Journals >Opto-Electronic Engineering
Contents
2010
Volume: 37 Issue 4
28 Article(s)
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Research Article
Guidance Tracking Method of a New Automatic Laser Theodolite System
ZHANG Zi-li, ZHU Ji-gui, ZHOU Hu, GENG Na, and YE Sheng-hua
To solve the low precision and efficiency problem of traditional theodolite system due to manual target alignment, a new automatic laser theodolite system was presented which could realize automatic measurement by using a guidance system consisting of a digital camera mounted on servo stages rotating in horizontal and To solve the low precision and efficiency problem of traditional theodolite system due to manual target alignment, a new automatic laser theodolite system was presented which could realize automatic measurement by using a guidance system consisting of a digital camera mounted on servo stages rotating in horizontal and vertical directions. The TM5100A motorized theodolites were used to point at the view field of the camera to realize the guidance process, and then the recognition and measurement process was completed by using the recognition and measurement method. The former method was emphatically introduced and analyzed. The simulation and test result shows that the guidance methodology is feasible and efficient to realize accurate guidance of the theodolites..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 1 (2010)
A Novel Method for Moving Object Detection Based on Markov Random Field
REN Ming-yi, LI Xiao-feng, and LI Zai-ming
A novel method for detecting moving objects from video sequences is proposed based on Markov random field. In order to overcome the drawback of subjective fixed threshold of traditional temporal segmentation, the difference image is modeled by Markov random field. A novel method for deciding the model size and initial A novel method for detecting moving objects from video sequences is proposed based on Markov random field. In order to overcome the drawback of subjective fixed threshold of traditional temporal segmentation, the difference image is modeled by Markov random field. A novel method for deciding the model size and initial parameters of MRF, and a new iteration method for greatly accelerating the convergence are proposed. Then, the Expectation-Maximization (EM) algorithm is carried out to obtain the Gaussian parameters and temporal moving area is detected. The temporal segmentation is then amended by morphological operations. Considering the lack of traditional spatial segmentation algorithm of watershed, an improved watershed algorithm in accord with the human vision characteristics, which can restrain over-segmentation effectively, is proposed. The temporal and spatial information fusion is fulfilled by ratio operation, and the moving objects are obtained. The emulation experiments demonstrate the validity of the proposed algorithm..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 8 (2010)
An Efficient Detection Algorithm for Decreasing False Alarm Rate of Infrared Surveillance System
LI Peng, and CHEN Qian
Because of the influence of surface objects, such as clouds and birds, etc., the false alarm rate of infrared surveillance system is easy to be higher than the imagined. In order to decrease its false alarm rate effectively, a detection algorithm is researched by analyzing the changes of object’s angle coordinate. An oBecause of the influence of surface objects, such as clouds and birds, etc., the false alarm rate of infrared surveillance system is easy to be higher than the imagined. In order to decrease its false alarm rate effectively, a detection algorithm is researched by analyzing the changes of object’s angle coordinate. An optimal method is used which combines the interior point penalty function method and the steepest descent algorithm, so as to judge the routes of all the correlative objects and to differentiate the real object from all the interferences. At last, some experiments were carried out to prove that the proposed method can improve the anti-interference capability and decrease the false alarm rate in real time..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 15 (2010)
A Defocus Model of Star Image Based on the Observation of Drift-scanning Mode
CHEN Dong, LIN Jian-lin, and MA De-bao
The technique of drift-scanning is efficient in working, but the observation of drift-scanning mode would defocus the imaging energy inevitably. The models for analyzing the value of the defocus quantificationally was built, which provides the theoretical reference for the evaluation and improvement on the image qualitThe technique of drift-scanning is efficient in working, but the observation of drift-scanning mode would defocus the imaging energy inevitably. The models for analyzing the value of the defocus quantificationally was built, which provides the theoretical reference for the evaluation and improvement on the image quality of spatial targets. Firstly, the principles of both drift-scanning and spatial projection imaging were analyzed. Then, the relevant spread models of targets’ energy were set up, which were used to give a quantificational analysis individually on the defocus of non-synchronization caused by the charge’s mismatch with star image in the moving velocity, and the defocus of track-projection brought by the spatial targets’ curve movement. Finally, a simulated experiment was made to validate the feasibility of the relevant defocus models, whose applicability were also discussed..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 20 (2010)
Study of the Normal Gastric Mucosa, Intestinal Metaplasia and Adenocarcinoma Genomic DNA by Using Raman Spectroscopy
DAI Jian-hua, RAO Yun-jiang, RAN Zeng-ling, ZHANG Yan-liang, XUE Shi-xiang, and PENG Gui-yong
A method for systematically investigating the DNA space structure of different issue during the occurring process of adenocarcinoma is proposed, by incorporating issue DNA extraction technology and Raman spectroscopy technology. In experiment, DNA solutions of normal gastric mucosa, intestinal metaplasia and adenocarciA method for systematically investigating the DNA space structure of different issue during the occurring process of adenocarcinoma is proposed, by incorporating issue DNA extraction technology and Raman spectroscopy technology. In experiment, DNA solutions of normal gastric mucosa, intestinal metaplasia and adenocarcinoma are firstly extracted, and then their Raman spectra are measured, respectively. According to the Raman spectra, genomic DNA is analyzed in detail. The experimental results show that: DNA of normal gastric mucosa has stable phosphate backbone; Since the peak intensity at 1 090 cm-1 is lower than that at 1 050 cm-1, phosphate backbone in DNA of intestinal metaplasia becomes unstable, while the rest spectra peaks are similar to those in normal gastric mucosa; In terms of adenocarcinoma DNA, double peaks at 1 090 cm-1 whose intensity are higher than 1 050 cm-1, are observed, which indicates that DNA chain is broken and re-forms a double stabilized phosphate backbones. In addition, peaks at 950 cm-1, 1 010 cm-1, 1 100~1 600 cm-1 also exhibit obvious difference compared with normal gastric mucosa, which shows that deoxyribose and bases are changed due to broken of DNA. All these results indicate that the DNA variation process during the occurring process of adenocarcinoma may be: the stable DNA phosphate backbone in normal gastric mucosa change into unstable DNA phosphate backbone in intestinal metaplasia issue under affecting of pathogenic factors, and finally, DNA phosphate backbone is broken and re-forms a double stabilized phosphate backbones, which causes the occurring of adenocarcinoma..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 25 (2010)
Simulation Studies of the Influence of Gas Refractive Index Change Around the Aircraft on Laser Measuring
ZHAO Yu-hua, YUAN Feng, DING Zhen-liang, and LI Jing
In laser measurement for aircraft position parameters, when laser-beam passes through gas field produced by aircraft, the beam curves due to different refractive index in gas fluid field, which influences measurement result. This paper analyses the distribution regularity of refraction index in gas fluid field based onIn laser measurement for aircraft position parameters, when laser-beam passes through gas field produced by aircraft, the beam curves due to different refractive index in gas fluid field, which influences measurement result. This paper analyses the distribution regularity of refraction index in gas fluid field based on aerodynamics theory, establishes the simplified mathematical model, presents the factors causing the measurement errors, calculates the errors of laser beam curve and corrects the measurement result. This method improves the accuracy of measurement system and benefits the system design. Experimental results show that the method can calculate the errors of measurement results effectively..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 30 (2010)
Application of Frequency-domain Interferometry in Pump-probe Experiments
WENG Ji-dong, LIU Cang-li, LI Jian-feng, CAI Ling-cang, TAN Hua, ZHONG Jie, WANG Xiang, and MA Yun
On the basis of careful investigation for the frequency-domain interference, a new technology named pulse frequency-domain interferometry is illustrated. By means of the new technology, the pump pulse and probe pulse can arrive at the measured target synchronously in the pump-probe experiments. The time resolution of fOn the basis of careful investigation for the frequency-domain interference, a new technology named pulse frequency-domain interferometry is illustrated. By means of the new technology, the pump pulse and probe pulse can arrive at the measured target synchronously in the pump-probe experiments. The time resolution of frequency-domain interferometry is more than the pulse period. The work principle and system structure are illustrated in detail. After simulating the output signal of frequency-domain interferometry in theory, it comes to a conclusion that the pump pulse and probe pulse have arrived at measured target synchronously when only one output stripe appears in frequency-domain interferometry. Further dynamic experiments draw the same result as is shown in theoretic simulation..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 34 (2010)
Application of CCD in Measuring Steam Moisture and Droplet Size
HUANG Zhu-qing, CAO Xiao-ling, YANG Ji-ming, WU Wei, XIAHOU Guo-wei, HU Feng, and ZHOU Zhen
In order to accurately measure the steam moisture and droplet size, a new method is proposed to measure the light scattering in steam turbine, and by optimal numerical fitting, we can get the value of steam moisture distribution and droplet size. According to the characteristic of CCD imaging and light scattering theorIn order to accurately measure the steam moisture and droplet size, a new method is proposed to measure the light scattering in steam turbine, and by optimal numerical fitting, we can get the value of steam moisture distribution and droplet size. According to the characteristic of CCD imaging and light scattering theory, the experimental platform including the measurement system and simulation system of steam turbine is set up. The laser with the wavelength of 532nm is adopted to irradiate the moisture gas, and the light scattering distribution by the scale of 2.6°～6.6° is measured by CCD, so the steam moisture distribution(0.7%~1.2%) and average droplet size(1.4 ~1.6μm) can be calculated by curve fitting. The experimental results indicate that this method can be used to measure steam moisture and droplet size, and the large scale can be achieved by using CCD. Furthermore, the experimental results also vividly reflect the varying rule of steam moisture and droplet size, so the feasibility of application of CCD technology in measure of steam moisture is supported strongly..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 39 (2010)
Measure Method with Solid Cavity Thickness of Optical Comb Filter
DENG Chun-lin, CAI Wei, ZHANG Zhi-li, LU Jin-jun, and QU Zhan-guo
According to the theory of Fabry-Perot (F-P) interference, the measurement of no plated membrane light filter is implemented by choosing flat glass (SiO2) as interferometric cavity of the measurement system, and adopting the method for measuring the extremum between two nearby interfered lights. It is the most importanAccording to the theory of Fabry-Perot (F-P) interference, the measurement of no plated membrane light filter is implemented by choosing flat glass (SiO2) as interferometric cavity of the measurement system, and adopting the method for measuring the extremum between two nearby interfered lights. It is the most important part of the new Ultra-narrow Bandwidth filter. Based on solid-cavity thickness of supper narrow band optical comb filters, the precision of height measurement comes true. Experimental results indicate that the accuracy of the optical measurement system with simple configuration and low-cost reaches subnanometer level, as well as strong anti-jamming and stabilization. The system can be adapted to measure transparent medium such as plat-glass, filters, optical coating as well as no plated membrane filters..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 44 (2010)
Feasibility of Real-time Monitoring for Large-scale Collimator
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
To monitor the imaging quality of the large-scale collimator, a new method for monitoring the large-scale collimator in real time is proposed, and feasibility of the method is verified. Based on the principle of autocollimating detection, the method uses small plane mirrors to monitor the imaging quality of collimator To monitor the imaging quality of the large-scale collimator, a new method for monitoring the large-scale collimator in real time is proposed, and feasibility of the method is verified. Based on the principle of autocollimating detection, the method uses small plane mirrors to monitor the imaging quality of collimator in real time. The error of the rotating angle of small plane mirror within one focal depth is calculated, and the method demonstrates that the error of the rotating angle of small plane mirror can be controlled within the 0.2″ in one focal depth by using an autocollimator whose accuracy is 0.02″. It plays a role in real time monitoring to the large-scale collimator. The large-scale collimator is widely used for the space remote sensing equipment, and the method for monitoring the collimator will act an active role in the engineering..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 48 (2010)
FPGA Delay-line Interpolation Method for Laser Range Finding
FENG Zhi-hui, LIU En-hai, and YUE Yong-jian
In order to improve the system density of integration and maintain the precision simultaneously, Field Programmable Gate Array (FPGA) delay-line interpolator is introduced to realize pulsed laser ranging with high time resolution and precision. The method is based on clock circle dived principle. The time errors in dirIn order to improve the system density of integration and maintain the precision simultaneously, Field Programmable Gate Array (FPGA) delay-line interpolator is introduced to realize pulsed laser ranging with high time resolution and precision. The method is based on clock circle dived principle. The time errors in direct digital counting method are converted to digital flash-code by latching the output of FPGA delay cells. Then a latch method for latching the delay cell signals was proposed based on the high frequency clock (400 MHz). The corresponding time-to-digital interpolation converter and delay cell time measurement were also designed. The measurement shows that single-shot resolution can be improved to 80ps, and average resolution can reach 40ps (mm level). Applied in pulsed laser range finder, the distance results are given and the error of FPGA interpolation method is analyzed in theory. Finally, the precision of ±10 centimeter level is achieved..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 53 (2010)
Inverse Fringe Projection and Its Application in the Digital Globe
TANG Ting-yong, and SU Xian-yu
A digital globe based on the inverse fringe projection is presented. In the digital globe, the display screen is a spherical surface of the diffuse reflection screen and through the method of projection, digital globe rotating display in any direction can be achieved. First of all, sinusoidal fringes are projected to tA digital globe based on the inverse fringe projection is presented. In the digital globe, the display screen is a spherical surface of the diffuse reflection screen and through the method of projection, digital globe rotating display in any direction can be achieved. First of all, sinusoidal fringes are projected to the spherical screen. Then, from the direction of observing globe, the digital CCD camera is used to obtain deformation fringe images. Through the phase-shifting algorithm, we can establish the transmission geometry between the projector and camera pixels. The inverse projected images for projector can be generated according to the expected images, which come from the 3D Earth graphics information database. 3D information extraction model of the Earth is established to quickly acquire Earth's graphics information in any observation point. In the experiment, the calculated inverse map is projected onto a spherical surface with the diffuse reflection screen,whose the radius is 25 cm. The experimental results are quite satisfactory..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 60 (2010)
Automatic Mura Detection for TFT-LCD Based on Wavelet Multi-scale
GUAN Xin, and MOU Tong-sheng
An automatic inspection method was proposed based on polynomial surface fitting and wavelet multi-scale. The influence of non-uniform background is successfully removed and Mura area was gotten. Related international organizations have drafted a standard on quantification Mura considering on area and contrast. ParameteAn automatic inspection method was proposed based on polynomial surface fitting and wavelet multi-scale. The influence of non-uniform background is successfully removed and Mura area was gotten. Related international organizations have drafted a standard on quantification Mura considering on area and contrast. Parameter of location was proposed according to the visual space of human eyes. We carried out some experiments on human factors, and got the relationship between the location of the Mura area and threshold of visual contrast. At last, 13 real TFT-LCD panel samples were evaluated with the proposed method, and the result is consistent with human intuition..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 66 (2010)
Circle Detection Algorithm Based on Conformal Geometric Algebra and Radon Transform
LI Mao-kuan, and GUAN Jian
To meet the need of object detection problem in images, a circle detection algorithm based on conformal geometric algebra and Radon transform is proposed. From a new point of view, the probability and simplicity for using the concept of conformal geometric algebra to solve circle detection problem is discussed in detaiTo meet the need of object detection problem in images, a circle detection algorithm based on conformal geometric algebra and Radon transform is proposed. From a new point of view, the probability and simplicity for using the concept of conformal geometric algebra to solve circle detection problem is discussed in detail. Circles in Euclidean space can be represented as vectors by the conformal geometric algebra theory, a circle may be implemented as a plane in conformal space, and the plane in conformal space can be detected by 3D radon transform. This algorithm can detect circles in images effectively. The experimental results show that the proposed algorithm is compact and explicit, multi-circles in images can be detected by using this algorithm, and the integration of algorithm has an important significance in the improvement of efficiency..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 72 (2010)
Design of Catadioptric Variable Focus Beam Expanding Optical System
ZHAO Yang, and GONG Yan
In order to obtain different diameters of laser beam by using one optical system, a catadiopric beam expander zoom optical system was designed. The beam expanding ratio was changed from 55 to 155 continuously, which was greater than before, and could expand the application areas. The system was composed of two main parIn order to obtain different diameters of laser beam by using one optical system, a catadiopric beam expander zoom optical system was designed. The beam expanding ratio was changed from 55 to 155 continuously, which was greater than before, and could expand the application areas. The system was composed of two main parts: one afocal zoom system was located in the front could achieve continuous laser beam expanding. Only four sphere lenses were used to design the zoom system. In order to reduce the size of total system, a “Positive-Negative-Positive” form was introduced. The material of variable part of zoom system was analyzed because the beam diameter was so small that the distortion was appeared for the temperature changing by the laser irradiation. The other secondary catadioptric system was used to achieve high ratio beam expanding. A sphere mirror was used to replace an off-axial parabolic mirror, and a meniscus lens was introduced to compensate aberrations. The lens in the secondary system was so important to the performance that it was analyzed, and then the thickness and material of the lens were chosen. The model was built up in CODEV. By optimizing aberrations, the performance of the system reaches diffraction limitation after adding perfect lens. Finally, the software light tools were used to analyze the collimation and the result matches the theoretical design..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 77 (2010)
Slab Compensated Auto-collimation Method to Test Primary Mirror of TMC System
ZHONG Xing, LIU Chun-yu, and JIN Guang
For testing the concave ellipsoidal mirror of Three Mirror Cassegrain (TMC) optical system, a slab compensated auto-collimation method is suggested. This method can avoid the problem that the performance of null compensator is hard to be evaluated, and the development of null compensator cost too much. Taking advantageFor testing the concave ellipsoidal mirror of Three Mirror Cassegrain (TMC) optical system, a slab compensated auto-collimation method is suggested. This method can avoid the problem that the performance of null compensator is hard to be evaluated, and the development of null compensator cost too much. Taking advantage of the shape of TMC system’s primary mirror near to parabolic, slab compensated auto-collimation method is analyzed to test it. Expression of spherical aberration in testing optical system is deduced by conic aspheric normal character, and the parameters of compensated slab are given by solving minimal residual spherical aberration. For test of some actual Φ500 mm mirror which has 1 589 mm vertex radius and -0.983 conic coefficient, a slab compensator with only size Φ34.2 mm× 9.126 5 mm is designed. The wavefront aberration of test optics compensated by slab is only 0.003λ, matching the demand of precise test. The test, manufacture and use of the slab are also considered. The slab compensated auto-collimation method is obviously low-cost, and it is easy to evaluate the performance of the slab..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 83 (2010)
Composite Photon Sieve and Its Application in Large Aperture Imaging
PAN Yi-ming, XIE Chang-qing, and JIA Jia
Large aperture photon sieve for imaging often has low efficiency and huge size of GDSII file, which makes their implementation difficult in practice. The composite photon sieve which compounds the zone plate to the R/3-2R/3 part of the conventional photon sieve is presented. The simulation result shows that the elementLarge aperture photon sieve for imaging often has low efficiency and huge size of GDSII file, which makes their implementation difficult in practice. The composite photon sieve which compounds the zone plate to the R/3-2R/3 part of the conventional photon sieve is presented. The simulation result shows that the element can reach higher diffraction efficiency and significantly reduce the GDSII file size. In the experiment, a conventional photon sieve and a composite photon sieve with the same feature size are designed. The imaging result shows that the composite photon sieve can reduce the GDSII file size by 38% and has a better contrast than the conventional photon sieve. Therefore, the composite photon sieve is a good element applied in large aperture imaging in soft X-rays..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 88 (2010)
A FBG Sensor System for Dynamic Strain Measurement Based on F-P Etalon and Music Algorithm
LU Jing, RAO Yun-jiang, and RAN Zeng-ling
A sensing system with a high optical Signal Noise Ratio (SNR) of >60 dB, which is based on a tunable fiber ring laser configuration, is proposed for the dynamic strain measurement. An F-P etalon serving as edge filter is used to detect the wavelength shift of the Fiber Bragg Grating (FBG) sensor. Such a demodulationA sensing system with a high optical Signal Noise Ratio (SNR) of >60 dB, which is based on a tunable fiber ring laser configuration, is proposed for the dynamic strain measurement. An F-P etalon serving as edge filter is used to detect the wavelength shift of the Fiber Bragg Grating (FBG) sensor. Such a demodulation device has the advantage of stability. In addition, in order to improve the resolution for dynamic strain measurement, a modern spectral analyzing algorithm called Music modern spectrum estimation is adopted. The experimental results show that a dynamic strain resolution of 0.1 με/Hz1/2 at 700 Hz is obtained, which is 10 times better in terms of strain resolution compared with conventional FFT method..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 93 (2010)
Performance of the Double-pass Discrete Raman Amplifier
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
The gain of the new type Double-pass Discrete Fiber Raman Amplifier (D-DFRA) is calculated under the backward pumping scheme. The experimental measurement for gain performance, noise figure and Stimulated Brillouin Scattering (SBS) are conducted in the case of double-pass pumping. The experiment results are fairly consThe gain of the new type Double-pass Discrete Fiber Raman Amplifier (D-DFRA) is calculated under the backward pumping scheme. The experimental measurement for gain performance, noise figure and Stimulated Brillouin Scattering (SBS) are conducted in the case of double-pass pumping. The experiment results are fairly consistent with the calculated results. This study demonstrates that the gain and pump efficiency can be improved significantly by using the double-pass configuration, the pump light reflector with the pump power keeping unchanged and the noise performance keeping fairly good. The upper limit of the gain is determined by the threshold of the SBS of the system. The maximum gain can be raised in the case of double-pass pumping..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 97 (2010)
Optical Coupling between Expand Core Fiber and Wide Grating Coupler
LE Zi-chun, HU Jin-hua, and ZHANG Ming
In order to study the effective coupling between optical fiber and wide waveguide grating (≥30 microns), an expand core fiber is designed for a given wide waveguide grating of 30 microns based on the theory of coupling Gaussian beam into waveguide grating, by using the method of matrix optics technologies and Gaussian In order to study the effective coupling between optical fiber and wide waveguide grating (≥30 microns), an expand core fiber is designed for a given wide waveguide grating of 30 microns based on the theory of coupling Gaussian beam into waveguide grating, by using the method of matrix optics technologies and Gaussian beam theories. After the coupling loss is analyzed, the model of coupling expand core fiber with waveguide grating is built. By optimizing the structure of the fiber, 10.8 microns waist radius of output beam is obtained theoretically. At last the structure tolerance of the expand core fiber is studied. And then the optical coupling efficiency imposed by the position of Gaussian beam on the grating is discussed by comparing the Gaussian beam output from expand core fiber, single mode fiber and free space Gaussian beam with waist radius of 16 microns. The results are that the position tolerance of the expand core fiber is more than that of single mode fiber and almost the same as that of Gaussian beam with waist radius of 16 microns..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 102 (2010)
Convergence Analysis of IC-PSO Algorithm and Its Application Research
ZHU Qi-guang, and WANG Hong-rui
Considering that the standard (Particle Swarm Optimization) PSO algorithm has low iteration efficiency during later period and may trap to local optimum, Immune Clone (IC) principle is introduced into the PSO algorithm. The antibodies can be regarded as the particles. According to the degree of affinity, the clone seleConsidering that the standard (Particle Swarm Optimization) PSO algorithm has low iteration efficiency during later period and may trap to local optimum, Immune Clone (IC) principle is introduced into the PSO algorithm. The antibodies can be regarded as the particles. According to the degree of affinity, the clone selection, clone suppression, and high-frequency mutation are performed, which can enhance the diversity of particle swarm and the capability of global searching. The optimal compensation experiment is performed in the 40 Gb/s transmission system, in which the compensation time required was about 71 ms. The opening of signal eye diagram has been improved obviously after compensation. The experimental results demonstrate the effectiveness of the algorithm proposed..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 108 (2010)
A Fuzzy Feature Integrating to Geodesic Active Contour Model for Image Segmentation
SHI Cheng-xian, MA Zheng-hua, and WANG Hong-yuan
It has been integrated into geodesic active contour model for the image segmentation that the fuzzy feature vector governs the normal force of curve. The modified model may contain more information of image segmentation. When fuzzy feature represents region information, the modified model has performance of region featIt has been integrated into geodesic active contour model for the image segmentation that the fuzzy feature vector governs the normal force of curve. The modified model may contain more information of image segmentation. When fuzzy feature represents region information, the modified model has performance of region feature uniform in all the same edges indication for segmentation image. This method has a large capture range of interested region, improves performance of segmenting concave and convex objects and provides an accurate segmentation to weak edges and noise image. Experimental results of applying new scheme to real images demonstrate its segmentation power..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 113 (2010)
Moving Target Detection Based on Improved Gaussian Mixture Model
CUI Wen-pin, and SHEN Ji-zhong
The traditional Gaussian Mixture Model (GMM) is built based on every single pixel in RGB color space, which leads to inaccurate detection results, trailing smear and inanition inside the moving objects. The improved GMM is built in HSV color space, which is fit for human visual system. Single pixel is taken place by a The traditional Gaussian Mixture Model (GMM) is built based on every single pixel in RGB color space, which leads to inaccurate detection results, trailing smear and inanition inside the moving objects. The improved GMM is built in HSV color space, which is fit for human visual system. Single pixel is taken place by a vector which is composed of central pixel itself and its neighbor pixels in order to improve the performance of the model. The connected area is extracted through color segmentation method in order to make full use of the color information. Finally, the shadow area is restrained by Phong’s object lighting model. According to the results of experiments, the improved algorithm can detect moving objects much more precisely. Compared with the traditional GMM, it is robust to lighting changes and shadow..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 118 (2010)
Color Edge Detection Based on Mathematical Morphology in HSI Space
GAO Li, and LING Xiao-ming
It is difficult to effectively distinguish the similarity between colors in RGB color space, so color image processing is implemented in HSI space which reflects the features of human vision. An adaptive algorithm of color image edge detection based on multiple structure and multi-scale elements in HSI space is proposeIt is difficult to effectively distinguish the similarity between colors in RGB color space, so color image processing is implemented in HSI space which reflects the features of human vision. An adaptive algorithm of color image edge detection based on multiple structure and multi-scale elements in HSI space is proposed. Firstly, morphological edge detection is executed by using different structure and different scale elements to hue, saturation and intensity. Then, according to the weight derived from information entropy, the color edge information is obtained by combining component’s edge information. The experimental results show that proposed algorithm can make full use of the hue, saturation and intensity information to effectively eliminate the noise and adaptively extract the complete edge information..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 125 (2010)
Video Object Segmentation Algorithm Based on Marker Multi-measure Watershed
CHENG Shu-hong, ZHANG Dian-fan, HU Chun-haia, and CAI Jing
Arming at the video object-extracted issue, video object segmentation algorithm is proposed based on marker multi-measure watershed. First, based on the frame difference detection, the initial motion object binary model is obtained by improved minimum Tsallis-cross entropy and morphologic managed. Second, markers of foArming at the video object-extracted issue, video object segmentation algorithm is proposed based on marker multi-measure watershed. First, based on the frame difference detection, the initial motion object binary model is obtained by improved minimum Tsallis-cross entropy and morphologic managed. Second, markers of foreground and background for watershed are derived from temporal information, which is used to modify morphological gradient image. Third, watershed segmentation is used to acquire video object with precise boundary. Experimental results show that the proposed algorithm can segment and extract the single, multiple and fast motion object of the video sequence effectively. It has the virtue of low complexity inherited from change detection and watershed and overcomes the defect that it is easy to engender the excessive segmentations of the watershed algorithm, so it has a high adaptability..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 130 (2010)
Calibration for SBUV Corona Detection System
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]
Corona detection via spectral rang in Solar Blind Ultraviolet (SBUV) is an efficient method for power system maintenance. It is necessary to implement luminance calibration for SBUV detection system to ensure the test results’ reliability, including object luminance vs. gain control voltage and object luminance vs. graCorona detection via spectral rang in Solar Blind Ultraviolet (SBUV) is an efficient method for power system maintenance. It is necessary to implement luminance calibration for SBUV detection system to ensure the test results’ reliability, including object luminance vs. gain control voltage and object luminance vs. gray level of the image. The calibrating system was established, which mainly consists of high stable deuterium lamp, integral ball and fiber optic spectrometer. A calibrated ultraviolet deuterium lamp which can be traced back to the American NIST was adopted to calibrate the fiber optic spectrometer, which was used as calibrated detector to calibrate the corona detection system. The relative curve between ICCD gain control voltage and system gain was fitted from the test results and the calibration equation of system was also given. Three experiments with different gain level were implemented to validate the equation. Test results show that the maxim luminance relative error between calculated value and measured value is 6.11% and the Root Mean Square (RMS) is 3.22% when ICCD works in its linear area. Analysis of the calibration scheme shows the uncertainty is 9.1%. It can satisfy the precision requirements of corona detection system. The response characteristics under deferent gain levels of detection system can also be used as a reference in designing auto-gain adjustment algorithm for corona detection..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 135 (2010)
Coupled-wave Analysis, Numerical Calculation and Discussion for Diffraction Properties of Grating
CAI Tuo, SANG Tian, and ZHAO Hua
Rigorous coupled-wave analysis method based on vector theory analysis is derived and discussed by using Maxwell equations and electromagnetic boundary conditions. A general diffraction analysis numerical code based on the Rigorous Coupled-wave Analysis (RCWA) is written so as to design and analyze the diffraction propeRigorous coupled-wave analysis method based on vector theory analysis is derived and discussed by using Maxwell equations and electromagnetic boundary conditions. A general diffraction analysis numerical code based on the Rigorous Coupled-wave Analysis (RCWA) is written so as to design and analyze the diffraction properties of grating, and the diffraction efficiency and the convergence of the RCWA are investigated for the TE mode. The calculated diffraction efficiency is shown to converge to the correct value with an increasing number of space harmonics over a wide range of parameters, including very deep gratings (d/λ>10)..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 141 (2010)
Nanofocusing Element Based on Subwavelength Optical Microcavity
ZHAO Tong-kai, WEI Xing-zhan, and DONG Xiao-chun
A nanofocusing element based on subwavelength microcavity is proposed and demonstrated. Excited surface plasmons wave participates in interference in the microcavity, which results in a standing wave. Subsequently, the energy is coupled into the taper structure, and gives rise to a nanofocusing spot whose FWHM is aboutA nanofocusing element based on subwavelength microcavity is proposed and demonstrated. Excited surface plasmons wave participates in interference in the microcavity, which results in a standing wave. Subsequently, the energy is coupled into the taper structure, and gives rise to a nanofocusing spot whose FWHM is about 100nm. It is found that the localized energy can be modulated by changing the length of surface plasmon microcavity. By using electromagnetic field simulation software FDTD, we characterize the intensity distribution pattern and open out the inner working principle of the element..
Opto-Electronic Engineering
- Publication Date: Oct. 09, 2021
- Vol. 37, Issue 4, 147 (2010)
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