Interconnecting devices and laser systems equipped with interconnecting devices

Abstract

An interconnecting device for interconnecting a laser device and an application device is disclosed. The interconnecting device comprises at least an optical fiber, an optical switch, and an output unit for outputting a laser beam to the application device. The interconnecting device is configured to receive a laser beam from the laser device and to deliver the laser beam to the application device. The optical switch is located after the optical fiber and is configured to modulate the amplitude of the laser beam. A laser system comprising the laser device and the interconnecting device is further disclosed. The drift of the laser beam is compensated before it is received in the interconnecting device.

Description

Technical Field

[0001] The present invention relates to the technical field of laser systems and devices for interconnecting a laser system with an application device.

Background Art

[0002] Laser systems, particularly pulsed laser systems, offer many advantages in various fields such as material processing, medical applications such as ophthalmology, and scientific research. However, these systems face the problem of laser beam drift, which can have an undesirable impact on the laser output and limit its performance. Drift in pulsed lasers is mainly caused by fluctuations in operating conditions such as temperature, power supply stability, non-linear effects in the laser cavity, and operating mode. New techniques and technologies are needed to overcome and mitigate these drift problems.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The object of the present disclosure is to provide devices and systems for addressing the problem of laser beam drift in laser systems. The described solutions aim to improve the stability and accuracy of laser output, reduce downtime and maintenance, and enhance the overall performance of pulsed laser systems.

Means for Solving the Problems

[0004] This object is met by the interconnecting device according to claim 1 and the system according to claim 16 or claim 17. Preferred embodiments of the present invention are described in the dependent claims.

[0005] In a first aspect, an interconnection device for interconnecting a laser device and an application device is disclosed. The interconnection device comprises at least an optical fiber, an optical switch, and an output unit. The interconnection device is configured to receive a laser beam from the laser device and deliver the laser beam to the application device. The optical fiber is located at the input of the interconnection device, and the optical switch is located after the optical fiber. The optical switch is configured to modulate the amplitude of the laser beam. The output unit outputs the laser beam to the application device.

[0006] By providing an interconnect device with a fiber at its input, a simple, reliable, and user-friendly coupling to the laser device is ensured. Furthermore, by providing an optical switch in the interconnect device, it is ensured that the user of the application device can control the delivery of the laser beam to the application device while the laser beam reaches the switch as a continuous and reliable laser signal. Finally, by providing an interconnect device with a switch after the laser device and immediately before the application device, it is ensured that laser drift is compensated before the optical switch so that the optical switch does not affect the laser beam. In other words, laser beam drift is compensated before the critical fiber coupling interface (i.e., before the optical fiber) and before the switch, and the optical switch does not affect the laser beam position and angle at the critical fiber coupling interface.

[0007] An interconnecting device for interconnecting a laser device and an application device is understood as a device having optical inputs and optical outputs that are conveniently attached to both the laser device and the application device by the user of the application device.

[0008] A laser device is configured to deliver a laser beam to an interconnect device. The laser device may be configured to deliver a pulsed laser beam. The laser beam is generated by a laser source and typically drifts within the laser device. The laser device or interconnect device may be configured to compensate for the laser beam drift. The laser device may include an amplifier for delivering an amplified laser beam with a high total average power of 1 kW or more.

[0009] An application device is understood as a device that delivers a laser beam to a user and can be designed according to the user's needs and / or specific application. In some examples, an application device may be a surgical delivery device, such as a surgical device for ophthalmic surgery. An application device may also be called a delivery device or processing head. When the laser beam is received by the application device, the laser beam must be stable and reliable, and its parameter variations must be minimal so that the user can perform the desired application with the desired precision. This can be achieved by placing an interconnect device in front of the application device.

[0010] The optical fiber may be placed at the input of the interconnect device. The use of optical fiber in the interconnect device enables the delivery of a laser beam from the laser device to the application device, while simultaneously ensuring reliable coupling of the laser beam from the laser device. Any laser beam drift can be compensated for before the laser beam is coupled to the fiber.

[0011] In some embodiments, the optical fiber is a solid-core fiber. The solid-core fiber may include step-index fibers, photonic crystal solid-core fibers, and the like. Typically, the solid-core fiber may be used to guide a continuous laser beam or a pulsed laser beam having long pulses, such as pulses longer than 100 ns and pulses with low peak power.

[0012] In some embodiments, the optical fiber may be a hollow-core fiber. A hollow-core fiber (HCF) is an optical fiber having a hollow core surrounded by a thin layer of cladding material. HCFs can induce laser pulses with high peak power (e.g., ps and fs pulses) without damaging the fiber. This is because the light is confined to the central hollow core, and therefore the interaction between the light and the cladding material is reduced. The core may be evacuated or filled with air or other gases. Preferably, when the pulse is ultrashort (e.g., 100 ps or less) and has high peak power (e.g., 1 kW or more), the core of the HCF is evacuated (i.e., a vacuum exists in the core) because other media present in the core can cause pulse distortion. The use of HCFs in interconnect devices can enable high-peak-power delivery of the laser beam from the laser device to the application device, while simultaneously compensating for reliable coupling of the laser beam from the laser device. Any drift of the laser beam can be compensated for before the laser beam is coupled to the interconnect device.

[0013] In some embodiments, the HCF may be a hollow-core photonic crystal fiber (HC-PCF). A key feature of the HC-PCF is the presence of a periodic pattern of air holes running along the length of the fiber. These air holes generate a photonic bandgap, i.e., a range of wavelengths in which light propagation is prohibited. The bandgap prevents the guided light from leaking into the cladding, thereby confining the guided light within the hollow core. HC-PCFs are used to deliver laser beams with high peak power and high-quality mode profiles, enabling applications in laser material processing, medical applications such as surgery, scientific research, etc. In some embodiments, the HCF may be an anti-resonant hollow-core photonic crystal fiber (AR-HC-PCF). In some embodiments, the HCF may be a revolver hollow-core fiber. In some embodiments, the HCF may be a hollow-core photonic bandgap fiber. In some embodiments, the HCF may be a hollow glass waveguide based on fused silica capillary tubes.

[0014] In this context, an optical switch may be understood as a device used to control the transmission of light, for example, by blocking or enabling the passage of light through an interconnect device to an application device, or by modulating the frequency of a pulse, or similarly. An optical switch may be an amplitude modulation device, an amplitude control device, or a shutter. An optical switch may be a switching device such as an acousto-optic modulator (AOM) or an electro-optic modulator (EOM). AOMs and EOMs are preferred due to their ultrafast response. The optical switch may be used and controlled by the user of the application device so that light is delivered as requested by the user. Alternatively, the optical switch may be automatically controlled via a control unit of the laser system.

[0015] The interconnect device is configured to receive a laser beam from the laser device and deliver the laser beam to the application device. Only after the optical fiber is an optical switch placed to enable customizable output from the interconnect device to the application device.

[0016] In some embodiments, the optical switch is configured to control the delivery of a laser beam to an application device. In some examples, the switch may completely block the laser beam from entering the application device so that no light is delivered to the application device. In some examples, the switch may be configured to allow more than 50% of the laser beam to pass through an interconnect device so that all light can enter the application device. The optical switch may be free-space based so that the laser beam from an optical fiber (or an intermediate component placed between the optical fiber and the switch) is delivered into free space and then coupled to the optical switch. The optical switch may be implemented by a mechanical shutter, EOM, or AOM.

[0017] In some embodiments, the optical switch is configured to allow a laser beam or a portion thereof to be transmitted to an application device. The user of the application device may control the optical switch to ensure the laser beam is delivered to the application device. In some embodiments, the optical switch may be automatically controlled. Automatic control of the switch may rely on laser beam drift compensation occurring before the laser beam enters the interconnect device. That is, if the laser beam drift is compensated and the laser beam is efficiently coupled to the interconnect device, the switch may be automatically configured to allow the optical beam to pass toward the application device. This feature of the switch can be used when the application device requires a constant delivery of the laser beam.

[0018] In some embodiments, the optical switch is configured to block the transmission of a laser beam to an application device. The user of the application device may control the optical switch to block the laser beam and therefore prevent it from being delivered to the application device. In some embodiments, the optical switch may be controlled automatically. Automatic control of the switch may rely on laser beam drift compensation that occurs before the laser beam enters the interconnect device. That is, if the laser beam drift is not compensated and the laser beam is not efficiently coupled to the interconnect device, the switch may be automatically configured to block any optical beam delivery toward the application device. This feature of the switch can be used as a precaution to protect the application device and / or the final point to which the laser beam is to be delivered by the application device.

[0019] In some embodiments, an optical switch is configured to receive an external input and thereby control the delivery of a laser beam to an application device. The external input may be received from the user of the application device, thereby delivering the laser beam to the application device at the user's request. Alternatively, or in addition to this, the external input may be received from a sensor configured to compensate for laser beam drift in the laser device and / or to detect power received in the interconnect device. In some embodiments, the interconnect device may further include a post-compression unit configured to temporally compress the laser beam pulses. The post-compression unit may be located after the optical switch. The post-compression unit may be a free-space component configured to receive the laser beam from the optical switch through free space. The post-compression unit may be controlled by a control unit depending on the required end application of the laser beam. The post-compression unit may be configured to reduce the pulse duration to the range of ps or fs. The post-compression unit may further direct the laser beam towards the output of the interconnect device. Alternatively, the interconnect device may include a pulse stretcher configured to temporally extend the laser pulses.

[0020] In some embodiments, the output unit includes a beam collimator configured to collimate a laser beam and deliver it to an application device. The beam collimator may also be a free-space based component that receives the laser beam from an optical switch / compressor / stretcher through free space. The beam collimator ensures that the laser beam is collimated, has low divergence, and is therefore delivered to the application device to improve accuracy and efficiency at the end application. The output unit may also include a processing camera configured to track the quality of the incident light beam and optionally control the collimator accordingly.

[0021] The output unit may include a power sensor configured to monitor the output power received by the output unit from the optical fiber. The power sensor may be fixed during the operation of the application device. In other words, the power sensor may always form an integral part of the output unit to monitor the power output from the optical fiber and received by the output unit, and may not be removed or repositioned at different times during operation or calibration. The power sensor may provide a feedback signal configured to optimize the coupling of the laser beam to the optical fiber. Coupling optimization based on this feedback signal may exceed the accuracy of the position and angle sensors provided in the fiber coupling unit. The power sensor may also be used to recalibrate the position and angle sensors of the fiber coupling unit. In some cases, recalibration may be necessary because mechanical deformation of the housing of the fiber coupling unit may occur over time. In addition, various changing conditions may result in degradation of the reference position / angle signal in the fiber coupling unit. The output unit may be equipped with a first reference sensor, and the fiber coupling unit may be equipped with a second reference sensor. The first and second reference sensors communicate with a local area network and are then used to detect any discrepancies in readings through the local network, and may act as a safety mechanism to protect the fiber and application devices.

[0022] The output unit may include an energy measurement device. The output unit may further include a peak power measurement device, such as a two-photon absorption photodiode (TPA PD). In some embodiments, the output unit may include a spectrometer configured to monitor the optical spectrum. In some embodiments, the output unit may include a total pulse width measurement device configured to directly measure the pulse width of the laser beam pulse.

[0023] In some embodiments, the optical switch may form part of the output unit. Typically, the optical switch may be arranged after various sensors of the output unit. Such a configuration allows for a continuous input of the laser beam to the sensors of the output unit, and then the output unit may provide feedback to the fiber coupling unit for additional coupling optimization and additional drift compensation of the laser beam to the optical fiber.

[0024] In some embodiments, the laser beam is delivered to the output unit in free space. Typically, aside from the optical fiber, all components of the interconnect device are free space optical components capable of transmitting high peak power ultrashort laser pulses. The same applies to the output section.

[0025] In some embodiments, the interconnect device comprises a free space output connector for connecting to an application device. The free space output connector may be configured to be removably attached to the application device.

[0026] In some embodiments, the interconnect device further comprises a fiber coupling unit arranged upstream of the optical fiber and configured to output the laser beam to the optical fiber, and the fiber coupling unit is configured to compensate for the drift of the laser beam.

[0027] In most embodiments, an optical fiber such as a hollow core fiber is connected to the fiber coupling unit. In a preferred embodiment, the fiber coupling unit is arranged as an internal component of the interconnect device.

[0028] In another preferred embodiment, the fiber coupling unit is arranged outside the interconnect device. In the most preferred embodiment, the interconnect device is a non-integral part of the laser device. This, together with the above preferred embodiments, may allow for flexible adjustment / modification of the laser device.

[0029] The fiber coupling unit may include an active alignment system configured to compensate for laser beam drift. The active alignment system may include an alignment sensor and beam steering means. The alignment sensor may be configured to detect characteristics of the laser beam and provide input to the beam steering means. The beam steering means may be configured to steer the laser beam according to the detected characteristics so that the laser beam is aligned with the input of the fiber coupling unit and guides and steers the beam into the optical fiber. The beam steering means may include one or more mirrors, movable mirrors, rotating wedges, acousto-optic deflectors, etc., or any combination thereof. The beam steering means may include a controller. The controller may receive input from the alignment sensor and control the mirrors, wedges, deflectors, etc., according to the input received from the alignment sensor. In some embodiments, the fiber coupling unit includes a fiber coupler configured to connect to the optical fiber.

[0030] In a second embodiment, a laser system is disclosed comprising a laser device and an interconnection device according to the first embodiment. In this embodiment, laser beam drift may be compensated in the interconnection device or laser device, which typically comprises a fiber coupling unit.

[0031] In conventional systems utilizing ultrafast laser beams with pulses typically having high peak power, the free-space component is primarily used. The optical switch is typically located immediately after the laser source and before any beam alignment system for delivering the beam to the application device. In these systems, the optical switch is typically controlled by the user. The optical switch is opened only for the relatively short actual processing time required by the application device. While the optical switch is blocking the beam, there is no knowledge of where the beam will emerge when the switch is opened after some idle time. In other words, the beam alignment system, with its sensors (position / angle and power sensors), is almost always blind and unable to track the beam or compensate for beam pointing drift. This uncertainty leads to a high risk of damaging the fiber input surface and other components in the laser system, ultimately resulting in the application device not receiving the desired laser beam to perform the desired task, thereby reducing the application device's performance. Prediction based on activity / inactivity times is difficult and unreliable. Therefore, a system is needed that reliably delivers the laser beam to the application device.

[0032] The shortcomings of known technologies are solved by the present invention by modifying the architecture of the laser system and placing the optical switch only after laser drift has been compensated. The optical switch can be one of the sources of laser beam drift when placed immediately after the laser source due to the thermal load that changes when the switch is operating. Placing the optical switch after the laser device and after the fiber is to ensure that a continuous and reliable signal is present in the position / angle / power sensors of the fiber coupling unit. This allows for compensation of beam drift and ensures optimal coupling to the fiber.

[0033] According to the second embodiment, laser drift is compensated in the interconnect device by a fiber coupling unit positioned before the optical fiber and switch. According to the third embodiment, laser drift is compensated in the laser device, i.e., before the interconnect device comprising the fiber, switch, and output unit. The second and third embodiments differ in the arrangement of the fiber coupling unit; i.e., in the second embodiment, the fiber coupling unit forms part of the interconnect device, and in the third embodiment, the fiber coupling unit forms part of the laser device.

[0034] In a third embodiment, a laser system is disclosed comprising a laser device and an interconnecting device comprising a fiber, a switch, and an output unit. The drift of the laser beam is compensated before it is received in the interconnecting device. Thus, the laser system comprises a laser device connected to the interconnecting device. The laser system can be connected to an application device via the interconnecting device. More specifically, the laser system comprises a laser device that can be connected to an optical fiber, the optical fiber is connected to an optical switch, and the switch is connected to an output unit configured to be connected to an application device. A key feature of the third embodiment is that the drift of the laser beam is compensated in the laser device so as to ensure optimal coupling with the fiber before the interconnecting device, before the optical switch, and therefore before the application device.

[0035] A laser beam generated by a laser source can drift for many different reasons. The laser beam may exhibit long-term drift, starting drift, temperature drift, etc. Temperature drift is caused by changes in temperature. Similar drift in the laser beam can result from changes in pressure or humidity in the environment through which the beam passes. Furthermore, mechanical vibrations or movement of the apparatus or support structure can cause small misalignments in the optical components or mirrors through which the beam passes, leading to the laser beam drifting off its desired path. Additionally, any amplitude modulation of the laser beam can cause laser beam drift.

[0036] An interconnect device equipped with optical fibers such as HCF, along with a switch, is configured to receive a laser beam from a laser device and deliver the laser beam to an application device. The optical fiber is placed at the input of the interconnect device, and the optical switch is placed after the fiber. The optical fiber ensures accurate and convenient coupling with the laser device and further delivery to the application device through the output unit. In such a system, laser drift is compensated for before the interconnect device and optical switch, resulting in a reliable laser system that delivers an accurate and reliable laser beam to the application device.

[0037] In some embodiments, the laser device comprises a pulsed laser source configured to generate a laser beam and a fiber coupling unit configured to output the laser beam to an interconnect device. The pulsed laser source is positioned to deliver the laser beam to the fiber coupling unit. The laser beam may be delivered from the laser source to the fiber coupling unit through free space.

[0038] The pulsed laser source may be configured to generate nanosecond, picosecond, or femtosecond pulses. The pulsed laser source may include a compressor for temporally compressing the laser pulses. The pulsed laser source may generate pulses with high peak power, such as over 1 kW, and high total power. The laser source may be a supercontinuous light source extending from the visible spectrum to the infrared spectrum. Pulsed lasers are widely used in various fields, including industrial material processing, medical applications, biomedical imaging and diagnosis, microfabrication, and 3D printing. Therefore, using a pulsed laser source in this laser system is beneficial and enables a wide range of application devices.

[0039] The fiber coupling unit may include a free-space component configured to guide and couple light to an interconnecting device, i.e., to an optical fiber such as a solid core fiber or HCF. The fiber coupling unit ensures a continuous and reliable signal to the optical fiber.

[0040] In some examples, the fiber coupling unit includes an active alignment system configured to compensate for laser beam drift. The active alignment system may be configured to track the laser beam from the laser source and to dynamically reposition the laser beam so that optimal coupling between the laser device and the interconnect device is achieved. While the laser source is operating, the fiber coupling unit continuously receives the laser beam from it, thereby continuously compensating for any drift in the laser beam. When the laser source is turned off, there is no input beam, so the active alignment system is also off. When the laser is turned on, the active alignment system also turns on, making it possible to actively compensate for the laser's starting drift. Having an active alignment system that continuously receives the laser beam is beneficial because it ensures optimal coupling of the beam with the optical fiber.

[0041] In some examples, an active alignment system comprises an alignment sensor and beam steering means, such as a steering mirror. The alignment sensor may be configured to detect characteristics of a laser beam and provide input to the beam steering means. The beam steering means may be configured to steer the laser beam according to the detected characteristics so that the laser beam aligns with the output of a fiber coupling unit. Alternatively or in addition to this, a rotating wedge, an acousto-optic deflector, etc., may be used. The output of the fiber coupling unit may be a fiber coupler. The alignment sensor may comprise any type of position sensing device, such as one or more cameras based on a CCD or CMOS chip, a PSD photodiode, a four-quadrant photodiode, or other devices configured to track the path of the laser beam. The steering mirror may be an electric mirror driven by a controller. The controller may receive measurements from the alignment sensor and drive the mirror to provide optimized optical coupling between the laser device and the interconnecting device. The mirror may be continuously steered so that optimal alignment is always achieved.

[0042] The fiber coupling unit may include additional sensors (e.g., check sensors such as power sensors and / or pulse energy sensors) configured to track the active alignment system and provide confirmation signals containing information about the alignment between the laser device and the interconnect device. The confirmation signals may be available to the user of the application device and to the optical switch. If the confirmation signals indicate that the laser beam is not aligned with the interconnect device, the optical switch may be disabled, or the user of the application device may be warned not to operate the switch. Once alignment is achieved and drift is compensated, the confirmation signals may enable the switch and / or allow the user to operate the switch as required by the application device. It is beneficial to have a check sensor in the fiber coupling unit to ensure that the user can only use the laser beam when the active alignment system has compensated for laser beam drift. Alternatively, the check sensor may be located on the interconnect device prior to the optical fiber.

[0043] Power and / or pulse energy sensors may be used at the inputs and outputs of the fiber coupling unit. Their output signals may be tracked over time, and changes in the signals may be used to track whether damage or mismatch with the fiber is occurring. Power and / or pulse energy sensors may be used to generate warnings or blocking actions if the beam drift is too large before compensation begins.

[0044] Beam drift compensation does not always need to be active. In some cases, drift compensation during application device operation may not be acceptable. Re-optimization may be performed at a later time, for example, during the application device's idle time.

[0045] In some embodiments, the check sensor may be configured to automatically disable the optical switch and put it into shut-off mode, i.e., to prevent light from being delivered to the application device, if the alignment system fails to compensate for the drift. This may occur in situations where the drift is too severe for the active alignment system to respond to the change in a timely manner. In these cases, there may be a sudden drop in power delivered through the optical fiber. This feature may be used as a means of protecting the application device.

[0046] In some examples, the fiber coupling unit includes an output fiber coupler configured to connect to the optical fiber of the interconnecting device. The steering means of the fiber coupling unit may be configured to couple the light to the fiber coupler. The fiber coupler ensures a simple, convenient, and reliable connection between the laser device and the interconnecting device.

[0047] In some examples, the laser device further comprises a compressor configured to temporally compress pulses of the laser beam. The pulse compressor in the laser device may be controlled by a control unit. The control unit may receive input from the user of the application device. The pulse compressor may be a free-space component that receives the laser beam from the laser source and further delivers the light through free space to a fiber coupling unit, its sensors, and mirrors. In some examples, the laser system may comprise only one pulse compressor located in the laser device. In this case, other compressors in the interconnect device may be omitted. In some examples, the laser system may comprise two or more compressors, one or more pulse compressors forming part of the laser device and one or more pulse compressors forming part of the interconnect device.

[0048] In some embodiments, the laser source may be a continuous-wave (CW) laser, or a pulsed laser such as a pulsed diode or fiber laser, q-switched laser, or mode-locked laser configured to provide a laser beam. The laser source may include one or more lasers.

[0049] example The embodiments described above, the appended claims, and / or the examples disclosed above and below in this specification can be appropriately combined with each other, as will be apparent to those skilled in the art.

[0050] A laser system may include a pulsed laser source that generates a pulsed laser beam. The pulsed laser beam may be temporally compressed or stretched by a pulse compressor or pulse stretcher, depending on the application. The pulsed laser beam may have high peak power and high total power (e.g., higher than 1 kW). Such a laser beam with high total / peak power may be coupled to an optical fiber. Different optical fibers may be used depending on the values ​​of peak power and pulse duration. For example, a hollow core fiber may be used for ultrashort pulses (e.g., less than 100 ps) with high peak power (e.g., greater than 1 kW). A solid core fiber may be used for lower peak power and longer pulses (e.g., longer than 100 ns at a peak power of 1 W). To ensure efficient coupling to an optical fiber (HCF or solid core), the pulsed laser beam may be guided through free space to a system of steering means (e.g., electric mirrors) and sensors configured to compensate for laser beam drift and cause the laser beam to change its path. The optical fiber may then deliver a laser beam to an application device operated by the user. The user may, as required, control the delivery of the laser beam to the application device. Therefore, the laser system may include a switch or shutter configured to control the delivery of the laser beam to the application device. The switch may be located downstream of the optical fiber, after which the laser beam can be delivered to the application device through an output unit such as an output collimator. If necessary, the laser beam may be further temporally compressed / expanded before delivery to the application device. Therefore, a compressor / stretcher may be located downstream of the switch for further pulse duration modulation. The switch may also be configured to change the repetition rate of the laser beam as required by the application device.

[0051] Additional features and advantages are disclosed in the following description, claims, and drawings, some of which will be readily apparent to those skilled in the art from there, or will be recognized by implementing this disclosure as described herein. It should also be noted that all features described in relation to the first aspect are combined with the features described in the second and third aspects. Furthermore, the features of the second aspect are combined with the features described in relation to the third aspect, and the features of the third aspect are combined with the features described in relation to the second aspect.

[0052] Preferred embodiments of the present invention are described below, merely as examples, with reference to the accompanying drawings. [Brief explanation of the drawing]

[0053] [Figure 1] A diagram illustrating the implementation of conventional laser systems. [Figure 2] A diagram illustrating an exemplary embodiment of the laser system relating to this disclosure. [Figure 3] A figure showing another exemplary embodiment of the laser system relating to this disclosure. [Figure 4] A diagram showing one exemplary implementation of the interconnection device relating to this disclosure. [Figure 5] A diagram showing another exemplary implementation of the laser system related to this disclosure. [Figure 6] A diagram showing yet another exemplary implementation of the laser system related to this disclosure. [Modes for carrying out the invention]

[0054] Figure 1 shows a prior art implementation of the laser system 100. In conventionally used systems, the optical switch 104 is typically located immediately after the laser source 102 and before any beam alignment system 108 for delivering the beam 10 to the application device 114. In the prior art system 100, the optical switch 104 may be followed by a pulse compressor 106, a beam alignment system 108, and a collimator 112 for delivering the laser beam to the application device 114. The optical switch 104 is typically controlled by the user. The switch 104 is opened only for the relatively short actual processing time required by the application device 114. At that point, there is no knowledge of where the beam will come from when the switch 104 is opened after some idle time. In other words, the beam alignment system 108, which has its sensors, is in most cases blind and unable to track the beam and compensate for beam pointing drift. Finally, the application device 114 may not receive the desired laser beam. Therefore, there is a need for a system that can reliably deliver a laser beam to application devices.

[0055] The shortcomings of known technologies are solved by the present invention, which modifies the architecture of the laser system 100, places the optical switch 104 only when laser drift is compensated for, and further utilizes optical fibers.

[0056] Figure 2 shows an exemplary embodiment of a laser system 200 according to the present disclosure. The laser system 200 comprises a laser device 201 and an interconnection device 220. The interconnection device comprises an optical fiber 210, a switch 204, and an output unit 212. The optical fiber 210 is configured to receive a laser beam 10 from the laser device 201 and deliver the laser beam 10 to an application device 114. The optical fiber 210 may be located at the input of the interconnection device 220, and the optical switch 204 is located downstream of the optical fiber 210. The optical fiber 210 ensures accurate and convenient coupling with the laser device 201 and further delivery to the application device 114 through the output unit 212. In such a system, laser drift is compensated before the interconnection device 220 and the optical switch 204, which could also be a source of laser drift. The switch 204 is located close to the application device 114, and as a result, the reliable laser system 200 delivers an accurate and reliable laser beam 10 to the application device 114.

[0057] Figure 3 shows another exemplary embodiment of the laser system 300 according to the present disclosure. The laser system 300 comprises all components as shown in Figure 2, and the laser device 201 comprises a pulsed laser source 202 and a fiber coupling unit 208. The pulsed laser source is configured to generate a laser beam 10, and the fiber coupling unit 208 is configured to output the laser beam 10 to an interconnect device 220. As shown in this example, the interconnect device 220 is a non-integrated portion of the laser device 201. The pulsed laser source 202 is positioned to deliver the laser beam 10 to the fiber coupling unit 208. The laser beam 10 may be delivered from the laser source 202 to the fiber coupling unit 208 through free space. The fiber coupling unit 208 may include a free-space component configured to guide and couple the light to the interconnect device 220, i.e., to an optical fiber (e.g., HCF) 210. The fiber coupling unit 208 ensures a continuous and reliable signal to the optical fiber 210. The fiber coupling unit 208 typically includes an active alignment system (not shown) configured to compensate for the drift of the laser beam 10. As shown in the figure, the optical fiber 210 is connected to the fiber coupling unit 208. The active alignment system, which includes various sensors, detectors, motorized mirrors, etc., may be configured to track the laser beam from the laser source and to dynamically reposition the laser beam 10 so that optimal coupling between the laser device 201 and the interconnection device 220 is achieved. While the laser source 202 is operating, the fiber coupling unit 208 can continuously receive the laser beam 10, thereby continuously compensating for the drift of the laser beam 10. When the laser source 202 is turned off, there is no input beam, so the active alignment system is also off. When the laser 202 is turned on, the active alignment system is also turned on and may actively compensate for the laser starting drift. Having an active alignment system that continuously receives the laser beam can be beneficial as it ensures optimal coupling of the beam with the optical fiber 210.The laser source 202 may include a pulse compressor for temporal compression of the laser pulse. Alternatively, the compressor 206 may be located downstream of the laser source 202. Alternatively, or in addition to the above, the pulse compressor may be located in the interconnect device. The pulse compressor 206 may be replaced with a pulse stretcher as required by the application device.

[0058] Figure 4 shows one exemplary implementation of the interconnection device 220 according to the present disclosure. The interconnection device 220 is for interconnecting a laser device and an application device. The interconnection device 220 comprises at least an optical fiber 210, an optical switch 204, and an output unit 212. The interconnection device 220 is configured to receive a laser beam 10 from the laser device and to deliver the laser beam 10 to the application device. The optical fiber 210 is located at the input of the interconnection device 220. The optical switch 204 is located after the optical fiber 210 and is configured to modulate the amplitude of the laser beam 10. The output unit 212 is configured to output the laser light to the application device.

[0059] Figure 5 shows an exemplary embodiment of a laser system 500 according to the present disclosure. The laser system 500 comprises a laser device 501 and an interconnection device 520. The interconnection device comprises a fiber coupling unit 208, an optical fiber 210, a switch 204, and an output unit 212. As shown in this example, the interconnection device 520 is a non-integrated portion of the laser device 501. While the laser device 501 is operating, the fiber coupling unit 208 can continuously receive the laser beam 10, thereby continuously compensating for any drift of the laser beam 10. The optical fiber 210 is configured to receive the laser beam 10 from the fiber coupling unit 208 and deliver the laser beam 10 to an application device 114. The optical switch 204 is located downstream of the optical fiber 210. The optical fiber 210 ensures the delivery of the laser beam to the application device 114 through the output unit 212. In such a system, laser drift may be compensated in the interconnect device 520 by a fiber coupling unit 208. As shown in Figure 5, the optical fiber 210 is connected to the fiber coupling unit 208. This compensation is performed before an optical switch 204, which can also cause laser drift. The switch 204 is located near the application device 114, so that the reliable laser system 500 delivers an accurate and reliable laser beam 10 to the application device 114. The laser source 202 may be equipped with a pulse compressor for temporal compression of the laser pulse. Alternatively, the compressor 206 may be located after the laser source 202. Alternatively, or in addition to the above, the pulse compressor may be located in the interconnect device. The pulse compressor 206 may be replaced with a pulse stretcher as required by the application device.

[0060] Figure 6 shows an exemplary embodiment of a laser system 600 according to the present disclosure. The laser system 600 comprises a laser device 501 and an interconnection device 620. The interconnection device comprises a fiber coupling unit 208, an optical fiber 210, a switch 204, and an output unit 612. The switch 204 forms part of the output unit 612. The output unit 612 further comprises various sensors 608, such as a power sensor, configured to monitor the output power received by the output unit 612 from the optical fiber 210. The output unit sensor 608 may provide the fiber coupling unit 208 with a feedback signal 622 (e.g., including information about the power delivered to the output unit) so that the fiber coupling unit can perform additional alignment of the laser beam and further compensate for laser beam drift. While the laser device 501 is operating, both the fiber coupling unit 208 and the output unit sensor 608 continuously receive the laser beam 10 and thereby continuously compensate for any drift of the laser beam 10. The optical switch 204 is positioned after the output unit sensor 608. In such a system, laser drift is compensated in the interconnect device 620 by a fiber coupling unit 208, which is further supported by the sensor 608. This compensation is performed before the optical switch 204, which could also cause laser drift. The switch 204 is positioned close to the application device 114, and as a result, the reliable laser system 600 delivers an accurate and reliable laser beam 10 to the application device 114.

[0061] The terms used herein are for describing specific aspects only and are not intended to limit the disclosure. Where used herein, the singular forms following “a,” “an,” and “the” are intended to include the plural forms unless the context explicitly indicates otherwise. Where used herein, the term “and / or” includes any and all combinations of one or more of the associated enumerated items. The terms “comprises,” “comprising,” “includes,” and / or “including,” where used herein, specify the presence of a described feature, integer, process, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, integers, processes, operations, elements, components, and / or groups thereof.

[0062] Relative terms such as "below," "above," "higher," or "lower" may be used herein to describe the relationship between one value and another. When an element is referred to as "connected" or "coupled" to another component, it is understood that the element may be directly connected or coupled to the other component, or there may be an intervening component. In contrast, when a component is referred to as "directly connected" or "directly coupled" to another component, there is no intervening element.

[0063] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as those generally understood by those skilled in the art to which this disclosure belongs. Terms used herein are to be interpreted as having meanings consistent with their meanings in the context of this specification and related art, and not to be interpreted in an idealized or overly formal sense unless expressly defined herein.

[0064] It should be understood that this disclosure is not limited to the embodiments described above and shown in the drawings. Rather, those skilled in the art will recognize that many changes and modifications can be made within the scope of this disclosure and the appended claims. The embodiments disclosed in the drawings and specification are for illustrative purposes only and not for limiting purposes, and the scope of the concept of the present invention is set out in the following claims. [Explanation of Symbols]

[0065] 10 laser beams 100-600 Laser System 102,202 laser sources 104,204 Optical switches 106,206 pulse compressors 108 Beam Alignment System 112 Collimator 114 Application Devices 201,501 Laser Devices 208 Fiber coupling unit 210 optical fibers 212,612 output units 220,520,620 Interconnected Devices 608 Output Unit Sensor 622 Feedback signal

Claims

1. An interconnection device for interconnecting a laser device and an application device, comprising at least a hollow core fiber, an optical switch, and an output unit, The interconnection device is configured to receive a laser beam from the laser device and to deliver the laser beam to the application device. The optical switch is positioned after the hollow core fiber and is configured to modulate the amplitude of the laser beam, and the output unit is configured to output the laser beam to the application device. The hollow core fiber is connected to a fiber coupling unit, which is positioned in front of the hollow core fiber and configured to output the laser beam to the hollow core fiber, and the fiber coupling unit is configured to compensate for beam drift of the laser beam. The fiber coupling unit is an interconnection device comprising an active alignment system configured to compensate for the beam drift of the laser beam.

2. The interconnect device according to claim 1, wherein the optical switch is configured to control the delivery of the laser beam to the application device.

3. The interconnect device according to claim 1 or 2, wherein the optical switch is configured to allow the laser beam or a portion of the laser beam to be transmitted to the application device.

4. The interconnect device according to claim 1 or 2, wherein the optical switch is configured to block the transmission of the laser beam to the application device.

5. The interconnect device according to any one of claims 1 to 4, wherein the optical switch is configured to receive an external input and thereby control the delivery of the laser beam to the application device.

6. The interconnect device according to any one of claims 1 to 5, further comprising a post-compression unit configured to temporally compress the pulses of the laser beam, wherein the post-compression unit is located after the optical switch.

7. The interconnect device according to any one of claims 1 to 6, wherein the output unit comprises a beam collimator configured to collimate the laser beam and deliver the laser beam to the application device.

8. The interconnect device according to any one of claims 1 to 7, wherein the active alignment system comprises an alignment sensor and a beam steering means, the alignment sensor is configured to detect characteristics of the laser beam and provide input to the beam steering means, and the beam steering means is configured to steer the laser beam according to the detected characteristics so that the laser beam aligns with the input of the fiber coupling unit.

9. The interconnection device according to claim 8, wherein the fiber coupling unit comprises a fiber coupler configured to connect to the hollow core fiber.

10. The interconnect device according to any one of claims 1 to 9, wherein the output unit comprises a power sensor configured to monitor power output from the optical fiber and received by the output unit, and the power sensor is further configured to provide a feedback signal for optimizing the coupling of the laser beam to the optical fiber.

11. The interconnect device according to claim 8 or 10, wherein the power sensor is configured to recalibrate the alignment sensor of the fiber coupling unit.

12. The interconnect device according to claim 10 or 11, wherein the output unit comprises a first reference sensor, the fiber coupling unit comprises a second reference sensor, and the first reference sensor and the second reference sensor are configured to communicate and exchange power measurements, and to further compare the exchanged measurements, and to act as a safety mechanism for protecting the optical fiber and the application device based on the comparison of the exchanged measurements.

13. The interconnect device according to any one of claims 1 to 12, wherein the fiber coupling unit is arranged as an internal component of the interconnect device.

14. The interconnect device according to any one of claims 1 to 13, wherein the fiber coupling unit is located outside the interconnect device.

15. The interconnect device according to any one of claims 1 to 14, wherein the interconnect device is a non-integrated portion of the laser device.

16. A laser system comprising a laser device and an interconnecting device according to claims 1 to 15, wherein the drift of the laser beam is compensated in the interconnecting device.

17. A laser system comprising a laser device and an interconnection device according to any one of claims 1 to 15, wherein the drift of the laser beam is compensated before it is received by the interconnection device.

18. The laser system according to claim 16 or 17, wherein the laser device comprises a pulsed laser source configured to generate the laser beam.

19. The laser system according to claim 16 or 17, wherein the laser device comprises a fiber coupling unit configured to output the laser beam to the interconnecting device, and the pulsed laser source is arranged to deliver the laser beam to the fiber coupling unit through free space.

20. The laser system according to any one of claims 16 to 19, further comprising a compressor configured to compress the pulses of the laser beam in time.

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