber is used as an oscillator instead of the bulk may be used as the solid-state laser medium.

Further, a solid-state laser medium such as Nd: YVO ₄ and a fiber may be combined to form a laser oscillator 21a. 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 work W, while high output is realized as in the case of using a fiber. It is possible to realize faster printing processing.

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

(Laser beam guide 3)
The laser light guide unit 3 forms at least a part of the laser light path P that guides the near-infrared laser light emitted from the laser light output unit 2 to the laser light scanning unit 4. The laser light guide unit 3 includes a Z scanner (focus adjustment unit) 33, a guide light source (guide light emission unit) 36, and the like, in addition to the bend mirror 34 for forming such a laser optical path P. 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 unit 2 is reflected by the bend mirror 34 and passes through the laser light guide unit 3. On the way to the bend mirror 34, a Z scanner 33 for adjusting the focal position of the near-infrared laser beam is arranged. The near-infrared laser light that has passed through the Z scanner 33 and is reflected by the bend mirror 34 is incident on the laser light scanning unit 4.

The laser optical path P composed of the laser light guide unit 3 can be divided into two with the Z scanner 33 as the focus adjustment unit as a boundary. Specifically, the laser optical path P composed of the laser light guide unit 3 includes an upstream optical path Pu from the laser light output unit 2 to the Z scanner 33 and a downstream optical path Pd from the Z scanner 33 to the laser light scanning unit 4. Can be divided into.

More specifically, the upstream optical path Pu is provided inside the housing 10 and reaches the Z scanner 33 from the laser beam output unit 2 via the upstream side merging mechanism 31 described above.

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

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

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

-Guide light source 36-
The guide light source 36 is provided in the second space S2 inside the housing 10, and emits a guide light for projecting a predetermined processing pattern onto the surface of the work W. The wavelength band of the guide light is set so as to fall within the visible light range. As an example, the guide light source 36 according to the present embodiment emits a red laser beam having a wavelength in the vicinity of 655 nm as the guide light. Therefore, when the guide light is emitted from the marker head 1, the user can visually recognize the guide light.

Specifically, the wavelength band of the guide light in the present embodiment is preferably set to 645 nm or more and 660 nm or less. Therefore, the wavelength band of the guide light does not overlap with the near-infrared laser light wavelength band.

As described above, in the present embodiment, the wavelength of the guide light is set to be at least different from the wavelength of the near-infrared laser light. Further, as will be described later, the ranging light emitting unit 5A in the ranging unit 5 emits ranging light having a wavelength different from that of the guide light and the near-infrared laser light. Therefore, the ranging light, the guide light, and the laser light have different wavelengths, and the wavelength bands of the ranging light, the guide light, and the laser light do not overlap each other.

Further, the guide light source 36 is arranged at substantially the same height as the upstream side merging mechanism 31 in the second space S2, and emits a visible light laser (guide light) toward the inside in the lateral direction of the housing 10. be able to. The guide light source 36 is also arranged so that the optical axis of the guide light emitted from the guide light source 36 intersects with the upstream merging mechanism 31.

The term "substantially the same height" as used herein means that the height positions are substantially the same when viewed from the bottom plate 10a forming the lower surface of the housing 10. In other descriptions, it also refers to the height seen from the bottom plate 10a.

Therefore, for example, when the guide light is emitted from the guide light source 36 in order to make the user visually recognize the processing pattern by the near infrared laser light, the guide light reaches the upstream side merging mechanism 31. The upstream side 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 transmitted through the dichroic mirror and the near-infrared laser light reflected by the mirror merge and become coaxial.

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

-Upstream merging mechanism 31-
The upstream side merging mechanism 31 is provided inside the housing 10 in the middle of the laser optical path P from the laser light output unit 2 to the laser light scanning unit 4, starting from the laser light output unit 2. The upstream side merging mechanism 31 is an example of the "guide optical merging mechanism" in the present embodiment.

Specifically, the upstream side merging mechanism 31 according to the present embodiment is a portion (specifically, the above-mentioned upstream) between the laser light output unit 2 and the Z scanner 33 as the focus adjustment unit in the laser optical path P. It is arranged in the side optical path Pu).

The upstream side merging mechanism 31 merges the guide light emitted from the guide light source 36 as the guide light emitting portion with the upstream side optical path Pu in the laser optical path P. By providing the upstream side merging mechanism 31, the guide light emitted from the guide light source 36 and the near infrared laser light in the upstream side optical path Pu can be made coaxial.

As described above, the wavelength band of the guide light is set so as not to overlap with at least the wavelength band of the near-infrared laser light. Therefore, the upstream side merging mechanism 31 can be configured by using, for example, a dichroic mirror as described above. The near-infrared laser light and the guide light coaxialized by the dichroic mirror propagate downward, pass through the Z scanner 33, and reach the bend mirror 34.

-Z scanner 33-
The Z scanner 33 as the focus adjustment unit is arranged in the middle of the optical path formed by the laser light guide unit 3, and can adjust the focal position of the near-infrared laser light emitted from the laser light output unit 2. ..

Specifically, the Z scanner 33 is provided inside the housing 10 in the middle of the optical path from the upstream side merging mechanism 31 as the guide light merging mechanism to the laser light scanning unit 4 in the laser optical path P.

Specifically, as shown in FIGS. 3A to 3B, the Z scanner 33 according to the present embodiment passes through the incident lens 33a that transmits the near-infrared laser light emitted from the laser light output unit 2 and the incident lens 33a. A collimating lens 33b that passes the near-infrared laser light, an emitting lens 33c that passes the near-infrared laser light that has passed through the incident lens 33a and the collimating lens 33b, and a lens driving unit 33d that moves the incident lens 33a. It has a lens 33a, a collimating lens 33b, and a casing 33e for accommodating the exit lens 33c.

The incident lens 33a is made of a plano-concave lens, and the collimating lens 33b and the emitting lens 33c are made of a plano-convex lens. The incident lens 33a, the collimating lens 33b, and the emitting lens 33c are arranged so that their optical axes are coaxial with each other.

Further, in the Z scanner 33, the lens driving unit 33d moves the incident lens 33a along the optical axis. As a result, the relative distance between the incident lens 33a and the emitted lens 33c is changed while keeping the optical axes of the incident lens 33a, the collimating lens 33b, and the emitting lens 33c coaxial with each other with respect to the near-infrared laser light passing through the Z scanner 33. can do. As a result, the focal position of the near-infrared laser beam applied to the work W changes.

Hereinafter, each part constituting the Z scanner 33 will be described in more detail.

The casing 33e has a substantially cylindrical shape. As shown in FIGS. 3A to 3B, openings 33f for passing near-infrared laser light are formed at both ends of the casing 33e. Inside the casing 33e, the incident lens 33a, the collimating lens 33b, and the emitting lens 33c are arranged in this order in the vertical direction.

Among the incident lens 33a, the collimating lens 33b, and the emitting lens 33c, the collimating lens 33b and the emitting lens 33c are fixed inside the casing 33e. On the other hand, the incident lens 33a is provided so as to be movable in the vertical direction. The lens driving unit 33d has, for example, a motor, and moves the incident lens 33a in the vertical direction. As a result, the relative distance between the incident lens 33a and the outgoing lens 33c is changed.

For example, it is assumed that the distance between the incident lens 33a and the outgoing lens 33c is adjusted to be relatively short by the lens driving unit 33d. In this case, since the focusing angle of the near-infrared laser beam passing through the emitting lens 33c is relatively small, the focal position of the near-infrared laser beam is moved away from the transmission window 19 of the marker head 1.

On the other hand, it is assumed that the distance between the incident lens 33a and the outgoing lens 33c is adjusted to be relatively long by the lens driving unit 33d. In this case, since the focusing angle of the near-infrared laser beam passing through the emitting lens 33c becomes relatively large, the focal position of the near-infrared laser beam approaches the transmission window 19 of the marker head 1.

In the Z scanner 33, of the incident lens 33a, the collimating lens 33b, and the emitting lens 33c, the incident lens 33a is fixed inside the casing 33e so that the collimating lens 33b and the emitting lens 33c can be moved in the vertical direction. good. Alternatively, the incident lens 33a, the collimating lens 33b, and the emitting lens 33c may all be movable in the vertical direction.

In this way, the Z scanner 33 as the focus adjusting unit functions as a means for scanning the near-infrared laser beam in the vertical direction. Hereinafter, the scanning direction by the Z scanner 33 may be referred to as "Z direction".

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.

The Z-scanner 33 according to the present embodiment, particularly the lens driving unit 33d in the Z-scanner 33, is configured to operate based on the control signal output from the control unit 101.

-Bend mirror 34-
The bend mirror 34 is provided in the middle of the downstream optical path Pd, and is arranged so as to bend the optical path Pd and direct it rearward. As shown in FIG. 6, the bend mirror 34 is arranged at substantially the same height as the optical member 35a in the downstream merging 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 merging mechanism 35, and reach the laser light scanning unit (specifically, the first scanner 41) 4. ..

-Downstream side merging mechanism 35-
The downstream side merging mechanism 35 is provided inside the housing 10 in the laser optical path P between the upstream side merging mechanism 31 as a guide light merging mechanism and the laser light scanning unit 4. The downstream side merging mechanism 35 is an example of the “distance measuring light merging mechanism”.

Specifically, the downstream merging mechanism 35 according to the present embodiment is a portion (specifically, the above-mentioned downstream) between the Z scanner 33 as the focus adjustment unit and the laser light scanning unit 4 in the laser optical path P. It is arranged in the side optical path Pd).

The downstream merging mechanism 35 can merge the ranging light emitted from the ranging light emitting unit 5A in the ranging unit 5 with the intermediate portion of the laser optical path P. The ranging light that has merged with the intermediate portion is guided to the surface of the work W via the laser beam scanning unit 4.

In addition, the downstream merging mechanism 35 measures the ranging light reflected by the work W (particularly, the surface of the work W) and returns to the downstream optical path Pd via the laser beam scanning unit 4 in the ranging unit 5. It can be guided to the distance light receiving unit 5B.

By providing the downstream side merging mechanism 35, the distance measuring light emitted from the distance measuring light emitting unit 5A can be made coaxial with the near infrared laser light and the guide light in the downstream side optical path Pd. At the same time, by providing the downstream side merging mechanism 35, among the ranging light emitted from the marker head 1 and reflected by the work W, the ranging light returned to the marker head 1 is guided to the ranging light receiving unit 5B. be able to.

The configuration of the downstream merging mechanism 35 will be described later.

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

In the example shown in FIG. 5, the laser light scanning unit 4 is configured as a so-called biaxial galvano scanner. That is, the laser light scanning unit 4 includes a first scanner 41 for scanning the near-infrared laser light incident from the laser light guiding unit 3 in the first direction, and a near-infrared laser scanned by the first scanner 41. It has 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 beam in a direction substantially orthogonal to the first scanner 41. In the present embodiment, the first direction is equal to the front-rear direction (longitudinal direction of the housing 10), and the second direction is equal to the left-right direction (short direction of the housing 10). Hereinafter, the first direction is referred to as "X direction", and the second direction orthogonal to this is referred to as "Y direction". Both the X and Y directions are orthogonal to the Z direction described above.

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

The first mirror 41a is also rotationally driven by a motor (not shown) built into 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 reflection angle of the near-infrared laser light 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 arranged 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 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) built into the second scanner 42. This motor can rotate the second mirror 42a around a rotation axis extending in the front-rear direction. By adjusting the rotational posture of the second mirror 42a, the reflection angle 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 side merging mechanism 35, the near-infrared laser light is transmitted to the first mirror 41a in the first scanner 41 and the second mirror in the second scanner 42. It is reflected in order by the 42a and is emitted to the outside of the marker head 1 through the transmission window 19.

At that time, by operating the motor of the first scanner 41 and adjusting the rotational posture of the first mirror 41a, it becomes possible to scan the near-infrared laser beam in the first direction on the surface of the work W. .. At the same time, by operating the motor of the second scanner 42 to adjust the rotational posture of the second mirror 42a, it becomes possible to scan the near-infrared laser beam in the second direction on the surface of the work W.

Further, as described above, the laser beam scanning unit 4 is provided with not only the near-infrared laser beam but also the guide light that has passed through the optical member 35a of the downstream merging mechanism 35 or the distance measuring light reflected by the member 35a. Will also be incident. The laser light scanning unit 4 according to the present embodiment can two-dimensionally scan the incident guide light or ranging light by operating the first scanner 41 and the second scanner 42, respectively.

The rotational posture that the first mirror 41a and the second mirror 42a can take is basically that when the near-infrared laser light is reflected by the second mirror 42a, the reflected light passes through the transmission window 19. It is set within such a range (see also FIGS. 7 to 8).

In this way, the laser beam scanning unit 4 according to the present embodiment is electrically controlled by the control unit 101 as a scanning control unit, so that the near-infrared laser light is applied to the processing region set on the surface of the work W. By irradiating, a predetermined processing pattern (marking pattern) can be formed in the processing region.

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

The ranging unit 5 is mainly classified into a module for projecting the ranging light and a module for receiving the ranging light. Specifically, the distance measuring unit 5 includes a distance measuring light emitting unit 5A configured as a module for projecting distance measuring light, and a distance measuring light receiving unit configured as a module for receiving distance measuring light. It is equipped with 5B.

Of these, the ranging light emitting unit 5A is provided inside the housing 10, and the ranging light for measuring the distance from the marker head 1 to the surface of the work W in the laser processing apparatus L is the laser beam. It emits light toward the scanning unit 4.

On the other hand, the distance measuring light receiving unit 5B is provided inside the housing 10 like the distance measuring light emitting unit 5A, and is reflected on the surface of the work W to be reflected on the surface of the work W, and the laser light scanning unit 4 and the downstream side merging mechanism 35. Receives the range-finding light returned via.

Further, the distance measuring unit 5 includes a support base 50 that supports the distance measuring light emitting unit 5A and the distance measuring light receiving unit 5B from below, and is fixed to the inside of the housing 10 via the support base 50. There is.

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

Further, the distance measuring unit 5 is optically coupled to the laser beam guiding unit 3 via the above-mentioned optical member 35a. As described above, the distance measuring unit 5 projects the distance measuring light along the longitudinal direction of the housing 10. On the other hand, the optical member 35a reflects the ranging light propagating along the lateral direction of the housing 10 instead of the longitudinal direction.

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

Therefore, the ranging light incident on the bend mirror 59 from the ranging light emitting unit 5A is incident on the optical member 35a reflected by the mirror 59. On the other hand, the distance measuring light returned to the laser light scanning unit 4 and reflected by the optical member 35a is incident on the bend mirror 59, and is reflected by the mirror 59 and incident on the distance measuring light receiving unit 5B.

Hereinafter, the configurations of the respective parts forming the distance measuring unit 5 will be described in order.

-Distance measuring light emitting part 5A-
The ranging light emitting unit 5A is provided inside the housing 10, and is configured to emit ranging 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 is a pair of the distance measuring light source 51 and the light projecting lens 52 described above, a casing 53 accommodating them, and a pair of distance measuring lights focused by the light projecting lens 52. It has guide plates 54L and 54R. The distance measuring light source 51, the light projecting lens 52, and the guide plates 54L and 54R are arranged in order from the rear side of the housing 10, and the arrangement direction thereof 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 the ranging light source 51 is formed on one side in the same direction, that is, at one end corresponding to the rear side of the housing 10. Is attached, while the light projecting 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 light projecting lens 52 is sealed in a substantially airtight manner.

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

Specifically, the wavelength band of the ranging light in the present embodiment is preferably set to 680 nm or more and 695 nm or less. Therefore, the wavelength band of the ranging light does not overlap with the wavelength band of the near infrared laser light and the guide light.

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

The light projecting lens 52 is located between the pair of light receiving elements 56L and 56R in the ranging light receiving unit 5B and the light receiving lens 57 in the longitudinal direction of the support base 50. The projection lens 52 is arranged so that the optical axis Ao of the ranging light passes through.

The projectile lens 52 can be, for example, a plano-convex lens, and the spherical convex surface can be fixed in a posture facing the outside of the casing 53. The light projecting lens 52 collects the ranging light emitted from the ranging light source 51 and emits it to the outside of the casing 53. The ranging light emitted to the outside of the casing 53 reaches between the guide plates 54L and 54R.

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

Therefore, the ranging light emitted from the ranging light source 51 passes through the space inside the casing 53, the central portion of the projection lens 52, and the space between the guide plates 54L and 54R, and goes to the outside of the ranging unit 5. It is output. The distance measuring light output in this way is reflected by the bend mirror 59 and the optical member 35a in the downstream side merging mechanism 35, and is incident on the laser light scanning unit 4.

The ranging 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 is reflected from the transmission window 19 to the outside of the marker head 1. Will be emitted to.

As described in the description of the laser light scanning unit 4, by adjusting the rotational posture of the first mirror 41a of the first scanner 41, the ranging light can be scanned in the first direction on the surface of the work W. .. At the same time, by operating the motor of the second scanner 42 to adjust the rotational posture of the second mirror 42a, it becomes possible to scan the ranging light in the second direction on the surface of the work W.

The ranging light thus scanned is reflected on the surface of the work W. A part of the distance measuring light reflected in this way (hereinafter, this is also referred to as “reflected light”) is incident on the inside of the marker head 1 through the transmission window 19. The reflected light incident on the inside of the marker head 1 returns to the laser light guide unit 3 via the laser light scanning unit 4. Since the reflected light has the same wavelength as the distance measuring light, it is reflected by the optical member 35a of the downstream side merging mechanism 35 in the laser light guide unit 3 and is incident on the distance measuring unit 5 via the bend mirror 59.

-Distance measuring light receiver 5B-
The ranging light receiving unit 5B is provided inside the housing 10 and receives the ranging light (equivalent to the above-mentioned “reflected light”) emitted from the ranging light emitting unit 5A and reflected by the work W. It is configured to do.

Specifically, the ranging light receiving unit 5B has a pair of light receiving elements 56L and 56R and a light receiving lens 57. The pair of light receiving elements 56L and 56R are respectively arranged at the rear end portion of the support base 50, while the light receiving lens 57 is arranged at the front end portion of the support base 50, respectively. Therefore, the pair of light receiving elements 56L and 56R and the light receiving lens 57 are substantially arranged along the longitudinal direction of the housing 10 and the support base 50.

The optical axes of 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 ranging light in the ranging light emitting unit 5A. The pair of light receiving elements 56L and 56R receive the reflected light returned to the laser light scanning unit 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 ranging light emitting unit 5A. In this embodiment, the arrangement direction of the pair of light receiving elements 56L and 56R is equal to the lateral direction of the housing 10 and the support base 50, that is, the left-right 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.

Each of the pair of light receiving elements 56L and 56R has a light receiving surface oriented obliquely forward, detects a light receiving position of reflected light on each light receiving surface, and indicates a signal (detection signal) indicating the detection result. Is output. The detection signals output from the light receiving elements 56L and 56R are input to the marker controller 100 and reach the distance measuring unit 103.

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

In the present embodiment, the light receiving elements 56L and 56R are configured by 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) thereof. That is, when the light receiving elements 56L and 56R are configured by using the CMOS image sensor, the pixels are arranged at least in the left-right direction on each light receiving surface. In this case, each of the light receiving elements 56L and 56R can read 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.

When each light receiving element 56L, 56R is configured by using an element capable of detecting the light receiving amount distribution (light receiving waveform) such as a CMOS image sensor, the magnitude of the light receiving amount in each light receiving element 56L, 56R is measured. The intensity of the distance light, that is, the intensity of the distance measurement light emitted from the distance measurement light emitting unit 5A (hereinafter, this is also referred to as “projected light amount”) and the gain when amplifying the signal for each pixel (hereinafter, this is referred to as this). It can also be adjusted using “light receiving gain”). In addition to the gain, the exposure time of each of the light receiving elements 56L and 56R can be used for adjustment.

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 received amount of the reflected light. As an index indicating the received light amount, for example, the height of the peak in the received light amount distribution of the reflected light can be used. Instead of this, the total value, the average value, and the integrated value of the received light amount distribution may be used.

Further, as an index indicating the light receiving position of the reflected light, the peak position of the light receiving amount distribution (the peak position of the spot) is used in this embodiment, but instead of this, the center of gravity position of the light receiving amount distribution may be used. good.

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 from the downstream side merging mechanism 35 to the pair of light receiving elements 56L and 56R, and the reflected light passing through the downstream side merging mechanism 35 is transmitted to the pair of light receiving elements 56L and 56R, respectively. Can be focused on the light receiving surface of.

The light receiving lens 57 collects the reflected light returned to the laser light scanning unit 4 and forms a spot of the reflected light on the light receiving surface of each of the light receiving elements 56L and 56R. Each of the light receiving elements 56L and 56R outputs a signal indicating the peak position of the spot thus formed and the light receiving amount to the distance measuring unit 103.

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

-About the distance measurement method-
FIG. 9 is a diagram illustrating a triangular ranging method. In FIG. 9, only the distance measuring unit 5 is shown, but the following description is also common to the case where the distance measuring light is emitted via the laser beam scanning unit 4 as described above.

As illustrated in FIG. 9, when the distance measuring light is emitted from the distance measuring light source 51 in the distance measuring light emitting unit 5A, the distance measuring light is emitted to the surface of the work W. When the ranging light is reflected by the work W, the reflected light (particularly diffuse reflected light) propagates substantially isotropically if the influence of specular reflection is removed.

Although the reflected light propagating in this way contains a component incident on the light receiving element 56L via the light receiving lens 57, the incident light is transmitted to the light receiving element 56L according to the distance between the marker head 1 and the work W. The angle of incidence will increase or decrease. When the angle of incidence on the light receiving element 56L increases or decreases, the light receiving position on the light receiving surface 56a is displaced.

As described above, the distance between the marker head 1 and the work W and the light receiving position on the light receiving surface 56a are related to each other 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 work W can be calculated from the light receiving position on the light receiving surface 56a. Such a calculation method is nothing but a method using a so-called triangular ranging method.

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

Specifically, the above-mentioned condition setting storage unit 102 stores in advance the relationship between the light receiving position on the light receiving surface 56a and the distance from the marker head 1 to the surface of the work W. On the other hand, a signal indicating the light receiving position of the distance measuring light in the distance measuring light receiving unit 5B, specifically, the reflected light of the distance measuring light and the peak position of the spot formed on the light receiving surface 56a is input to the distance measuring unit 103. Will be done.

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

For example, the laser machining apparatus L automatically or manually determines a portion (printing point) to be machined by the marker head 1 on the surface of the work W. Subsequently, the laser processing apparatus L measures the distance to each printing point (more accurately, the distance measuring point set around the printing point) prior to executing the printing processing, and matches the measured distance. The control parameter of the Z scanner 33 is determined so as to be the focal position. The laser processing apparatus L operates the Z scanner 33 based on the control parameters thus determined, and then prints the work W with the near-infrared laser beam.

<Work W processing procedure>
Hereinafter, the processing procedure of the work W by the laser processing apparatus L will be described as a specific use example of the near-infrared laser light, the ranging light, and the guide light. FIG. 10 is a flowchart illustrating a machining procedure of the work W.

The control process illustrated in FIG. 10 is executed by a 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 ranging light emitting unit 5A, and the guide light source 36. It is possible.

First, in step S101, the processing conditions in laser processing are set by the user operating the operation terminal 800. The processing conditions set in step S101 include, for example, a character string to be printed on the surface of the work W, the content of a figure (marking pattern), and a layout of such a character string or the like.

In the following step S102, the control unit 101 determines a portion of the surface of the work W where the distance from the marker head 1 should be measured (hereinafter, also referred to as “measurement location”) based on the machining conditions set in step S101. Determine in multiple places.

In the following step S103, the control unit 101 measures the distance from the laser processing device 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 this 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 the step S102, and emits the reflected light to the distance measuring light receiving unit 5B. To receive light. Then, a signal indicating the light receiving position of the reflected light in the distance measuring light receiving unit 5B is input to the distance measuring unit 103, and the distance measuring unit 103 measures the distance to the surface of the work W. The distance measuring unit 103 inputs a signal indicating the measured distance to the control unit 101.

In the following step S104, the control unit 101 determines the control parameters of the Z scanner 33 so as to have a focal position commensurate with each measured value based on the measurement result in step S103, that is, the measured value of the distance at each measurement point. ..

Specifically, in this step S104, the control unit 101 determines the control parameter of the lens driving unit 33d at each measurement point, that is, the relative distance between the incident lens 33a and the emitting lens 33c at each measurement point.

Both the upstream side merging mechanism 31 and the downstream side merging mechanism 35 are arranged on the way from the laser light output unit 2 to the laser light scanning unit 4. Then, the upstream side merging mechanism 31 coaxializes the optical axes of the guide light and the near-infrared laser light, and the downstream side merging mechanism 35 coaxializes the optical axes of the distance measuring light and the near-infrared laser light. Therefore, by controlling the laser light scanning unit 4 by the control unit 101, not only the near-infrared laser light but also the guide light and the ranging light can be two-dimensionally scanned.

As an example of the two-dimensional scanning of the guide light by the laser light scanning unit 4, the control unit 101 executes step S105 following step S104. Specifically, in step S105, the control unit 101 adjusts the focal position at each measurement point via the Z scanner 33, and after adjusting the focal position by the Z scanner 33, the work W via the guide light source 36. The surface of the surface is irradiated with guide light. At the same time, the control unit 101 controls the laser light scanning unit 4 to trace the marking pattern by the guide light emitted from the guide light source 36.

The upstream side 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. Therefore, by adjusting the focal position of the near-infrared laser light with the Z scanner 33, it is possible to adjust not only the near-infrared laser light but also the focal position of the guide light.

Further, the tracing of the marking pattern by the guide light is repeatedly performed by appropriately controlling the laser light scanning unit 4. As a result, the marking pattern is continuously displayed on the surface of the work W due to the afterimage action of the human eye. At this time, in order to make the continuous display by the afterimage action effective, it is conceivable to set the scanning speed of the guide light to be equal to or higher than the minimum speed at which the afterimage phenomenon occurs. On the other hand, depending on the material of the work W, the output of the near-infrared laser beam, and the like, the scanning speed of the near-infrared laser beam may become excessively slow during the printing process. In response to this, the scanning speed of the guide light is set to be 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 the following step S106, the control unit 101 completes the setting related to the marking pattern, and executes the printing process based on the setting. Instead of step S106, the setting related to the marking pattern may be transferred to the condition setting storage unit 102 or the operation terminal 800 and stored.

As described above, the laser processing apparatus L according to the present embodiment has the guide light and the distance measuring light in addition to the near infrared laser light by making both the guide light and the distance measuring light coaxial with the laser optical path P. It enables two-dimensional scanning of light.

However, if the distance measuring unit 5 is also coaxial with the guide light source 36 coaxial with the laser optical path P, at least a part of the distance measuring light reflected on the surface of the work W is the distance measuring unit 5. Instead, it returns to the guide light source 36, and there is a possibility that the amount of light received by the distance measuring light receiving unit 5B in the distance measuring unit 5 decreases. Such a decrease in the amount of received light is inconvenient because it causes a decrease in measurement accuracy.

As a result of diligent studies, the inventors of the present application have devised a configuration of the downstream side merging mechanism 35 as a distance measuring light merging mechanism in which the distance measuring light, the guide light, and the near infrared laser light are merged. So, I came to overcome the above-mentioned inconvenience.

Hereinafter, the configuration of the downstream side merging mechanism 35 will be described in detail.

<About the configuration of the downstream merging mechanism 35>
FIG. 11 is a perspective view illustrating the configuration of the downstream merging mechanism 35 when viewed from the rear, and FIG. 12 is a perspective view illustrating the configuration of the downstream merging mechanism 35 when viewed from the front. Further, FIG. 13A is a diagram illustrating the reflectance of the laser beam incident surface 351 according to the first embodiment, and FIG. 13B is a diagram illustrating the reflectance of the laser light emitting surface 352 according to the first embodiment. be. Further, FIG. 14A is a diagram illustrating an optical path of the near-infrared laser light and the guide light in the downstream merging mechanism 35, and FIG. 14B is a diagram illustrating an optical path of the ranging light in the downstream merging mechanism 35. ..

As described above, the wavelength band of the ranging light is set so as not to overlap with the wavelength band of the near-infrared laser light and the guide light. Therefore, the downstream side merging mechanism 35 can be configured by using an optical member 35a made of a dichroic mirror or the like, similarly to the upstream side merging mechanism 31.

Specifically, the downstream side merging mechanism 35 as the distance measuring light upstream merging mechanism has, as main components, an optical member 35a that guides the distance measuring light reflected on the surface of the work W to the distance measuring light receiving unit 5B. It has a holder 35b that holds the optical member 35a and is fixed to the housing 10.

Then, the optical member 35a forming the downstream side merging mechanism 35 selectively reflects or transmits only the wavelength band of the ranging light from the wavelength bands of the near infrared laser light, the guide light, and the ranging light. , The distance measuring light can be guided to the distance measuring light receiving unit 5B.

Specifically, the optical member 35a is made of substantially disk-shaped glass, and the surface of the glass is coated so as to selectively reflect or transmit only the wavelength band of the ranging light. .. Here, on the front and back surfaces of the optical member 35a, as illustrated in FIGS. 14A and 14B, a laser light incident surface 351 on which the near-infrared laser light and the guide light are incident, and a near-red incident surface 351 incident on the laser light incident surface 351. A laser light emitting surface 352, which emits the external laser light and the guide light through the optical member 35a, is provided.

The coating treatment described above comprises, for example, a thin-film deposition treatment, and is applied to both the laser light incident surface 351 and the laser light emitting surface 352. By this coating treatment, the optical member 35a according to the present embodiment (particularly, the first embodiment) selectively reflects only the ranging light, while transmitting the wavelength bands of the near-infrared laser light and the guide light. be able to.

Further, the holder 35b is formed in a substantially tubular shape, and a substantially disk-shaped optical member 35a can be fitted to fix the holder 35b. As illustrated in FIGS. 6 and 7, the holder 35b is fitted into a through hole 11a provided in the partition portion 11. The through hole 11a communicates the second space S2 and the first space S1, and by fitting the holder 35b into the through hole 11a, the laser light guide unit 3 and the laser light scanning unit 4 are optically inserted. Can be combined.

More specifically, the holder 35b is arranged at substantially the same height as the second bend mirror 34 and behind the second bend mirror 34, and the housing 10 is provided with respect to the through hole 12a provided in the base plate 12. It is placed on the left side in the lateral direction of.

As shown in FIG. 6 and the like, the holder 35b is also fixed in a posture in which the optical axis of the optical member 35a is tilted diagonally rearward to the right (particularly, a posture tilted 45 degrees in the front-rear direction). As a result, the mirror surface on one side of the optical member 35a (the laser light incident surface 351 described later) is directed to the second bend mirror 34, and the mirror surface on the other side of the optical member 35a (the laser light emitting surface 352 described later) is directed to the second bend mirror 34. , It is designed to be directed to the through hole 12a of the base plate 12.

Therefore, as shown in FIGS. 14A and 14B, the near-infrared laser light and the guide light are incident on the mirror surface (laser light incident surface 351) on one side of the optical member 35a through the through hole 11a of the partition portion 11. On the other hand, the distance measuring light is incident on the mirror surface (laser light emitting surface 352) on the other side through the through hole 12a.

The specific reflectance of the optical member 35a is as illustrated in FIGS. 13A and 13B. The part surrounded by the broken line in each figure exemplifies the wavelength bands of the guide light, the ranging light, and the near-infrared laser light (laser light for printing).

As shown in FIGS. 13A and 13B, both the laser light incident surface 351 and the laser light emitting surface 352 according to the first embodiment are configured to transmit the wavelength bands of the guide light and the near infrared laser light. ing.

Specifically, the optical member 35a according to the first embodiment has a reflectance corresponding to each wavelength band of the guide light and the near-infrared laser light on both the laser light incident surface 351 and the laser light emitting surface 352. It is set to substantially 0%. With this setting, the guide light and the near-infrared laser light incident on the laser beam incident surface 351 pass through the laser beam incident surface 351. The guide light and the near-infrared laser light that have passed through the laser light incident surface 351 pass through the inside of the optical member 35a while refracting, and reach the laser light emitting surface 352. The guide light and the near-infrared laser light that have reached the laser light emitting surface 352 pass through the laser light incident surface 351 and are emitted to the outside (see FIG. 14A). The guide light and the near-infrared laser light thus emitted are applied to the surface of the work W via the laser light scanning unit 4.

On the other hand, as shown in FIG. 13B, the laser beam emitting surface 352 according to the first embodiment selectively reflects only the wavelength band of the ranging light. On the other hand, the laser beam emitting surface 352 according to the first embodiment is configured to transmit the wavelength band of the ranging light as shown in FIG. 13A.

Specifically, the optical member 35a according to the first embodiment has a reflectance corresponding to the wavelength band of the ranging light of substantially 100% on the laser beam emitting surface 352 (more specifically, 95% or more 100). %) Is set. With this setting, most of the ranging light incident on the laser beam emitting surface 352 is reflected by the laser beam emitting surface 352 (see FIG. 14B). The distance-finding light reflected in this way becomes coaxial with the guide light and the near-infrared laser light, and is applied to the surface of the work W via the laser light scanning unit 4. The ranging light reflected by the surface returns to the optical member 35a via the laser beam scanning unit 4, is reflected again by the laser beam emitting surface 352, and returns to the ranging unit 5.

However, it is not technically easy to set the reflectance of the laser beam emitting surface 352 to exactly 100%. Therefore, a very small part of the ranging light incident on the laser beam emitting surface 352 passes through the laser beam emitting surface 352 without being reflected by the laser beam emitting surface 352. The ranging light that has passed through the laser beam emitting surface 352 passes through the inside of the optical member 35a while refracting, and reaches the laser beam incident surface 351.

Here, in the optical member 35a according to the first embodiment, the reflectance corresponding to the wavelength band of the ranging light is substantially 0% (more specifically, 0% or more and 5%) on the laser beam incident surface 351. Less than). With this setting, the distance measuring light that has passed through the laser light emitting surface 352 and reached the laser light incident surface 351 is suppressed from being reflected by the laser light incident surface 351 and is emitted to the outside from the laser light incident surface 351. Become so.

As shown in FIG. 7, both the ranging light incident on the laser beam emitting surface 352 from the ranging unit 5 and the ranging light reflected by the laser beam emitting surface 352 and returning to the ranging unit 5 are both. Both propagate along the left-right direction (the lateral direction of the housing 10) when the housing 10 is viewed in a plan view. This propagation direction is orthogonal to the propagation direction of the near-infrared laser light and the guide light propagating from the laser light guide unit 3 to the laser light scanning unit 4.

<About the effect of the downstream merging mechanism 35>
As described above, the guide light and the distance measuring light are respectively coaxial with the near-infrared laser light for processing, and the guide light and the distance measuring light can be scanned by the laser light scanning unit 4. There is.

Specifically, the upstream side merging mechanism 31 as the guide light merging mechanism is arranged in the middle of the laser optical path P connecting the laser light output unit 2 and the laser light scanning unit 4, and is downstream as the ranging light merging mechanism. The side merging mechanism 35 is arranged between the upstream merging mechanism 31 and the laser light scanning unit 4 in the laser light path P. When arranged in this way, the ranging light reflected on the surface of the work W and returned to the marker head 1 reaches the downstream merging mechanism 35 before reaching the upstream merging mechanism 31.

Here, as illustrated in FIG. 13B, the optical member 35a constituting the downstream merging mechanism 35 is of the wavelength band of the near-infrared laser light for processing, the guide light, and the distance-finding light. It is configured to guide the ranging light to the ranging light receiving unit 5B by selectively reflecting or transmitting only the wavelength band. With such a configuration, it is possible to suppress the propagation of the ranging light (particularly, the reflected light of the ranging light) to the guide light source 36 and increase the amount of received light in the ranging light receiving unit 5B. This makes it possible to suppress a decrease in measurement accuracy.

Further, as illustrated in FIG. 14B, the laser light emitting surface 352 of the optical member 35a may reflect the distance measuring light and guide the distance measuring light to the laser light scanning unit 4 or the distance measuring light receiving unit 5B. can. However, it is not technically easy to set the reflectance of the laser beam emitting surface 352 to exactly 100%, as illustrated in FIG. 13B. Therefore, a very small part of the ranging light incident on the laser beam emitting surface 352 passes through the laser beam emitting surface 352 without being reflected by the laser beam emitting surface 352. The ranging light that has passed through the laser beam emitting surface 352 passes through the inside of the optical member 35a while refracting, and reaches the laser beam incident surface 351.

If the distance measuring light that has reached the laser light incident surface 351 is reflected by the laser light incident surface 351 and returns to the distance measuring light receiving unit 5B, the laser light is emitted to the distance measuring light receiving unit 5B. The ranging light reflected by the surface 352 and the laser light incident surface 351 will both return. In this case, the light receiving position in the ranging light receiving unit 5B may be blurred. This is not desirable because it causes a decrease in measurement accuracy.

Therefore, as illustrated in FIG. 13A, the laser beam incident surface 351 transmits the wavelength band of the ranging light without reflecting it. As a result, the distance measuring light that has passed through the laser beam emitting surface 352 and reached the laser beam incident surface 351 is suppressed from being reflected by the laser beam incident surface 351 so that it is emitted to the outside from the laser beam incident surface 351. Become. As a result, blurring of the light receiving position in the distance measuring light receiving unit 5B can be suppressed, and deterioration of measurement accuracy can be suppressed.

Further, as illustrated in FIGS. 3A and 3B, the downstream merging mechanism 35 is arranged between the Z scanner 33 and the laser beam scanning unit 4, and is combined with the distance measuring light emitted from the distance measuring light emitting unit 5A. , Makes the laser beam that has passed through the Z scanner 33 coaxial. Therefore, since the distance measuring light is coaxialized in the optical path on the upstream side of the laser light scanning unit 4, the distance measuring light can be scanned by operating the laser light scanning unit 4.

At the same time, the ranging light is coaxialized in the optical path on the downstream side of the Z scanner 33. Therefore, it is possible to secure the measurement resolution by the distance measuring light without making the opening of the Z scanner 33 excessively large.

Further, as illustrated in FIG. 3B, not only the ranging light emitted from the ranging light emitting unit 5A but also the ranging light reflected by the work W and received by the ranging light receiving unit 5B is also the Z scanner 33. Does not pass. Therefore, the distance measuring light emitting unit 5A and the distance measuring light receiving unit 5B can be arranged close to each other, and the influence of distortion of the housing due to the temperature change can be suppressed. This is effective in ensuring the accuracy of measuring the distance by the distance measuring unit 103.

Further, as illustrated in FIG. 3A, the guide light emitted from the guide light source 36 includes the upstream side merging mechanism 31, the Z scanner 33, the downstream side merging mechanism 35, and the laser light scanning unit 4 in order. It passes through and is irradiated to the work W.

Here, the upstream side merging mechanism 31 is provided between the laser light output unit 2 and the Z scanner 33, and the guide light emitted from the guide light source 36 and the laser light emitted from the laser light output unit 2 And make it coaxial. Therefore, since the guide light and the laser light merge in the optical path on the upstream side of the Z scanner 33, the focal position of the guide light can be adjusted by operating the Z scanner 33. This makes it possible to improve the visibility of the guide light.

<< Second Embodiment >>
First, the laser processing system S including the first embodiment of the laser processing apparatus L will be described. In the following description, the second embodiment is simply referred to as the present embodiment, except when emphasizing that the configuration is peculiar to the second embodiment. Further, the description of the configuration common to the first embodiment will be omitted as appropriate.

FIG. 15A is a diagram corresponding to FIG. 3A illustrating the marker head 1 ′ according to the second embodiment of the laser processing apparatus L, and FIG. 15B illustrates the marker head 1 ′ according to the second embodiment of the laser processing apparatus L. It is a figure corresponding to FIG. 3B. Further, FIG. 16A is a diagram corresponding to FIG. 13A illustrating the reflectance of the laser beam incident surface 351'according to the second embodiment, and FIG. 16B is a diagram corresponding to FIG. 13A, and FIG. 16B shows the reflectance of the laser beam emitting surface 352' according to the second embodiment. It is a diagram corresponding to FIG. 13B illustrating the above. Further, FIG. 17A is a diagram corresponding to FIG. 14A illustrating the optical path of the near-infrared laser beam and the guide light in the second embodiment, and FIG. 17B is FIG. 14B illustrating the optical path of the ranging light in the second embodiment. It is a correspondence diagram.

The optical member 35a according to the second embodiment selectively transmits only the wavelength band of the ranging light, and selectively reflects the wavelength bands of the near-infrared laser light and the guide light. As a result, as illustrated in FIGS. 15A and 15B, in the downstream side merging mechanism 35'according to the second embodiment, the optical path formed by the distance measuring light, the optical path formed by the guide light and the near infrared laser light, and the optical path formed by the guide light and the near infrared laser light. Are staggered from the first embodiment.

Specifically, the optical member 35a'according to the second embodiment has a reflectance corresponding to the wavelength band of the ranging light of the laser light incident surface 351'and the laser light emitting surface 352' according to the second embodiment. In both cases, it is set to substantially 0% (see FIGS. 16A and 16B). With this setting, the ranging light incident on the laser beam emitting surface 352'passes through the laser beam emitting surface 352'. The ranging light that has passed through the laser beam emitting surface 352'passes through the inside of the optical member 35a while refracting, and is emitted to the outside from the laser beam incident surface 351'(see FIG. 17B).

On the other hand, as shown in FIG. 16A, the laser beam incident surface 351'according to the second embodiment selectively reflects the wavelength bands of the guide light and the near infrared laser beam. On the other hand, the laser beam emitting surface 352'according to the first embodiment transmits the wavelength bands of the guide light and the near-infrared laser light as shown in FIG. 16B.

With this setting, most of the guide light and the near-infrared laser light incident on the laser beam incident surface 351'are reflected by the laser beam incident surface 351'. A small part of the guide light and the near-infrared laser light incident on the laser light incident surface 351'is not reflected by the laser light incident surface 351'and is emitted to the outside from the laser light emitting surface 352'(. See FIG. 17A).

Similar to the optical member 35a according to the first embodiment, the optical member 35a'according to the second embodiment can suppress the propagation of the ranging light (particularly, the reflected light of the ranging light) to the guide light source 36. can. As a result, while making both the guide light and the ranging light coaxial with the near-infrared laser light, it is possible to increase the amount of light received by the ranging light receiving unit 5B and, by extension, suppress a decrease in measurement accuracy.

<< Other Embodiments >>
In the above embodiment, the near-infrared laser beam is exemplified as the processing laser beam (printing laser beam), but the wavelength band thereof is not limited to this. Further, the magnitude relationship between the wavelength band of the printing laser beam, the wavelength band of the guide light, and the wavelength band of the ranging light can be changed as appropriate.

FIG. 18 is a diagram that comprehensively illustrates the combinations of wavelengths that the near-infrared laser light, the guide light, and the ranging light can take. For example, the configuration shown at the top of FIG. 18 illustrates the wavelength setting in the first and second embodiments.

On the other hand, in the second modification from the top, for example, the wavelength of the laser light for printing is changed to 532 nm or 355 nm, and the wavelengths of the guide light and the distance measuring light are the same as those in the first and second embodiments. Corresponds to the case of setting to.

Further, in the second modification from the top, for example, the wavelength band of the guide light is changed to the low wavelength side in the near infrared region (for example, 750 nm or more and 950 nm or less), and the wavelengths of the laser light for printing and the distance measuring light are measured. Corresponds to the case where is set in the same manner as in the first and second embodiments.

Further, in the third modification from the top, for example, the wavelength of the laser light for printing is changed to 532 nm, the wavelength of the guide light is changed from the ultraviolet region to the visible light region of blue (around 400 nm), and the distance measurement is performed. This corresponds to the case where the wavelength of light is set in the same manner as in the first and second embodiments.

Further, in the fifth modification example 4 from the top, for example, the wavelength of the laser light for printing is changed to 532 nm or 355 nm, the wavelength of the guide light is changed to the near infrared region (750 nm or more), and the wavelength of the distance measurement light is changed. Corresponds to the case where is set in the same manner as in the first and second embodiments.

Further, in the modification 5 of the sixth stage from the top, for example, the wavelength of the guide light is set in the same manner as in the first and second embodiments, the wavelength of the laser light for printing is changed to 532 nm, and the distance measurement light is used. This corresponds to the case where the wavelength is changed from the ultraviolet region to the blue visible light region (around 400 nm).

Further, in each combination shown in FIG. 18, the reflectance of the distance measuring light in the optical member is set to substantially 100%, and the reflectance of the guide light and the laser light for printing is set to substantially 0%. Alternatively, by selecting whether to set the reflectance of the ranging light in the optical member to substantially 0% and the reflectance of the guide light and the laser light for printing to substantially 100%. It is possible to realize the configuration corresponding to the first and second embodiments described above.

1 Marker head 10 Housing 2 Laser light output unit 3 Laser light guide unit 31 Upstream side merging mechanism (guide light merging mechanism)
33 Z scanner (focus adjustment unit)
35 Downstream side merging mechanism (distance measuring light merging mechanism)
35a Optical member 351 Laser light incident surface 352 Laser light emitting surface 36 Guide light source (guide light emitting part)
4 Laser light scanning unit 5 Distance measuring unit 5A Distance measuring light emitting unit 5B Distance measuring light receiving unit 100 Marker controller 103 Distance measuring unit 110 Excitation light generation unit S Laser processing system W work (workpiece)

Claims (9)

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 emits the laser light.
A laser beam scanning unit that irradiates the work piece with the laser light emitted from the laser light output unit and two-dimensionally scans the surface of the work piece.
A laser processing apparatus including at least the laser beam output unit and a housing provided with the laser beam scanning unit inside.
A guide light emitting portion provided inside the housing and emitting a guide light for projecting a predetermined processing pattern onto the surface of the workpiece.
A guide light merging mechanism provided in the middle of the laser optical path from the laser light output unit to the laser light scanning unit inside the housing and merging the guide light emitted from the guide light emitting unit into the laser optical path. ,
A distance measuring light emitting unit provided inside the housing and emitting distance measuring light for measuring the distance from the laser machining apparatus to the surface of the workpiece.
A measurement provided inside the housing between the guide light merging mechanism and the laser light scanning section of the laser optical path, and the ranging light emitted from the ranging light emitting section is merged with the laser optical path. Distance light merging mechanism and
A distance measuring light receiving unit provided inside the housing and receiving the distance measuring light reflected on the surface of the workpiece and returned via the laser light scanning unit and the distance measuring light merging mechanism.
A distance measuring unit for measuring the distance from the laser processing apparatus to the surface of the workpiece based on the light receiving position of the distance measuring light in the distance measuring light receiving unit is provided.
The ranging light merging mechanism has an optical member that guides the ranging light reflected on the surface of the workpiece to the ranging light receiving unit.
The optical member selectively reflects or transmits only the wavelength band of the ranging light among the wavelength bands of the laser light, the guide light, and the ranging light, thereby measuring the ranging light. A laser processing device characterized by guiding to a distance light receiving part. In the laser processing apparatus according to claim 1,
The laser processing apparatus, wherein the optical member is coated so as to selectively reflect or transmit only the wavelength band of the ranging light. In the laser processing apparatus according to claim 1 or 2.
The optical member is a laser processing apparatus characterized in that it selectively reflects only the wavelength band of the ranging light, while transmitting the wavelength bands of the laser light and the guide light. In the laser processing apparatus according to claim 3,
On the front and back of the optical member,
The laser beam incident surface on which the laser beam and the guide light are incident, and the laser beam incident surface.
A laser beam emitting surface is provided, in which the laser beam incident from the laser beam incident surface and the guide light are emitted through the optical member.
The laser beam emitting surface selectively reflects only the wavelength band of the ranging light.
A laser processing apparatus characterized in that the laser beam incident surface is configured to transmit the wavelength band of the ranging light. In the laser processing apparatus according to claim 1 or 2.
The optical member is a laser processing apparatus characterized in that it selectively transmits only the wavelength band of the ranging light, while selectively reflecting the wavelength bands of the laser light and the guide light. In the laser processing apparatus according to any one of claims 1 to 5.
A focus adjusting unit provided inside the housing and adjusting the focal position of the laser light emitted from the laser light output unit is provided.
The distance measuring light merging mechanism is a laser processing apparatus characterized in that it is arranged between the focus adjusting unit and the laser light scanning unit in the laser optical path. In the laser processing apparatus according to claim 6,
The guide light merging mechanism is a laser processing apparatus characterized in that it is arranged between the laser light output unit and the focus adjustment unit in the laser optical path. In the laser processing apparatus according to any one of claims 1 to 7.
The wavelength bands of the ranging light and the guide light are both set in the visible light region.
A laser processing apparatus characterized in that the wavelength of the laser beam is longer than the wavelength of the ranging light and the guide light. In the laser processing apparatus according to claim 8.
The wavelength of the laser beam is set to 1064 nm, 532 nm or 355 nm.
The wavelength band of the ranging light is set to 680 nm or more and 695 nm or less.
A laser processing apparatus characterized in that the wavelength band of the guide light is set to 645 nm or more and 660 nm or less.

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