A lightweight femtosecond pulse waveguide forming process

Abstract

This invention discloses a lightweight femtosecond pulsed waveguide forming process. Utilizing the ultrashort pulse characteristics of femtosecond lasers, a local refractive index change is generated within a transparent dielectric material, thereby forming a high-quality waveguide structure. This process achieves flexible design and efficient fabrication of the waveguide path by precisely controlling the pulse energy, repetition frequency, and scanning speed of the femtosecond laser. Femtosecond lasers can scan freely in three-dimensional space, enabling flexible design and fabrication of complex waveguide structures, expanding the application range of waveguides. Precise control of laser parameters can effectively reduce micro-defects on the waveguide surface, improving transmission loss and geometric accuracy. Femtosecond laser processing is fast and simple, suitable for large-scale production and rapid iteration, reducing manufacturing costs. This invention provides an efficient, flexible, and high-precision waveguide forming process, solving problems existing in the prior art and significantly improving the fabrication quality and application potential of waveguides.

Description

Technical Field

[0001] This invention belongs to the field of waveguide forming technology, specifically relating to a lightweight femtosecond pulse waveguide forming process. Background Technology

[0002] In the current fields of optical communication and optical interconnection, waveguide fabrication is one of the key technologies for achieving efficient optical transmission. Traditional waveguide fabrication methods mainly include ion exchange, sol-gel method, ultraviolet exposure, and electron beam etching. While these methods can meet the requirements of waveguide fabrication to some extent, they have significant limitations in terms of flexibility, accuracy, and efficiency.

[0003] Ion exchange method: This method involves immersing a glass material in a molten salt, allowing ions to diffuse across the material's surface and thus altering the local refractive index. While simple to operate, this method struggles to achieve complex three-dimensional waveguide structures, and the limited refractive index change affects the waveguide's transmission performance.

[0004] Sol-gel method: A thin film with different refractive indices is formed on a substrate through a chemical reaction, and then a waveguide is formed through photolithography and etching processes. This method can fabricate relatively complex waveguide structures, but the process is complex, time-consuming, and costly.

[0005] Ultraviolet (UV) exposure: This method utilizes ultraviolet light to induce a change in the refractive index of a photosensitive material, forming a waveguide. This method is suitable for specific types of photosensitive materials, but its selectivity is high, and the range of refractive index changes is limited, thus restricting its application.

[0006] Electron beam etching: Waveguide structures are etched onto the surface of a material using an electron beam. This method can achieve high-precision waveguide fabrication, but the equipment is expensive, the operation is complex, and it is not suitable for large-scale production.

[0007] While the methods described above each have their advantages in waveguide fabrication, they also share some common technical challenges, especially in fabricating high-quality, high-precision three-dimensional waveguide structures. These challenges mainly include:

[0008] Insufficient flexibility: Traditional methods make it difficult to achieve flexible design and fabrication of complex three-dimensional waveguide structures, which limits the application range of waveguides.

[0009] Low precision: Traditional methods are prone to introducing tiny defects during the fabrication process, which increases the transmission loss of the waveguide and affects its optical performance.

[0010] Inefficient: Traditional methods are complex, time-consuming, and costly, which is not conducive to large-scale production and rapid iteration. Summary of the Invention

[0011] The purpose of this invention is to provide a lightweight femtosecond pulse waveguide forming process, which achieves flexible design and efficient processing of waveguide paths by precisely controlling the pulse energy, repetition frequency and scanning speed of the femtosecond laser, thereby solving the problems mentioned in the background art.

[0012] The purpose of this invention is to provide a lightweight femtosecond pulse waveguide forming process, which achieves flexible design and efficient processing of waveguide paths by precisely controlling the pulse energy, repetition frequency and scanning speed of the femtosecond laser, thereby solving the problems mentioned in the background art.

[0013] To achieve the above objectives, the present invention adopts the following technical solution: a lightweight femtosecond pulse waveguide forming process, comprising the following steps:

[0014] S1: Provide a transparent medium material, which has good light transmittance and can withstand the action of femtosecond laser;

[0015] S2: Determine the path of the waveguide forming region on the material provided in step S1, and calculate the position sequence of the laser focusing point based on the required waveguide shape and size;

[0016] S3: Based on the position sequence determined in step S2, adjust the operating parameters of the femtosecond laser and set the pulse energy to ensure that a local refractive index change is generated inside the material without damaging the material structure;

[0017] S4: Using the parameters set in step S3, start the femtosecond laser and make the laser scan point by point inside the material along the path of the waveguide forming area planned in step S2 to form the initial waveguide profile.

[0018] S5: Perform quality inspection on the initial waveguide profile formed in step S4 to evaluate the waveguide's transmission loss and geometric accuracy;

[0019] S6: If the quality inspection result of step S5 does not meet the preset standard, then adjust the working parameters of the femtosecond laser in step S3 according to the inspection result, and optimize the pulse energy or repetition frequency of the femtosecond laser.

[0020] S7: Re-execute step S4 according to the parameters adjusted in step S6 until the waveguide's transmission loss and geometric accuracy meet the requirements.

[0021] S8: After waveguide forming is completed, the material is surface treated to remove minor defects that may be caused by laser action and improve the overall performance of the waveguide.

[0022] S9: Perform a final inspection on the waveguide processed in step S8 to confirm that all indicators of the waveguide meet the design requirements and complete the waveguide forming process.

[0023] Preferably, step S1 includes the following sub-processes:

[0024] S11: Select the type of transparent medium material to ensure that the refractive index n of the material meets the requirements, wherein the refractive index n should be greater than 1.4 and less than 1.6;

[0025] S12: Measurement step S11: Select the initial absorption coefficient α of the material. o And calculate the absorption enhancement factor F = exp(α) of the material under femtosecond laser irradiation. o L), where L is the laser penetration depth;

[0026] S13: Based on the absorption enhancement factor F in step S12, adjust the output power P of the laser to minimize the thermal effect generated inside the material. The calculation formula is P. adj =P initial / F, where P initial This represents the initial output power of the laser.

[0027] S14: Using the laser output power P adjusted in step S13 adj The selected transparent medium material is pretreated.

[0028] Preferably, step S2 includes the following sub-processes:

[0029] S21: Determine the boundary conditions of the waveguide shaping region and define the starting point P of the waveguide. s and termination point P e And the centerline path C of the waveguide;

[0030] S22: Based on the path C defined in step S21, calculate the waveguide width W and height H, and determine the shape of the waveguide cross-section;

[0031] S23: Using the waveguide cross-section shape determined in step S22, and combined with the waveguide centerline path C, calculate the position sequence S = {S1, S2, ..., S...} of the laser focusing point. n}, where S i For each location point, they are uniformly distributed along path C with a spacing of d. The calculation formula is: Where N is the total number of focal points;

[0032] S24: Optimize the position sequence S obtained in step S23, check whether the distance between adjacent focal points is uniform, and if non-uniformity is found, adjust the number of focal points N or recalculate the spacing d.

[0033] Preferably, step S3 includes the following sub-processes:

[0034] S31: Based on the position sequence of the laser focal points determined in step S2, calculate the total number of pulses M required for waveguide shaping, where M is equal to the number of focal points in the position sequence;

[0035] S32: Based on the total number of pulses M calculated in step S31, estimate the energy range of a single pulse to ensure that the total energy does not exceed the material's damage threshold. The calculation formula is as follows: Where E th The damage threshold energy of the material;

[0036] S33: Considering the energy accumulation effect during waveguide shaping, adjust the energy E of a single pulse so that the energy E of a single pulse is within the range of E... min and E max Between, the calculation formula is Where E min To ensure the minimum energy required for a change in refractive index;

[0037] S34: Apply the single pulse energy E determined in step S33 to the femtosecond laser, set the pulse energy parameters of the laser, and conduct preliminary tests to verify whether the pulse energy can effectively produce local refractive index changes without damaging the material.

[0038] Preferably, step S4 includes the following sub-processes:

[0039] S41: Initialize the operating parameters of the femtosecond laser according to the pulse energy E and total number of pulses M set in step S3;

[0040] S42: Based on the position sequence of the laser focal points determined in step S2, set the scanning path of the laser, so that the laser scans point by point along the path, scanning one focal point at a time, and calculate the total length L of the scanning path. total ,in S i S represents the position of the i-th focal point. i+1 Let i be the position of the (i+1)th focal point;

[0041] S43: Determine the laser scanning speed v to ensure that the laser interaction time at each focal point is sufficient to produce the required refractive index change. The calculation formula is as follows: Where t total Total scan time;

[0042] S44: Start the femtosecond laser and scan point by point according to the scanning speed v set in step S43 and the path set in step S42 to form the initial waveguide profile, and monitor the laser power and position deviation in real time during the scanning process.

[0043] Preferably, step S5 includes the following sub-processes:

[0044] S51: Use a high-precision optical microscope to check the geometric accuracy of the initial waveguide formed in step S4, record the deviations Δx in the x-direction and Δy in the y-direction between the actual path and the designed path of the waveguide, and calculate the geometric accuracy error.

[0045] S52: Based on the geometric accuracy error ε detected in step S51 geom To assess whether the waveguide's geometric accuracy meets the design requirements, if the error exceeds a preset threshold ε... max If so, the laser scanning parameters need to be adjusted and the waveguide reshaped.

[0046] S53: Measure the waveguide transmission loss using a spectrum analyzer, by inputting optical power P. in and output optical power P out Calculate transmission loss

[0047] S54: The transmission loss L measured in step S53 trans With respect to the required transmission loss threshold L max If the transmission loss exceeds the transmission loss threshold L, then... max If so, it is necessary to optimize the laser's pulse energy or scanning speed and reshape the waveguide.

[0048] Preferably, step S6 includes the following sub-processes:

[0049] S61: Based on the geometric accuracy error ε detected in step S5 geom and transmission loss L trans To determine whether the waveguide quality meets the preset standard, if the geometric accuracy error exceeds the threshold ε max Or the transmission loss exceeds the threshold L max Then proceed to the next step;

[0050] S62: Analyze the problems in the detection results of step S5, determine the parameters that need to be optimized, and if the main problem is that the geometric accuracy error is too large, then adjust the laser scanning speed v and calculate the new scanning speed.

[0051] S63: If the main problem is excessive transmission loss, adjust the laser pulse energy E and calculate the new pulse energy.

[0052] S64: Apply the adjusted parameters from step S62 or step S63 to the femtosecond laser, and repeat steps S4 to S5 until the waveguide quality test results meet the preset standards.

[0053] Preferably, step S7 includes the following sub-processes:

[0054] S71: Reinitialize the pulse energy E of the femtosecond laser according to the laser operating parameters adjusted in step S6. new and scanning speed v new ;

[0055] S72: Using the parameters set in step S71, re-execute the laser scanning process in step S4, so that the laser scans point by point inside the material along the path planned in step S2 to form a new waveguide profile.

[0056] S73: After completing the scan in step S72, perform the quality check in step S5 again to evaluate the transmission loss L of the new waveguide. trans and geometric accuracy error ε geom ;

[0057] S74: Compare the transmission loss L measured in step S73. trans and geometric accuracy error ε geom Compared with the preset standard value L max and ε max If the requirements are still not met, return to step S6 to continue adjusting the parameters until the waveguide quality meets the requirements.

[0058] Preferably, step S8 includes the following sub-processes:

[0059] S81: Use a high-resolution optical microscope to conduct a detailed inspection of the material surface after waveguide forming, identify and mark the tiny defect areas caused by laser action, denoted as the defect point set D;

[0060] S82: Based on the set of defect points D identified in step S81, calculate the area A of each defect point. i and depth d i And record these parameters;

[0061] S83: Based on the defect point parameters recorded in step S82, calculate the processing parameters. For chemical polishing, calculate the polishing solution concentration C and the processing time t, using the formula C = k1·max(A i ) and t = k2·max(d i ), where k1 and k2 are empirical constants;

[0062] S84: Apply the processing parameters determined in step S83 to process the material surface, remove defects, and then re-examine the surface using an optical microscope.

[0063] Preferably, step S9 includes the following sub-processes:

[0064] S91: Perform a final inspection of the waveguide surface processed in step S8 using an optical microscope, and record the surface roughness parameter R. The calculation formula is as follows: Where h j The height h of each measurement point avg N is the average height of all measurement points. s The number of measurement points;

[0065] S92: Based on the roughness parameter R measured in step S91, evaluate whether the roughness of the waveguide surface meets the design requirements. If the roughness parameter exceeds the preset threshold R... thresh If so, the surface treatment in step S8 needs to be repeated;

[0066] S93: Measure the final transmission loss of the waveguide using a spectral analyzer, by inputting optical power P. input and output optical power P output Calculate the final transmission loss And compare it with the data in step S5 to ensure that the transmission loss has not worsened due to the surface treatment;

[0067] S94: Based on the test results from steps S91 to S93, confirm that all indicators of the waveguide meet the design requirements and complete the waveguide forming process.

[0068] Technical effects and advantages of the present invention: The lightweight femtosecond pulse waveguide forming process proposed in this invention has the following advantages compared with the prior art:

[0069] This invention utilizes the ultrashort pulse characteristics of femtosecond lasers to induce localized refractive index changes within transparent dielectric materials, thereby forming high-quality waveguide structures. This process achieves flexible design and efficient fabrication of waveguide paths through precise control of the femtosecond laser's pulse energy, repetition frequency, and scanning speed. Femtosecond lasers can freely scan in three-dimensional space, enabling flexible design and fabrication of complex waveguide structures, expanding the application range of waveguides. Precise control of laser parameters effectively reduces minute defects on the waveguide surface, improving transmission loss and geometric accuracy. Femtosecond laser processing is fast, simple, suitable for large-scale production and rapid iteration, and reduces manufacturing costs. This invention provides an efficient, flexible, and high-precision waveguide forming process, solving problems existing in current technologies and significantly improving the fabrication quality and application potential of waveguides. Attached Figure Description

[0070] Figure 1 This is a flowchart of a lightweight femtosecond pulse waveguide forming process according to the present invention. Detailed Implementation

[0071] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The specific embodiments described herein are merely used to explain the present invention and are not intended to limit the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0072] This invention provides a lightweight femtosecond pulsed waveguide fabrication process, aiming to utilize the ultrashort pulse characteristics of femtosecond lasers to generate local refractive index changes within transparent dielectric materials, thereby forming high-quality waveguide structures. This process achieves flexible design and efficient fabrication of the waveguide path through precise control of the femtosecond laser's pulse energy, repetition frequency, and scanning speed. Details are as follows:

[0073] like Figure 1 As shown, a lightweight femtosecond pulse waveguide forming process in this embodiment includes the following steps:

[0074] S1: Provide a transparent dielectric material, which has good light transmittance and can withstand the action of femtosecond laser; further including the following sub-processes:

[0075] S11 selects the type of transparent dielectric material, ensuring that the material's refractive index n meets the specific application requirements. To ensure good light transmittance and withstand the effects of femtosecond lasers, a material with a refractive index between 1.4 and 1.6 can be selected. Commonly used materials include quartz glass and silicon-based materials. Choosing a material with a refractive index between 1.4 and 1.6 ensures good light transmittance while also being able to withstand the effects of femtosecond lasers, preventing damage to the material during processing.

[0076] S12 Measurement Steps S11 Select the initial absorption coefficient α of the material o And calculate the absorption enhancement factor F = exp(α) of the material under femtosecond laser irradiation. o The process involves determining the laser penetration depth (L), where L represents the laser penetration depth. Specifically, after selecting a material, a high-precision spectrometer is used to measure its initial absorption coefficient. The absorption coefficient reflects the material's ability to absorb light. Next, the absorption enhancement factor of the material under femtosecond laser irradiation is calculated. The absorption enhancement factor refers to the increase in the absorption coefficient due to nonlinear absorption effects under femtosecond laser irradiation. The laser penetration depth refers to the effective depth of the laser's action within the material.

[0077] By measuring the initial absorption coefficient and calculating the absorption enhancement factor, the response characteristics of materials to femtosecond lasers can be accurately evaluated, providing a scientific basis for subsequent laser parameter adjustments and ensuring that materials are not damaged due to excessive absorption during processing.

[0078] S13, based on the absorption enhancement factor F in step S12, adjusts the laser's output power P to minimize the thermal effects generated within the material. The calculation formula is P. adj =P initial / F, where P initial This represents the initial output power of the laser.

[0079] Specifically, based on the absorption enhancement factor calculated in step S12, the output power of the femtosecond laser is adjusted. The aim is to minimize the thermal effects generated within the material, preventing irreversible damage due to overheating. By adjusting the laser's output power, it is ensured that the material can stably withstand the laser's influence during processing. Adjusting the laser's output power effectively reduces internal thermal effects within the material, preventing damage due to overheating, thereby improving the quality and stability of waveguide forming.

[0080] S14 utilizes the laser output power P adjusted in step S13. adj The selected transparent medium material is pretreated to verify its response characteristics to femtosecond lasers, ensuring that the material can withstand laser action stably without irreversible damage.

[0081] Specifically, the selected transparent medium material is pretreated using the laser output power adjusted in step S13. The purpose of the pretreatment is to verify the material's response characteristics to the femtosecond laser, ensuring that the material can stably withstand the laser's action during actual processing without irreversible damage. During the pretreatment process, the material's response characteristics can be evaluated by observing changes on the material surface and measuring the material's physical properties.

[0082] Preprocessing can reveal the material's response characteristics to femtosecond lasers in advance, ensuring that the material can stably withstand laser action during actual processing, avoiding processing failures due to material property mismatch, and improving the success rate and quality of waveguide forming.

[0083] By selecting suitable transparent dielectric materials, measuring and calculating the absorption characteristics of the materials, adjusting the output power of the laser, and performing pre-processing, it is possible to ensure that the materials can withstand processing stably under the action of femtosecond lasers, avoiding damage, thereby improving the quality and reliability of waveguide forming.

[0084] S2: Determine the waveguide forming area on the material provided in step S1, and calculate the position sequence of the laser focusing point based on the required waveguide shape and size; further including the following sub-processes:

[0085] S21 defines the boundary conditions of the waveguide shaping region and defines the starting point P of the waveguide. s and termination point P e This step involves defining the start and end points of the waveguide, as well as its general orientation within the material, thus providing a foundation for subsequent detailed design. By clearly defining the waveguide's start and end points and its centerline path C, it's possible to ensure the waveguide design meets practical application requirements and avoid path deviations or discontinuities during subsequent fabrication.

[0086] Based on the path C defined in step S21, step S22 calculates the waveguide width W and height H, and determines the shape of the waveguide cross-section. Common waveguide cross-section shapes include rectangular and elliptical. The width and height of the waveguide should be rationally selected according to the actual application requirements and material properties to ensure that the waveguide has good transmission performance. By calculating the width and height of the waveguide and determining the cross-sectional shape, it can be ensured that the geometric dimensions of the waveguide after forming meet the design requirements, thereby improving the transmission efficiency and optical performance of the waveguide.

[0087] S23 Using the waveguide cross-section shape determined in step S22, and combined with the waveguide centerline path C, calculate the laser focal point position sequence S = {S1, S2, ..., S...} n}, where each location point S i Uniformly distributed along path C with a spacing of d, the calculation formula is as follows: Where N represents the total number of focal points; the purpose of this step is to ensure that when the laser scans point by point within the material, it can uniformly cover the entire waveguide path, forming a continuous waveguide structure. By calculating the position sequence of the laser focal points, it is possible to ensure that the laser scanning path within the material is uniformly distributed, avoiding problems such as discontinuities in the waveguide structure or increased transmission loss caused by uneven spacing between focal points.

[0088] Step S24 optimizes the position sequence S obtained in step S23, checking whether the distance between adjacent focal points is uniform. If non-uniformity is found, the number of focal points N is adjusted or the spacing d is recalculated to ensure that the distance between all focal points meets the design requirements. By optimizing the position sequence, it is possible to ensure that the distance between all focal points is uniformly distributed, avoiding waveguide structure defects caused by uneven focal point spacing, and improving the geometric accuracy and transmission performance of the waveguide.

[0089] By determining the boundary conditions of the waveguide forming region, calculating the width and height of the waveguide, calculating the position sequence of the laser focusing point, and optimizing the position sequence, it is possible to ensure that the geometric dimensions and transmission performance of the waveguide after forming meet the design requirements, thereby improving the forming quality and reliability of the waveguide.

[0090] S3: Based on the position sequence determined in step S2, adjust the operating parameters of the femtosecond laser and set an appropriate pulse energy to ensure that a local refractive index change is generated within the material without damaging the material structure; this further includes the following sub-processes:

[0091] S31 calculates the total number of pulses M required for waveguide shaping based on the laser focal point position sequence determined in step S2, where M equals the number of focal points in the position sequence. The purpose of this step is to determine the total number of pulses required throughout the waveguide shaping process, providing a basis for subsequent parameter adjustments. By calculating the total number of pulses, it can be ensured that the number of laser pulses matches the designed number of focal points during waveguide shaping, avoiding incomplete waveguide structure or material damage due to insufficient or excessive pulse counts.

[0092] S32 estimates the energy range of a single pulse based on the total number of pulses M calculated in step S31, ensuring that the total energy does not exceed the material's damage threshold. The calculation formula is as follows: Where E th This step determines the damage threshold energy of the material. The purpose of this step is to ensure that the energy of each pulse is within a reasonable range, preventing material damage due to excessive total energy. By estimating the energy range of a single pulse, it can be ensured that the energy of each pulse during waveguide forming does not exceed the material's damage threshold, avoiding irreversible damage due to excessive energy and improving the reliability of waveguide forming.

[0093] S33 considers the energy accumulation effect during waveguide shaping and adjusts the energy E of a single pulse to make it within the range of E. min and E max Between. The calculation formula is: Where E min To ensure the minimum energy required for refractive index change, this step aims to minimize energy accumulation and prevent localized overheating of the material while maintaining the desired refractive index change. By adjusting the energy of each pulse, it can be ensured that during waveguide forming, the energy of each pulse is sufficient to generate the required local refractive index change without causing localized overheating due to energy accumulation, thus improving the quality and stability of waveguide forming.

[0094] S34 applies the single pulse energy E determined in step S33 to the femtosecond laser, sets the laser's pulse energy parameters, and performs preliminary tests to verify whether the pulse energy can effectively produce a local refractive index change without damaging the material. Preliminary tests can be conducted by observing changes on the material surface and measuring the material's physical properties. The purpose of this step is to ensure that the laser's pulse energy is set correctly and can effectively achieve waveguide shaping.

[0095] By setting the pulse energy parameters of the laser and conducting preliminary tests, it is possible to verify whether the pulse energy setting is appropriate, ensuring that local refractive index changes can be effectively generated during actual processing without damaging the material, thereby improving the success rate and quality of waveguide forming.

[0096] By calculating the total number of pulses required for waveguide forming, estimating the energy range of a single pulse, adjusting the energy of a single pulse, and setting the pulse energy parameters of the laser, it can be ensured that during waveguide forming, the pulse energy of the laser can both generate the required local refractive index change within the material and not exceed the material's damage threshold.

[0097] S4: Using the parameters set in step S3, start the femtosecond laser and scan point by point inside the material along the path planned in step S2 to form the initial waveguide profile; this further includes the following sub-processes:

[0098] S41 initializes the operating parameters of the femtosecond laser based on the pulse energy E and total number of pulses M set in step S3, ensuring stable output pulse energy. The purpose of this step is to ensure that the laser can continuously output stable pulse energy during operation, providing reliable energy support for subsequent waveguide forming. By initializing the operating parameters of the femtosecond laser, stable pulse energy output during waveguide forming can be ensured, avoiding waveguide structural inhomogeneity or material damage caused by energy fluctuations, thus improving the stability and reliability of waveguide forming.

[0099] S42, based on the laser focal point position sequence determined in step S2, sets the laser scanning path, causing the laser to scan point by point along the path, one focal point at a time. The total length L of the scanning path is calculated. total ,in S i S represents the position of the i-th focal point; i+1 The position of the (i+1)th focal point is defined. By setting the scanning path of the laser, it can be ensured that the laser scans point by point within the material along a predetermined path, forming a continuous and accurate waveguide profile, thus avoiding problems such as discontinuity in the waveguide structure or increased transmission loss due to path deviation.

[0100] S43 determines the laser scanning speed v to ensure that the laser interaction time at each focal point is sufficient to produce the required refractive index change. The calculation formula is as follows: Where t total The total scanning time can be set based on material properties and experimental experience. By determining an appropriate laser scanning speed, it is possible to ensure that the laser action time at each focal point is sufficient, avoiding insufficient refractive index change due to excessively fast scanning speed or overheating of the material due to excessively slow scanning speed, thereby improving the quality and stability of waveguide forming.

[0101] In step S44, the femtosecond laser is activated, and scanning is performed point-by-point according to the scanning speed v set in step S43 and the path set in step S42 to form the initial waveguide profile. The laser power and positional deviation during the scanning process are monitored in real time to ensure scanning accuracy and stability. By monitoring the laser power and positional deviation in real time, any deviations during the scanning process can be detected and corrected promptly, ensuring the accuracy and stability of the scanning process, thereby improving the quality and reliability of waveguide formation.

[0102] By initializing the operating parameters of the femtosecond laser, setting the laser scanning path, determining the laser scanning speed, and starting the femtosecond laser to scan, it can be ensured that the laser can stably output pulse energy during the waveguide forming process, accurately scan point by point along the predetermined path, and form a high-quality initial waveguide profile.

[0103] S5: Perform quality inspection on the initial waveguide profile formed in step S4 to evaluate the waveguide's transmission loss and geometric accuracy; this further includes the following sub-processes:

[0104] S51 uses a high-precision optical microscope to check the geometric accuracy of the initial waveguide formed in step S4, records the deviations Δx and Δy between the actual waveguide path and the designed path, and calculates the geometric accuracy error. By using a high-precision optical microscope to perform geometric accuracy testing, the deviation between the actual path and the designed path of the waveguide can be accurately recorded, the geometric accuracy error can be calculated, and the geometric accuracy of the waveguide can be ensured to meet the design requirements, thus avoiding increased transmission loss or signal distortion caused by path deviation.

[0105] S52 is based on the geometric accuracy error ε detected in step S51. geom To assess whether the waveguide's geometric accuracy meets the design requirements, if the error exceeds a preset threshold ε... max If the geometric accuracy error is not correct, the laser scanning parameters need to be adjusted and the waveguide re-formed. By evaluating the geometric accuracy error, geometric deviations in the waveguide forming process can be detected in a timely manner, and necessary adjustment measures can be taken to ensure that the geometric accuracy of the waveguide meets the design requirements, thereby improving the transmission performance and reliability of the waveguide.

[0106] The S53 uses a spectrum analyzer to measure the waveguide's transmission loss by inputting optical power P. in and output optical power P out Calculate transmission loss By measuring transmission loss using a spectral analyzer, the transmission performance of waveguides can be accurately evaluated, ensuring that the transmission loss of optical signals in the waveguides meets design requirements and avoiding signal attenuation or communication quality problems caused by excessive transmission loss.

[0107] S54 will take the transmission loss L measured in step S53. transWith respect to the required transmission loss threshold L max By comparing the transmission loss, if it exceeds the threshold, the laser's pulse energy or scanning speed needs to be optimized, and the waveguide shaping process needs to be redone. By evaluating the transmission loss, transmission loss problems during the waveguide shaping process can be identified in a timely manner, allowing for necessary optimization measures to ensure that the waveguide's transmission loss meets design requirements and improves its transmission performance and reliability.

[0108] By using a high-precision optical microscope to detect and evaluate geometric accuracy, and by using a spectral analyzer to measure and evaluate transmission loss, it can be ensured that the geometric accuracy and transmission loss of the waveguide meet the design requirements during the waveguide forming process, thus avoiding performance problems caused by geometric deviations or excessive transmission loss.

[0109] S6: If the quality inspection result of step S5 does not meet the preset standard, then fine-tune the operating parameters of the femtosecond laser in step S3 according to the inspection result, and optimize the pulse energy or repetition frequency of the femtosecond laser; further including the following sub-processes:

[0110] S61 Based on the geometric accuracy error ε detected in step S5 geom and transmission loss L trans The waveguide quality is then assessed to determine if it meets the preset standard. If the geometric accuracy error exceeds the threshold ε, the waveguide quality is assessed. max Or the transmission loss exceeds the threshold L max Then proceed to the next step; by judging the geometric accuracy error and transmission loss of the waveguide, quality problems in the waveguide forming process can be detected in time, providing a basis for subsequent parameter optimization and ensuring that the waveguide performance meets the design requirements.

[0111] In step S62, analyze the specific problems with the detection results in step S5 to determine the parameters that need optimization. If the main problem is excessive geometric accuracy error, adjust the laser scanning speed v and calculate the new scanning speed. The purpose of this step is to determine the parameters that need optimization based on the specific test results, so that targeted adjustments can be made. By analyzing the test results, the main problems in the waveguide forming process can be accurately identified, providing a clear direction for subsequent parameter optimization and improving the accuracy and reliability of waveguide forming.

[0112] If the main problem is excessive transmission loss, then adjust the laser pulse energy E and calculate the new pulse energy. By adjusting the laser pulse energy, transmission loss can be effectively reduced, waveguide transmission performance can be improved, and the transmission loss of optical signals in the waveguide can be kept within an acceptable range.

[0113] S64 applies the adjusted parameters from step S62 or S63 to the femtosecond laser, and re-executes steps S4 to S5 until the waveguide quality test results meet the preset standards. By re-executing waveguide forming and quality testing, it can be ensured that the geometric accuracy and transmission loss of the waveguide reach the preset standards after multiple adjustments, avoiding waveguide quality problems caused by improper parameter settings, and improving the reliability and success rate of waveguide forming.

[0114] S7: Re-execute step S4 according to the parameters adjusted in step S6 until the waveguide's transmission loss and geometric accuracy meet the requirements; this further includes the following sub-processes:

[0115] S71 reinitializes the pulse energy E of the femtosecond laser based on the laser operating parameters adjusted in step S6. new and scanning speed v new By reinitializing the operating parameters of the femtosecond laser, it is possible to ensure that the laser can operate stably under the new parameter settings, avoid waveguide quality problems caused by improper parameter settings, and improve the accuracy and reliability of waveguide forming.

[0116] S72 uses the parameters set in step S71 to re-execute the laser scanning process in step S4, so that the laser scans point by point inside the material along the path planned in step S2 to form a new waveguide profile. By re-executing the laser scanning process, it can be ensured that the new parameter settings are effectively applied in the actual waveguide forming process, forming a high-quality waveguide profile and improving the transmission performance and geometric accuracy of the waveguide.

[0117] After completing the scan in step S72, step S73 performs the quality check in step S5 again to evaluate the transmission loss L of the new waveguide. trans and geometric accuracy error ε geom By performing quality checks again, it can be verified whether the new parameter settings have effectively solved the previous quality problems, ensuring that the geometric accuracy and transmission loss of the waveguide reach the preset standards after multiple adjustments, thereby improving the reliability and success rate of waveguide forming.

[0118] S74 compares the transmission loss L measured in step S73. trans and geometric accuracy error ε geom Compared with the preset standard value L max and ε max If the requirements are still not met, return to step S6 to continue adjusting the parameters until the waveguide quality meets the requirements. By comparing the test results with the preset standards, quality problems in the waveguide forming process can be identified in a timely manner, and necessary adjustment measures can be taken to ensure that the geometric accuracy and transmission loss of the waveguide ultimately meet the design requirements, thereby improving the transmission performance and reliability of the waveguide.

[0119] By re-initializing the operating parameters of the femtosecond laser, re-executing the laser scanning process, re-performing the quality inspection, and comparing the inspection results with the preset standards, it can be ensured that the geometric accuracy and transmission loss of the waveguide ultimately meet the design requirements after multiple adjustments during the waveguide forming process.

[0120] S8: After waveguide forming is completed, the material undergoes surface treatment to remove any minor defects that may be caused by laser action, thereby improving the overall performance of the waveguide; this further includes the following sub-processes:

[0121] S81 uses a high-resolution optical microscope to perform a detailed inspection of the material surface after waveguide forming, identify and mark the tiny defect areas caused by laser action, denoted as the defect point set D; by using a high-resolution optical microscope for detailed inspection, the tiny defects on the material surface can be accurately identified, ensuring that these defects can be removed in a targeted manner in subsequent processing, thereby improving the overall performance of the waveguide.

[0122] S82 calculates the area A of each defect point based on the set D of defect points identified in step S81. i and depth d i These parameters are recorded; by calculating the area and depth of each defect point, the nature of the defect can be understood in detail, providing accurate data support for subsequent surface treatment and ensuring the effectiveness and specificity of the treatment method.

[0123] S83 Select an appropriate surface treatment method, such as chemical polishing or mechanical grinding, and calculate the treatment parameters based on the defect point parameters recorded in step S82. For chemical polishing, calculate the polishing solution concentration C and the treatment time t, using the formula C = k1·max(A i ) and t = k2·max(d i ), where k1 and k2 are empirical constants, and max represents the maximum value; by selecting appropriate surface treatment methods and calculating processing parameters, the effectiveness and accuracy of the surface treatment process can be ensured, new defects or material damage caused by improper treatment can be avoided, and the overall performance of the waveguide can be improved.

[0124] S84 applies the processing parameters determined in step S83 to treat the material surface, remove defects, and then re-examines the surface using an optical microscope to ensure that all defects have been effectively removed. By performing surface treatment and re-examining the surface, it is ensured that all defects are effectively removed, improving the surface quality and overall performance of the waveguide, avoiding increased transmission loss or signal distortion caused by surface defects, and ensuring the reliability and transmission performance of the waveguide.

[0125] S9: Perform a final inspection on the waveguide processed in step S8 to confirm that all waveguide parameters meet design requirements, thus completing the waveguide forming process. This further includes the following sub-processes:

[0126] S91 uses a high-precision optical microscope to perform a final inspection of the waveguide surface processed in step S8, and records the surface roughness parameter R, calculated using the following formula: Where h j The height h of each measurement point avg N is the average height of all measurement points. s The number of measurement points; by using a high-precision optical microscope for final inspection, the roughness parameters of the waveguide surface can be accurately recorded, ensuring that the waveguide surface is smooth after surface treatment and avoiding increased transmission loss or signal distortion caused by surface roughness.

[0127] S92 evaluates whether the roughness of the waveguide surface meets the design requirements based on the roughness parameter R measured in step S91. If the roughness parameter exceeds a preset threshold R... thresh If the surface treatment in step S8 is not satisfactory, the surface treatment needs to be repeated. By evaluating the roughness of the waveguide surface, problems in the surface treatment can be identified in a timely manner, and necessary adjustment measures can be taken to ensure that the roughness of the waveguide surface meets the design requirements, thereby improving the transmission performance and reliability of the waveguide.

[0128] The S93 uses a spectral analyzer to measure the final transmission loss of the waveguide, by inputting optical power P. input and output optical power P output Calculate the final transmission loss Among them, log 10 This represents the logarithm to base 10, also known as the common logarithm. The transmission loss is then compared with the data from step S5 to ensure that the transmission loss has not deteriorated due to surface treatment. By measuring the final transmission loss and comparing it with previous test results, it can be ensured that the surface treatment process has not introduced new transmission loss, guaranteeing that the waveguide's transmission performance meets design requirements and avoiding performance degradation caused by surface treatment.

[0129] S94 integrates the test results from steps S91 to S93 to confirm that all indicators of the waveguide meet the design requirements, including surface roughness, transmission loss, and geometric accuracy, thus completing the waveguide forming process. By comprehensively evaluating the various indicators of the waveguide, it can be ensured that the waveguide's performance in multiple aspects meets the design requirements, avoiding overall performance problems caused by substandard performance in one aspect, and improving the reliability and transmission performance of the waveguide.

[0130] By conducting a final inspection of waveguide surface roughness, evaluating surface roughness, measuring final transmission loss, and comprehensively assessing waveguide parameters, it can be ensured that all performance indicators of the waveguide meet design requirements during the waveguide forming process, avoiding performance problems caused by surface treatment or other factors. These measures effectively improve the quality and reliability of waveguide forming, ensuring that the waveguide's transmission performance and geometric accuracy meet design requirements.

[0131] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A lightweight femtosecond pulse waveguide forming process, characterized in that, Includes the following steps: S1: Provide a transparent dielectric material, which has good light transmittance and can withstand the effects of femtosecond lasers, specifically including: S11: Selecting the type of transparent dielectric material to ensure the refractive index of the material. To meet the requirements, the refractive index It should be greater than 1.4 and less than 1.6; S12: Measurement step S11 selects the initial absorption coefficient of the material. And calculate the absorption enhancement factor of the material under femtosecond laser irradiation. ,in S13: Laser penetration depth; S14: Absorption enhancement factor based on step S12 Adjust the output power of the laser This minimizes the thermal effects generated inside the material, and the calculation formula is: ,in S14: Initial output power of the laser; S15: Laser output power adjusted using step S13 The selected transparent medium material is pretreated; S2: Determine the path of the waveguide forming region on the material provided in step S1, and calculate the position sequence of the laser focusing point based on the required waveguide shape and size; S3: Based on the position sequence determined in step S2, adjust the operating parameters of the femtosecond laser and set the pulse energy to ensure that a local refractive index change is generated inside the material without damaging the material structure; S4: Using the working parameters set in step S3, start the femtosecond laser and make the laser scan point by point inside the material along the path of the waveguide forming area planned in step S2 to form the initial waveguide profile. S5: Perform quality inspection on the initial waveguide profile formed in step S4 to evaluate the waveguide's transmission loss and geometric accuracy; S6: If the quality inspection result of step S5 does not meet the preset standard, then adjust the working parameters of the femtosecond laser in step S3 according to the inspection result, and optimize the pulse energy or repetition frequency of the femtosecond laser. S7: Re-execute step S4 according to the parameters adjusted in step S6 until the waveguide's transmission loss and geometric accuracy meet the requirements. S8: After the waveguide forming area is formed, the material is surface treated to remove the minute defects caused by the laser action and improve the overall performance of the waveguide. S9: Perform a final inspection on the waveguide forming area processed in step S8 to confirm that all indicators of the waveguide forming area meet the design requirements, and complete the waveguide forming process.

2. The lightweight femtosecond pulse waveguide forming process according to claim 1, characterized in that, Step S2 includes the following sub-processes: S21: Determine the boundary conditions of the waveguide shaping region and define the starting point of the waveguide. and termination point and the centerline path of the waveguide ; S22: Based on the path defined in step S21 Calculate waveguide width and height And determine the shape of the waveguide cross section; S23: Using the shape of the waveguide cross-section determined in step S22, combined with the waveguide centerline path Calculate the position sequence of the laser focal point. ,in For each location point, along the path Evenly distributed, with a spacing of The calculation formula is: ,in The total number of focal points; S24: The position sequence obtained in step S23 Optimize by checking if the distance between adjacent focal points is uniform. If non-uniformity is found, adjust the number of focal points. Or recalculate the spacing .

3. The lightweight femtosecond pulse waveguide forming process according to claim 2, characterized in that, Step S3 includes the following sub-processes: S31: Based on the laser focal point position sequence determined in step S2, calculate the total number of pulses required for waveguide shaping. ,in It equals the number of focal points in the position sequence; S32: Total number of pulses calculated based on step S31 Estimate the energy range of a single pulse to ensure that the total energy does not exceed the material's damage threshold. The calculation formula is as follows: ,in The damage threshold energy of the material; S33: Considering the energy accumulation effect during waveguide shaping, adjust the energy of a single pulse. The energy of a single pulse exist and Between, the calculation formula is ,in To ensure the minimum energy required for a change in refractive index; S34: The single pulse energy determined in step S33 Applied to femtosecond lasers, the pulse energy parameters of the laser are set, and preliminary tests are conducted to verify whether the pulse energy can effectively produce local refractive index changes without damaging the material.

4. The lightweight femtosecond pulse waveguide forming process according to claim 3, characterized in that, Step S4 includes the following sub-processes: S41: Based on the pulse energy set in step S3 Total number of pulses Initialize the operating parameters of the femtosecond laser; S42: Based on the position sequence of the laser focal points determined in step S2, set the scanning path of the laser, and scan the laser point by point along the path, scanning one focal point at a time, and calculate the total length of the scanning path. ,in , For the The location of the focal point; S43: Determine the laser scanning speed To ensure that the laser interaction time at each focal point is sufficient to produce the required refractive index change, the calculation formula is as follows: ,in Total scan time; S44: Start the femtosecond laser and scan at the speed set in step S43. The laser power and position deviation during the scanning process are monitored in real time, and the path set in step S42 is scanned point by point to form the initial waveguide profile.

5. The lightweight femtosecond pulse waveguide forming process according to claim 4, characterized in that, Step S5 includes the following sub-processes: S51: Use a high-precision optical microscope to check the geometric accuracy of the initial waveguide formed in step S4, and record the deviation in the x-direction between the actual waveguide path and the designed path. Deviation in the y-direction Calculate geometric accuracy error ; S52: Based on the geometric accuracy error detected in step S51 The waveguide's geometric accuracy is evaluated to determine if it meets design requirements; if the error exceeds a preset threshold. If so, the laser scanning parameters need to be adjusted and the waveguide reshaped. S53: Measure the waveguide transmission loss using a spectral analyzer by inputting optical power. and output optical power Calculate transmission loss ; S54: The transmission loss measured in step S53 Transmission loss threshold required by design Comparison: If the transmission loss exceeds the transmission loss threshold... If so, it is necessary to optimize the laser's pulse energy or scanning speed and reshape the waveguide.

6. The lightweight femtosecond pulse waveguide forming process according to claim 5, characterized in that, Step S6 includes the following sub-processes: S61: Based on the geometric accuracy error detected in step S5 and transmission loss To determine whether the waveguide quality meets the preset standard, if the geometric accuracy error exceeds the threshold... Or transmission loss exceeds the threshold Then proceed to the next step; S62: Analyze the problems in the detection results of step S5, determine the parameters that need to be optimized, and if the main problem is that the geometric accuracy error is too large, then adjust the laser scanning speed. Calculate the new scan speed ; S63: If the main problem is excessive transmission loss, adjust the laser pulse energy. Calculate the new pulse energy ; S64: Apply the adjusted parameters from step S62 or step S63 to the femtosecond laser, and repeat steps S4 to S5 until the waveguide quality test results meet the preset standards.

7. The lightweight femtosecond pulse waveguide forming process according to claim 6, characterized in that, Step S7 includes the following sub-processes: S71: Reinitialize the pulse energy of the femtosecond laser based on the laser operating parameters adjusted in step S6. and scanning speed ; S72: Using the parameters set in step S71, re-execute the laser scanning process in step S4, so that the laser scans point by point inside the material along the path planned in step S2 to form a new waveguide profile. S73: After completing the scan in step S72, perform the quality check in step S5 again to evaluate the transmission loss of the new waveguide. and geometric accuracy error ; S74: Compare the transmission loss measured in step S73. and geometric accuracy error Compared with the preset standard value and If the requirements are still not met, return to step S6 to continue adjusting the parameters until the waveguide quality meets the requirements.

8. The lightweight femtosecond pulse waveguide forming process according to claim 7, characterized in that, Step S8 includes the following sub-processes: S81: A high-resolution optical microscope is used to perform a detailed inspection of the material surface after waveguide forming, identifying and marking the tiny defect areas caused by laser action, which are recorded as a set of defect points. ; S82: Based on the set of defect points identified in step S81 Calculate the area of ​​each defect point. and depth And record these parameters; S83: Based on the defect point parameters recorded in step S82, calculate the processing parameters. For chemical polishing, calculate the polishing solution concentration. and processing time The formula is and ,in and These are empirical constants; S84: Apply the processing parameters determined in step S83 to process the material surface, remove defects, and then re-examine the surface using an optical microscope.

9. The lightweight femtosecond pulse waveguide forming process according to claim 8, characterized in that, Step S9 includes the following sub-processes: S91: Perform a final inspection of the waveguide surface processed in step S8 using an optical microscope, and record the surface roughness parameter R. The calculation formula is as follows: ,in The height of each measurement point The average height of all measurement points. The number of measurement points; S92: Based on the roughness parameters measured in step S91 The surface roughness of the waveguide is evaluated to determine if it meets design requirements. If the roughness parameter exceeds a preset threshold... If so, the surface treatment in step S8 needs to be repeated; S93: Measure the final transmission loss of the waveguide using a spectral analyzer, by inputting optical power. and output optical power Calculate the final transmission loss And compare it with the data in step S5 to ensure that the transmission loss has not worsened due to the surface treatment; S94: Based on the test results from steps S91 to S93, confirm that all indicators of the waveguide meet the design requirements and complete the waveguide forming process.

Images