JP7203315B2 - LASER OSCILLATOR AND LASER PROCESSING DEVICE USING THE SAME - Google Patents

Description

The present invention relates to a laser oscillator and a laser processing apparatus using the same.

2. Description of the Related Art In recent years, laser processing apparatuses equipped with high-power laser oscillators have been widely used for cutting and welding metals. In particular, a laser oscillator having an output of 4 kW or more is often used for cutting a thick metal plate. On the other hand, a laser oscillator with an output of 2 kW or less is often used for thin metal plate cutting, laser marking processing, and the like. As described above, the appropriate laser output differs depending on the processing application, but since the laser processing apparatus is expensive, one laser processing apparatus is often used for multiple purposes.

However, when a laser beam with an output of 2 kW is emitted from a laser oscillator with an output of 4 kW, only half of the original power is used, which is inefficient.

Therefore, conventionally, a laser beam emitted from a high-power laser is scanned by a mirror held by a galvanomirror and introduced into different optical fibers, and the laser beam incidence time to the optical fiber is controlled to obtain a desired beam. A technology has been proposed in which a laser beam is emitted in a time-division manner with a duty ratio (see, for example, Japanese Unexamined Patent Application Publication No. 2002-100001).

Japanese Patent No. 3004625

However, in the prior art disclosed in Patent Document 1, high-precision control was required to couple the laser beam scanned by the mirror to the optical fiber. In addition, a scanner such as a galvanomirror for scanning a laser beam is expensive and large. Furthermore, this prior art does not allow the laser beams to be distributed and emitted simultaneously.

The present invention has been made in view of the above points, and its object is to provide a laser oscillator and a laser processing apparatus using the same that enable switching of the light emitting part or distribution of the laser beam with a simple configuration and operation. That's what it is.

In order to achieve the above object, a laser oscillator according to the present invention includes four laser modules each emitting first to fourth laser beams whose main polarization state is the first polarization state, and a beam combiner that combines the emitted first to fourth laser beams and outputs one or more laser beams, and a laser beam emitted from the beam combiner that has a predetermined beam diameter. and a light collecting unit for collecting light and guiding the light to a transmission fiber, wherein the beam coupler includes first to fourth light incidence sections on which the first to fourth laser beams are respectively incident. , first to fifth light reflecting members, first to third polarizing beam splitters, first polarizing members and second polarizing members, first light emitting portions and second light emitting portions , wherein the first light reflecting member reflects the first laser beam traveling in a first direction in a second direction crossing the first direction, and the second light The reflecting member reflects the first laser beam reflected by the first light reflecting member in the first direction to direct the beam toward the first polarization beam splitter, and the third light reflecting member reflects the first laser beam. reflects the third laser beam traveling in the first direction in a second direction crossing the first direction toward the second polarizing beam splitter; The member reflects the fourth laser beam traveling in the first direction in the second direction and directs it toward the second polarization beam splitter, and the third polarization beam splitter reflects the fourth laser beam traveling in the first direction to the second polarization beam splitter . The laser beam that travels in the direction 1 and is transmitted through the laser beam is directed toward the first light emitting portion, while the laser beam reflected by itself is directed toward the fifth light reflecting member. The light reflecting member directs the incident laser beam toward the second light emitting portion, and the first polarizing member passes between the second polarizing beam splitter and the third polarizing beam splitter. The second polarizing member is provided movably between a predetermined position on the optical path of the third laser beam and the fourth laser beam and a predetermined position outside the optical path, wherein the second polarizing member Between a predetermined position on the optical path of the first laser beam and the second laser beam passing between the polarizing beam splitter and the third polarizing beam splitter and a predetermined position outside the optical path is movably provided, and in a state in which the first to fourth laser beams are respectively incident on the first to fourth light incidence portions, the front By changing the positions of the first polarizing member and the second polarizing member, at least one of the laser beams emitted from the first light emitting portion and the second light emitting portion It is characterized in that the output can be changed in four stages.

According to this configuration, by a simple operation of arranging one polarizing member or another polarizing member on the optical path of a predetermined laser beam, the light emitting portion from which the laser beam LB is emitted can be switched or the laser beam can be distributed. It is possible to Also, a well-known half-wave plate or the like can be used as the first and other polarizing members.

Another laser oscillator according to the present invention comprises: four laser modules each emitting first to fourth laser beams whose main polarization state is the first polarization state; a beam combiner for combining the first to fourth laser beams and emitting one or more laser beams; and concentrating the laser beams emitted from the beam combiner so as to have a predetermined beam diameter. a light collecting unit for guiding light to a transmission fiber, wherein the beam combiner includes first to fourth light incidence portions into which the first to fourth laser beams are respectively incident; a light reflecting member, a fourth light reflecting member, first to sixth polarizing beam splitters, a first polarizing member, a third polarizing member, a fourth polarizing member, and first to third light and an emitting portion, wherein the third light reflecting member reflects the third laser beam traveling in a first direction in a second direction crossing the first direction, directed to a second polarizing beam splitter, the fourth light reflecting member reflects the fourth laser beam traveling in the first direction in the second direction to form the second polarized beam; The first polarizing beam splitter is on the optical path of the second laser beam traveling in the first direction, the second light incident portion and the fifth polarizing beam splitter. and the second polarization beam splitter splits the third laser beam reflected by the third light reflecting member and the fourth laser beam reflected by the third light reflecting member The third polarizing beam splitter, which is provided on the optical path with the beam, directs the laser beam transmitted therethrough toward the fifth polarizing beam splitter, while directing the laser beam reflected by itself to the first light beam. The fourth polarized beam splitter is on the optical path of the first laser beam traveling in the first direction, the first light incident portion and the sixth polarized beam. and the fifth polarization beam splitter, the fifth polarization beam splitter separates the second laser beam transmitted through the first polarization beam splitter and the laser beam transmitted through the third polarization beam splitter. The sixth polarizing beam splitter is provided on the optical path of each of the first laser beam transmitted through the fourth polarizing beam splitter and the laser beam transmitted through the fifth polarizing beam splitter. provided in the front The first polarizing member moves between a predetermined position on the optical path of the laser beam passing between the second polarizing beam splitter and the third polarizing beam splitter and a predetermined position outside the optical path. The third polarizing member is positioned between a predetermined position on the optical path of the laser beam passing between the third polarizing beam splitter and the fifth polarizing beam splitter and a predetermined position outside the optical path. and the fourth polarizing member is positioned at a predetermined position on the optical path of the laser beam passing between the fifth polarizing beam splitter and the sixth polarizing beam splitter and the optical path and a predetermined position outside, and the first, third, and third laser beams are incident on the first to fourth light entrance portions, respectively. By changing the position of each of the fourth polarizing members, the laser beams are emitted from the first to third light emitting portions, respectively, and the outputs of the respective laser beams can be changed. Characterized by

According to this configuration, it is possible to switch the light emitting portion from which the laser beam is emitted and to distribute the laser beam by a simple operation of arranging the polarizing members respectively on the optical paths of the plurality of predetermined laser beams. It becomes possible. Also, a well-known half-wave plate or the like can be used as a polarizing member.

Further, still another laser oscillator according to the present invention is, in addition to the configuration of the above laser oscillator, the condensing unit includes laser beams that are combined within the beam combiner and emitted out of the beam combiner. and the transmission fiber is coupled to each of the plurality of condensing units.

According to this configuration, a plurality of laser beams generated by the laser oscillator can be emitted to the outside at the same time, and one or more laser beams generated by the laser oscillator can be emitted toward different locations. .

A laser processing apparatus according to the present invention includes at least another laser oscillator, a laser beam output head attached to each of the output ends of the plurality of transmission fibers, and a controller for controlling the operation of the polarizing member. It is characterized by having

According to this configuration, it is possible to easily switch the laser beams and distribute the laser beams, so that the productivity of the laser processing process can be improved.

As described above, according to the laser oscillator of the present invention, it is possible to switch laser beams and distribute laser beams with a simple configuration and operation. Further, according to the laser processing apparatus according to the present invention, since switching of laser beams and distribution of laser beams can be performed easily, productivity of the laser processing process can be improved.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram which shows the structure of the laser processing apparatus which concerns on Embodiment 1 of this invention. FIG. 3 is a schematic diagram showing the internal configuration of a beam combiner; FIG. 10 is a schematic diagram showing the internal configuration of the beam coupler when the laser beam emitting units are switched; FIG. 4 is a schematic diagram showing the internal configuration of a beam combiner when splitting laser beams; FIG. 4 is a schematic diagram showing the internal configuration of a beam combiner when the output ratio of distributed laser beams is changed; FIG. 10 is a schematic diagram showing the internal configuration of a beam combiner when distributing laser beams according to Embodiment 2 of the present invention; FIG. 8 is another schematic diagram showing the internal configuration of the beam combiner when the output ratio of the distributed laser beams is changed; FIG. 11 is still another schematic diagram showing the internal configuration of the beam combiner when the power ratio of the distributed laser beams is further changed; It is a figure which shows the usage example of the laser processing apparatus which concerns on Embodiment 3 of this invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail based on the drawings. The following description of preferred embodiments is merely exemplary in nature and is in no way intended to limit the invention, its applicability or its uses.

(Embodiment 1)
[Configuration of laser processing device]
FIG. 1 shows the configuration of a laser processing apparatus according to this embodiment, FIG. 2 is a schematic diagram of the internal configuration of a beam combiner, and FIG. , respectively.

The laser processing apparatus 100 includes a laser oscillator 10 , laser beam emission heads 30 and 31 , transmission fibers 40 and 41 and a controller 50 . The ends of the laser oscillator 10 and the transmission fibers 40 and 41 where the laser beam LB is incident (hereinafter referred to simply as the input ends). ) are accommodated in the housing 70 . Also, the laser oscillator 10 is supplied with power from a power source (not shown) to perform laser oscillation.

The laser oscillator 10 has a plurality of laser modules 11 , a beam coupler 12 and a plurality of condensing units 20 . The laser module 11 is composed of a plurality of laser diodes or laser arrays that emit laser beams of different wavelengths. All of the first to fourth laser beams LB1 to LB4 (see FIG. 2) respectively emitted from the plurality of laser modules 11 have a main polarization state of TE polarization (first ), and the polarization ratio (intensity of TE polarized component/total light intensity) is about 95% to 97%.

The first to fourth laser beams LB1 to LB4 are combined into one or more laser beams in the beam combiner 12 (hereinafter sometimes simply referred to as combined laser beams). Further, as will be described later, when a plurality of combined laser beams are simultaneously generated by switching or distributing the optical paths of the laser beams in the beam combiner 12, the beam combiner 12 to the plurality of condensing units 20, respectively. A combined laser beam is emitted. The optical path switching operation will be described in detail later. In addition, the laser beam LB incident on the light-collecting unit 20 is collected by a light-collecting lens (not shown) disposed inside the light-collecting unit 20, and the beam diameter is reduced by a predetermined magnification before being transmitted. It enters the fiber 40 or 41 and is emitted from the laser beam emission head 30 or 31 . By configuring the laser oscillator 10 in this manner, it is possible to obtain a high-power laser processing apparatus 100 with a laser beam output exceeding several kW. Note that the laser oscillator 10 in this embodiment includes four laser modules 11 each having a laser output of 1 kW, and its maximum output is 4 kW. However, it is not particularly limited to this, and individual outputs of the laser modules 11 and the number of the laser modules 11 mounted on the laser oscillator 10 can be appropriately changed according to the required specifications of the laser processing apparatus 100 and the like.

The beam combiner 12 has first to fourth light entrance sections LI1 to LI4 and first and second light exit sections LO1 and LO2. The first to fourth light entrance sections LI1 to LI4 are provided on the same surface of the beam combiner 12, and the first and second light exit sections LO1 and LO2 are provided on separate surfaces of the beam combiner 12. ing. 2 and 3, the beam combiner 12 includes first to fifth mirrors ( first to fifth light reflecting members) M1 to M5 and first to third polarized beams. It has splitters PBS1 to PBS3, first and second half- wave plates HWP1 ( first polarizing member), HWP2 ( second polarizing member), and first and second beam dampers DP1, DP2. . Of these, the first and second half- wave plates HWP1 and HWP2 are configured to be movable within the beam combiner 12. As shown in FIG. The first and second half- wave plates HWP1 and HWP2 are polarizing members that change the polarization state of the incident laser beam and emit it. The illustration and description of the actuators for moving the first and second half- wave plates HWP1 and HWP2 are omitted.

The condenser unit 20 has a condenser lens (not shown) inside, and the condenser lens has a spot diameter smaller than the core diameter of each transmission fiber at the incident end of the transmission fiber 40 or 41. The laser beam LB is condensed so that The light collecting unit 20 also has a connector (not shown) to which the incident end of the transmission fiber 40 or 41 is connected. In addition, in the light collecting unit 20, according to the number of laser beams that are combined in the beam combiner 12 and emitted outside the beam combiner 12, or according to the number of light emitting portions of the beam combiner 12, , a condenser lens is provided on the optical path of the laser beam emitted from the beam combiner 12 . Other optical components such as a collimator lens for beam shaping may be arranged on the optical path of each laser beam.

In the following description, the direction in which the laser beam LB travels toward the condenser lens unit 20 is the X direction, the arrangement direction of the plurality of laser modules 11 is the Y direction, and the direction orthogonal to the X and Y directions is the Z direction. I may call

The transmission fiber 40 or 41 transmits the laser beam LB received from the focusing unit 20 to the laser beam emission head 30 or 31 . Although not shown, the transmission fibers 40 and 41 are provided with a clad having a lower refractive index than the core around the core, and the surface of the clad is covered with a film.

The laser beam emitting head 30 or 31 irradiates the laser beam LB transmitted by the transmission fiber 40 or 41 toward a work (not shown).

The control unit 50 controls laser oscillation of the laser oscillator 10 . Specifically, laser oscillation control of each laser module 11 is performed by supplying a control signal such as an output voltage and ON time to a power supply (not shown) connected to the laser oscillator 10 . It is also possible to individually control laser oscillation for each laser module 11 . For example, each laser module 11 may have a different laser oscillation output, ON time, or the like. The control unit 50 also controls the operation of the first and second half- wave plates HWP1 and HWP2 arranged in the beam coupler 12 and other optical components, specifically, the first and second half-wave plates HWP1 and HWP2. It controls the operation of actuators (not shown) connected to the /2 wave plates HWP1, HWP2, and so on. Note that the controller 50 may control the operation of a manipulator (not shown) to which the laser beam emitting head 30 is attached.

[Switching operation of the laser beam emitting part]
As shown in FIGS. 2 and 3, in the laser oscillator 10 according to the present embodiment, the laser beam LB emitted from the beam coupler 12 can be emitted from either the first or second light emitting portion LO1 or LO2. It is possible to switch. Thereby, it is possible to switch between emitting the laser beam LB from the laser beam emitting head 30 and emitting from the laser beam emitting head 31 . This will be described in detail below.

First, consider the case where the laser beam LB is emitted from the first light emitting portion LO1. As shown in FIG. 2, the first to fourth laser beams LB1 to LB4 that enter the beam combiner 12 from the first to fourth light incidence portions LI1 to LI4 are directed in the same direction, in this case, the Z direction. proceed to Among them, the first laser beam LB1 is reflected by the first mirror M1, directed to the second mirror M2, changed again by the second mirror M2, and travels in the Z direction again. The second laser beam LB2 passes through the vicinity of the second mirror M2, travels straight in the Z direction, and enters the first polarization beam splitter PBS1 together with the first laser beam LB1. Immediately before entering the first polarization beam splitter PBS1, the first laser beam LB1 travels in parallel with the optical path of the second laser beam LB2 with a predetermined interval.

Among the first and second laser beams LB1 and LB2 incident on the first polarization beam splitter PBS1, the component other than the TEE polarization component, that is, the TM polarization (second polarization state) component is the first polarization. It is reflected by the beam splitter PBS1, enters the first beam damper DP1, and is absorbed. As a result, the first and second laser beams LB1 and LB2 that pass through the first polarization beam splitter PBS1 have only TE polarization components.

On the other hand, the third laser beam LB3 is reflected by the third mirror M3 and travels in the Y direction toward the second polarization beam splitter PBS2. Further, the fourth laser beam LB4 is reflected by the fourth mirror M4, travels in the Y direction parallel to the optical path of the third laser beam LB3 with a predetermined interval, and reaches the third mirror M3. , toward the second polarizing beam splitter PBS2.

Of the third and fourth laser beams LB3 and LB4 incident on the second polarizing beam splitter PBS2, the TM polarized component is reflected by the second polarizing beam splitter PBS2 and enters the second beam damper DP2, be absorbed. As a result, the third and fourth laser beams LB3 and LB4 that pass through the second polarization beam splitter PBS2 have only TE polarized components.

The first and second laser beams LB1 and LB2 transmitted through the first polarization beam splitter PBS1 enter the third polarization beam splitter PBS3. The first and second laser beams LB1 and LB2 pass through the polarizing beam splitter PBS and proceed directly to the first light emitting section LO1.

On the other hand, if the first half-wave plate HWP1 is arranged on the optical paths of the third and fourth laser beams LB3 and LB4 that have passed through the second polarization beam splitter PBS2, the third and fourth The polarization states of the laser beams LB3 and LB4 are changed. That is, the TE polarization is changed to another polarization state, in this case, the TM polarization state. The third and fourth laser beams LB3 and LB4 changed to TM polarized light are reflected by the third polarizing beam splitter PBS3. Here, the third polarization beam splitter PBS3 is arranged so as to change the direction of travel of the third and fourth laser beams LB3 and LB4 from the Y direction to the Z direction. That is, they are arranged so as to form an angle of 45° with the direction of travel of the third and fourth laser beams LB3 and LB4. Also, the third polarizing beam splitter PBS3 is arranged to form an angle of 45° with the traveling directions of the first and second laser beams LB1 and LB2. Therefore, the third and fourth laser beams LB3 and LB4 reflected by the third polarizing beam splitter PBS3 travel in the Z direction and head straight toward the first light emitting portion LO1.

Here, one of the first and second laser beams LB1 and LB2 after passing through the third polarization beam splitter PBS3 and the third and second laser beams after being reflected by the third polarization beam splitter PBS3 Each part in the beam combiner 12 is arranged so that one of the four laser beams LB3 and LB4 has the same optical axis. Further, the other of the first and second laser beams LB1 and LB2 after passing through the third polarization beam splitter PBS3 and the third and fourth laser beams after being reflected by the third polarization beam splitter PBS3 Each part in the beam coupler 12 is arranged so that the other of the beams LB3 and LB4 has the same optical axis. In this embodiment, as shown in FIG. 2, the first laser beam LB1 and the fourth laser beam LB4 have the same optical axis from the third polarizing beam splitter PBS3 to the first light emitting part LO1. and so that the second laser beam LB2 and the third laser beam LB3 have the same optical axis, the first to fourth light incident portions LI1 to LI4 and the first to fourth mirrors The arrangement of M1 to M4 and the third polarizing beam splitter PBS3 is determined.

By causing the first to fourth laser beams LB1 to LB4 to enter the third polarization beam splitter PBS3 in this way, the first to fourth laser beams LB1 to LB4 are combined into one laser beam LB. The light is emitted from the first light emitting portion LO1. Also, in this case, in the laser processing apparatus 100 shown in FIG. 1, the laser beam LB emitted from the condensing unit 20 passes through the transmission fiber 40 and is emitted from the laser beam emission head 30 .

Next, consider the case where the laser beam LB is emitted from the second light emitting portion LO2. As shown in FIG. 3, first to fourth light incident portions LI1 to LI4, first to fourth mirrors M1 to M4, first to third polarization beam splitters PBS1 to PBS3, and first and second beam splitters PBS1 to PBS3. The arrangement of the beam dampers DP1 and DP2 is the same as that shown in FIG. Also, the optical paths of the first and second laser beams LB1 and LB2 immediately after passing through the first polarization beam splitter PBS1 and the third and fourth laser beams immediately after passing through the second polarization beam splitter PBS2 are shown. The optical paths of LB3 and LB4 are also the same as shown in FIG. On the other hand, as shown in FIG. 3, the first half-wave plate HWP1 is retracted outside the optical paths of the third and fourth laser beams LB3 and LB4, while the second half-wave plate HWP2 is moved. and placed on the optical paths of the first and second laser beams LB1 and LB2 that pass through the first polarizing beam splitter PBS1 and enter the third polarizing beam splitter PBS3. As a result, the third and fourth laser beams LB3 and LB4 pass through the third polarization beam splitter PBS3 and travel straight in the Y direction, while being converted into TM polarized light by the second half-wave plate HWP2. The first and second laser beams LB1 and LB2 are reflected by the third polarizing beam splitter PBS3, change their traveling direction from the Z direction to the Y direction, and travel straight.

As shown in FIG. 3, the first laser beam LB1 reflected by the third polarization beam splitter PBS3 and the fourth laser beam LB4 transmitted through the third polarization beam splitter PBS3 have the same optical axis. Also, the second laser beam LB2 reflected by the third polarization beam splitter PBS3 and the third laser beam LB3 transmitted through the fourth polarization beam splitter PBS4 have the same optical axis . Arrangements of the first to fourth light incident portions LI1 to LI4, the first to fourth mirrors M1 to M4, and the third polarization beam splitter PBS3 are determined.

The first to fourth laser beams LB1 to LB4 thus combined by the third polarization beam splitter PBS3 are combined into one laser beam LB and reflected by the fifth mirror M5. The fifth mirror M5 corresponds to a predetermined distance in the Y direction from the third polarizing beam splitter PBS3, in this case, the distance in the Y direction between the first light exit LO1 and the second light exit LO2. are provided at intervals. The laser beam LB reflected by the fifth mirror M5 is emitted from the second light emitting portion LO2. Also, in this case, in the laser processing apparatus 100 shown in FIG. 1 , the laser beam LB emitted from the condensing unit 20 passes through the transmission fiber 41 and is emitted from the laser beam emission head 31 .

[Regarding laser beam distribution and output ratio change operation]
FIG. 4 is a schematic diagram of the internal configuration of the beam combiner when splitting the laser beams according to this embodiment, and FIG. 5 is a schematic diagram of the internal configuration of the beam combiner when the output ratio of the split laser beams is changed. Figures are shown respectively. The beam combiner 12 shown in FIGS. 4 and 5 is the same as the beam combiner 12 shown in FIGS. 2 and 3, and the internal structure is also the same as that shown in FIGS.

By disposing the first and second half- wave plates HWP1 and HWP2, particularly by moving the second half-wave plate HWP2 to a predetermined position, the first and second light emitting portions LO1 and LO2 Laser beams can be emitted from both, and the output ratio can be changed. This will be described in detail below.

First, consider the case where laser beams LBA and LBB having the same output are emitted from the first and second light emitting portions LO1 and LO2, respectively. As shown in FIG. 4, the optical paths of the first and second laser beams LB1 and LB2 immediately after passing through the first polarizing beam splitter PBS1 and the third and second laser beams LB1 and LB2 immediately after passing through the second polarizing beam splitter PBS2. The optical paths of the fourth laser beams LB3 and LB4 are the same as shown in FIGS.

On the other hand, as shown in FIG. 4, the first half-wave plate HWP1 passes through the second polarization beam splitter PBS2 and enters the third polarization beam splitter PBS3 . The second half-wave plate HWP2, which is placed on the optical paths of the laser beams LB3 and LB4, passes through the first polarization beam splitter PBS1 and enters the third polarization beam splitter PBS3 . 1 and 2 on the optical paths of the first and second laser beams LB1 and LB2. Since the third and fourth laser beams LB3 and LB4 are changed to TM-polarized light by the first half-wave plate HWP1, they are reflected by the third polarizing beam splitter PBS3, travel straight in the Z direction, and reach the first toward the light exit portion LO1. Also, since the first and second laser beams LB1 and LB2 are also changed to TM-polarized light by the second half-wave plate HWP2, they are reflected by the third polarizing beam splitter PBS3, travel straight in the Y direction, Head to the fifth mirror M5. The traveling directions of the first and second laser beams LB1 and LB2 reflected by the fifth mirror M5 are changed from the Y direction to the Z direction and head toward the second light emitting portion LO2. In the third polarizing beam splitter PBS3, the reflecting surface that reflects the first and second laser beams LB1 and LB2 and the reflecting surface that reflects the third and fourth laser beams LB3 and LB4 are mutually They are facing surfaces.

As a result, the laser beam LBA, which is the combination of the third laser beam LB3 and the fourth laser beam LB4, is emitted from the first light emitting unit LO1, and the first laser beam LB1 and the second laser beam LB2 are combined. The laser beams LBB thus formed are emitted from the second light emitting portion LO2. In this embodiment, since the first to fourth laser beams LB1 to LB4 have the same laser output (1 kW), the laser beam LBA emitted from the first light emitting portion LO1 and the second light emitting portion The power ratio with the laser beam LBB emitted from LO2 is 1:1. Further, in this case, in the laser processing apparatus 100 shown in FIG. 1, the two laser beams LBA and LBB emitted from the light condensing unit 20 pass through the transmission fibers 40 and 41, respectively, from the laser beam emission heads 30 and 31. Each emits the same output.

Next, consider the case of changing the output ratio between the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam LBB emitted from the second light emitting portion LO2. As shown in FIG. 5, the optical paths of the first and second laser beams LB1 and LB2 immediately after passing through the first polarizing beam splitter PBS1 and the third and second laser beams LB1 and LB2 immediately after passing through the second polarizing beam splitter PBS2. The optical paths of the fourth laser beams LB3 and LB4 are the same as shown in FIG.

Here, as in FIG. 4, the first half-wave plate HWP1 passes through the second polarization beam splitter PBS2 and enters the third polarization beam splitter PBS3 . While placed on the optical paths of the laser beams LB3 and LB4, as shown in FIG. 5, the second half-wave plate HWP2 passes through the first polarization beam splitter PBS1 and passes through the third polarization beam splitter PBS3. is placed on the optical path of the first laser beam LB1 until it is incident on the . Since the third and fourth laser beams LB3 and LB4 are changed to TM-polarized light by the first half-wave plate HWP1, they are reflected by the third polarizing beam splitter PBS3, travel straight in the Z direction, and reach the first toward the light exit portion LO1. Also, the first laser beam LB1 is also changed to TM-polarized light by the second half-wave plate HWP2, so that it is reflected by the third polarizing beam splitter PBS3, travels straight in the Y direction, and passes through the fifth mirror M5. head to The traveling directions of the first and second laser beams LB1 and LB2 reflected by the fifth mirror M5 are changed from the Y direction to the Z direction and head toward the second light emitting portion LO2.

On the other hand, since the second laser beam LB2 does not pass through the second half-wave plate HWP2, it is incident on the third polarization beam splitter PBS3 as TE polarized light. Therefore, the second laser beam LB2 passes through the third polarization beam splitter PBS3 as it is, and is combined with the third and fourth laser beams LB3 and LB4. The second laser beam LB2 and the third laser beam LB3 travel on the same optical axis from the third polarization beam splitter PBS3 to the first light emitting portion LO1.

As a result, the laser beam LBA obtained by combining the second to fourth laser beams LB2 to LB4 is emitted from the first light emitting portion LO1, and the first laser beam LB1 is emitted from the second light emitting portion LO2 as the laser beam LBB. emitted respectively. In this embodiment, since the first to fourth laser beams LB1 to LB4 have the same laser output (1 kW), the laser beam LBA emitted from the first light emitting portion LO1 and the second light emitting portion The power ratio with the laser beam LBB emitted from LO2 is 3:1. That is, compared to the case shown in FIG. 4, the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam LBB emitted from the second light emitting portion LO2 have different outputs, that is, the above output distributed in proportion.

Further, in this case, in the laser processing apparatus 100 shown in FIG. 1, the two laser beams LBA and LBB emitted from the light condensing unit 20 pass through the transmission fibers 40 and 41, respectively, from the laser beam emission heads 30 and 31. It is emitted with an output ratio of 3:1.

Note that the second half-wave plate HWP2 is placed on the optical path of the second laser beam LB2 that passes through the first polarizing beam splitter PBS1 and enters the third polarizing beam splitter PBS3. Similarly, the laser beam LBA, which is a combination of the first, third, and fourth laser beams LB1, LB3, and LB4, is emitted from the first light emitting unit LO1, and the second laser beam LB2 is emitted as the laser beam LBB. 2, and the output ratio between the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam LBB emitted from the second light emitting portion LO2 is 3:1. . Also, the first laser beam LB1 and the fourth laser beam LB4 travel on the same optical axis and are emitted from the first light emitting portion LO1 as part of the laser beam LBA.

[Effects, etc.]
As described above, the laser oscillator 10 according to the present embodiment includes a plurality of laser modules 11 each emitting a laser beam whose main polarization state is TE polarization (first polarization state), and laser beams emitted from these laser modules 11. a beam combiner 12 that combines the first to fourth laser beams LB1 to LB4 and outputs one or more laser beams LB; and a condensing unit 20 for condensing light to a beam diameter and guiding the light to transmission fibers 40 and/or 41 .

The beam combiner 12 has first and second light emitting sections LO1 and LO2 from which the laser beam LB combined in the beam combiner 12 is emitted, and converts the incident laser beam from TE polarized light to TM polarized light (second polarized light). 2 polarization states), and a third half- wave plate HWP1, HWP2 that transmits a TE-polarized laser beam and reflects a TM-polarized laser beam . and a polarizing beam splitter PBS3.

The first half-wave plate HWP1 ( first polarizing member) is positioned between a predetermined position on the optical path of at least one of the third and fourth laser beams LB3 and LB4 and a predetermined position outside the optical path. A second half-wave plate HWP2 ( a second polarizing member) is provided at a predetermined position on the optical path of at least one of the first and second laser beams LB1 and LB2 and outside the optical path. is provided so as to be movable between a predetermined position of

Among the first to fourth laser beams LB1 to LB4, the first and second laser beams LB1 and LB2 travel in the Z direction (first direction) and enter the third polarization beam splitter PBS3. , third and fourth laser beams LB3 and LB4 travel in the Y direction (second direction) crossing the Z direction and enter the third polarization beam splitter PBS3.

A second half-wave plate HWP2 is disposed at a predetermined position on the optical path of at least one of the first and second laser beams LB1 and LB2 traveling in the Z direction, or By disposing the first half-wave plate HWP1 at a predetermined position on the optical path of at least one of the traveling third and fourth laser beams LB3 and LB4, the first half-wave plate HWP1 The laser beam transmitted through the wave plate HWP1 or the second half-wave plate HWP2 is changed to the TM polarization state. In this case, by the third polarization beam splitter PBS3, if the direction different from the traveling direction up to that time, that is, the traveling direction until being incident on the third polarization beam splitter PBS3 is the Y direction, If the direction of travel before entering the polarizing beam splitter PBS3 is the Z direction, it is reflected in the Y direction. On the other hand, the laser beam that does not pass through the first half-wave plate HWP1 or the second half-wave plate HWP2 passes through the third polarization beam splitter PBS3.

By configuring the laser oscillator 10 in this way, the first 1/2 HWP1 or the second 1/2 wavelength plate HWP2, which is the first polarizing member, can be arranged on the optical path of the laser beam or outside the optical path. With a simple operation of retreating, the direction of travel of the first to fourth laser beams LB1 to LB4 until they are incident on the third polarization beam splitter PBS3 and the direction of travel after the third polarization beam splitter PBS3. The number of laser beams with different directions can be adjusted. That is, it is possible to change the direction in which the first to fourth laser beams LB1 to LB4 are directed, or to change the number ratio of the laser beams directed in different directions. As a result, of the first and second light emitting portions LO1 and LO2, the light emitting portion from which the laser beam LB is emitted can be switched, or the laser beam LBA can be emitted from the first and second light emitting portions LO1 and LO2 at the same time. , LBB can be emitted. In addition, since switching and distribution of laser beams can be performed within the laser oscillator 10 without using an external optical system as disclosed in Patent Document 1, an increase in the size of the laser oscillator 10 can be suppressed. Also, a well-known half-wave plate can be used as the polarizing member, and the laser oscillator 10 can be configured easily. Furthermore, a simple mechanism can be used for moving the first and second half- wave plates HWP1 and HWP2.

Further, by inserting the first half-wave plate HWP1 or the second half-wave plate HWP2 in the optical path of the laser beams incident on the third polarization beam splitter PBS3 from different directions, the third It is possible to control whether the laser beam incident on the polarizing beam splitter PBS3 is reflected or transmitted. As a result, the laser beam reflected by the third polarization beam splitter PBS3 and the laser beam transmitted through the third polarization beam splitter PBS3 are combined by the third polarization beam splitter PBS3 so as to have the same optical axis. A laser beam LB is emitted from at least one of the first and second light emitting portions LO1 and LO2.

The beam quality of the combined laser beam LB in the beam combiner 12 can be improved by combining the two laser beams with the same optical axis by the third polarization beam splitter PBS3. As described above, the first laser beam LB1 travels parallel to the optical path of the second laser beam LB2 with a predetermined interval, and the third laser beam LB3 travels along the path of the fourth laser beam LB2. It travels parallel to the optical path of LB4 with a predetermined interval. Therefore, when the first to fourth laser beams LB1 to LB4 are emitted from the same light emitting portion by simply changing the direction of travel by using a mirror or the like, the laser beams LB are emitted from the first to fourth laser beams LB1 to LB4 which are spaced apart from each other by optical axes. It becomes a combined beam of the fourth laser beams LB1 to LB4. Therefore, the diameter of the laser beam LB is greatly expanded, and the shape of the spot is far from circular.

If a workpiece is processed with such a laser beam LB, for example, the width of the cut portion may become larger than a desired value, or the desired drilling process may not be possible. Further, if the spot diameter of the laser beam LB is made closer to a circle, the number of optical parts such as lenses increases, and the laser oscillator 10 may become expensive.

On the other hand, according to the present embodiment, the laser beam LB is generated with the optical axes of at least two laser beams being the same. The beam quality of LB can be improved. As a result, processing quality can be improved in the laser processing apparatus 100 using this laser oscillator 10 .

The laser beam transmitted through the third polarization beam splitter PBS3 and the third mirror M5 ( fifth light reflecting member) provided at a predetermined distance from the third polarization beam splitter PBS3 in the Y direction are provided . At least one of the laser beams reflected by the polarizing beam splitter PBS3 has its optical path bent, and the laser beam that does not enter another light emitting portion, for example, the fifth mirror M5 is emitted from the first light emitting portion LO1. In this case, the laser beam incident on the fifth mirror M5 may be reflected and emitted from the second light emitting portion LO2.

By doing so, the light emitting portion for emitting the laser beam LB can be switched with a simple configuration, and the laser beams LBA and LBB can be emitted from the first and second light emitting portions LO1 and LO2, respectively. It can also be emitted.

Alternatively, the number of the second half-wave plate HWP2 arranged on the optical path of the first and second laser beams LB1 and LB2 traveling in the Z direction may be changed, or the number of laser beams traveling in the Y direction may be changed. By changing the number of the first half-wave plate HWP1 arranged on the optical path of the third and fourth laser beams LB3 and LB4, The output ratio of the emitted laser beams LBA and LBB can be changed.

The arrangement is not limited to that shown in FIGS. 4 and 5, and by configuring the laser oscillator 10 in this way, the output of the laser beams LBA and LBB emitted from the first and second light emitting portions LO1 and LO2, respectively, can be changed. You can change the ratio. For example, in the configuration shown in FIG. 2, the third laser beam LB3 passes through the first half-wave plate HWP1, passes through the second polarization beam splitter PBS2, and enters the third polarization beam splitter PBS3. When arranged either on the optical path or on the optical path of the fourth laser beam LB4, the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam emitted from the second light emitting portion LO2 The output ratio with the LBB is 3:1 as in the configuration shown in FIG. Also, the beam quality of the laser beam LBA is the same as in the case shown in FIG.

Further, in the configuration shown in FIG. 3, the first laser beam LB1 passes through the second half-wave plate HWP2, passes through the first polarization beam splitter PBS1, and enters the third polarization beam splitter PBS3. When arranged either on the optical path or on the optical path of the second laser beam LB2, the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam emitted from the second light emitting portion LO2 The output ratio with LBB is 1:3. The beam quality of the laser beam LBB emitted from the second light emitting portion LO2 is equivalent to the beam quality of the laser beam LB emitted from the first light emitting portion LO1 shown in FIG.

A second half-wave plate HWP2 is placed at a predetermined position on the optical path of the first and second laser beams LB1 and LB2 traveling in the Z direction among the first to fourth laser beams LB1 to LB4. The first half-wave plate HWP1 is also arranged at a predetermined position on the optical path of the third and fourth LB3 and LB4 which are arranged and advance in the Y direction . Laser beams LBA and LBB can be emitted from the light emitting portions LO1 and LO2, respectively. In this case, of the first and second laser beams LB1 and LB2 traveling in the Z direction, either the number of the second half-wave plate HWP2 arranged on the optical path is changed, or the number of laser beams traveling in the Y direction is changed. By changing the number of the first half-wave plate HWP1 arranged on the optical path of the third and fourth laser beams LB3 and LB4, The output ratio of the emitted laser beams LBA and LBB can be changed.

For example, in the configuration shown in FIG. 5, the third and fourth laser beams pass through the first half-wave plate HWP1 through the second polarization beam splitter PBS2 and enter the third polarization beam splitter PBS3. When the beams LB3 and LB4 are retracted from the optical path, the output ratio between the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam LBB emitted from the second light emitting portion LO2 is 1:3. Become. However, in this case, in the laser beam LBB emitted from the second light emitting portion LO2, the optical axes of the first, third and fourth laser beams LB1, LB3 and LB4 are spaced apart from each other by a predetermined distance. Therefore, the beam quality of the laser beam LBB is lower than that of the laser beam LBA emitted from the first light emitting portion LO1 shown in FIG.

Note that the number of the light incident portions and the number of light emitting portions can be appropriately changed according to the specifications of the laser oscillator 10 and the like. Accordingly, the output ratio of the laser beams can also be changed as appropriate.

A plurality of light collecting units 20 are provided according to the number of laser beams that are combined in the beam combiner 12 and emitted outside the beam combiner 12, and each of the light collecting units 20 has a transmission fiber. is connected. In this embodiment, transmission fibers 40 and 41 are connected to two condensing units 20, respectively.

With such a configuration, a plurality of laser beams generated by the laser oscillator 10 can be emitted to the outside at the same time, and one or more laser beams generated by the laser oscillator 10 can be directed to different locations. can be emitted.

Note that components other than the TE polarized components of the first to fourth laser beams LB1 to LB4 are separated by using the first and second polarizing beam splitters PBS1 and PBS2 before being incident on the third polarizing beam splitter PBS3. , it is possible to prevent an unintended laser beam from being emitted from the first light emitting portion LO1 and/or the second light emitting portion LO2. Moreover, the output of the laser beam LB or LBA, LBB emitted from the first light emitting portion LO1 and/or the second light emitting portion LO2 can be accurately defined.

(Embodiment 2)
FIG. 6A is a schematic diagram of the internal configuration of the beam combiner when distributing the laser beams according to the present embodiment, and FIG. 6B is the internal configuration of the beam combiner when the output ratio of the distributed laser beams is changed. , and FIG. 6C shows a schematic diagram of the internal configuration of the beam combiner when the output ratio of the distributed laser beams is further changed.

The configuration shown in this embodiment and the configuration shown in Embodiment 1 are different in the following points. First, in the configuration shown in this embodiment, the number of light emitting portions is increased to three ( first to third light emitting portions LO1 to LO3). Also, the first, second and fifth mirrors M1, M2, M5 and the second half-wave plate HWP2 are omitted, and instead the fourth to sixth polarizing beam splitters PBS4 to PBS6 and the third and a fourth half- wave plate HWP3, HWP4 (third and fourth polarizing members) and a beam damper 3 are added. Note that the first to fourth light incidence portions LI1 to LI4, the third and fourth mirrors M3 and M4, the first to third polarization beam splitters PBS1 to PBS3, and the first and second beam dampers DP1 and DP2 The arrangement is the same as the arrangement shown in the first embodiment.

According to this embodiment, the first to fourth laser beams LB1 to LB4 incident from the first to fourth light incident portions LI1 to LI4 are combined in the beam combiner 12 to form the first to third laser beams LB1 to LB4. can be emitted from any one or each of the light emitting portions LO1 to LO3. This will be described in detail below.

As shown in FIG. 6A, the optical path of the second laser beam LB2 immediately after passing through the first polarizing beam splitter PBS1 and the third and fourth laser beams immediately after passing through the second polarizing beam splitter PBS2. The optical paths of LB3 and LB4 are the same as shown in FIGS.

On the other hand, as shown in FIG. 6A, the first half-wave plate HWP1 passes through the second polarization beam splitter PBS2 and enters the third polarization beam splitter PBS3 . It is arranged on the optical path of the laser beams LB3 and LB4. Since the third and fourth laser beams LB3 and LB4 are changed to TM-polarized light by the first half-wave plate HWP1, they are reflected by the third polarizing beam splitter PBS3, travel straight in the Z direction, and reach the first toward the light exit portion LO1. On the other hand, the second laser beam LB2, which remains TE-polarized, passes through the first and fifth polarization beam splitters PBS1 and PBS5 as they are, and travels toward the second light emitting portion LO2. Similarly, the first laser beam LB1, which is still TE-polarized, is transmitted through the fourth and sixth polarizing beam splitters PBS4 and PBS6 as it is, and travels to the third light emitting portion LO3. The TM polarization components contained in the first and second laser beams LB1 and LB2 are reflected by the first and fourth polarization beam splitters PBS1 and PBS4, respectively, and are sent to the first and third beam dampers DP1 and DP3. absorbed respectively.

As a result, the laser beam LBA obtained by combining the third laser beam LB3 and the fourth laser beam LB4 is emitted from the first light emitting portion LO1, and the second laser beam LB2 is emitted as the laser beam LBB from the first light emitting portion LO1. From the portion LO1, the first laser beam LB1 is emitted from the third light emitting portion LO3 as the laser beam LBC. In this embodiment, since the first to fourth laser beams LB1 to LB4 have the same laser output (1 kW), the output ratio of the laser beam LBA, the laser beam LBB, and the laser beam LBC is 2:1:1. is. In this case, in the laser processing apparatus 100 shown in FIG. 1, the three laser beams LBA, LBB, and LBC emitted from the light condensing unit 20 pass through the transmission fibers 40, 41 and a transmission fiber (not shown), respectively. The beams are emitted from the beam emitting heads 30, 31 and the laser beam emitting head (not shown) at the above output ratio.

Further, as shown in FIG. 6B, the first half-wave plate HWP1 passes through the second polarization beam splitter PBS2 and passes through the fourth laser beam LB4 until it enters the third polarization beam splitter PBS3. and the third laser beam LB3 until the third half-wave plate HWP3 passes through the third polarization beam splitter PBS3 and enters the fifth polarization beam splitter PBS5. is placed on the optical path of Since the fourth laser beam LB4 is changed to TM polarized light by the first half-wave plate HWP1, the fourth laser beam LB4 is reflected by the third polarizing beam splitter PBS3, travels straight in the Z direction, and reaches the first light emitting portion LO1. head to On the other hand, the third laser beam LB3, after passing through the third polarizing beam splitter PBS3, is changed into TM-polarized light by the third half-wave plate HWP3, so that it is reflected by the fifth polarizing beam splitter PBS5. to move straight in the Z direction toward the second light emitting portion LO2.

As shown in FIG. 6A, the second laser beam LB2 is still TE-polarized and passes through the first and fifth polarizing beam splitters PBS1 and PBS5 as they are, and travels toward the second light emitting portion LO2. Further, the first laser beam LB1, which is still TE polarized, is transmitted through the fourth and sixth polarizing beam splitters PBS4 and PBS6 as it is, and travels to the third light emitting portion LO3. The TM polarized light components contained in the first and second laser beams LB1 and LB2 are reflected by the first and fourth polarizing beam splitters PBS1 and PBS4, respectively, and are reflected by the first and third beam dampers DP1 and DP3. absorbed respectively.

As a result, the fourth laser beam LB4 is emitted from the first light emitting portion LO1 as the laser beam LBA, and the laser beam LBB obtained by combining the second laser beam LB2 and the third laser beam LB3 is the second light emission. From the portion LO2, the first laser beam LB1 is emitted from the third light emitting portion LO3 as the laser beam LBC. In this case, the power ratio of the laser beam LBA, the laser beam LBB, and the laser beam LBC is 1:2:1. In this case, in the laser processing apparatus 100 shown in FIG. 1, the three laser beams LBA, LBB, and LBC emitted from the light condensing unit 20 pass through the transmission fibers 40, 41 and a transmission fiber (not shown), respectively. The beams are emitted from the beam emitting heads 30, 31 and the laser beam emitting head (not shown) at the above output ratio.

Also, as shown in FIG. 6C, the first half-wave plate HWP1 passes through the second polarization beam splitter PBS2 and passes through the third laser beam LB3 until it enters the third polarization beam splitter PBS3. and the fourth half-wave plate HWP4 passes through the fifth polarizing beam splitter PBS5 and enters the sixth polarizing beam splitter PBS6 . is placed on the optical path of Since the third laser beam LB3 is changed to TM polarized light by the first half-wave plate HWP1, the third laser beam LB3 is reflected by the third polarizing beam splitter PBS3, travels straight in the Z direction, and reaches the first light emitting portion LO1. head to On the other hand, the fourth laser beam LB4 passes through the third and fifth polarizing beam splitters PBS3 and PBS5, and is then converted into TM polarized light by the fourth half-wave plate HWP4 . After being reflected by the splitter PBS6, the light travels straight in the Z direction toward the third light emitting portion LO3.

As shown in FIG. 6A, the second laser beam LB2 is still TE-polarized and passes through the first and fifth polarizing beam splitters PBS1 and PBS5 as they are, and travels toward the second light emitting portion LO2. Further, the first laser beam LB1, which is still TE polarized, is transmitted through the fourth and sixth polarizing beam splitters PBS4 and PBS6 as it is, and travels to the third light emitting portion LO3. The TM polarization components contained in the first and second laser beams LB1 and LB2 are reflected by the first and fourth polarization beam splitters PBS1 and PBS4, respectively, and are reflected by the first and third beam dampers DP1 and DP1, respectively. Each is absorbed by DP3.

As a result, the third laser beam LB3 is emitted from the first light emitting portion LO1 as the laser beam LBA, the second laser beam LB2 is emitted from the second light emitting portion LO2 as the laser beam LBB, and is emitted from the first laser beam LB1. The laser beams LBC combined with the fourth laser beam LB4 are emitted from the third light emitting portion LO3. In this case, the output ratio of the laser beam LBA, the laser beam LBB, and the laser beam LBC is 1:1:2. In this case, in the laser processing apparatus 100 shown in FIG. 1, the three laser beams LBA, LBB, and LBC emitted from the light condensing unit 20 pass through the transmission fibers 40, 41 and a transmission fiber (not shown), respectively. The beams are emitted from the beam emitting heads 30, 31 and the laser beam emitting head (not shown) at the above output ratio.

According to the laser oscillator 10 according to this embodiment, the same effects as those of the first embodiment can be obtained. Also, the laser beams LBA to LBC can be simultaneously emitted from the first to third light emitting portions LO1 to LO3, respectively. Also, the output ratio of the laser beams LBA to LBC can be changed.

Note that the second half-wave plate HWP2 shown in Embodiment 1 is made movable with respect to the optical path between the first polarizing beam splitter PBS1 and the fifth polarizing beam splitter PBS5 in the second laser beam LB2. You may make it provide. For example, in the configuration shown in FIG. 6A, by placing the second half-wave plate HWP2 between the first polarizing beam splitter PBS1 and the fifth polarizing beam splitter PBS5, the second laser beam LB2 is The laser beam LBC, which is reflected by the fifth and sixth polarizing beam splitters PBS5 and PBS6 and directed toward the third light emitting portion LO3, is the third light beam LBC, which is the combination of the first and second laser beams LB1 and LB2. It is emitted from the emission part LO3. In this case, the output ratio between the laser beam LBA emitted from the first light emitting portion LO1 and the laser beam LBC emitted from the third light emitting portion LO3 is 1:1, and the maximum output of each is 2 kW. .

Further, by retracting the first half-wave plate HWP1 out of the optical paths of the third and fourth laser beams LB3 and LB4, the third and fourth laser beams LB3 and LB4 pass through the third polarizing beam splitter. It passes through PBS3 and goes straight in the Y direction. At this time, at the same time, the third and fourth laser beams LB3 and LB4 pass through the third half-wave plate HWP3, pass through the third polarization beam splitter PBS3, and enter the fifth polarization beam splitter PBS5. , the third and fourth laser beams LB3 and LB4 are reflected by the fifth polarizing beam splitter PBS5 and are combined with the second laser beam LB2 to form the laser beam LBB . 2 is emitted from the light emitting portion LO2. In this case, the first laser beam LB1 is emitted as the laser beam LBC from the third light emitting portion LO3, and the output ratio between the laser beam LBB and the laser beam LBC is 3:1.

Also, the first half-wave plate HWP1 is retracted out of the optical paths of the third and fourth laser beams LB3 and LB4, and the third half-wave plate HWP3 is transmitted through the third polarization beam splitter PBS3. and placed on the optical paths of the third and fourth laser beams LB3 and LB4 until they enter the fifth polarizing beam splitter PBS5. By arranging the second half-wave plate HWP2 between and, the first to fourth laser beams LB1 to LB4 are all combined and emitted as the laser beam LB from the third light emitting portion LO3. be.

In this embodiment, either the first laser beam LB1 or the second laser beam LB2 is combined with the third laser beam LB3 and the fourth laser beam LB4 without changing the arrangement of the optical components. , it is possible to realize a configuration in which the output ratio of the laser beams LBA to LBC can be changed. However, there are fewer variations than the configurations shown in FIGS. 6A to 6C.

(Embodiment 3)
FIG. 7 shows a usage example of the laser processing apparatus according to this embodiment. Note that the laser oscillator 10 and the laser processing apparatus 100 shown in this embodiment have the same configurations as those shown in the first embodiment. That is, the first to fourth laser beams LB1 to LB4 are incident on the beam combiner 12 from the four laser modules 11, respectively, and are combined in the beam combiner 12 to form the laser beam LB that is emitted from the first light emitting portion LO1 or It is emitted from any one of the second light emitting portions LO2, or is divided in the beam combiner 12 and emitted from the first and second light emitting portions LO1 and LO2 as laser beams LBA and LBB, respectively. . The laser beam LB or LBA is emitted from the laser beam emission head 30 via the transmission fiber 40, and the laser beam LB or LBB is emitted from the laser beam emission head 31 via the transmission fiber 41. .

For example, as shown in the upper left and upper right (switching) of FIG. 7 , the laser beam LB is emitted to the workpiece 60 in different time zones by switching the light emitting portion and the laser beam emitting head from which the laser beam LB is emitted. Therefore, the operation rate of the laser processing apparatus 100 can be improved by eliminating the stop time of the laser oscillator 10 that occurs when the workpiece 60 is carried in and out. Further, as shown in the lower left of FIG. 7 (distribution 1), for example, by emitting laser beams LBA and LBB of the same output from the laser beam emitting heads 30 and 31, respectively, the number of workpieces 60 to be processed at the same time is increased. It is possible to improve the productivity in the laser processing process. Further, as shown in the lower right (distribution 2) of FIG. It is also possible to improve the processing quality of 60. For example, when the workpiece 60 is a metal plate coated with a plating film, the plating film is removed by a low-power laser beam LBA emitted from the laser beam emission head 30, and then emitted from the laser beam emission head 31. It is possible to weld the workpiece using the high-power laser beam LBB and improve the welding quality of the welded portion.

Note that the laser oscillator 10 shown in the second embodiment may be mounted on the laser processing apparatus 100 . In that case, three laser beam emitting heads emit laser beams at different times or at the same time. Also, the number of light emitting units in the laser oscillator 10 and the number of transmission fibers and laser beam emitting heads in the laser processing apparatus 100 may be further increased.

By doing so, the number of workpieces 60 that can be processed at the same time increases, and the productivity of the laser processing process can be further improved.

With the laser oscillator according to the present invention, it is possible to switch the light emitting portion for emitting the laser beam and change the output ratio of the laser beams emitted from the plurality of light emitting portions with a simple configuration. It is useful when applied to a laser processing device that processes a work of

10 Laser oscillator 11 Laser module 12 Beam combiner 20 Condensing units 30, 31 Laser beam emission heads 40, 41 Transmission fiber 50 Control unit 60 Work 70 Housing 100 Laser processing devices DP1 to DP3 First to third beam dampers
LB1 to LB4 1st to 4th laser beams
LI1 to LI4 First to fourth light entrance portions LO1 to LO3 First to third light exit portions M1 to M5 First to fifth mirrors ( first to fifth light reflecting members)
HWP1 to HWP4 first to fourth half- wave plates ( first to fourth polarizing members )
PBS1 to PBS6 1st to 6th polarizing beam splitters

Claims (13)

four laser modules each emitting first to fourth laser beams whose main polarization state is the first polarization state;
a beam combiner for combining the first to fourth laser beams respectively emitted from the four laser modules and emitting one or more laser beams;
a light condensing unit for condensing the laser beam emitted from the beam coupler so as to have a predetermined beam diameter and guiding the light to a transmission fiber;
The beam combiner is
first to fourth light incident portions on which the first to fourth laser beams are respectively incident;
first to fifth light reflecting members;
first to third polarizing beam splitters;
a first polarizing member and a second polarizing member;
having at least a first light emitting portion and a second light emitting portion;
the first light reflecting member reflects the first laser beam traveling in a first direction in a second direction crossing the first direction;
the second light reflecting member reflects the first laser beam reflected by the first light reflecting member in the first direction to direct it toward the first polarization beam splitter;
The third light reflecting member reflects the third laser beam traveling in the first direction in a second direction crossing the first direction to direct the beam toward the second polarization beam splitter. ,
the fourth light reflecting member reflects the fourth laser beam traveling in the first direction in the second direction to direct it toward the second polarizing beam splitter;
The third polarizing beam splitter travels in the first direction and directs the laser beam transmitted therethrough toward the first light emitting portion, while directing the laser beam reflected by itself to the fifth direction. Direct it toward the light reflecting member,
the fifth light reflecting member directs the incident laser beam toward the second light emitting portion;
The first polarizing member is positioned at a predetermined position on an optical path of the third laser beam and the fourth laser beam passing between the second polarizing beam splitter and the third polarizing beam splitter. and a predetermined position outside the optical path,
The second polarizing member is positioned at a predetermined position on an optical path of the first laser beam and the second laser beam passing between the first polarizing beam splitter and the third polarizing beam splitter. and a predetermined position outside the optical path,
By changing the positions of the first polarizing member and the second polarizing member while the first to fourth laser beams are incident on the first to fourth light incident portions, respectively, A laser oscillator, wherein the output of at least one of the laser beams emitted from the first light emitting portion and the second light emitting portion can be changed in four stages. The laser oscillator according to claim 1,
The first polarization member is moved to a predetermined position on the optical path of the third laser beam and the fourth laser beam, and the second polarization member is moved between the first laser beam and the second laser beam. By moving to a predetermined position outside the optical path with the laser beam of
a laser beam obtained by combining the first to fourth laser beams is emitted from the first light emitting portion;
While moving the first polarizing member to a predetermined position outside the optical paths of the third laser beam and the fourth laser beam, moving the second polarizing member between the first laser beam and the second laser beam. By moving to a predetermined position on the optical path with the laser beam of
A laser oscillator, wherein a laser beam obtained by combining the first to fourth laser beams is emitted from the second light emitting portion. 3. The laser oscillator according to claim 1, wherein
The first polarization member is moved to a predetermined position on the optical path of the third laser beam and the fourth laser beam, and the second polarization member is moved between the first laser beam and the second laser beam. By moving to a predetermined position on the optical path with the laser beam of
A laser beam obtained by combining the third laser beam and the fourth laser beam is emitted from the first light emitting portion, and the first laser beam and the first laser beam are emitted from the second light emitting portion. 1. A laser oscillator that emits a laser beam that is a combination of two laser beams. The laser oscillator according to any one of claims 1 to 3,
The first polarizing member is moved to a predetermined position on the optical path of the third laser beam and the fourth laser beam, and the second polarizing member is moved between the first laser beam and the second laser beam. to a predetermined position on the optical path of only one of the laser beams of
or,
moving the first polarizing member to a predetermined position on the optical path of only one of the third laser beam and the fourth laser beam, and moving the second polarizing member to the first laser beam and the second laser beam by moving to a predetermined position outside the optical path,
A laser beam obtained by combining three of the first to fourth laser beams is emitted from the first light emitting portion, and the first to fourth laser beams are emitted from the second light emitting portion. 1. A laser oscillator characterized by emitting one of the laser beams. The laser oscillator according to any one of claims 1 to 3,
The first polarizing member is moved to a predetermined position outside the optical paths of the third laser beam and the fourth laser beam, and the second polarizing member is moved to the first laser beam and the second laser beam. By moving only one of the laser beams to a predetermined position on the optical path,
One of the first to fourth laser beams is emitted from the first light emitting portion, and three of the first to fourth laser beams are emitted from the second light emitting portion. A laser oscillator, characterized in that it emits a laser beam in which 5. The laser oscillator according to claim 2 or 4,
the laser beam emitted from the first light emitting unit is a combined laser beam in which three or four laser beams are combined;
The laser oscillator according to claim 1, wherein the combined laser beams include at least one set of two laser beams combined so as to have the same optical axis by the third polarization beam splitter. four laser modules each emitting first to fourth laser beams whose main polarization state is the first polarization state;
a beam combiner for combining the first to fourth laser beams respectively emitted from the four laser modules and emitting one or more laser beams;
a light condensing unit for condensing the laser beam emitted from the beam coupler so as to have a predetermined beam diameter and guiding the light to a transmission fiber;
The beam combiner is
first to fourth light incident portions on which the first to fourth laser beams are respectively incident;
a third light reflecting member and a fourth light reflecting member;
first to sixth polarizing beam splitters;
a first polarizing member, a third polarizing member, and a fourth polarizing member;
and at least first to third light emitting portions,
The third light reflecting member reflects the third laser beam traveling in the first direction in a second direction crossing the first direction to direct the beam toward the second polarization beam splitter. ,
the fourth light reflecting member reflects the fourth laser beam traveling in the first direction in the second direction to direct it toward the second polarizing beam splitter;
The first polarizing beam splitter is provided on the optical path of the second laser beam traveling in the first direction and between the second light entrance section and the fifth polarizing beam splitter. be
The second polarizing beam splitter is provided on an optical path between the third laser beam reflected by the third light reflecting member and the fourth laser beam reflected by the third light reflecting member. be
the third polarizing beam splitter directs a laser beam transmitted through itself toward the fifth polarizing beam splitter, and directs a laser beam reflected by itself toward the first light emitting section;
The fourth polarizing beam splitter is provided on the optical path of the first laser beam traveling in the first direction and between the first light entrance section and the sixth polarizing beam splitter. be
The fifth polarizing beam splitter is provided on each optical path of the second laser beam transmitted through the first polarizing beam splitter and the laser beam transmitted through the third polarizing beam splitter,
The sixth polarizing beam splitter is provided on each optical path of the first laser beam transmitted through the fourth polarizing beam splitter and the laser beam transmitted through the fifth polarizing beam splitter,
The first polarizing member moves between a predetermined position on the optical path of the laser beam passing between the second polarizing beam splitter and the third polarizing beam splitter and a predetermined position outside the optical path. provided that it is possible to
The third polarizing member moves between a predetermined position on the optical path of the laser beam passing between the third polarizing beam splitter and the fifth polarizing beam splitter and a predetermined position outside the optical path. provided that it is possible to
The fourth polarizing member moves between a predetermined position on the optical path of the laser beam passing between the fifth polarizing beam splitter and the sixth polarizing beam splitter and a predetermined position outside the optical path. provided that it is possible to
By changing the positions of the first, third, and fourth polarizing members while the first to fourth laser beams are incident on the first to fourth light incident portions, respectively, A laser oscillator, wherein laser beams are emitted from first to third light emitting portions, respectively, and output of each laser beam can be changed. The laser oscillator according to claim 7,
A laser oscillator, wherein laser beams are simultaneously emitted from each of said first to third light emitting portions. The laser oscillator according to claim 7,
the beam combiner further comprising a second polarizing member;
The second polarizing member has a predetermined position on the optical path of the second laser beam passing between the first polarizing beam splitter and the third polarizing beam splitter and a predetermined position outside the optical path. provided movably between
By changing the positions of the first to fourth polarizing members while the first to fourth laser beams are incident on the first to fourth light incident portions, respectively, A laser oscillator, wherein the output of at least one of the laser beams emitted from the third light emitting portion can be changed in three stages. The laser oscillator according to any one of claims 1 to 9,
A plurality of the condensing units are provided according to the number of laser beams that are combined in the beam combiner and emitted out of the beam combiner, and the transmission fiber is provided in each of the plurality of condensing units. A laser oscillator characterized by being connected. a laser oscillator according to claim 10;
a laser beam emission head attached to each of the emission ends of the plurality of transmission fibers;
a controller that controls operations of the first polarizing member and the second polarizing member, or controls operations of at least the first polarizing member and the third and fourth polarizing members. A laser processing device characterized by: In the laser processing apparatus according to claim 11,
Varying the positions of the first and second polarizing members within the beam combiner or varying the positions of at least the first, third and fourth polarizing members within the beam combiner A laser processing apparatus characterized in that a laser beam emitting head for emitting a laser beam can be switched. In the laser processing apparatus according to claim 11 or 12,
Varying the positions of the first and second polarizing members within the beam combiner or varying the positions of at least the first, third and fourth polarizing members within the beam combiner A laser processing apparatus characterized by being configured so as to be able to change the output ratio of laser beams respectively emitted from a plurality of laser beam emitting heads.

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