Device and method for quickly positioning vertex of contact lens of femtosecond laser surgical equipment

Abstract

The invention discloses a device and a method for quickly positioning the vertex of a contact lens of femtosecond laser surgical equipment, belongs to the field of medical instruments, adopts automatic calibration, can control the laser energy, the beam position and the laser focus position, and can determine the vertex position of the contact lens based on the focusing position of reflected light and the energy of the reflected light. And compared with the existing manual debugging mode, the calibration precision and speed are greatly improved.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, and particularly to a device and method for quickly positioning the vertex of a contact lens for a femtosecond laser surgical device. Background Art

[0002] Femtosecond laser surgery precisely cuts corneal tissue through femtosecond laser. Since it does not require a traditional scalpel, it realizes a bladeless surgical process, improves the accuracy and safety of the surgery, reduces the risk of surgical trauma and complications, and has developed rapidly in clinical ophthalmology. Femtosecond laser surgery relies on the vertex of the contact lens as a reference for the corneal surface, providing a depth positioning reference for intraoperative laser scanning. During the preoperative system detection stage, vertex positioning needs to be completed without the contact lens being adsorbed to the eyeball. However, the existing technologies have the following pain points: speed bottleneck, traditional manual adjustment or single-modal detection takes a long time (>5 minutes), affecting the surgical efficiency; accuracy depends on manual experience, and manually aligning the contact lens with the optical center is likely to introduce errors (±0.2 mm). Summary of the Invention

[0003] The present invention provides a device and method for quickly positioning the vertex of a contact lens for a femtosecond laser surgical device, which can solve the problems of long time consumption and easy introduction of errors existing in the manual adjustment of the vertex positioning of the contact lens in the prior art.

[0004] A device for quickly positioning the vertex of a contact lens for a femtosecond laser surgical device includes:

[0005] A femtosecond laser for emitting a femtosecond pulsed laser beam;

[0006] A beam scanning component for positioning and focusing the laser beam and controlling the position of the laser beam focus;

[0007] A reflection confocal detection component for adjusting the focusing position of the reflected light and detecting the energy of the reflected light; and

[0008] A data analysis and processing component, which is communicatively connected to the beam scanning component and the reflection confocal detection component;

[0009] The data analysis and processing component moves the laser focus to a specified position based on the beam scanning component and collects the energy of the reflected light, and determines the position of the contact lens vertex based on the energy of the reflected light.

[0010] Preferably, it further includes a beam control component communicatively connected to the data analysis and processing component, and the beam control component is used to realize the control of the laser beam transmission path and energy control.

[0011] Preferably, the beam control component includes an optical energy controller and a beam pointing stabilizer. Among them, the optical energy controller includes an optical power attenuator and an energy detector. The energy detector is used to detect the optical pulse energy value under the contact lens. The beam pointing stabilizer includes a pair of piezoelectric mirrors and a beam position detector.

[0012] Preferably, the optical power attenuator includes a half-wave plate and a polarization beam splitter prism;

[0013] The half-wave plate is installed on an electric rotary displacement stage, and the electric rotary displacement stage can drive the half-wave plate to rotate, thereby adjusting the transmitted light energy of the polarization beam splitter prism.

[0014] Preferably, the piezoelectric mirror has a dielectric film high-reflection mirror. The two piezoelectric mirrors can confine the beam in the position of the X / Y plane, and the beam position detector is used to detect the position of the beam.

[0015] Preferably, the beam scanning component includes an X / Y scanner, a Z scanner, and an objective lens;

[0016] Among them, the X / Y scanner includes a scanning motor and a detector. A mirror is installed on the scanning motor. The Z-axis scanner includes a pair of achromatic doublet lens groups, and one of the doublet lenses is installed on a single-axis displacement stage.

[0017] Preferably, the reflection confocal detection component includes a lens group, a precision pinhole, and a photodetector;

[0018] Among them, the lens group is used to focus the reflected beam, and it includes a pair of achromatic doublet lenses;

[0019] The precision pinhole is located in front of the photodetector. The precision pinhole is the focus of the reflected light and can be conjugate with the focus on the contact lens to form a confocal system.

[0020] Preferably, it further includes a vacuum negative pressure generating component, which includes a negative pressure sensor, a solenoid valve, and a vacuum pump.

[0021] Preferably, the data analysis and processing component includes an FPGA processor, an ARM processor, and an AD / DA module, and further includes:

[0022] A laser energy acquisition unit, a quadrant signal acquisition unit, a confocal detector energy acquisition unit, an X / Y scanner control unit, and a Z scanner control unit with the FPGA processor as the core; and

[0023] A laser energy analysis and control unit, a beam position analysis and control unit, and a confocal adjustment and confocal position analysis and control unit with the ARM processor as the core;

[0024] Among them, the FPGA processor is communicatively connected to the ARM processor;

[0025] The laser energy acquisition unit and the quadrant signal acquisition unit are communicatively connected to the beam control component through an ADC;

[0026] The X / Y scanner control unit and the Z scanner control unit are communicatively connected to the beam scanning component through an ADC;

[0027] The confocal detector energy acquisition unit is communicatively connected to the reflection confocal detection component through an ADC;

[0028] The laser energy analysis and control unit determines whether the energy meets the setting according to the laser energy value collected by the laser energy acquisition unit and can regulate the laser power;

[0029] The beam position analysis and control unit determines whether the beam position meets the setting according to the data collected by the quadrant signal acquisition unit and can regulate the position of the beam in the X / Y plane;

[0030] The confocal adjustment and confocal position analysis and control unit determines whether the reflection light focusing position is conjugate to the focus on the contact lens according to the laser energy value collected by the confocal detector energy acquisition unit. When the foci are conjugate, the position of the Z-axis scanner is obtained.

[0031] A method for quickly positioning the vertex of a contact lens for a femtosecond laser surgical device includes the following steps:

[0032] a) Install the contact lens, turn on the solenoid valve to generate negative pressure, and ensure the contact lens is properly installed according to the negative pressure value detected by the negative pressure sensor;

[0033] b) The femtosecond laser emits a pulsed laser beam, the beam is transmitted to the beam control component, the beam control component detects the laser energy and position information, and transmits the information to the data analysis and processing component for beam position and output port energy adjustment;

[0034] c) The beam is transmitted to the beam scanning component, the objective lens focuses the beam, and the X / X scanner controls the focus on the contact lens dot;

[0035] d) The reflected light is transmitted to the reflection confocal detection component, the lens group focuses the reflected beam, and the precision aperture adjusts the position so that the focusing focus is at the center of the aperture;

[0036] e) Control the Z scanner to move from a position far from the output port towards the main optical path transmission direction, and at the same time, the confocal photodetector records the reflected light energy for each step the Z scanner moves;

[0037] f) Collect the energy information, fit the "Z scanner position - reflected light energy" curve, and find the Z scanner position corresponding to the maximum energy after smoothing processing;

[0038] g) Control the Z scanner to move to the position where the reflected energy is maximum. At this time, the light beam is focused on the vertex of the contact lens.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention adopts automatic calibration, which can realize the control of the laser energy, the beam position, and the laser focus position, and can determine the vertex position of the contact lens based on the focusing position and energy of the reflected light, greatly improving the calibration accuracy and speed compared with the existing manual debugging method. Description of the Drawings

[0040] Figure 1 It is a schematic structural diagram of a device for quickly positioning the vertex of a contact lens;

[0041] Figure 2 It is a working flowchart of a method for quickly positioning the vertex of a contact lens.

[0042] Description of the Reference Numerals:

[0043] 10 - femtosecond laser, 20 - beam control component, 22 - electric rotary displacement stage, 25 - half-wave plate, 28 - beam position detector, 29 - energy detector, 40 - reflection confocal detection component, 43 - quarter-wave plate, 46 - lens group, 47 - precision pinhole, 48 - photodetector, 50 - beam scanning component, 51 - Z scanner, 52 - X scanner, 53 - Y scanner, 54 - objective lens, 60 - contact lens, 70 - vacuum negative pressure generating component, 80 - data analysis and processing component, 82 - laser energy acquisition unit, 81 - quadrant signal acquisition unit, 83 - confocal detector energy acquisition unit. Detailed Embodiments

[0044] Next, with reference to the drawings, a specific embodiment of the present invention will be described in detail. However, it should be understood that the protection scope of the present invention is not limited by the specific embodiments.

[0045] As Figure 1 shown, the device for quickly positioning the vertex of the contact lens 60 provided in the embodiment of the present invention includes a femtosecond laser 10, a beam control component 20, a reflection confocal detection component 40, a beam scanning component 50, a vacuum negative pressure generating component 70, and a data analysis and processing component 80;

[0046] The femtosecond laser 10 is used to emit a femtosecond pulsed laser beam;

[0047] The beam control component 20 is used for controlling the laser beam transmission path and energy;

[0048] The reflection confocal detection component 40 is used for adjusting the confocal position of the reflected light and detecting the energy of the reflected light; the beam scanning component 50 is used for controlling the focus position of the laser beam;

[0049] The vacuum negative pressure generating component 70 is used to provide a certain degree of negative pressure to maintain the effective fixation of the contact lens 60 and the objective lens 54;

[0050] The data analysis and processing component 80 is used to collect laser energy, analyze whether the energy magnitude meets the set requirements, and control the beam control component 20 to adjust the laser energy. It is also used to collect laser position information, analyze whether the laser position is located at the center of the optical path, and control the beam control component 20 to adjust the beam position. It is also used to control the beam scanning component 50 to move the laser focus to a specified position under the control of the beam scanning component 50. It is also used to control the reflection light focusing position and collect the reflection light energy, and analyze the reflection light energy to determine the vertex position of the contact lens 60 (the vertex position of the contact lens 60 is the Figure 1 black dot position of the contact lens 60 in

[0051] The beam control component 20 includes an optical energy controller and a beam pointing stabilizer. Among them, the optical energy controller includes an optical power attenuator and an energy detector 29. The optical power attenuator includes a half-wave plate 25 and a polarization beam splitter prism. The half-wave plate 25 is installed on an electric rotary displacement stage 22. The electric rotary displacement stage can drive the half-wave plate 25 to rotate, thereby adjusting the transmitted light energy of the polarization beam splitter prism, that is, controlling the energy ratio in the main optical path and the detection optical path. In addition, it also includes a fixed polarization beam splitter prism for controlling the energy ratio of the beam in the horizontal and vertical transmission directions to be 1:1;

[0052] The energy detector 29 is used to detect the laser pulse energy. There is a linear relationship between the energy sampling value of the energy detector 29 and the deflection angle of the electric rotary displacement stage 22, and there is a linear relationship between the energy sampling value of the energy detector 29 and the laser energy at the light outlet of the objective lens 54. Therefore, by adjusting the deflection angle of the electric rotary displacement stage 22, the energy control at the light outlet of the objective lens 54 can be achieved;

[0053] The beam pointing stabilizer includes a pair of piezoelectric mirrors and a beam position detector 28. The pair of piezoelectric mirrors is used to adjust the position of the beam in the X / Y plane, and the beam position detector 28 is used to detect the position of the beam in the X / Y plane. The two form a closed-loop control for regulating the correct position of the beam in the X / Y plane;

[0054] The beam scanning component 50 includes an X / Y scanner 53 (X scanner 52, Y scanner 53) composed of a galvanometer-based scanning motor and a detector, and also includes an axial focus displacement component, that is, a Z scanner 51, composed of a pair of confocal achromatic doublet lens groups 46 and one of the doublet lenses is fixed on a single-axis high-precision displacement stage, and also includes an objective lens 54 for beam focusing;

[0055] The X scanner 52 and the Y scanner 53 control the laser focus at the dot position of the contact lens 60, and the Z scanner 51 controls the laser focus to move along the optical axis direction. In addition, the objective lens 54 is used to focus the laser beam, and the size of the focused spot is 3 um;

[0056] The X / Y scanner 53 includes a mirror mounted on a scanning motor, and the detector provides position feedback;

[0057] When the Z scanner 51 drives a doublet lens to move on a single-axis high-precision displacement stage, it controls the laser focus to move along the optical axis direction;

[0058] The reflection confocal detection component 40 includes a lens group 46 composed of a pair of achromatic doublet lens groups 46, and also includes a precision pinhole 47 with a movable position placed on the focal plane of the lens, and also includes a photodetector 48;

[0059] The polarization beam splitting prism and the quarter-wave plate 43 are used in cooperation to make all the reflected light pass through two reflectors to the lens group 46;

[0060] All four in this embodiment are used to realize the adjustment of the optical path transmission direction;

[0061] The lens group 46 is used to focus the reflected light beam on the precision pinhole 47;

[0062] The precision pinhole 47 is located in front of the detector. The excitation light is focused on the surface of the contact lens. The precision pinhole 47 is the focus of the reflected light, conjugate to the focus on the contact lens, forming a confocal system;

[0063] The photodetector 48 is used to receive the optical signal passing through the pinhole and convert it into an electrical signal;

[0064] The data analysis and processing component 80 of this embodiment specifically includes an FPGA, an ARM processor and its external memory, and an ad / da module. Among them, the FPGA processor is the core, including a laser energy acquisition unit 82, a quadrant signal acquisition unit 81, a confocal detector energy acquisition unit 83, an X / Y scanner 53 control unit, and a Z scanner 51 control unit; among them, the ARM processor is the core, including a laser energy analysis and control unit, a beam position analysis and control unit, and a confocal adjustment and confocal position analysis and control unit. Among them, the FPGA and the ARM are connected by an AXI interface for communication.

[0065] The laser energy acquisition unit 82 is connected to the energy detector 29 through ADC, and the ADC is connected to the FPGA through the JESD204B interface. The FPGA transmits the sampled values to the ARM through the AXI interface.

[0066] The four-quadrant signal acquisition unit 81, ADC is connected to the four-quadrant sensor, and the ADC is connected to the FPGA using an SPI interface. The FPGA transmits the four-quadrant sampling value to the ARM via an AXI interface.

[0067] The confocal detector energy collection unit 83, ADC is connected to the photodetector 48, and the ADC is connected to the FPGA using an SPI interface. The FPGA collects the confocal energy and performs data smoothing, and transmits it to the ARM-side external DDR4 memory through the AXI interface.

[0068] The X / Y scanner 53 controls the unit, the ADC is connected to the position detector by communication, and the ADC is connected to the FPGA by an SPI interface; the DAC is connected to the scanning motor by communication, and the DAC is connected to the FPGA by an SPI interface. The FPGA sends control data to drive the X / Y scanner 53 to control the light beam in the center of the optical path, and collects feedback from the position detector to determine that the control position is correct.

[0069] The Z scanner 51 control unit, the FPGA uses a calibrated interface to communicate with the Z scanner 51 driver, and controls the Z scanner 51 to move in the axial direction of the optical path with a stepping precision of 50nm.

[0070] The laser energy analysis control unit, ARM, determines that the energy value meets the setting according to the laser energy value collected by the energy detector 29, and can control the electric rotary translation stage 22 through the USB interface to adjust the optical power.

[0071] The beam position analysis control unit, ARM, determines that the beam position meets the settings based on the 4Q data collected by the four-quadrant sensor. At the same time, it can control a pair of piezoelectric mirrors through the USB interface to adjust the position of the beam in the X / Y plane.

[0072] Confocal adjustment and confocal position analysis control unit, ARM determines whether the pinhole position is located at the focus of the lens group 46 according to the laser energy value collected by the photodetector 48, and at the same time, the position of the precision pinhole 47 in the focal plane of the lens group 46 can be controlled through the USB interface. Secondly, the laser energy value is fitted to the confocal curve, the position of the Z scanner 51 at the time of confocal is found, and the Z scanner 51 is controlled to move to the position where the reflected energy is the maximum, and the light beam is focused on the vertex of the contact lens 60.

[0073] Embodiment 2

[0074] like Figure 2 As shown, this embodiment proposes a method for quickly locating the vertex of a contact lens of a femtosecond laser surgical device based on the first embodiment, comprising the following steps:

[0075] a) Install the contact lens, open the solenoid valve to generate negative pressure, and detect the negative pressure value according to the negative pressure sensor to ensure that the contact lens is installed properly;

[0076] b) The femtosecond laser emits a pulsed laser beam, which is transmitted to the beam control component. The beam control component detects the laser energy and position information and transmits the information to the data analysis and processing component for adjusting the beam position and the energy at the light output port.

[0077] c) The beam is transmitted to the beam scanning component, and the objective lens focuses the beam. The X / X scanner controls the focus at the contact lens dot.

[0078] d) The reflected light is transmitted to the reflection confocal detection component. The lens group focuses the reflected beam, and the precision aperture adjusts the position so that the focused point is at the center of the aperture.

[0079] e) Control the Z scanner to move from a position far away from the light output port towards the main optical path transmission direction. At the same time, the confocal photodetector records the reflected light energy when the Z scanner moves one step each time.

[0080] f) Collect the energy information, fit the "Z scanner position - reflected light energy" curve, and find the position of the Z scanner corresponding to the maximum energy after smoothing processing.

[0081] g) Control the Z scanner to move to the position where the reflected energy is maximum. At this time, the beam is focused on the vertex of the contact lens.

[0082] For those skilled in the art, it is obvious that the present invention is not limited to the details of the above - mentioned exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit and basic features of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non - restrictive. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the present invention. Any reference signs in the claims should not be regarded as limiting the claimed rights.

[0083] In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only contains an independent technical solution. This narrative way of the specification is only for clarity. Those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A device for quickly positioning the vertex of a contact lens in a femtosecond laser surgery device, characterized in that, Comprising: A femtosecond laser for emitting a femtosecond pulsed laser beam; A beam scanning component for laser beam positioning and focusing and controlling the focal position of the laser beam; A reflection confocal detection component for adjusting the focal position of the reflected light and detecting the energy of the reflected light; and A data analysis and processing component, the data analysis and processing component being communicatively connected to the beam scanning component and the reflection confocal detection component; The data analysis and processing component moves the laser focus to a specified position based on the beam scanning component and collects the reflected light energy, and determines the vertex position of the contact lens based on the reflected light energy.

2. The vertex rapid positioning device for a femtosecond laser surgical device contact lens according to claim 1, wherein It further includes a beam control component communicatively connected to the data analysis and processing component, the beam control component being used to achieve control of the laser beam transmission path and energy control.

3. The vertex rapid positioning device for a femtosecond laser surgical device contact lens according to claim 2, characterized in that, The beam control component includes an optical energy controller and a beam pointing stabilizer. Among them, the optical energy controller includes an optical power attenuator and an energy detector. The energy detector is used to detect the optical pulse energy value under the contact lens. The beam pointing stabilizer includes a pair of piezoelectric mirrors and a beam position detector.

4. The vertex rapid positioning device for a femtosecond laser surgical device contact lens according to claim 3, characterized in that, The optical power attenuator includes a half-wave plate and a polarization beam splitter prism; The half-wave plate is mounted on an electric rotary displacement stage, and the electric rotary displacement stage can drive the half-wave plate to rotate, thereby adjusting the transmitted light energy of the polarization beam splitter prism.

5. The vertex rapid positioning device for a femtosecond laser surgical device contact lens according to claim 3, characterized in that, The piezoelectric mirror has a dielectric film high-reflection mirror. The two piezoelectric mirrors can confine the beam in the X / Y plane position, and the beam position detector is used to detect the position of the beam.

6. The vertex rapid positioning device for a femtosecond laser surgical device contact lens according to claim 1, characterized in that, The beam scanning component includes an X / Y scanner, a Z scanner, and an objective lens; Among them, the X / Y scanner includes a scanning motor and a detector. A mirror is mounted on the scanning motor. The Z-axis scanner includes a pair of achromatic doublet lens groups, and one of the doublet lenses is mounted on a single-axis displacement stage.

7. The vertex rapid positioning device for a femtosecond laser surgery device contact lens according to claim 1, characterized in that, The reflection confocal detection component includes a lens group, a precision pinhole, and a photodetector; Among them, the lens group is used to focus the reflected beam, and it includes a pair of achromatic doublet lenses; The precision pinhole is located in front of the photodetector. The precision pinhole is the focus of the reflected light and can be conjugate to the focus on the contact lens to form a confocal system.

8. The vertex rapid positioning device for a femtosecond laser surgery device contact lens according to claim 1, characterized in that, It further includes a vacuum negative pressure generating component, which includes a negative pressure sensor, a solenoid valve, and a vacuum pump.

9. The vertex rapid positioning device for a femtosecond laser surgical device contact lens according to claim 1, characterized in that, The data analysis and processing component includes an FPGA processor, an ARM processor, and an AD / DA module, and further includes: A laser energy acquisition unit, a quadrant signal acquisition unit, a confocal detector energy acquisition unit, an X / Y scanner control unit, and a Z scanner control unit with the FPGA processor as the core; and A laser energy analysis and control unit, a beam position analysis and control unit, and a confocal adjustment and confocal position analysis and control unit with the ARM processor as the core; Among them, the FPGA processor is communicatively connected to the ARM processor; The laser energy acquisition unit and the quadrant signal acquisition unit are communicatively connected to the beam control component through an ADC; The X / Y scanner control unit and the Z scanner control unit are communicatively connected to the beam scanning component through an ADC; The confocal detector energy acquisition unit is communicatively connected to the reflection confocal detection component through an ADC; The laser energy analysis and control unit determines whether the energy meets the setting according to the laser energy value collected by the laser energy acquisition unit, and can adjust the laser power; The beam position analysis and control unit determines whether the beam position meets the setting according to the data collected by the quadrant signal acquisition unit, and can adjust the position of the beam in the X / Y plane; The confocal adjustment and confocal position analysis and control unit determines whether the reflection light focusing position is conjugate to the focus on the contact lens according to the laser energy value collected by the confocal detector energy acquisition unit. When the foci are conjugate, the position of the Z-axis scanner is obtained.

10. A method for quickly positioning the vertex of a contact lens for a femtosecond laser surgical device, characterized in that, It includes the following steps: a) Install the contact lens, turn on the solenoid valve to generate negative pressure, and ensure the proper installation of the contact lens according to the negative pressure value detected by the negative pressure sensor; b) The femtosecond laser emits a pulsed laser beam, which is transmitted to the beam control component. The beam control component detects the laser energy and position information, and transmits the information to the data analysis and processing component for beam position and output port energy adjustment; c) The beam is transmitted to the beam scanning component, and the objective lens focuses the beam. The X / X scanner controls the focus at the center of the contact lens; d) The reflected light is transmitted to the reflection confocal detection component. The lens group focuses the reflected beam, and the precision aperture adjusts the position to make the focused focus at the center of the aperture; e) Control the Z scanner to move from a position away from the output port towards the main optical path transmission direction, and at the same time, the confocal photodetector records the reflected light energy when the Z scanner moves one step; f) Collect the energy information, fit the "Z scanner position - reflected light energy" curve, and find the position of the Z scanner corresponding to the maximum energy after smoothing; g) Control the Z scanner to move to the position where the reflected energy is maximum. At this time, the beam is focused on the vertex of the contact lens.

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