This PDF file contains the front matter associated with SPIE Proceedings Volume 12307 including the Title Page, Copyright information, and Table of Contents.

This study is based on near-infrared spectroscopic detection technology to achieve 100% classification of in-class and out-of-class pharmaceutical ingredients and excipients by support vector machine model.4 types of 8 different pharmaceutical excipients (starches: corn starch, potato starch, sweet potato starch, pregelatinized starch, maltodextrin, lactose: lactose monohydrate, Cellulose: microcrystalline cellulose, phosphate: magnesium stearate) are collected by near-infrared spectrometer, 150 sets of spectral data each. A total of 1200 spectra are used, 840 spectra of which are randomly divided as the training set and 360 as the validation set. Compare the effects of models built by Bayesian algorithm, support vector machine algorithm, and K-nearest neighbor algorithm paired with first-order difference, second-order difference, MSC, and SNV preprocessing, respectively. The results show that both Bayesian and K-nearest neighbor algorithms achieve 100% out-of-class resolution when paired with first-order difference, MSC, and SG smoothing preprocessing methods, In contrast, the support vector machine achieves 100% classification accuracy without any preprocessing, and the accuracy is not reduced after dimensionality reduction by the competitive adaptive reweighting algorithm. Finally, this experiment achieves 100% accuracy of in-class and out-of-class classification of 8 APIs in 4 classes by NIR spectroscopy combined with support vector machine algorithm model, and the CARS algorithm is used for data dimensionality reduction to simplify the model.

The dark spots in the speckle pattern are the phase singularities, which contain rich information regarding the phase of the speckle field and determine the distribution of the speckle field. The generation of optical vortices using speckle is a simple, effective, and easy to implement method. we designed an experimental scheme that can generate a optical vortex to explain the properties of phase singularities in a speckle field. Through numerical simulation, we obtained the distribution of the real part zero line and the imaginary part zero line in the speckle field, and drew the singular skeleton of the speckle field, indicating that there are phase singularities in the speckle field.The experimental results are in agreement with those obtained from numerical simulations, thus verifying that the generation of optical vortices can be produced using the scattering method. The experimental scheme is simple and easy to operate.

We demonstrated a wavelength tunable mode-locked optically pumped semiconductor disk laser (OP-SDL) based on a SESAM. The wavelength tuning is achieved by incorporating an uncoated, 100 μm thick, fused silica etalon into the cavity of the laser, and the central wavelength of the pulse train varied from 972 nm to 977 nm. The average power of the mode-locked states measured at different wavelengths was about 80mW, meanwhile, the repetition rate was 1.2 GHz in the tuning process, and the signal-to-noise ratio of the radio frequency spectrum signal exceeds 50 dB, which illustrates that the laser can maintain a stable mode-locked state even the central wavelength varies greatly. In addition, we calculated the influence of etalon's related parameters on its transmittance. This research contributes to the development of wavelength-tunable mode-locked OP-SDLs and to gain practical applications in related fields.

To meet the specific needs or improve the system’s energy efficiency, it is necessary to integrate the beam into a specific intensity distribution beam. This paper establishes a set of rules based on the mixed-region amplitude freedom (MRAF) algorithm, and a beam shaping algorithm is proposed to calculate the intensity distribution by setting the energy efficiency. Simulation results show that compared with the traditional Gerchberg–Saxton (GS) algorithm, the convergence effect improved by one to two orders of magnitude after abandoning controlling a small part of the energy; compared with the MRAF algorithm, the energy efficiency converged to the preset target value, in addition, the energy efficiency is higher under the same convergence intensity. This algorithm provides a new path for shaping in femtosecond laser processing technology.

Taking advantage of the technology of dispersive Fourier transform (DFT), we experimentally observed the evolutionary dynamics of convention solitons(CSs) in a simplified Erbium-doped fiber laser. The periodic beating behavior that occurs during the build-up and disappearance of conventional solitons was discovered in a nonlinear polarization rotation (NPR) fiber lasers. We suggest the reasonable assumption that the periodic beating during the dynamic evolution may be a close connection with the modulation depth of the intracavity saturable absorber The results of this study can deepen researchers' understanding of the evolution of CSs and provide additional judgment dimensions for optimizing the laser parameters.

The synchronization of ultrashort pulses is an important research content in laser technology and has important applications in the fields of pump probe, optical frequency metrology, optical coherent synthesis, and nonlinear optics, etc. In this paper, the mode locking of two Yb-doped fiber lasers is realized by nonlinear polarization rotation, and then two circulators are used to make both two laser beams propagate in a piece of fiber. By matching the cavity length of one laser to the other, and with the cross phase modulation of two laser beams in the shared single-mode fiber, two lasers are passively synchronized. Two lasers deliver picosecond pulses near 1.04 μm and 1.05 μm, respectively, and the repetition rate is locked around 38.1100 MHz.

The spectral sensitivity function of a digital camera is an important parameter and the recovery of camera spectral sensitivity function is a crucial study. In this paper, we propose a new rank-based constraint algorithm to estimate the spectral sensitivity. The constraints are imposed on the estimation of the spectral sensitivity based on the rank orders of the response values of the digital camera for imaging standard color samples under different illuminations. Color samples and illuminations are known in the estimation process. We have two kinds of ranking constraints in the algorithm, one is ranking under a single illumination, and the other is ranking under multiple illuminations. Besides, with the support of two ranking constraints, we use fewer color samples in the experiments. The study is evaluated by several numerical simulation experiments and compared with other spectral sensitivity estimation algorithms. We added various levels of noise and tried various combinations of multiple illuminations to recover the spectral sensitivity of different cameras. The experimental results suggest that the proposed algorithm performs better in estimating the camera spectral sensitivity function and computational work is reduced. At the same time, utilizing fewer color samples can reduce the complexity of the experiment without increasing the experimental error metric.

Taking advantage of the technology of dispersive Fourier transform (DFT), we experimentally observed the evolutionary dynamics of convention solitons(CSs) in a simplified Erbium-doped fiber laser. The periodic beating behavior that occurs during the build-up and disappearance of conventional solitons was discovered in a nonlinear polarization rotation (NPR) fiber lasers. We suggest the reasonable assumption that the periodic beating during the dynamic evolution may be a close connection with the modulation depth of the intracavity saturable absorber The results of this study can deepen researchers' understanding of the evolution of CSs and provide additional judgment dimensions for optimizing the laser parameters.

In this paper, an optimized structure of single photon avalanche diode (SPAD) with p-i-n construction is presented, and the device is compatible with standard CMOS technology. TCAD software and accurate calculation method based on physics mechanism are employed for the device structure design and DCR calculation, respectively. The characteristic parameters of the device, such as electric field and electron and hole triggering probability, are available through TCAD Atlas device simulation. The central region of P-sub doping is designed as a part of avalanche region, which achieves a lower electric field, and makes the band-to-band tunneling suppressed simultaneously. The breakdown voltage of the SPAD is 38.5 V. At excess bias voltage of 5 V, DCR is 0.88 Hz/μm2 at room temperature. The maximum electric field of the optimized structure is 3.8×105 V/cm. As for PDE, at room temperature with 5.0 V excess bias, the PDE is greater than 30% in the 400 nm-675 nm range, with a peak PDE of 40% at 550 nm. At 850 nm, there is still a photon detection efficiency of more than 10%, making the SPAD still have a certain detection capability. The superior performance of this structure makes it suitable for wide applications.

Aiming at the problem of low initial accuracy of AGV after steering, we design a vehicle steering control algorithm based on an improved pure tracking model. Firstly, in order to improve the adaptive ability of the pure tracking model, we estimate the look-ahead distance of the pure tracking model in real time through the PSO algorithm. We use the IWO algorithm to optimize the ability of the particle swarm finding fitness, so as to avoid the particle swarm easily falling into local convergence during the working process. Secondly, in order to meet the requirements of the improved pure tracking model for continuous curvature, we add an easing curve to the traditional fishtail U-turn trajectory, and design a non-tangential round fishtail U-turn. Finally, we carry out a simulation test of the algorithm. The test results show that: using the IWO-PSO-PTM algorithm, when the vehicle speed is 0.75m/s for U-turn, the maximum lateral error is less than 0.42m, and the root mean square error is 0.18m. And when the straight line travel distance exceeds 4m after line change, the maximum lateral error is less than 0.02m. The pure tracking algorithm improved by IWO-PSO can effectively improve the initial accuracy of the AGV after steering.

Metasurface is a kind of functional device based on assemblies of subwavelength structures, which can perform multiple operations on light modulation, such as phase, amplitude and polarization modulation. However, due to the difficulty of design and high processing cost of three-dimensional nano-structure, it is far from practical applications. In this paper, we propose a method to replicate the metasurface structure at room temperature using Nanoimprint Lithography (NIL), the process including: use electron beam lithography to fabricate metasurface structure as the master for NIL; transfer the inverse structure of metasurface onto the PET substrate as the working NIL stamp; imprint the metasurface structure into proper UV resist as the metasurface holographic substrate. The imprinted metasurface structure was characterized by SEM, and the image information recorded inside the metasurface structure was reproduced by laser illumination, which proved the effectiveness of the proposed method.

Er,Yb co-doped glass has been widely used to generate 1.5-μm Q-switched pulsed lasers, which are in strong demands for such applications as remote sensing telemetry, LiDAR and imaging. Aiming to meet such demands, we developed a ultra-compact and lightweight diode-pumped solid-state laser, which can achieve a Q-switched pulse energy of 1.5 mJ at an eye-safe wavelength of 1534-nm with an optical conversion efficiency of 3.4% under pump power of 22 W in the operating frequency range of 1-10 Hz. In the experiment, a 940-nm semiconductor laser was used to pump an Er,Yb co-doped glass with a saturable absorber (Co2+:Spinel) to realize Q switching. A theoretical model was then developed to simulate and characterize the Er,Yb co-doped glass laser. The model takes into account not only the excited state absorption and up-conversion effects, but also the thermal effects on the laser. The simulation results are in high agreement with the experimental ones.

Circuit QED based on superconducting circuit structure is similar to the model of interaction between cavity field and atoms, and is solidified on the substrate, so it is more suitable for integration, expansion and control. The circuit QED system consists of resonators and superconducting qubits, the length of the resonators much larger than width, so it can be regarded as a one-dimensional linear planar structure in theory. We propose a theoretical model to realizing two-qubit photonic phase gate, we use two superconducting resonators to couple a magnetic flux qutrit via two capacitors in circuit QED system, and choose an appropriate interaction time, it turns out that a two-qubit photonic phase gate can be realized by one step.

Phase modulation can obtain the desired pattern by reshaping the light field in the focusing area of the objective lens, which has important application value in optical microscopic imaging, laser processing, optical tweezers and other fields.The traditional method is the GS algorithm (Gerchberg–Saxtonalgorithm). In the imaging system, GS algorithm can quickly calculate the phase distribution on the focal plane of the lens through the known intensity distribution of the Fourier domain. The GS algorithm is based on the paraxial approximation, and the phase distribution of the focal plane after the objective and the intensity distribution of the focal plane before the objective can be calculated by the Fourier Transformation (FT). However, in the case of objectives with high numerical aperture, FT cannot accurately describe the relationship between the phase distribution and the known light intensity distribution due to the strong depolarization effect, and can no longer accurately obtain the desired lattice pattern. To this end, based on Debye diffraction theory, this paper implements the generation of lattice patterns under a strongly focused light field. In order to calculate the phase distribution on the rear aperture of the objective lens and the light intensity distribution and phase information generated by the front focal plane of the objective lens, we replace the Fourier transform in the GS algorithm with the Debye diffraction integral. We used a digital pattern to verify the effectiveness of the method. The results show that the resulting lattice pattern is similar to the truth value, and the intensity of each point in the lattice is uniform. This method can realize the generation of arbitrary lattice patterns under the strongly focused light field, and further expand the use of light field modulation in biomedical optical imaging, laser processing, optical tweezers and other fields.

A localization method based on monocular vision is proposed to solve the problem of poor flexibility, high cost and unstable accuracy of glue dispensing robot. The method includes the workpiece image feature extraction method based on distribution model and the optimized PNP algorithm based on depth calibration, which can locate the threedimensional coordinates of the workpiece and further generate the gluing track. Firstly, the layout and local coordinates of feature points are determined according to the workpiece model and gluing process, and the feature distribution model and template set are established. Then the image coordinates of feature points are extracted step by step by using workpiece contour features and image gray features, combining multi template and multi angle matching with shape detection, and using acceleration strategies such as image pyramid and angle layer by layer subdivision. Finally, the PNP algorithm is optimized in the Z direction through the depth calibration method to realize the high-precision positioning of the workpiece. The localization experiments of various types of reducer shells under different imaging environments were carried out. The experimental results show that the method has better feature extraction effect for workpieces with complex structure in chaotic environment, and the maximum localization error in one direction is within ± 0.5 mm, which meets the application needs of robot glue positioning. The method can detect the offset of 6 degrees of freedom of the target workpiece at the same time, which has a wider application than the general 2D visual localization method. It can also be used for the localization of parts in other scenes.

Coherent imaging with multi-beam laser is considered as a key technique in ground based imaging. In the paper, the composition of multi-beam laser coherent imaging system is demonstrated in detail, the constraints between subsystem parameters are analyzed, and the array layout of multi-beam laser imaging transmitter is proposed. In the system, the laser aiming accuracy has an important impact on the imaging. The theoretical simulation indicates that the aiming error of the emitter array should be controlled within 5%. Finally, Design equivalent aperture as Φ1.5m experimental system and Imaging target successfully, verifying the correctness and feasibility of the system, and promoting the implementation of multi-beams coherent imaging technology.

We have theoretically investigated the physical realization of entangled coherent states using cavity quantum electrodynamics. Specifically, a protocol of the cyclic three-level atoms interacting with bimodal cavity QED is proposed. The results show that the entanglement degree of the entangled state can be maintained at a high level under certain conditions.

Diamond and diamond film have excellent performance in optics, electricity, mechanics, chemical stability, etc. Compared with bulk materials, diamond film has low cost and short preparation period, and has good laser damage characteristics, which can replace traditional films to achieve high performance. The laserinduced damage threshold, optical properties and morphology of diamond films are closely related to the growth conditions. In this paper, high-quality diamond films suitable for laser applications were grown on the surface of fused silica by microwave plasma chemical vapor deposition, and the effects of gas flow ratio and temperature on the optical properties of diamond films were studied. The effect of particle morphology on electric field and temperature field. Studies have shown that the growth quality of nanocrystalline diamond films is closely related to the flow ratio of methane/hydrogen and the growth temperature. When the flow ratio of methane/hydrogen is 3%, and the growth temperature is around 800℃, the surface roughness of the film is the lowest. The diamond film shows a morphology of (111) facets, the grain size is in the 20~200nm range, and the transmittance can reach up to 70%. The simulation of the laser electric field and temperature rise with different surface grain shapes shows that the grains of (111) facet can cause the electric field to increase by 2~4 times, and the temperature rise reaches 40~60℃.

Diamond films are transparent in a wide range of wavelengths (ultraviolet-far-infrared-terahertz bands are transmitted), and are used in optical windows, aircraft missile hoods, etc., where low-energy protons (keV magnitude) in space will create gaps, vacancies and other material radiation effects. In this paper, diamond films with different grain sizes were grown on the surface of fused silica by microwave plasma chemical vapor deposition, and the influence of proton irradiation on the surface morphology, optical transmittance and Raman spectrum of diamond films was studied. The ion distribution and vacancy distribution of diamond thin films under proton irradiation were calculated and analyzed by calculation (Monte Carlo method). When the flow ratio of methane/hydrogen was 1%, by adjusting the height of the sample stage, diamond nanocrystalline films with different growth temperatures were prepared on the surface of fused silica. After proton irradiation, the transmittance curve of the film has a slight red shift, and the transmittance decreases significantly in the wavelength range of 500-900nm, and the maximum transmittance decreases by 5-7%. After proton irradiation, the peak intensities of the Raman spectra become weaker, and the peak intensities of both the diamond phase and the non-diamond phase are weakened. Under the irradiation of protons with energy of 50keV, the main action depth of the diamond film is in the range of 2-5 microns, and the effect on the surface and deeper regions is not obvious, but gaps and vacancies are generated at a depth of several micrometers.