Double wedge plate aberration compensator, laser processing observation system, methods and applications

Abstract

This invention provides a double wedge plate aberration compensator, a laser processing observation system, method, and application, belonging to the field of optical imaging technology. It includes a first wedge plate, configured as a fixed unit; a second wedge plate, whose wedge surface is placed face-to-face with the wedge surface of the first wedge plate; a first driving mechanism for driving the second wedge plate to move linearly along its own wedge-shaped inclined surface; a laser source; a microscope objective; an observation optical path; a second driving mechanism configured to carry and drive the crystal to be processed to move along the optical axis of the microscope objective; and a controller configured to coordinate and control the displacement of the second wedge plate and the crystal to be processed. By employing a double wedge plate translation mechanism, continuous, linear, and precisely adjustable equivalent compensation thickness is achieved, enabling real-time and dynamic compensation of precise optical path difference caused by changes in the depth of the crystal to be processed.

Description

Technical Field

[0001] This invention belongs to the field of optical imaging technology, specifically a double wedge plate aberration compensator, a laser processing observation system, a method, and its application. Background Technology

[0002] In fields such as laser processing, high-resolution photonic storage data reading, chip wafer processing and defect detection technology, achieving the integration of high-precision laser processing and high-resolution real-time observation is key to improving processing quality and process controllability.

[0003] However, when the laser beam focused by the objective lens penetrates a crystal of a certain thickness, the varying optical path difference between the object and working sides due to different crystal thicknesses leads to significant spherical aberration and focal drift, resulting in a severe degradation of focusing and detection imaging quality. In particular, this aberration worsens dramatically with increasing laser processing depth, causing a decrease in focused spot energy density, loss of processing size control, and a severe degradation of detection imaging quality, severely restricting the fabrication accuracy and consistency of deep structures.

[0004] Limited by the optical diffraction limit and ultra-small depth of field of traditional microscopes, existing technologies cannot meet the requirements of laser processing and high-resolution imaging over a large depth range. Therefore, there is an urgent need to develop a device and method that can integrate variable distance aberration compensation with laser processing and microscopic observation depth. This device and method aim to dynamically compensate for aberrations caused by changes in crystal depth and thickness, in order to support the precision manufacturing of next-generation high-performance large-depth integrated photonic devices and three-dimensional optical storage technologies, as well as the detection of defects in large-depth wafers. Summary of the Invention

[0005] To address the shortcomings of the prior art, the technical problem to be solved by the embodiments of the present invention is to provide a double wedge plate aberration compensator, a laser processing observation system, a method, and an application.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution:

[0007] A double-wedge plate aberration compensator, used for dynamic aberration compensation, comprising:

[0008] The first wedge-shaped plate is configured to be fixed.

[0009] The second wedge-shaped plate has its wedge-shaped surface facing the wedge-shaped surface of the first wedge-shaped plate, and the material of the second wedge-shaped plate is the same as that of the first wedge-shaped plate.

[0010] A first driving mechanism is connected to a second wedge-shaped plate and is used to drive the second wedge-shaped plate to move linearly along its own wedge-shaped inclined surface.

[0011] As a further improvement: the first drive mechanism includes a stepper motor, a ball screw driven by the stepper motor, and a slide table driven by the ball screw and carrying the second wedge-shaped plate.

[0012] As a further improvement: the first wedge plate and the second wedge plate have the same wedge angle, and the first driving mechanism further includes a stepper motor driver that is communicatively connected to the controller. The controller calculates the required number of pulses based on the target equivalent optical thickness change and the wedge angle and sends it to the stepper motor driver.

[0013] This invention also provides a laser processing observation system, which is an integrated system for laser processing and microscopic observation for dynamic aberration compensation, specifically comprising:

[0014] Laser source, used to generate laser light for processing;

[0015] A microscope objective is used to focus the processing laser into the interior of the crystal to be processed;

[0016] An observation optical path is used to perform real-time microscopic imaging of the processing area of ​​the crystal to be processed. The observation optical path includes at least a beam splitter and a detector.

[0017] A double wedge plate aberration compensator is disposed in the optical path between the laser source and the crystal to be processed;

[0018] The second drive mechanism is configured to carry and drive the crystal to be processed to move along the optical axis of the microscope objective.

[0019] The controller, which is communicatively connected to the first drive mechanism and the second drive mechanism, is configured to coordinate the control of the displacement of the second wedge plate relative to the crystal to be processed.

[0020] As a further improvement: a collimating beam expander group for adjusting the beam diameter and numerical aperture is provided between the laser source and the microscope objective.

[0021] As a further improvement, it also includes a beam splitter and a detector disposed in the optical path. The beam splitter is disposed in the optical path between the collimating beam expander group and the microscope objective. The beam splitter is used to split the beam from the microscope objective. The detector is used to receive one of the beams and form an observation image. The controller or the host computer connected to it performs focus verification or processing monitoring based on the observation image.

[0022] As a further improvement: the double wedge plate aberration compensator is disposed in the optical path between the laser source and the collimating beam expander group.

[0023] As a further improvement, the double wedge plate aberration compensator is disposed in the optical path between the beam splitter and the detector.

[0024] As a further improvement: the double wedge plate aberration compensator is disposed in the optical path between the beam splitter and the microscope objective.

[0025] The present invention also provides a compensation method for a laser processing observation system, the method comprising:

[0026] Determine the target processing depth;

[0027] Based on the target processing depth, calculate the first displacement of the crystal to be processed along the optical axis and the change in the equivalent optical thickness required to compensate for the resulting aberrations.

[0028] Based on the change in the equivalent optical thickness and the wedge angle, calculate the second displacement that the second wedge plate needs to move;

[0029] The crystal to be processed is moved by the first displacement amount by the second driving mechanism so as to position the processing focus to the target depth;

[0030] The second wedge plate is moved by the second displacement by the first driving mechanism, so as to change the equivalent optical thickness of the assembly formed by the second wedge plate and the first wedge plate placed face to face.

[0031] After aberration compensation is completed, laser processing and microscopic observation operations are performed.

[0032] As a further improvement, the following steps are included before performing laser processing and microscopic observation operations:

[0033] The detector acquires compensated observation images;

[0034] Analyze the observed image to automatically determine whether focusing has been completed and whether the processing point is located at the target position;

[0035] The laser processing operation is triggered only after verification is passed.

[0036] The present invention also provides an application of a double wedge plate aberration compensator in an optical microscope for dynamic aberration compensation when performing deep imaging of transparent or semi-transparent multilayer samples.

[0037] This invention also provides an application of a laser processing observation system in biomedical imaging, which is used to perform high-resolution deep imaging of multilayer fluorescently labeled biological samples. By compensating for depth-induced aberrations to match the refractive index of different depth layers, clear imaging across the entire depth is ensured.

[0038] This invention also provides an application of a laser processing observation system in semiconductor inspection, which is used to detect defects in chips with multiple dielectric layers or complex three-dimensional structures. By compensating for aberrations caused by changes in layer thickness in real time, it enables non-destructive, high-definition observation of the internal structure of the chip.

[0039] This invention also provides an application of a laser processing observation system in the manufacture of photonic devices, which is used to perform three-dimensional selective laser modification inside crystal or glass materials to fabricate waveguides, gratings or photonic integrated circuit structures.

[0040] This invention also provides an application of a laser processing observation system in data storage, which is used to perform multi-layer or multi-point laser writing and reading in a transparent storage medium to realize three-dimensional optical data storage.

[0041] Compared with the prior art, the beneficial effects of the present invention are: by adopting the double wedge plate translation mechanism, the equivalent compensation thickness is continuously, linearly, and precisely adjustable, and can compensate for the precise optical path difference caused by the change in the depth of the crystal to be processed in real time and dynamically;

[0042] By sharing the microscope objective and the beam splitter, the laser processing optical path and the microscopic aiming optical path are coaxial and integrated in real time. While dynamically compensating for aberrations, the system can use the detector to acquire images in real time and automatically perform focus judgment and position verification through the host computer software, forming an intelligent closed loop of "perception-computation-compensation-processing-re-perception". Attached Figure Description

[0043] Figure 1 This is a diagram of an optical model for aberration compensation using an equivalent flat plate.

[0044] Figure 2 The diagrams show the optical path at different processing depths, where (a) represents the first depth, (b) represents the second depth, and (c) represents the third depth.

[0045] Figure 3 for Figure 2 (a) MTF curve corresponding to the first depth;

[0046] Figure 4 for Figure 2 (b) MTF curve corresponding to the second depth;

[0047] Figure 5 for Figure 2 (c) MTF curve corresponding to the third depth;

[0048] Figure 6 The diagram shows a theoretical model for aberration compensation using a double wedge plate in different shapes.

[0049] Figure 7 for MTF curve at 1µm;

[0050] Figure 8 for It is 1µm. MTF curve at 1µm;

[0051] Figure 9 This is a schematic diagram of the device;

[0052] Figure 10 This is a structural diagram of the device;

[0053] Figure 11 Workflow diagram;

[0054] In the figure, 10 is the first wedge-shaped plate; 20 is the second wedge-shaped plate. Detailed Implementation

[0055] The technical solution of this application will be further described in detail below with reference to specific embodiments.

[0056] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0057] Please see Figure 1 , Figure 2 and Figure 6 In one embodiment, a double-wedge aberration compensator, the double-wedge aberration compensator being used for dynamic aberration compensation, includes:

[0058] The first wedge-shaped plate 10 is configured to be fixed.

[0059] The second wedge-shaped plate 20 has its wedge-shaped surface placed face-to-face with the wedge-shaped surface of the first wedge-shaped plate 10, and the material of the second wedge-shaped plate 20 is the same as that of the first wedge-shaped plate 10.

[0060] A first driving mechanism is connected to a second wedge-shaped plate 20 and is used to drive the second wedge-shaped plate 20 to move linearly along its own wedge-shaped inclined surface.

[0061] In this embodiment, the first wedge plate 10 and the second wedge plate 20 constitute a double wedge plate, using two wedge plates placed opposite each other to represent the continuous change in the thickness of the parallel plate. The first wedge plate 10 is fixed, while the second wedge plate 20 moves linearly along its hypotenuse, causing a linear change in the center thickness of the assembly.

[0062] In one embodiment, the first drive mechanism includes a stepper motor, a ball screw driven by the stepper motor, and a slide table driven by the ball screw and carrying the second wedge-shaped plate 20.

[0063] In this embodiment, the first drive mechanism consists of a stepper motor, a ball screw, a guide rail, a slide table, a slider, a coupling, and other supporting structures. A hybrid stepper motor is selected, which has high holding torque and good low-speed performance. The stepper motor driver should have microstepping functionality; microstepping significantly improves motion smoothness and resolution, and reduces vibration and noise. The stepper motor rotates the shaft, and the motor is connected to the ball screw via a coupling. The bearing is locked by the bearing housing's clamping edge, preventing axial movement of the ball screw assembly. The ball screw assembly is engaged via a threaded connection, thereby allowing the slider to move linearly.

[0064] In one embodiment, the first wedge plate 10 and the second wedge plate 20 have the same wedge angle. The first drive mechanism further includes a first stepper motor driver that is communicatively connected to a controller. The controller calculates the required number of pulses based on the target equivalent optical thickness change and the wedge angle and sends the calculations to the first stepper motor driver.

[0065] This invention also provides a laser processing observation system, which is an integrated system for laser processing and microscopic observation for dynamic aberration compensation, specifically comprising:

[0066] Laser source, used to generate laser light for processing;

[0067] A microscope objective is used to focus the processing laser into the interior of the crystal to be processed;

[0068] An observation optical path is used to perform real-time microscopic imaging of the processing area of ​​the crystal to be processed. The observation optical path includes at least a beam splitter and a detector.

[0069] The aforementioned double wedge plate aberration compensator is disposed in the optical path between the crystal to be processed and the microscope objective;

[0070] The second drive mechanism is configured to carry and drive the crystal to be processed to move along the optical axis of the microscope objective.

[0071] The controller, which is communicatively connected to the first drive mechanism and the second drive mechanism, is configured to coordinate the control of the displacement of the second wedge plate 20 relative to the crystal to be processed.

[0072] A collimating and expanding lens group for adjusting the beam diameter and numerical aperture is provided between the laser source and the microscope objective.

[0073] It also includes a beam splitter and a detector disposed in the optical path. The beam splitter is used to split the light beam from the microscope objective, and the detector is used to receive one of the beams and form an observation image. The controller or the host computer connected to it performs focus verification or processing monitoring based on the observation image.

[0074] In this embodiment, when using a microscope objective to perform laser processing or readout detection on the crystal, the crystal can be considered as a parallel plate, with the focal point of the microscope objective located at the rightmost side of the crystal to be processed. When the crystal moves to the right, an equivalent plate made of the same material as the crystal to be processed is used to compensate for the optical path difference; its thickness is the same as the moving distance of the crystal. Simultaneously, a distance is left at each end of the equivalent plate to facilitate subsequent assembly, such as... Figure 1 As shown.

[0075] This invention is also an integrated system combining optics, mechanics, and electronics, with each hardware unit working collaboratively to achieve dynamic aberration compensation integrating laser processing and microscopic observation. The specific device consists of a laser, a collimating and beam-expanding lens group, a beam splitter, a detector, a microscope objective, a double wedge plate, two linear displacement stages, two stepper motor drives, a controller, a host computer, and the crystal to be processed. Figure 9 This is a schematic diagram of the device. Figure 10 This is a structural diagram of the device.

[0076] The laser generates a laser beam of fixed wavelength, responsible for laser processing of the crystal to be processed; the collimating and beam-expanding lens group at the right end of the laser achieves the matching of the laser's exit angle and numerical aperture; the beam splitter divides the incident beam into two paths, the transmitted light path serving as the laser processing light path, and the reflected light path serving as the microscopic aiming light path; the microscope objective is installed after the collimating and beam-expanding lens group, responsible for focusing the laser beam onto the target point inside the crystal; the detector receives the optical signal from the microscopic aiming light path and converts it into an electrical signal, forming a real-time image that is transmitted to the host computer for focusing and processing monitoring, while simultaneously completing the closed-loop control of the entire system.

[0077] The double wedge plate and the crystal to be processed are made of fused silica glass. The first wedge plate 10 is fixed on the optical platform and is located in the optical path behind the double wedge plate. The second wedge plate 20 is a movable part and is installed on the slider of the first electric linear displacement stage. It can continuously and linearly change the equivalent thickness of the assembly by moving in the y direction, thereby dynamically compensating for aberrations such as spherical aberration due to changes in processing depth, and ensuring that a diffraction-limited focused spot can be obtained at any depth. The crystal to be processed is fixed on the slider of the second electric linear displacement stage.

[0078] Both the first and second drive mechanisms consist of a stepper motor, ball screw, guide rail, slide table, slider, coupling, and other supporting structures. Based on the different displacement distances of the second wedge-shaped plate 20 and the crystal under test, the first drive mechanism uses a 30mm ball screw, and the second drive mechanism uses a 15mm ball screw; all other component parameters are identical. The first drive mechanism drives the second wedge-shaped plate 20 in linear motion; this displacement table is the core mechanism for aberration compensation. The second drive mechanism carries the crystal under test in linear motion along the optical axis; this displacement table ensures the processing focus is located inside the crystal.

[0079] The controller is the real-time control core of the system. It executes instructions issued by the host computer and is responsible for specific logic operations and motion control tasks. It is connected to the host computer via a communication cable. The stepper motor driver is responsible for receiving pulse signals and direction signals from the controller, amplifying them into high-voltage electrical signals that can drive the stepper motors. Each driver is connected to a stepper motor of a linear displacement stage.

[0080] The double wedge plate can also be integrated into the system in three different optical path positions to complete aberration compensation respectively.

[0081] When the double wedge plate is integrated between the laser and the collimating beam expander group, before the laser processing begins, the double wedge plate is driven in advance to adjust the equivalent thickness according to the preset processing depth information, so as to complete the aberration compensation before the beam enters the collimating beam expander group.

[0082] When the double wedge plate is integrated between the beam splitter and the detector, the detector acquires images, and the host computer controls the double wedge plate to adjust the equivalent thickness based on the degree of image blur, thereby completing the aberration compensation of the microscopic aiming optical path.

[0083] When the double wedge plate is integrated between the beam splitter and the microscope objective, the equivalent thickness is adjusted by driving the double wedge plate, and the aberrations of the laser processing optical path and the microscope aiming optical path are compensated synchronously.

[0084] For residual aberrations that may exist after compensation with double wedge plates, the system can be further integrated with a spatial light modulator to effectively correct higher-order aberrations and asymmetric aberrations.

[0085] The present invention also provides a compensation method for a laser processing observation system, the method comprising:

[0086] Determine the target processing depth;

[0087] Based on the target processing depth, calculate the first displacement of the crystal to be processed along the optical axis and the change in the equivalent optical thickness required to compensate for the resulting aberrations.

[0088] Based on the change in the equivalent optical thickness and the wedge angle, calculate the second displacement that the second wedge plate 20 needs to move;

[0089] The crystal to be processed is moved by the first displacement amount by the second driving mechanism so as to position the processing focus to the target depth;

[0090] The second wedge plate 20 is moved by the second displacement by the first driving mechanism, so as to change the equivalent optical thickness of the assembly formed by the second wedge plate 20 and the first wedge plate 10 placed face to face.

[0091] After aberration compensation is completed, laser processing and microscopic observation operations are performed.

[0092] In this embodiment, the relationship between the thickness d of the equivalent plate formed by the first wedge plate 10 and the second wedge plate 20 and the moving distance l along the hypotenuse direction is as follows: ;

[0093] Where θ is the wedge angle of the wedge plate. Due to system size limitations, the equivalent thickness of the double-wedge plate assembly has a minimum value and cannot cover the case of zero thickness. Therefore, the equivalent thickness of this assembly has a minimum value, that is, the equivalent thickness starts to change from d1;

[0094] ;

[0095] Where h is the height of the crystal to be processed.

[0096] Therefore, the machinable depth d2 is: ;

[0097] Where L is the working distance of the microscope objective, L 装配 This is the distance from the last plane of the microscope in the initial structure to the leftmost end of the crystal to be processed. Figure 6 As a theoretical model for aberration compensation using a double wedge plate, when the crystal to be processed moves to the right, the second wedge plate 20 moves, and at the same time the thickness of the assembly gradually increases, thus completing aberration correction.

[0098] The errors in this invention mainly consider the pulse equivalent error of motion control and the pitch error of the lead screw during transmission, and the above errors are allocated as follows:

[0099] Pulse equivalent error is the minimum displacement that the system can execute, that is, the theoretical displacement that the stage can move for each pulse signal issued by the controller, also known as the system resolution. It is a quantization error. When the target displacement is not an integer multiple of the pulse equivalent, the system can only move to the position closest to the pulse equivalent multiple, thus producing a positioning error of no more than 1 pulse equivalent.

[0100] ;

[0101] Where S is the lead of the ball screw, α is the step angle of the stepper motor, and p is the microstepping of the stepper motor driver.

[0102] Based on the hardware selection, the distribution of pulse equivalent error is as follows:

[0103] .

[0104] Pitch error When using a linear displacement stage to control the movement of optical elements, the positioning accuracy is limited by the pitch error of the ball screw.

[0105] , ;

[0106] in, This represents the actual displacement of the nut. This represents the ideal displacement of the nut. The pitch of the ball screw. For the angular displacement of the ball screw, This refers to the number of revolutions of the ball screw.

[0107] Then pitch error The displacement deviation of the linear displacement stage is:

[0108]

[0109] Based on the precision grade of the lead screw, the displacement deviation caused by the pitch error is distributed as follows:

[0110]

[0111] The first drive mechanism uses a first electric linear displacement stage, which controls the movement of the second wedge-shaped plate 20. The second drive mechanism uses a second electric linear displacement stage, which controls the movement of the crystal to be processed. Therefore, the lateral displacement error of the double wedge plate is equivalent to that of the flat plate. for:

[0112] ;

[0113] in, The pulse equivalent error of the first electric linear displacement stage. This represents the displacement deviation of the first electrically driven linear displacement stage. The displacement error of the crystal under test. for:

[0114] ;

[0115] in, The pulse equivalent error of the second electric linear displacement stage. This represents the displacement deviation of the second electric linear displacement stage.

[0116] According to the formula for spherical difference in parallel plates:

[0117] ;

[0118] Where n is the refractive index of the wedge-shaped plate, d0 is the equivalent thickness of the parallel plate, and u is the incident angle onto the parallel plate, according to the definition of the numerical aperture of a microscope and the law of refraction:

[0119] , ;

[0120] in, Given the exit angle of the object exiting from the parallel plate, the incident angle u can be obtained as follows:

[0121] ;

[0122] This allows us to obtain the lateral displacement error of the equivalent flat plate using the double wedge block. Caused ball difference for:

[0123] ;

[0124] Similarly, the displacement deviation of the crystal to be processed along the optical axis The effect of spherical aberration on the crystal under test is as follows:

[0125] ;

[0126] Therefore, the total spherical difference for:

[0127] ;

[0128] Based on the above formulas, the microscope numerical aperture, crystal refractive index, and lateral displacement error of the equivalent plate of the double wedge block can be obtained. and the displacement deviation of the crystal along the optical axis The impact of spherical aberration on the image surface. Simulation analysis was performed using Zemax software. Figure 7 Showing The MTF curve is for 1µm. Figure 8 Showing It is 1µm. The MTF curve for 1µm shows that... and The effect on aberrations is the opposite.

[0129] Simulation analysis was performed using Zemax software. Figures 2-5 The optical path diagrams and corresponding MTF curves are shown when the crystal to be processed moves to the right at different processing depths. The MTF curves are all close to the diffraction limit.

[0130] In one embodiment, the procedure further includes the following steps prior to performing the laser processing operation and the microscopic observation operation:

[0131] The detector acquires compensated observation images;

[0132] Analyze the observed image to automatically determine whether focusing has been completed and whether the processing point is located at the target position;

[0133] The laser processing operation is triggered only after verification is passed.

[0134] In this embodiment, the workflow diagram of the present invention is as follows: Figure 11 As shown, the specific process is as follows:

[0135] First, turn on the main system power. The host computer, controller, and stepper motor driver will then be powered on sequentially. The host computer starts the control software and establishes a connection with the controller through the communication interface.

[0136] The host computer sends a "return to zero" message to the controller, executing the internal zero-return procedure. The controller first sends a pulse to the first stepper motor driver, driving the upper wedge plate to move in the negative direction until the block on the linear displacement stage triggers the limit sensor. The sensor signal is input to the controller. When the controller detects this signal, it immediately stops sending pulses and resets its internal position counter to zero. Similarly, the controller sends a pulse to the second stepper motor driver, driving the crystal to be processed to move, triggering the limit sensor, stopping, and resetting the position counter to zero.

[0137] Set the target machining depth d0 in the host computer software interface. The displacement x of the upper wedge plate and the displacement y of the crystal to be processed are calculated.

[0138] , ;

[0139] The host computer then calculates the number of pulses N1 and N2 based on the parameters of the lead screw and stepper motor, and sends them to the controller through the communication interface.

[0140] , ;

[0141] The controller sends pulse quantity N1 to the first stepper motor driver and pulse quantity N2 to the second stepper motor driver through two independent high-speed pulse output channels.

[0142] The controller monitors the number of pulses sent in real time through an internal counter. When the number of pulses reaches the target values ​​N1 and N2, the controller's internal "positioning complete" flag is set, and the controller sends "positioning complete" information to the host computer.

[0143] After receiving the "positioning complete" message, the host computer instructs the detector to acquire the current image and send it to the host computer. The host computer analyzes the image and automatically determines whether the focus is complete and whether the processing point is located at the target position. After the image is confirmed to be aimed, a "start processing command" is sent to the controller. After receiving the command, the controller provides a high-level signal with a duration of T to the laser through its digital output module, triggering the laser output.

[0144] The host computer updates the next depth value and repeats the process. Once all processing is complete, the host computer sends a "return to zero" message, and the process ends.

[0145] The present invention also provides an application of a double wedge plate aberration compensator in an optical microscope for dynamic aberration compensation when performing deep imaging of transparent or semi-transparent multilayer samples.

[0146] This invention also provides an application of a laser processing observation system in biomedical imaging, which is used to perform high-resolution deep imaging of multilayer fluorescently labeled biological samples. By compensating for depth-induced aberrations to match the refractive index of different depth layers, clear imaging across the entire depth is ensured.

[0147] This invention also provides an application of a laser processing observation system in semiconductor inspection, which is used to detect defects in chips with multiple dielectric layers or complex three-dimensional structures. By compensating for aberrations caused by changes in layer thickness in real time, it enables non-destructive, high-definition observation of the internal structure of the chip.

[0148] This invention also provides an application of a laser processing observation system in the manufacture of photonic devices, which is used to perform three-dimensional selective laser modification inside crystal or glass materials to fabricate waveguides, gratings or photonic integrated circuit structures.

[0149] This invention also provides an application of a laser processing observation system in data storage, which is used to perform multi-layer or multi-point laser writing and reading in a transparent storage medium to realize three-dimensional optical data storage.

[0150] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention, and no reference numerals in the claims should be construed as limiting the scope of the claims.

[0151] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider 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 laser machining observation system, characterized by, The laser processing observation system is a laser processing and microscopic observation integrated system for dynamic aberration compensation, and specifically comprises: a laser source for generating processing laser; a microscopic objective for focusing the processing laser inside a crystal to be processed; an observation light path for real-time microscopic imaging of a processing region of the crystal to be processed, the observation light path comprising at least a beam splitter and a detector; a double-wedge plate aberration compensator arranged in the light path between the laser source and the crystal to be processed; the double-wedge plate aberration compensator is used for dynamic aberration compensation, and comprises: a first wedge plate configured to be fixedly arranged; a second wedge plate having a wedge surface placed against a wedge surface of the first wedge plate, and the second wedge plate is made of the same material as the first wedge plate; a first driving mechanism connected with the second wedge plate and used for driving the second wedge plate to move linearly along the wedge surface of the second wedge plate; a second driving mechanism configured to carry and drive the crystal to be processed to move along the optical axis of the microscopic objective; a controller in communication connection with the first driving mechanism and the second driving mechanism and configured to coordinately control the displacement of the second wedge plate and the crystal to be processed.

2. A laser machining observation system according to claim 1, wherein The first driving mechanism comprises a stepper motor, a ball screw driven by the stepper motor, and a sliding table driven by the ball screw and carrying the second wedge plate.

3. A laser machining observation system according to claim 2, wherein The first wedge plate and the second wedge plate have the same wedge angle, and the first driving mechanism further comprises a stepper motor driver in communication connection with the controller, and the controller calculates the required pulse number according to the target equivalent optical thickness variation and the wedge angle and sends the pulse number to the stepper motor driver.

4. The laser machining observation system of claim 1, wherein A collimating and expanding mirror group is arranged between the laser source and the microscopic objective for adjusting the beam diameter and numerical aperture.

5. A laser machining observation system according to claim 4, wherein The system further comprises a beam splitter and a detector arranged in the light path, the beam splitter is arranged in the light path between the collimating and expanding mirror group and the microscopic objective, the beam splitter is used for splitting the light beams from the microscopic objective, the detector is used for receiving one of the light beams and forming an observation image, and the controller or an upper computer connected therewith performs focusing verification or processing monitoring according to the observation image.

6. The laser machining observation system of claim 4, wherein, The double-wedge plate aberration compensator is arranged in the light path between the laser source and the collimating and expanding mirror group.

7. The laser machining observation system of claim 4, wherein, The double-wedge plate aberration compensator is arranged in the light path between the beam splitter and the detector.

8. The laser machining observation system of claim 4, wherein, The double-wedge plate aberration compensator is arranged in the light path between the beam splitter and the microscopic objective.

9. The laser machining observation system of claim 4, wherein, The double-wedge plate aberration compensator is arranged in the light path between the microscopic objective and the crystal to be processed.

10. The method of claim 1-9, wherein, The method comprises: determining a target processing depth; calculating a first displacement of the crystal to be processed along the optical axis and a variation of the equivalent optical thickness required for compensating the aberration caused thereby according to the target processing depth; calculating a second displacement of the second wedge plate to be moved according to the variation of the equivalent optical thickness and the wedge angle; driving the second wedge plate to move the second displacement amount by the first driving mechanism to change the equivalent optical thickness of the combination of the second wedge plate and the first wedge plate; driving the second wedge plate to move the second displacement amount by the first driving mechanism to change the equivalent optical thickness of the combination of the second wedge plate and the first wedge plate; performing laser processing operation and microscopic observation operation after the completion of aberration compensation.

11. The compensation method according to claim 10, characterized in that, Before performing laser processing operation and microscopic observation operation, further comprising: acquiring the compensated observation image by the detector; analyzing the observation image to automatically determine whether the focusing is completed and the processing point is located at the target position; only after the verification is passed, triggering the laser processing operation.

12. Use of a laser machining observation system according to any one of claims 1 to 9 in an optical microscope, characterized in that, Aberration dynamic compensation for deep layer imaging of transparent or semi-transparent multi-layer samples.

13. Use of a laser machining observation system according to any one of claims 1 to 9 in biomedical imaging, characterized in that, Applied to high-resolution deep layer imaging of multi-layer fluorescent-labeled biological samples, compensating for depth-induced aberrations to match the refractive index of different depth layers to ensure clear full-depth imaging.

14. Use of a laser processing observation system according to any one of claims 1 to 9 in semiconductor inspection, characterized in that, Applied to defect detection of chips with multi-layer dielectric layers or complex three-dimensional structures, real-time compensation for aberrations caused by changes in layer thickness to achieve non-destructive and high-definition observation of internal chip structures.

15. Use of a laser processing observation system according to any one of claims 1 to 9 in the manufacture of photonic devices, characterized in that, Applied to three-dimensional selective laser modification inside crystal or glass materials to make waveguide, grating or photonic integrated circuit structures.

16. Use of a laser machining observation system according to any one of claims 1 to 9 in data storage, characterized in that, Applied to multi-layer or multi-point laser inscription and reading in transparent storage media to achieve three-dimensional optical data storage.

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