Selection of laser pulses using an electric shutter

Abstract

Systems and methods are disclosed for selectively enabling or preventing output of laser pulses. In some embodiments, a laser system includes a shutter and a shutter motor configured to move the shutter alternately between a first position in which output of laser electromagnetic radiation is permitted and a second position in which output of laser electromagnetic radiation is prevented.

Description

Technical Field

[0001] The present disclosure is directed to systems and methods for selectively enabling or blocking output of laser pulses.

Background Art

[0002] Lasers are used in many different medical procedures, including many different ophthalmic procedures. For example, lasers may be used in cataract surgery, such as for fragmenting a cataract lens. In some procedures, the laser is used for initial fragmentation of the lens, followed by ultrasonic phacoemulsification of the lens with an ultrasonic handpiece to complete destruction of the lens for removal. In other procedures, the laser may be used for complete fragmentation of the lens for removal or for ultrasonic phacoemulsification without requiring a separate application of ultrasonic energy. Lasers may also be used for other steps in cataract surgery, such as for creating corneal incisions and / or opening the capsule.

[0003] Lasers may also be used in vitreoretinal surgery. In some procedures, lasers may be used for vitrectomy to cut or disrupt vitreous fibers for removal. The laser may be incorporated into a vitrectomy probe, and energy from the laser may be applied to vitreous fibers to cut or disrupt the vitreous fibers for removal.

[0004] In other vitreoretinal applications, lasers may be used for photocoagulation of retinal tissue. Laser photocoagulation may be used to treat conditions such as retinal tears and / or the effects of diabetic retinopathy.

[0005] U.S. Patent Application Publication No. 2018 / 0360657 discloses an example of an ophthalmic laser system. The application describes the use of lasers for purposes such as forming surgical incisions, photodestruction of ocular tissue, and cataract surgery, including laser-assisted cataract surgery (LACS). U.S. Patent Application Publication No. 2019 / 0201238 discloses another example of an ophthalmic laser system. The application describes the use of lasers in vitrectomy probes, etc., for cutting or destroying vitreous fibers. U.S. Patent Application Publication No. 2018 / 0360657 and U.S. Patent Application Publication No. 2019 / 0201238 are expressly incorporated herein by reference in their entirety.

[0006] Some laser systems emit pulses, each with a desired duration and repetition rate. Operating a laser in pulses allows for the achievement of desirable power and energy characteristics for specific applications. In addition, while the energy of the beam emitted by the laser can be controlled by controlling the laser itself, in some systems, it is desirable to control the energy of the laser beam downstream from the laser. Existing systems for laser pulse selection typically have one or more drawbacks, such as power loss, complexity, and cost. Therefore, there is a need for improved systems and methods for laser pulse selection. [Overview of the Initiative] [Problems that the invention aims to solve]

[0007] This disclosure is directed toward improved systems and methods for selectively enabling or blocking the output of laser electromagnetic energy. [Means for solving the problem]

[0008] In some embodiments, the laser system comprises a laser configured to emit electromagnetic radiation and a laser shutter assembly comprising a shutter and a shutter motor. The shutter motor is configured to alternately move the shutter between a first position that allows the electromagnetic radiation emitted by the laser to be output from the laser system and a second position that prevents the electromagnetic radiation emitted by the laser from being output from the laser system. The laser may be configured to emit electromagnetic radiation in pulses.

[0009] In some embodiments, in a first position, the shutter is positioned outside the path of the electromagnetic radiation emitted by the laser, and in a second position, the shutter is positioned within the path of the electromagnetic radiation emitted by the laser.

[0010] In some embodiments, at a first position, the shutter is positioned within the path of electromagnetic radiation emitted by the laser, and at a second position, the shutter is positioned outside the path of electromagnetic radiation emitted by the laser.

[0011] In some embodiments, at a first position, the shutter is positioned in a first orientation within the path of electromagnetic radiation emitted by the laser, and at a second position, the shutter is positioned in a second orientation within the path of electromagnetic radiation emitted by the laser, the second orientation being different from the first orientation.

[0012] In some embodiments, the laser system further comprises an adapted controller that transmits signals to a shutter motor driver to control the movement of the shutter between a first position and a second position.

[0013] In some embodiments, the shutter may include a mirror, and the shutter motor may include a galvanometer motor. The galvanometer motor may be configured to move the mirror between a first position and a second position by rotating the mirror about the mirror axis by a selected angle. The mirror axis and the electromagnetic radiation paths adjacent to the mirror may be skew-line related to each other.

[0014] In some embodiments, the laser system may further include a laser energy control system configured to adjust the amount of electromagnetic energy of each laser pulse leaving the laser system. The laser energy control system may include a waveplate, a waveplate motor, and a polarizer, the waveplate motor configured to move the waveplate to different positions corresponding to different proportions of laser electromagnetic energy permitted to pass through the laser energy control system.

[0015] In some embodiments, a method for controlling a laser system includes emitting electromagnetic radiation from a laser in a path and moving a shutter alternately between a first position where the electromagnetic radiation emitted by the laser is output from the laser system and a second position where the electromagnetic radiation emitted by the laser is not output from the laser system. The electromagnetic radiation may be emitted from the laser in pulses.

[0016] In some embodiments, the method may further include sending a signal from the controller to the shutter motor driver to control the movement of the shutter between a first position and a second position.

[0017] In some embodiments, alternating movement of the shutter between a first position and a second position may include the galvanometer motor causing the mirror to reciprocate between the first position and the second position about the mirror axis.

[0018] In some embodiments, the method may further include moving a waveplate in the path of electromagnetic radiation emitted by the laser to different positions to adjust the amount of electromagnetic energy in each laser pulse leaving the laser system. The different positions of the waveplate may correspond to different proportions of laser electromagnetic energy that are permitted to be output from the laser system.

[0019] Further embodiments and features of the present invention will become apparent from the drawings and the detailed description.

[0020] The accompanying drawings illustrate the implementations of the apparatus and methods disclosed herein and, together with the specification, serve to illustrate the principles of this disclosure. [Brief explanation of the drawing]

[0021] [Figure 1] A schematic diagram of one embodiment of the laser system according to this disclosure is shown, in which the shutter of the laser system is in a first position that allows electromagnetic radiation emitted by the laser to be output from the laser system. [Figure 2] Figure 1 is a schematic diagram of an exemplary laser system, where the shutter of the laser system is in a second position that prevents electromagnetic radiation emitted by the laser from being output from the laser system. [Figure 3] An embodiment of a shutter and shutter motor in a first orientation is shown. [Figure 4] Figure 3 shows the shutter and shutter motor in the second orientation. [Figure 5] A schematic diagram of another embodiment of the laser system according to this disclosure is shown, in which the shutter of the laser system is in a first position that allows electromagnetic radiation emitted by the laser to be output from the laser system. [Figure 6] Figure 5 is a schematic diagram of an exemplary laser system, where the shutter of the laser system is in a second position that prevents electromagnetic radiation emitted by the laser from being output from the laser system. [Figure 7]A schematic diagram of another embodiment of the laser system according to the present disclosure is shown, wherein a shutter of the laser system is in a first position that allows electromagnetic radiation emitted by a laser to be output from the laser system. [Figure 8] It is a schematic diagram of the exemplary laser system of Figure 7, wherein a shutter of the laser system is in a second position that blocks electromagnetic radiation emitted by a laser from being output from the laser system. [Figure 9] A schematic diagram of another embodiment of the laser system according to the present disclosure is shown, wherein a shutter of the laser system is in a first position that allows electromagnetic radiation emitted by a laser to be output from the laser system. [Figure 10] It is a schematic diagram of the exemplary laser system of Figure 9, wherein a shutter of the laser system is in a second position that blocks electromagnetic radiation emitted by a laser from being output from the laser system. [Figure 11] An exemplary shutter control process is shown. DETAILED DESCRIPTION OF EMBODIMENTS

[0022] A better understanding of the accompanying drawings may be obtained by reference to the following detailed description.

[0023] For the purpose of promoting an understanding of the principles of the present disclosure, implementations shown in the drawings are referenced herein, and specific language is used to describe these and other implementations. Nevertheless, it will be understood that no limitation of the scope of the claims is intended by the embodiments illustrated in the drawings or described herein. Any alterations and further modifications to the systems, apparatuses, devices, or methods illustrated or described, as well as any further applications of the principles of the present disclosure, are fully contemplated as would normally occur to one skilled in the art to which the present disclosure pertains. In particular, features, components, and / or steps described with respect to one implementation of the present disclosure may be combined with features, components, and / or steps described with respect to other implementations of the present disclosure. For simplicity, in some cases, the same reference numerals are used throughout the drawings to refer to the same or similar parts.

[0024] As used herein, the designations “First” and “Second” are not intended to indicate or imply any specific location or other characteristic. Rather, when the designations “First” and “Second” are used herein, they are used solely to distinguish one component from the other. Unless direct or indirect mounting, mounting, or joining is specified, the terms “attachment,” “connection,” and “joining” mean attaching, connecting, or joining one component to another, directly or indirectly, via one or more other components.

[0025] Figures 1 and 2 show schematic diagrams of exemplary laser systems 10 according to the present disclosure. Figure 1 shows a laser system 10 having a shutter 22 of the laser system 10 in a first position that allows electromagnetic radiation emitted by a laser 14 to be output from the laser system 10. In this embodiment, in the first position, the shutter 22 is positioned outside the path 15 of electromagnetic radiation emitted by the laser 14. Figure 2 shows a laser system 10 having a shutter 22 of the laser system 10 in a second position that prevents electromagnetic radiation emitted by a laser 14 from being output from the laser system 10. In this embodiment, in the second position, the shutter 22 is positioned within the path 15 of electromagnetic radiation emitted by the laser 14.

[0026] As shown in Figures 1 and 2, the exemplary laser system 10 comprises a laser 14, a laser shutter assembly 20, and an optional laser energy control system 40. Depending on the application, the laser system 10 may also comprise one or more other optical components or other components, if desired. The laser 14 is configured to emit electromagnetic radiation in pulses. During operation, the laser 14 emits laser electromagnetic radiation in pulses along the laser path 15. Allowed by the shutter 22, as described below, the laser electromagnetic energy exits the output of the system 10 and is directed towards a target 80. The target 80 may be another optical component such as an optical fiber, a lens, or other component, or the target 80 may be the final target of the laser energy. For example, the target 80 may be ocular tissue such as a cataract lens, vitreous fibers, retinal tissue, or other tissue.

[0027] In the illustrated embodiment, the laser shutter assembly 20 comprises a shutter 22, a shutter motor 24, and a shutter motor driver 26. The shutter motor 22 is configured to alternately move the shutter 22 between a position shown in Figure 1, where the shutter 22 is positioned outside the path 15 of electromagnetic radiation emitted by the laser 14, and a position shown in Figure 2, where the shutter 22 is positioned within the path 15 of electromagnetic radiation emitted by the laser 14.

[0028] Exemplary assemblies of the shutter motor 24 and shutter 22 are shown in Figures 3 and 4. The shutter motor 24 may be any suitable motor capable of moving the shutter 22 in a desired manner, and the shutter 22 may be any suitable shutter adapted to block or redirect electromagnetic radiation from the laser 14 when the shutter 22 is positioned within the path 15 of electromagnetic radiation emitted by the laser 14.

[0029] In one embodiment, the shutter motor 24 and shutter 22 may be a galbo mirror comprising a galvanometer motor as the shutter motor 24 and a mirror as the shutter 22. Exemplary galbo mirrors that may be used in a laser system such as laser system 10 include galbo mirrors supplied by ScannerMAX, a division of Pangolin Laser Systems, Inc., such as the Compact-506 Galvo, and others.

[0030] A shutter motor 24 (e.g., a galvanometer motor) can rapidly move the shutter 22 (e.g., a mirror) back and forth between a first position and a second position. In the embodiments of Figures 3 and 4, the shutter 22 rotates around the shutter axis 21 over a rotation angle selected by the shutter motor 24. In this embodiment, the shutter axis 21 is offset from the laser path 15. In Figures 3 and 4, the laser path 15 is perpendicular to the plane of the drawing and toward the page of the drawing. In the embodiments of Figures 3 and 4, the shutter (mirror) axis 21 and the electromagnetic radiation path 15 adjacent to the mirror are skew-line related to each other (i.e., they are lines in different planes). The shutter motor 24 (e.g., a galvanometer motor) is capable of moving the shutter 22 (e.g., a mirror) by a selected rotation angle so as to move the mirror between a first position shown in Figure 3, where the shutter 22 is out of the laser energy path 15, and a second position shown in Figure 4, where the shutter 22 is within the laser energy path 15, in the embodiments of Figures 1-2.

[0031] As can be seen in Figure 1, in the laser system 10, when the shutter 22 is in the first position, the shutter 22 is outside the path 15 of the laser electromagnetic radiation and therefore does not obstruct or redirect it. When the shutter 22 is in the first position, the laser electromagnetic radiation can be emitted from the laser system 10 and continue toward the target 80 in the direction indicated by arrow A. The direction indicated by arrow A indicates the direction from the laser 14 to the target 80 and may be a straight line, but does not have to be. For example, in some embodiments, one or more optical components may redirect the laser energy between the laser 14 and the target 80 such that the direction indicated by arrow A is not a straight line.

[0032] As can be seen in Figure 2, in the laser system 10, when the shutter 22 is in the second position, the shutter 22 is in the path 15 of the laser electromagnetic radiation, thereby obstructing or redirecting it. The shutter 22 may absorb and / or reflect the laser electromagnetic radiation. In this embodiment, when the shutter 22 is in the second position, the shutter 22 reflects it in the direction of arrow B to a beam dump 28 designed to absorb and / or diffuse the laser electromagnetic radiation. The direction indicated by arrow B indicates the direction from the laser 14 to the beam dump 28, and, as with the direction indicated by arrow A, may not be a straight line, as one or more optical components may redirect the laser energy between the laser 14 and the beam dump 28. For example, in this embodiment, when the shutter 22 is in the second position, it redirects the laser energy to the beam dump 28. Various beam dumps having features for absorbing and / or diffusing laser electromagnetic energy, e.g., matte black, ridged, metallic, or other properties, are known and available. In some embodiments, the shutter 22 may be designed to absorb and / or diffuse the laser electromagnetic energy with or without the beam damp 28. As can be seen in Figure 2, when the shutter 22 is in the second position, the laser electromagnetic radiation is prevented from being emitted from the laser system 10.

[0033] As shown in Figures 1 and 2, the exemplary laser system 10 may include a laser energy control system 40. The laser energy control system 40 includes a waveplate 42 and a mechanism for moving the waveplate 42. The mechanism for moving the waveplate may include a waveplate motor 54 including a hollow motor shaft 56. The waveplate 42 may be attached to one end of the hollow motor shaft 56, and the waveplate 42 may be attached to the hollow motor shaft 56 using a waveplate adapter 44. The components of the laser energy control system 40 are arranged so that the laser electromagnetic radiation from the laser 14 enters the hollow motor shaft 56 at one end, passes through the hollow motor shaft 56, and then exits through the waveplate 42 at the other end of the hollow motor shaft 56. The laser energy control system 40 further includes a waveplate motor driver 52 for the waveplate motor 54. In operation, the waveplate motor 54 rotates the hollow motor shaft 56 by a desired angular displacement, thereby rotating the waveplate 42 by a desired angular displacement.

[0034] The waveplate 42 works in cooperation with the polarizer 70 to pass or block an amount of laser energy controlled by the rotation of the waveplate 42. The polarized laser energy passes through the waveplate 42, and consequently rotates the polarized laser beam to an angle of 0 to 90 degrees based on the rotational position of the waveplate 42. After passing through the waveplate 42, the laser energy reaches the polarizer 70, which passes through the laser energy polarized in one polarization plane and reflects any laser energy with other polarizations. The laser energy reflected by the polarizer 70 may be directed towards the beam dump 72 in direction C. The direction indicated by arrow C indicates the direction from the polarizer 70 to the beam dump 72, and, as with the directions indicated by arrows A and B, may not be a straight line because one or more optical components may redirect the laser energy between the polarizer 70 and the beam dump 72.

[0035] The operating position of the waveplate 42 may be an incremental position along a 90-degree arc. Up to one side of the arc, the waveplate 42 may change its polarity so that it is rotated by 90 degrees with respect to the polarization allowed by the polarizer 70 (or, in embodiments where the laser electromagnetic radiation is incident on the waveplate 42 which has already been rotated by 90 degrees with respect to the polarization allowed by the polarizer 70, the waveplate 42 may remain without changing its polarity). When laser energy having a polarity oriented at 90 degrees with respect to the polarization allowed by the polarizer 70 strikes the polarizer 70, the polarizer 70 reflects the laser energy. Up to the other side of the arc, the waveplate 42 may change its polarity so that it lies in the same plane as the polarization allowed by the polarizer 70 (or, in embodiments where the laser electromagnetic radiation is incident on the waveplate 42 which lies in the same plane as the polarization allowed by the polarizer 70, the waveplate 42 may remain without changing its polarity). When laser energy having a polarity oriented in the same plane as the polarization allowed by the polarizer 70 strikes the polarizer 70, the polarizer 70 allows the laser energy to pass through. At intermediate angular positions along a 90-degree arc, the waveplate 42 gradually changes the polarity of the laser electromagnetic radiation by being oriented in the same plane as the polarization allowed by the polarizer 70 and by being rotated 90 degrees relative to that plane. Thus, the waveplate 42, when combined with the polarizer 70, allows any portion of the laser energy, from 0% to 100%, to pass to the output of the laser system 10 to the target 80, depending on the angular position of the waveplate 42.

[0036] The exemplary laser system 10 shown in Figures 1 and 2 also includes a controller 60 for controlling the operation of a shutter 22 and, if implemented, a waveplate 42. In the illustrated embodiment, the controller 60 includes a trigger input 62, a control data processor 64, a shutter motor control 66, and a waveplate control 68.

[0037] The trigger input 62 receives a signal regarding the timing of the laser pulse. The control data processor 64 receives input from the system control 18 regarding the desired output for the laser system 10, which is used to control the shutter 22 and, if implemented, the waveplate 42. The control data processor 64 also receives a signal from the trigger input 62 indicating the timing of the laser pulse.

[0038] The system control 18 supplies input to the control data processor 64 based on a desired operating mode, which may be selected by user control or automatic control. For example, the operating mode may be for a certain level of laser energy output that can be controlled by allowing all laser pulses to pass through the system output, not allowing any laser pulses to pass through the system output, or allowing a certain percentage of laser pulses to pass through the system output. For example, the desired level of laser energy output may correspond to allowing one pulse out of 10 pulses, allowing two pulses out of 10 pulses, allowing three pulses out of 10 pulses, etc. In other words, the desired level of laser energy output may correspond to allowing 10%, 20%, 30%, etc., of the laser pulses. The desired level of laser energy output may also correspond to allowing different sequences of laser pulses. For example, the desired level of laser energy output may correspond to a sequence that allows one laser pulse, then disallows one laser pulse, then allows two laser pulses, then disallows one laser pulse, and then repeats this sequence. Many other examples and variations are possible.

[0039] Based on the input from the system control 18 regarding the desired output of the laser system 10 and the signal from the trigger input 62, the control data processor 64 sends a signal to the shutter motor control 66, and then to the shutter motor driver 26 to control the movement of the shutter motor 24 and shutter 22. By controlling the shutter 22, the controller 60 controls whether the laser pulses emitted by the laser proceed to the output of the laser system. This control may be performed for each pulse or once for a group of pulses. In the illustrated embodiment, the control data processor 64 also sends a signal to the waveplate control 68, and then to the waveplate motor driver 52 to control the movement of the waveplate motor 54 and waveplate 42. By controlling the waveplate 42, the controller 60 controls the amount of energy of each laser pulse that proceeds to the output of the laser system.

[0040] In addition to the controller 60, the laser system disclosed herein may include other computer and electrical components known in the art for controlling the system. The computer components may include one or more processors, memory components, and hardware and / or software components.

[0041] Figures 5 and 6 show schematic diagrams of another exemplary laser system 11 according to the present disclosure. Components in Figures 5 and 6 that are the same as those in Figures 1 and 2 are indicated by the same reference numerals. Figure 5 shows the laser system 11 with a shutter 22 of the laser system 11 in a first position that allows electromagnetic radiation emitted by the laser 14 to be output from the laser system 11. Figure 6 shows the laser system 11 with a shutter 22 of the laser system 11 in a second position that prevents electromagnetic radiation emitted by the laser 14 from being output from the laser system 11.

[0042] The laser system 11 in Figures 5 and 6 is similar to the laser system 10 in Figures 1 and 2, except that in the laser system 11, a portion of the laser energy control system 40 is positioned after the laser 14 and before the laser shutter assembly 20. In this embodiment, the waveplate 42, the waveplate motor 54 having a hollow motor shaft 56, and the waveplate adapter 44 are positioned after the laser 14 and before the laser shutter assembly 20. In the illustrated embodiment, the polarizer 70 is positioned after the laser shutter assembly 20, although the polarizer 70 may be positioned before the laser shutter assembly 20. The components of the laser system 11 operate in the same manner as those described above with respect to the laser system 10.

[0043] Figures 7 and 8 show schematic diagrams of another exemplary laser system 12 according to the present disclosure. Components in Figures 7 and 8 that are the same as those in Figures 1 and 2 are indicated by the same reference numerals. Figure 7 shows the laser system 12 with a shutter 22 of the laser system 12 in a first position that allows electromagnetic radiation emitted by the laser 14 to be output from the laser system 12. Figure 8 shows the laser system 12 with a shutter 22 of the laser system 12 in a second position that prevents electromagnetic radiation emitted by the laser 14 from being output from the laser system 12.

[0044] The laser system 12 in Figures 7 and 8 is similar to the laser system 10 in Figures 1 and 2, but differs in that when the shutter is in the first position shown in Figure 7, the shutter 22 is positioned within the path 15 of electromagnetic radiation emitted by the laser 14, so that the shutter reflects the laser energy toward the output of the laser system 12 and the target 80 in the direction indicated by arrow A, and when the shutter 22 is in the second position shown in Figure 8, the shutter 22 is positioned outside the path 15 of electromagnetic radiation emitted by the laser 14, so that the laser energy is directed toward the beam dump 28 in the direction indicated by arrow B.

[0045] In other respects, the laser system 12 is the same as the laser system 10. The laser system 12 comprises a laser 14, a laser shutter assembly 20, and an optional laser energy control system 41. The laser system 12 may also comprise one or more other optical components or other components. In operation, the laser 14 emits laser electromagnetic radiation in pulses along the laser path 15, thereby, when the shutter 22 is in a first position, the laser energy exits the output of the laser system 12 and is directed toward the target 80, and when the shutter 22 is in a second position, no laser energy is output from the laser system 12.

[0046] Similar to laser system 10, the laser shutter assembly 20 in laser system 12 comprises a shutter 22, a shutter motor 24, and a shutter motor driver 26. The shutter motor 22 is configured to alternately move the shutter 22 between a first position shown in Figure 7 and a second position shown in Figure 8. Laser system 12 may use a shutter motor 24 and shutter 22 similar to those described above with respect to laser system 10, including the shutter motor 24 and shutter 22 assembly shown in Figures 3 and 4.

[0047] The laser system 12 may have a laser energy control system similar to the laser energy control system 40 described above with respect to the laser system 10. Alternative laser energy control systems 41 that may be used in embodiments of other laser systems described herein are shown in Figures 7 and 8.

[0048] The laser energy control system 41 comprises a waveplate 42 and a mechanism for moving the waveplate 42. The mechanism for moving the waveplate 42 may comprise a waveplate motor 54, gears or pulleys 48, and a belt 46. The laser energy control system 41 further comprises a waveplate motor driver 52 for the waveplate motor 54. The belt 46 extends around the gears or pulleys 48 and the waveplate 42 (or the carriage supporting the waveplate 42) such that the rotation of the gears or pulleys 48 by the waveplate motor 54 drives the rotation of the waveplate 42. The waveplate motor 54 may be a stepping motor, but other suitable motors such as voice coils and other motors may be used. In operation, the waveplate motor 54 drives the gears or pulleys 48, which then drive the belt 46, thereby rotating the waveplate 42 by a desired angular displacement.

[0049] The waveplate 42, in a manner similar to that described above with respect to the laser energy control system 40, cooperates with the polarizer 70 to pass or block an amount of laser energy controlled by the rotation of the waveplate 42. The waveplate 42, in combination with the polarizer 70, allows any amount between 0% and 100% of the laser energy to pass to the output of the laser system 12 to the target 80, depending on the angular position of the waveplate 42. The laser energy reflected by the polarizer 70 may be directed towards the beam dump 72 in direction C, as shown in Figure 7.

[0050] The laser system 12 may have a controller 60 similar to the controller described above for the laser system 10. The controller 60 comprises a trigger input 62, a control data processor 64, a shutter motor control 66, and a waveplate control 68, all operating in the same manner as described above. One difference in the laser system 12 compared to the laser system 10 is that when it is necessary to prevent the laser pulse from proceeding to the output of the laser system 12, the controller 60 sends a signal via the shutter motor control 66 to move the shutter out of the laser path, as shown in Figure 8, and when it is necessary to allow the laser pulse to proceed to the output of the laser system 12, the controller 60 sends a signal via the shutter motor control 66 to move the shutter back into the laser path, as shown in Figure 7.

[0051] In alternative embodiments, as described above with respect to Figures 5 and 6, all or part of the laser energy control system 41 within the laser system 12 may be positioned after the laser 14 and before the laser shutter assembly 20. For example, the waveplate 42, waveplate motor 54, gear or pulley 48, and belt 46 may be positioned after the laser 14 and before the laser shutter assembly 20. In addition, the polarizer 70 may be positioned before or after the laser shutter assembly 20.

[0052] Figures 9 and 10 show schematic diagrams of another exemplary laser system 13 according to the present disclosure. Components in Figures 9 and 10 that are the same as those in Figures 1 and 2 are indicated by the same reference numerals. Figure 9 shows the laser system 13 with a shutter 22 in a first position that allows electromagnetic radiation emitted by the laser 14 to be output from the laser system 13 and reflected by the shutter 22 and an optional mirror 27. Figure 10 shows the laser system 13 with a shutter 22 in a second position that prevents electromagnetic radiation emitted by the laser 14 from being output from the laser system 13 and reflected by the shutter 22 to a beam dump 28.

[0053] The laser system 13 in Figures 9 and 10 is similar to the laser system 10 in Figures 1 and 2, except that the shutter in the laser system 13 is positioned such that when the shutter is in the first position shown in Figure 9, the shutter 22 is positioned within the path 15 of electromagnetic radiation emitted by the laser 14, and the shutter reflects the laser energy toward the output of the laser system 11 and the target 80 in the direction indicated by arrow A; and when the shutter 22 is in the second position shown in Figure 10, the shutter 22 is also positioned within the path 15 of electromagnetic radiation emitted by the laser 14, but in a different orientation, so that the shutter 22 reflects the laser energy toward the beam dump 28 in the direction indicated by arrow B.

[0054] In other respects, laser system 13 is the same as laser system 10. Laser system 13 comprises a laser 14, a laser shutter assembly 20, and an optional laser energy control system 40. Laser system 13 may also comprise one or more other optical components or other components. In operation, laser 14 emits laser electromagnetic radiation in pulses along the laser path 15, thereby, when the shutter 22 is in a first position, the laser energy exits the output of laser system 13 and is directed toward the target 80, and when the shutter 22 is in a second position, no laser energy is output from laser system 13.

[0055] Similar to laser system 10, the laser shutter assembly 20 in laser system 13 comprises a shutter 22, a shutter motor 24, and a shutter motor driver 26. The shutter motor 22 is configured to alternately move the shutter 22 between a first position shown in Figure 9 and a second position shown in Figure 10. Laser system 13 may use a shutter motor 24 and shutter 22 similar to those described above with respect to laser system 10, including the shutter motor 24 and shutter 22 assembly shown in Figures 3 and 4.

[0056] Laser system 13 may have a laser energy control system similar to the laser energy control system 40 described above with respect to laser system 10. Similar to laser systems 10 and 11, laser system 13 may use a laser energy control system such as the laser energy control system 41 shown in Figures 7 and 8.

[0057] The laser system 13 may have a controller 60 similar to the controller described above for the laser system 10. The controller 60 comprises a trigger input 62, a control data processor 64, a shutter motor control 66, and a waveplate control 68, all operating in the same manner as described above. One difference in the laser system 13 compared to the laser system 10 is that when it is necessary to allow the laser pulse to proceed to the output of the laser system 13, the controller 60 sends a signal via the shutter motor control 66 to place the shutter 22 in the laser path into a first orientation, as shown in Figure 9, and when it is necessary to prevent the laser pulse from proceeding to the output of the laser system 13, the controller 60 sends a signal via the shutter motor control 66 to place the shutter 22 in the laser path into a second orientation, as shown in Figure 10, where the second orientation is different from the first orientation.

[0058] In alternative embodiments, as described above with respect to Figures 5 and 6, all or part of the laser energy control system 40 within the laser system 13 may be positioned behind the laser 14 and before the laser shutter assembly 20. For example, the waveplate 42, the waveplate motor 54 having a hollow motor shaft 56, and the waveplate adapter 44 may be positioned behind the laser 14 and before the laser shutter assembly 20. In addition, the polarizer 70 may be positioned before or after the laser shutter assembly 20.

[0059] Figure 11 shows an exemplary shutter control process that may be used with laser systems such as laser system 10, laser system 11, and laser system 13 disclosed herein. Based on the operation of laser 14, a signal as shown in S1 of Figure 11 is sent to the trigger input 62 of controller 60 prior to each laser pulse emitted by laser 14. For example, if laser 14 is operating at 1 kHz (1000 laser pulses per second), the laser pulse trigger signal 101 is sent to the trigger input 62 of controller 60 prior to each laser pulse at a frequency of 1 kHz. In another embodiment, if laser 14 is operating at 900 Hz (900 laser pulses per second), the laser pulse trigger signal 101 is sent to the trigger input 62 of controller 60 prior to each laser pulse at a frequency of 900 Hz. Many other modifications are possible. The laser may emit pulses at any frequency suitable for a particular application, and the frequency may be switched during operation.

[0060] The control data processor 64 receives a signal from the trigger input 62 indicating the timing of the laser pulse based on the laser pulse trigger signal 101. Based on the signal from the trigger input 62 and the input from the system control 18 regarding the desired output to the laser system, the control data processor 64 sends a signal to the shutter motor control 66, and then a signal to the shutter motor driver 26 to control the movement of the shutter motor 24 and the shutter 22. An example of a signal sent from the shutter motor control 66 to the shutter motor driver 26 is shown in S2 of Figure 11. Signal 121 causes the shutter motor 24 to move the shutter 22 to a first position of the shutter 22, for example, as shown in Figures 1, 5, 7, or 9, which allows the laser energy to continue to be directed toward the target 80 and the output of the laser system. Signal 122 causes the shutter motor 24 to move the shutter 22 to a second position of the shutter 22, such as shown in Figures 2, 6, 8, or 10, where the shutter position prevents the laser energy from continuing into the output of the laser system toward the target 80.

[0061] The timing of the laser pulses emitted by laser 14 is shown in L1 of Figure 11. As shown in L1, each laser pulse 111 is emitted by laser 14 immediately after each laser pulse trigger signal 101 is sent to the trigger input 62 of controller 60. The position of shutter 22 determines whether each laser pulse 111 reaches the output of the laser system.

[0062] The laser pulse 131 that reaches the output of the laser system is shown in L2 in Figure 11. If the shutter 22 is positioned so as to allow the laser energy to be directed towards the output of the laser system, i.e., after signal 121 but before signal 122, the laser pulse is allowed to exit the laser system indicated by the laser pulse 131. If the shutter 22 is positioned so as not to allow the laser energy to be directed towards the output of the laser system, i.e., after signal 122 but before signal 121, the laser pulse is not allowed to exit the laser system, as indicated by the space 132 in which the laser pulse 111 present in L1 is not present in L2.

[0063] Since the shutter motor 24 can quickly move the shutter 22 between a first position and a second position, the laser system may selectively allow pulses from the laser to reach the system output pulse by pulse. The laser system may also allow a group of laser pulses to reach the system output at once, or it may prevent a group of laser pulses from reaching the system output at once.

[0064] In some embodiments, the laser system described herein may be used for cataract surgery. In some embodiments, the output energy of the laser system may be used for cataract lens lithotripsy or phacoemulsification. In some embodiments, the laser output is used for initial cataract lens lithotripsy, followed by phacoemulsification of the lens using an ultrasonic handpiece to complete the destruction of the lens for excision. In other embodiments, the laser output may be used for lens lithotripsy or phacoemulsification to a degree sufficient for lens excision without requiring the separate application of ultrasonic energy. Additionally or alternatively, the laser output may be suitable for making a corneal incision and / or opening the lens capsule.

[0065] In other embodiments, the laser system may be suitable for retinal and vitreous surgery. In some embodiments, the output energy of the laser system may be suitable for cutting or destroying vitreous fibers for excision. In other retinal and vitreous applications, the laser output may be suitable for ocular tissue treatment, such as photocoagulation of retinal tissue, to treat problems such as retinal tears and / or the effects of diabetic retinopathy.

[0066] In one embodiment, the laser operates in the infrared region. For example, the laser may emit electromagnetic radiation in the mid-infrared region, for example, in a wavelength range of about 2.0 microns to about 4.0 microns. Some exemplary wavelengths include about 2.5 microns to 3.5 microns, for example, about 2.7 microns, about 2.75 microns, about 2.8 microns, or about 3.0 microns. Such a laser may be suitable, for example, for lens lithotripsy in cataract surgery or other procedures. In another embodiment, the laser emits electromagnetic radiation in the ultraviolet region. In yet another embodiment, the laser emits electromagnetic radiation in the visible region.

[0067] The ability to selectively output laser pulses and / or control laser output energy is useful in procedures where laser control is advantageous. For example, in cataract surgery, it may be desirable to operate the laser system at high power to initially destroy the lens, but then at lower power to destroy smaller fragments. Controlling the number of laser pulses and / or the pulse energy level allows for the application of the correct level of force to smaller particles that might otherwise be swept away before being drawn out of the eye by the handpiece's perfusion system.

[0068] As those skilled in the art will understand, the systems and methods disclosed herein have advantages over conventional systems and methods. For example, in some conventional systems and methods, selecting pulses may require a large amount of power and may result in undesirable losses of laser power. The Pockels cell system uses a crystal to rotate the polarity of a laser beam by applying a high voltage to the crystal. The high voltage can vary from 0 to 6.5 kV based on the required amount of polarity rotation. In contrast, the systems and methods described herein allow for the selection of laser pulses that do not result in undesirable losses of laser power due to low power usage, or that are essentially absent. Furthermore, the cost of the systems described herein may be substantially lower than certain other systems. Also, in some embodiments, high voltage is not required, improving the electromagnetic compatibility of the system.

[0069] Those skilled in the art will correctly recognize that the embodiments contained herein are not limited to the specific exemplary embodiments described above. While exemplary embodiments have been illustrated and described, a wide range of modifications, alterations, and substitutions are possible in the foregoing disclosure. It should be understood that such modifications may be made to the foregoing without departing from the scope of this disclosure. Accordingly, it is appropriate that the appended claims be interpreted broadly and in accordance with this disclosure.

Claims

1. It is a laser system, A laser configured to emit electromagnetic radiation in pulses, A laser shutter assembly comprising a shutter and a shutter motor, Controller and The laser system comprises a laser energy control system configured to adjust the amount of electromagnetic energy of each laser pulse emitted from the laser system, The shutter comprises a mirror, and the shutter motor comprises a galvanometer motor controlled by a shutter motor driver. The shutter motor is configured to alternately move the shutter between a first position that allows electromagnetic radiation emitted by the laser to be output from the laser system and a second position that prevents electromagnetic radiation emitted by the laser from being output from the laser system. The galvanometer motor is configured to move the mirror between the first position and the second position by rotating the mirror around the mirror axis by a selected angle. The controller selectively enables the output of the laser pulse from the laser system by transmitting a signal to the shutter motor driver to control the movement of the mirror between the first position and the second position with each pulse. The laser energy control system is Waveplate and, Waveplate motor and, Equipped with a polarizing plate, A laser system in which the waveplate motor is configured to move the waveplate to different positions corresponding to different proportions of laser electromagnetic energy permitted to pass through the laser energy control system.

2. The laser system according to claim 1, wherein, in the first position, the shutter is positioned within the path of the electromagnetic radiation emitted by the laser, and in the second position, the shutter is positioned outside the path of the electromagnetic radiation emitted by the laser.

3. The laser system according to claim 1, wherein, at the first position, the shutter is positioned in a first orientation within the path of the electromagnetic radiation emitted by the laser, and at the second position, the shutter is positioned in a second orientation within the path of the electromagnetic radiation emitted by the laser, the second orientation being different from the first orientation.

4. The laser system according to claim 1, wherein the mirror axis and the electromagnetic radiation path adjacent to the mirror are in a skew line relationship with respect to each other.

5. A method for operating a laser system, The controller causes the lasers in the path to emit pulsed electromagnetic radiation, The controller alternately moves the shutter between a first position where electromagnetic radiation emitted by the laser is output from the laser system and a second position where electromagnetic radiation emitted by the laser is not output from the laser system. The controller transmits a signal from the controller to the shutter motor driver to control the movement of the shutter between the first position and the second position with each pulse, The controller includes moving the waveplates in the path of the electromagnetic radiation emitted by the laser to different positions in order to adjust the amount of electromagnetic energy of each laser pulse leaving the laser system, The shutter comprises a mirror, and the shutter motor comprises a galvanometer motor controlled by a shutter motor driver. The step of moving the shutter alternately between the first position and the second position includes the galvanometer motor causing the mirror to reciprocate between the first position and the second position about the mirror axis, A method of operating a laser system, wherein the different positions on the waveplate correspond to different proportions of the laser electromagnetic energy permitted to be output from the laser system.

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