Insects/birds can use polarization information and geomagnetic to navigate. The bionic polarization navigation using the sky polarized light field as the information source has the advantages of good real-time and no cumulative error, which can improve the robustness of AHRS. The hardware and software integration of polarized light sensor, IMU, magnetometer are implemented to realize the integration and high performance of the system. And addressing the issue of polarization information being susceptible to interference based on Kalman filter and confidence estimation, the "polarized light/geomagnetic/inertial" fusion algorithm is designed. Finally, the performance of the system is tested. The RMSE of attitude and heading in static condition are 0.24°, 0.25° and 0.25°. Under dynamic condition, the attitude RMSE is 0.49° and 0.66°; under non-interference condition, the heading angle RMSE is 0.34°. Under light interference, the heading angle RMSE is 0.39°, which is 40% lower than before fusion; under magnetic interference, the RMSE is 0.38°, which is 86.1% lower than MTI AHRS. The results show that the system has high attitude accuracy and good robustness.

In the application scenario of the resonant cavity stably controlled of the passive mode-locked picosecond seed source, aiming at the problem of fine-tuning output voltage control, a piezoelectric ceramic stack driving circuit system based on field programmable gate array（FPGA）is designed. The pulse counting method is used for the design of pulse width modulation（PWM）circuit, and a capacitance-resistance-diode（CRD）high-frequency filter is employed to protect the circuit by detecting the frequency of the PWM control signal. The flyback boost principle is used to drive the 12 V voltage up. Within a range of 20% to 50% duty cycle of the control signal, the output voltage ranges from 29.1 V to 118.74 V with an output voltage ripple within 0.66%. The system allows for a step adjustment of duty cycle by 0.02%, enabling precise adjustment of output voltage, providing a foundation for further precise control of piezoelectric stack displacement and thus controlling the resonant cavity of picosecond seed source, while also having reference value for other industrial piezoelectric driving devices.

Focusing on the difficulty of 1 018 nm ytterbium-doped fiber laser, the suppression of amplified spontaneous emission（ASE）, a scheme is proposed to realize the suppression of ASE, which based on the master oscillator power amplifier, combined with the large-mode-field double-clad ytterbium-doped fiber. Fiber length and pumping parameters are optimized, narrow linewidth laser output of 50 W and light-to-light conversion efficiency of 43.6% are realized. The amplified spontaneous emission and self-oscillation are suppressed efficiently, while the side-mode suppression ratio is 40 dB. The output power instability is measured in the experiments with the value of RMS approximately equal to 0.50%, Vpp approximately equal to 2.02% in four hours. The fiber lasers can be used in second harmonic generation and optical parametric oscillation.

The 830 nm semiconductor laser（hereinafter referred to as the "power supply laser"）in electronic current transformers is an active optical device that supplies energy to remote modules. However, currently there are frequent cases of laser malfunctions, which seriously threaten the safe and stable operation of the ultra-high voltage power grid. This paper establishes a high current aging acceleration system and divides the samples into three aging test groups：2.1A, 2.3A, and 2.5A. The PIV curve scanning is conducted every 168 hours to study the degradation and attenuation characteristics of the powered laser during accelerated aging. After 2 100 hours of aging acceleration test, it is found that the attenuation rate of optical power became faster with the increase of acceleration current, and the slope efficiency changed only by about 3%, while the threshold current changed significantly by more than 10%. And it is proved that under controlled environmental temperature conditions, using the Eyring formula can better estimate the characteristic life of the powered laser, and it indicates that under a normal driving current of 0.7 A, the estimated characteristic life of the powered laser can reach 14.94 years. Furthermore, based on the analysis of the failed chips after accelerated aging, it is found that optical damage on the cavity surface is one of the main causes of their failure. Therefore, this study provides experimental data support and optimization direction guidance for predicting the health status of power supply lasers by studying the degradation law of lasers.

To achieve precise measurement of high-power laser parameters, this paper proposes a multi-parameter cross-verification method based on laser energy, near-field gray values of the light beam, and integral values of the optical waveform. The self-consistency of the test results of energy, near-field distribution, and temporal waveform is verified through intra-shot data comparison and multi-shot verification. Experimental results show that under unchanged attenuation conditions, the relative deviations of the three-parameter test ratios are all less than 2%. When the laser energy approaches the lower limit of the linear range of the measurement equipment, the relative deviation can be controlled within 3%. This method effectively solves the problem that data deviations are difficult to recheck in traditional independent testing and provides technical support for the accurate measurement of high-power laser device parameters.

The aperture in a spatial-carrier digital speckle pattern interferometry（SC-DSPI）system is a critical component determining its measurement performance. However, the specific impact of the aperture’s axial position remains underexplored. This study combines optical Fourier transform theory and experimental validation to analyze the influence of aperture axial displacement on spatial spectra and phase maps. Results indicate that altering the aperture position leads to spatial spectral loss, thereby degrading phase map quality. A trade-off exists between structural similarity（SSIM）and noise variance. Experimental optimization reveals that an intermediate position（65 mm）achieves a balanced improvement（SSIM 0.931, noise variance 3.82）, significantly enhancing phase map quality. This study provides important theoretical and practical guidance for optical path design and performance optimization in SC-DSPI systems.

Due to the advantages of fast response, multiple factors metering and easy implementation, the measurement method of light-screen array has been widely used in the measurement of external ballistic flight parameters of barrel rapid-fire weapons. Compared with the separated light-screen array, the integrated light-screen array measurement model has the advantages of simplified parameters, simple model and easy to use. In this paper, a seven-light curtain array measurement model is proposed, key light curtain structural parameters in the model are obtained, the model is established and simulation analysis is carried out. And a set of structural parameter optimization method is obtained by discussing the influence of each parameter on the measurement deviation of the flight speed and position of the projectile. Based on the optimized structural parameters, the error distribution of the projectile’s flight velocity and position coordinates is obtained in the 1 m×1 m rectangular target area. The model method presented in this paper can be used as the design basis of the optical curtain array measurement device, and can also provide guidance for improving the accuracy of the measurement of the projectile motion parameters of the linear propulsion mechanism.

In order to achieve portable and easy analysis of flame combustion spectra in industrial applications and improve the flexibility and applicability of actual on-site detection, a portable flame gas phase alkali metal monitoring system for on-site testing is developed based on the combustion spontaneous emission spectrum analysis method. Through this system, the radiation spectrum parameters emitted by the combustion flame of three different Zhundong coals are studied in the combustion test in the liquid slag discharge furnace, and the gas phase alkali metal concentration is obtained after processing and analyzing the parameters. The results show that under the same temperature conditions, for the same wavelength, different types of pulverized coal combustion flame emissivity are different. For the same pulverized coal, the flame temperature affects the flame emissivity and the band thermal radiation energy, and promotes the release of gas-phase alkali metal sodium. At the same time, flame self-emission spectrometry can analyze other alkali metal elements in the combustion flame.

Disorders of consciousness（DOC）, commonly known as “vegetative state”, is one of the most difficult medical problems in the world. At present, there is no exact and effective means for the detection of consciousness in clinical environment. Functional near-infrared spectroscopy（fNIRS）is a promising non-invasive optical neuroimaging technology with significant potential in the field of disorders of consciousness. In this study, the residual consciousness of patients with DOC is detected using mental arithmetic tasks based on fNIRS. The results show that the healthy control group exhibited significant task-evoked hemodynamic responses in the prefrontal cortex. Reliable hemodynamic responses similar to those of healthy control group can also be detected in some of the patients with DOC. At the group level, significant differences in hemodynamic responses are observed between patients with the unresponsiveness wakefulness syndrome（UWS）and minimally conscious state（MCS）during mental arithmetic tasks. The results show that fNIRS combined with mental arithmetic task may serve as a viable neuroimaging approach for detecting residual consciousness in patients with DOC.

This article focuses on the shortcomings of commonly used reducing methods that cannot effectively separate noise when noise and signal boundaries reach a certain balance. A Raman spectroscopy digital reduction technology based on phase-locked technology is studied, which includes modulating the output light intensity of the laser with a sine wave, using an optical system to read and separate the Raman signal, and then using phase-locked filtering technology to achieve the purpose of reducing. The research results indicate that compared with traditional Raman spectroscopy reducing techniques, this technique adopts a separation before detection approach, which avoids the balance between noise and signal boundaries that traditional reducing algorithms cannot balance at the root, and can effectively improve the signal-to-noise ratio of sample Raman signals. By reducing the spectrum of acetaminophen, it can be observed that the noise signal in the sample spectrum is significantly eliminated, and the signal-to-noise ratio is increased by 10 times. This method is universal and particularly helpful for detecting weak Raman signals.

When confocal microscopy is combined with resonance Raman spectroscopy, the focusing accuracy of the system decreases due to the movement of the convergence plane of the beam caused by the change of the working wavelength. In this paper, a differential confocal microscopy focusing technique with variable working wavelength is proposed, and the basic theory of confocal technique based on the wavelength-convergence plane position relationship is established, which can provide a precise theoretical basis for the determination of the focusing accuracy of the confocal resonance Raman technique, and the axial resolving power is 6 nm, which greatly improves the system accuracy. It is experimentally verified that this technique can eliminate the influence of the change of working wavelength on the focusing accuracy of the system, which lays the foundation for detecting the morphology imaging of micro-regions, and provides theoretical support and help for the development of the confocal resonance Raman technique.

Tilting fiber bragg grating（TFBG）is a unique type of fiber bragg grating（FBG）. Its unique ness lies in a certain degree of inclination angle between the grating surface inscribed inside the fiber and the axial direction of the fiber. This design makes the transmission mode of optical fiber not limited to the core mode, which leads to the coupling of various modes becomes more complex. This paper describes the spectral characteristics of four small-angle TFBG of 1°, 3°, 5° and 7°. And strain sensing tests are carried out on them by cantilever beam of equal intensity. The resonance peaks drift of the cladding mode and the core mode are demodulated respectively. The test results show that the drift of cladding mode and core mode drift of small-angle TFBG with the strain is linear. The sensitivities of the cladding modes are 0.85 pm/, 0.67 pm/, 1.17 pm/, 0.85 pm/. And the sensitivities of the core modes are 1.05 pm/, 1.04 pm/, 1.29 pm/, 0.86 pm/. It has certain application prospects in the field of new sensing test such as strain.

Spaceborne laser altimeters are active remote sensing instruments, currently offering the highest accuracy in spaceborne elevation measurements. The latest generation of single-photon laser altimeters provides extremely high spatial resolution and precision, delivering detailed surface elevation profiles and representing a key direction in future development. However, the increased along-track measurement density and the use of highly sensitive single-photon detectors result in a data volume several orders of magnitude higher than that of traditional systems, imposing significant burdens on satellite data transmission and processing. To address this issue, a footprint prediction method based on position iteration is proposed, followed by the development of a dynamic range gate prediction algorithm to enable more effective data filtering. Validation using ICESat-2, the only currently operational single-photon laser altimetry satellite, shows that in a test area with a maximum terrain relief of 606 m, the predicted range gate（without margin）fullly covers of ground elevation with dynamic widths ranging from 468 m to 704 m. The algorithm’s prediction time remains under 0.8 s. These results demonstrate the algorithm’s strong adaptability and computational efficiency, providing technical support for future Chinese satellite missions using single-photon laser altimetry.

As a common way of generating structured light, projectors are widely used. When monocular structured light is used to measure color three-dimensional objects, the reflection intensity of projective fringes at different positions will be different due to the rich color information of the object surface, which will result in low SNR error and saturation error. In addition, due to the projector itself and equipment lens distortion and other factors, it may also lead to measurement errors. In order to solve the above problems, the response curve of the system is fitted first, and then the response function of the projector is separated from the response function of the camera. By calculating the reflectance of each point, the optimal projection fringe adapted to the reflectance of the measured object is generated, and the error caused by the non-uniform reflectance of the measured object is reduced. Finally, based on the optimal projection, the error of each period is estimated according to the period value of the projection fringe, and the error is compensated in the measurement process. This measurement method can effectively reduce the impact of the surface color of the object and the equipment itself on the measurement results. The results of three-dimensional reconstruction of color planar objects show that the deviation of phase calculation is between ±0.04（rad）, and the accuracy is about 70% higher than that of the traditional method. The precision of phase calculation of color three-dimensional objects is also about 40% higher than that of traditional methods.

The success of space rendezvous missions hinges on the accuracy of target detection. To address the challenges of target detection in distant non-coplanar rendezvous, including similarities between space targets and stars, minimal distinctive features, random imaging trajectories, and slow stellar motion, a space target detection algorithm based on star correlation and trajectory matching is proposed. Initially, multi-frame star map images undergo preprocessing, including noise reduction, threshold segmentation, centroid localization, and image registration. Subsequently, a multi-frame star association is performed using the proposed correlation function and association rules, filtering out stray noise points while extracting the inter-frame motion trajectories of star points. Finally, trajectory matching is conducted using three indicators：target size, velocity, and direction, to detect the space target. Simulation results demonstrate that the algorithm meets the detection requirements of non-coplanar rendezvous processes In the presence of a certain degree of frame mismatch, the spatial target detection rate can reach 99.8%, and the false alarm rate is 0.04%.

With the continuous progress of technology and the rapid development of industrialization, automated production lines have become an important component of modern industry, and industrial lenses need to detect product appearance defects, size, position, and text information on high-speed assembly lines. In response to the problems of slow focusing speed and complex structure of traditional industrial lenses, this paper designs a long focus adjustable optical system with a large target area based on ZEMAX. The method uses a liquid lens to achieve millisecond level fast focusing effect and a more compact optical structure. The optical system has a focal length of 50 mm, a total length of 137.869 mm, a target area of 1.1 inches, a working distance of 300 mm to infinity, full field resolution is 145 lp/mm>0.3, distortion<1%, and can perform high-definition imaging and meet the basic requirements of part processing technology.

A bionic polarization detector based on multi-layer structure is proposed in this paper, and the polarization sensitive metasurface bionic structure is designed for the main role. The structure can simulate the compound eye of insects and construct a three-layer polarization sensing structure by combining transparent photosensitive material and metal grating metasurface structure. By designing and optimizing the metasurface bionic layer for polarization detection at 532 nm wavelength, it is determined that the metasurface bionic layer with a metal thickness of 10 nm can obtain the best effect, that is, the extinction ratio is 8 dB, and its effect is verified by simulation analysis. The structure can simultaneously measure the multi-angle component information of a single incident light in space. Through multi-point combination detection, the structure can also realize graphical detection. The novel bionic stereo stacked polarization detector designed in this paper provides a feasible idea for more advanced polarization detection in the future, and can achieve better polarization detection.

The synthesis of nanostructured zinc oxide（ZnO）and its applications in nanogenerators are investigated. High-performance ZnO nanorods are successfully synthesized using magnetron sputtering and hydrothermal methods. The morphology of the nanorods, grown under various conditions, is analyzed and compared using scanning electron microscopy（SEM）and other characterization techniques. A nanogenerator is fabricated by spin-coating Poly（methyl methacrylate）（PMMA）onto the nanorods. The influence of the generator’s dimensions and external excitation on its performance is studied using a controlled variable approach. The results indicate that the nanorods, grown via the hydrothermal method at 95 ℃, a concentration of 30 mmoL/L, and a duration of 4 hours, exhibited optimal morphology. The nanogenerator demonstrated the enhanced output performance with increased size and stronger external excitation. Testing results revealed that the generator could charge a capacitor to 0.5 V after 60 seconds of turntable impact and could illuminate up to four LED bulbs after charging for 240 seconds. This research confirms the power generation capabilities of the ZnO nanogenerator, highlighting its potential as a self-powered energy source for small-scale devices.

To solve the coating process problems of large-diameter infrared components with DLC film layers and meet the technical requirements of long-focal-length, large-field-of-view optical systems, the radio frequency plasma chemical vapor deposition（RF-PECVD）coating method is adopted. Based on the capacitive coupling plasma standing wave effect and the skin effect mechanism, diamond-like carbon（DLC）film is deposited on the substrate of large-diameter infrared components. By optimizing and improving the uniformity of the plasma electric field, the stress of the film layer is effectively reduced and the reliability and uniformity of the film thickness are improved. According to the environmental test requirements of optical thin film components, high temperature, low temperature, and humidity and heat tests are conducted. After the test, no peeling, folding, or falling off of the film layer is observed. The results show that the large-diameter infrared diamond-like carbon film has good temperature shock and corrosion resistance properties, which meet the normal requirements of optical coating.