Journals >Opto-Electronic Engineering
Contents
2012
Volume: 39 Issue 4
26 Article(s)
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Research Article
Application of Active Disturbance Rejection Control in Strap-down North Seeker Speed Stabilization Loop
XIE Mu-jun, TAN Xu-guang, and WANG Zhi-qian
In the running of strap-down north seeker, the friction nonlinearity causes creeping phenomena in the servo system of the turntable in the lower velocity. So the drift of the gyroscope output become larger and the north-seeking precision is affected. In order to achieve the speed stabilization control to ensure fast anIn the running of strap-down north seeker, the friction nonlinearity causes creeping phenomena in the servo system of the turntable in the lower velocity. So the drift of the gyroscope output become larger and the north-seeking precision is affected. In order to achieve the speed stabilization control to ensure fast and stable location of servo-turntable, then to decrease the drift of the gyroscope, an Active Disturbance Rejection Controller (ADRC) is designed and applied in the speed-loop of the servo-turntable. The simulation results compared with PID control show that a fine dynamic performance is obtained, and fast, stabilization and anti-jamming are improved. The results of experiment show that the output signal of Dynamically Tuned Gyroscope (DTG) is more stable, the random drift of DTG is decreased, the north-seeking error is reduced from 34.4″ to 27.7″, and the north-seeking precision is improved effectively..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 1 (2012)
Active Disturbance Rejection Control of Torque Ripple on
Optoelectronic Tracking System
WANG Shuai, WANG Jian-li, LI Hong-wen, and YIN Yu-mei
An improved active disturbance rejection control is proposed to solve the problem on the velocity fluctuation caused by torque ripples in a DC torque motor. The algorithm consists of two parts: the extended state observer estimates the system disturbances, and then the estimated disturbance is fed into the control systAn improved active disturbance rejection control is proposed to solve the problem on the velocity fluctuation caused by torque ripples in a DC torque motor. The algorithm consists of two parts: the extended state observer estimates the system disturbances, and then the estimated disturbance is fed into the control system to form composite correction system. A two-parameter proportional-derivative controller can guarantee system stability and good dynamic characteristics. The simulation and experimental results show that, compared to the PI controller with the same closed-loop control bandwidth, the proposed method can improve the ability of disturbance rejection, using Active Disturbance Rejection Control (ADRC) compensation, the peak-peak value of speed error from 1.88% down to 0.65%, the Root Mean Square (RMS) value of the error from 0.8% to 0.2%. Experimental results show that the proposed method can effectively reduce the velocity fluctuation caused by motor torque ripple, and improve the speed smooth..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 7 (2012)
Automatic Illumination of Microscopic Machine Vision Optimization for Precision Miniature Parts Automatic Assembly System
ZHANG Xi-wen, WANG Xiao-dong, LUO Yi, TENG Lin, and CHEN Liang
In order to always obtain the optimal images of parts in the assembly process, the problem of automatic optimization of microscopic vision illumination intensity was investigated. To realize the illumination of parts edges and surface detail, the illumination automatic control system based on coaxial and ring light souIn order to always obtain the optimal images of parts in the assembly process, the problem of automatic optimization of microscopic vision illumination intensity was investigated. To realize the illumination of parts edges and surface detail, the illumination automatic control system based on coaxial and ring light source was developed. The illumination optimize performance of four types of image quality evaluation function was compared and analyzed, the image quality evaluation methods based on Roberts gradient sum function was proposed and applied in developed assembly systems. The results show that the process of illumination optimization is fast and accurate, the contrast of the target edge is significantly enhanced and the parts recognition error is eliminated after illumination optimization. Moreover, the precision automatic assembly requirements of miniature parts can be met..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 14 (2012)
Active Disturbance Rejection Controller of the Aerial Photography Stabilized Platform
QIU Bao-mei, WAN Ji-quan, and WANG Jian-wen
According to the characteristics of nonlinear and multiple jammers for the aerial photography stabilized platform, an active disturbance rejection detached robust control method is developed. The dynamic equations of the three-axis stabilized platform were deduced based on the Lagrange theorem. Multiple parallel extendAccording to the characteristics of nonlinear and multiple jammers for the aerial photography stabilized platform, an active disturbance rejection detached robust control method is developed. The dynamic equations of the three-axis stabilized platform were deduced based on the Lagrange theorem. Multiple parallel extended state observers were designed for estimation of unknown dynamics and external disturbance of each freedom, and the estimated states were used for nonlinear feedback control and compensation to improve system performance. The simulation and test results demonstrate the ADRVC has good adaptability and robustness to external disturbance and unknown variation. The designed controller not only satisfies the steady accuracy demands, but also effectively resists to the change of the inter and external disturbance. The experimental results show that Active Disturbance Rejection Controller has stronger robustness and adaptability, and demonstrate the feasibility and effectiveness of proposed method..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 21 (2012)
Multi-sensor Data Fusion Tracking Based on Geography Guidance for Airport Target
LU Yu, LIU Chang-zhong, and LIU Peng-fei
In view of the accurate tracking for the airport surface targets, a multi-sensor trajectories fusion method based on geography guidance is proposed to process the data from Automatic Dependent Surveillance – Broadcast (ADS-B) and Multilateration (MLAT). This method deals with the relations among the different sensors uIn view of the accurate tracking for the airport surface targets, a multi-sensor trajectories fusion method based on geography guidance is proposed to process the data from Automatic Dependent Surveillance – Broadcast (ADS-B) and Multilateration (MLAT). This method deals with the relations among the different sensors using distribute filters to realize the trajectories fusion. The process of filtering is under the control of the airport surface geography information and improves the precision through a variable structural multi-model mechanism. Experimental results show that the proposed method has the advantages of both high detection precision and project application value..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 27 (2012)
Effect of Large-scale Structures on Aero-optic Effect
GAN Cai-jun, LI Lang, MAO Tao, XIONG Hong-liang, MA Han-dong, and BI Zhi-xian
To carefully investigate the mechanism of thin light beam aberration passing through compressible mixing layer, double-exposure CCD camera imaging system and schliren system have been used to synchronously measure the flow field and aero-optical aberration. The distribution of density gradation can be obtained by use oTo carefully investigate the mechanism of thin light beam aberration passing through compressible mixing layer, double-exposure CCD camera imaging system and schliren system have been used to synchronously measure the flow field and aero-optical aberration. The distribution of density gradation can be obtained by use of schliren system. In addition, owing to adopting CCD camera imaging system, the aberration images of thin light beam can also be acquired. Moreover, adopting double-exposure technique can present the information of motion and shape of a large-scale structure, and then show its effect on optical aberration. A conclusion from the experimental results can be drawn that the existence of large-scale structure in flow field leads to the tilt and blur of light beam and the motion of large-scale structure results to the corresponding motion of light beam..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 32 (2012)
Location Technology Based on the Extend Cubature Kalman Filter
ZHANG Yang, RUI Guo-sheng, MIAO Jun, and SUN Wen-jun
To improve the accuracy of passive positioning technology and its environmental adaptability, a new nonlinear filter method Extend Square-root Cubature Kalman Filter(SCKF) is offered for multi-station passive location with three moving angle-measured sensors’ measurements. Firstly, Empirical Mode Decomposition (EMD) alTo improve the accuracy of passive positioning technology and its environmental adaptability, a new nonlinear filter method Extend Square-root Cubature Kalman Filter(SCKF) is offered for multi-station passive location with three moving angle-measured sensors’ measurements. Firstly, Empirical Mode Decomposition (EMD) algorithm is used to estimate measurement noise covariance. And then the covariance of the procession noise and measurement noise is brought into the circle procession; At the same time, Cubature Kalman filter (CKF) is improved by the way of square root to keep the stability and positivity, and the results of tracking by Extend SCKF are compared with the results by Unscented Kalman Filter (UKF). By the tracking results to the velocity of the target, Extend SCKF algorithm can not only track the target with unknown measurement noise, but also improve the passive position precision remarkably with the same complexity to UKF..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 37 (2012)
Range Measuring Algorithm for Space Target Based on Radon-Wigner Transform
XU Jian-zhong, LI Li, CHEN Cheng-yao, SUN Ye-qi, and DUAN Ping-guang
According to the question of Radar ranging for the moving target, using the echo characteristic of wideband linear frequency modulated pulse, a method of range measuring for moving target based on Radon-Wigner transform is proposed. In this method, firstly, a mathematic model of stretch processing for moving target scaAccording to the question of Radar ranging for the moving target, using the echo characteristic of wideband linear frequency modulated pulse, a method of range measuring for moving target based on Radon-Wigner transform is proposed. In this method, firstly, a mathematic model of stretch processing for moving target scatter echo is studied. Secondly, according to the superposition of echo and the characteristic of LFM after stretch processing, the parameter of frequency modulation is estimated with the excellent time-frequency concentration performance of Radon-Wigner transform. Finally, the range of moving target is measured. The results show that this method is effective for range measuring of moving target..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 44 (2012)
The Steady Tracking Point Extraction of Target Head
Based on Movement Orientation and Principal Axis
LEI Tao, JIANG Ping, ZHOU Jin, and WU Qin-zhang
In the process of tracking a target with photoelectric tracking system, the target represents the characteristics of extended target when it approaches the tracking device. The size of the target increases rapidly beyond the view of sight, as the distance between the target and the photoelectric tracking device gets neIn the process of tracking a target with photoelectric tracking system, the target represents the characteristics of extended target when it approaches the tracking device. The size of the target increases rapidly beyond the view of sight, as the distance between the target and the photoelectric tracking device gets nearer and nearer. The tracking point jumps or drifts away frequently when using conventional methods such as based on centroid, shape center and correlation tracking, and even lose the tracking. To solve the problem, a steady tracking point extraction method is proposed. It calculates the movement orientation and principal axis of the target. Through tracking the head of the target, it guarantees the background taking up some ratio in the view of sight and avoids failure of segmentation or tracking point drifts away on target when the target beyond the view of sight. The binary morphology method is used for filtering and the shape center of the target head is calculated, which increases the stability of the tracking point on the target head. The simulation test and the experimental results show that the method proposed increases the stability and reliability of the tracking remarkably..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 49 (2012)
Reflective Tomography Lidar Imaging Based on Chirped Pulse Signal
QU Fu-qi, HU Yi-hua, and LENG Jiao-feng
Reflective tomography lidar imaging has the advantage of simple system and is not sensitive to atmospheric turbulence, but ordinary pulse signal is difficult to satisfy the requirement of both high precision and long range. To solve this problem, an imaging processing method based on chirped pulse for reflective tomogrReflective tomography lidar imaging has the advantage of simple system and is not sensitive to atmospheric turbulence, but ordinary pulse signal is difficult to satisfy the requirement of both high precision and long range. To solve this problem, an imaging processing method based on chirped pulse for reflective tomography lidar is presented. In this method, coherent receiving and compression processing is done for chirped pulse echo firstly. Then, projection data of different observation angle is achieved by extracting envelope. At last, high precision image reconstruction is obtained by using Convolution Back-projection (CBP) algorithm. The results of simulation indicate that the envelope obtained by this method is consistent with reflective projection data at the same projection angle, and the outline image of the target can be obtained when the range of projection angle is larger than 60 degree. Imaging experiment validates the feasibility and effectiveness of the presented method..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 55 (2012)
Adverse Effects of Vibration Isolation on Frequency Characteristic of the Photo-electric Tracking System and Suppression of the Effects
YU Wei, MA Jia-guang, TIAN Jing, and XIAO Jing
In allusion to the effect of the vibration isolation on frequency response characteristic of the photoelectric tracking system, a study has been carried out to discover variation laws of the frequency response characteristic, starting with analysis of the dynamics model of the photoelectric tracking system with the vibIn allusion to the effect of the vibration isolation on frequency response characteristic of the photoelectric tracking system, a study has been carried out to discover variation laws of the frequency response characteristic, starting with analysis of the dynamics model of the photoelectric tracking system with the vibration isolation device. Two ideas to suppress adverse effects of the vibration isolation device are presented. One is to modify the design of mechanical structure of the vibration isolation device so as to improve resonance characteristic of the base’s angular motion; the other is to adjust the control strategy of the azimuth axis in order to eliminate negative effects on the tracking control due to swaying of the base. The latter is studied intensively. During the research, the angular position and angular velocity of the base as well as the photoelectric system are measured and the obtained information is used as state variables, which are utilized in the state feedback pole assignment method to remove all resonance poles of the speed response section and cancel the resonance zeros. It is demonstrated in the simulation result that when the state feedback pole assignment method was applied to a photoelectric tracking system installed on the vibration isolation device, with stability as the premise, the amplitude in steady oscillation condition was reduced to 7×10-6 rad from 2.4×10-4 rad. It is concluded that the state feedback method applied to configure the closed-loop desired poles of the speed response section can efficiently suppress adverse effects of the vibration isolation device on the system..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 60 (2012)
Motion Characteristics Analysis of Space Target and
Stellar Target in Opto-electronic Observation
HUANG Zong-fu, WANG Jin-zhen, and CHEN Zeng-ping
In the image sequences obtained by astronomical opto-electronic observation system with large field of view on terrestrial surface, the image characteristics of space targets and large amount of stellar targets are similar, and the main differences between them are their motion characteristics. Firstly, assuming that tIn the image sequences obtained by astronomical opto-electronic observation system with large field of view on terrestrial surface, the image characteristics of space targets and large amount of stellar targets are similar, and the main differences between them are their motion characteristics. Firstly, assuming that the influence of earth rotation can be ignored, the motion characteristics of low orbital space target at different elevation are analyzed. Secondly, the motion characteristics of stellar target at different azimuth and elevation are analyzed based on the foundation of horizontal coordinate system and dependent equatorial coordinate system. At last, the differences of motion characteristics between them are compared, and the results show that the angular velocity of space target is obviously faster than the angular velocity of stellar target and the motion of space target can be considered as uniform rectilinear translation in a short time..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 67 (2012)
Combining and Extending Beam Flat Technology about the Compact Multi-beam Lasers
HAN Xu-dong, CHEN Zhao-bing, WANG Bing, ZHUANG Xin-yu, WANG Heng-kun, and CHEN Ning
The structure design of the high precision and high dependability multi-beam lasers combining beam and extending beam is very important in the engineer appliance. Under this background, the fission foundry benchmark flat was advanced. The brief, middle and long wave band lasers were set in a little box whose length, wiThe structure design of the high precision and high dependability multi-beam lasers combining beam and extending beam is very important in the engineer appliance. Under this background, the fission foundry benchmark flat was advanced. The brief, middle and long wave band lasers were set in a little box whose length, width and height were 1 280 mm、990 mm、815 mm. And this box can be adjusted on space position. The main body structure of laser combining beam and extending beam were designed. At the same time, some important parts were analyzed by using the finite buck statics software. The adjusting mete of the angle on the laser outgoing direction in the flat is bigger than ±30′, and the flatchief mass is about 600 kg. Under the precondition that the transition benchmark flat system bearing the weight of the flat load, its maximum deformation strain meeting an emergency is 0.005 mm. It can be indicated that this structure can satisfy this kind laser combining beam and extending beam and adjusting request in small space. This method can be extended to other light way about combining beam and extending beam structure design..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 73 (2012)
Analysis and Test of Tracking Angle Error for Semi-active Laser Seeker
XING Hui, LEI Ping, Lü Hong-peng, and ZHANG Lei
Based on target detecting principle of semi-active laser seeker, a new test method is put forward which use windage account model for four quadrant detector of target station and detector signal test error model with the coincidence. It are calculated and well demonstrated for test. Test result indicates that the circuBased on target detecting principle of semi-active laser seeker, a new test method is put forward which use windage account model for four quadrant detector of target station and detector signal test error model with the coincidence. It are calculated and well demonstrated for test. Test result indicates that the circuit of windage account for target station is primary when target is located out of tracking region, and the coincidence of windage account for target station is primary when target is located in center of tracking region. Capability of tracking and the value about test of laser seeker in future is analyzed..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 78 (2012)
Design of Programmable Control Integrated YAG Laser
WANG Wei-feng, LIU Zhi-guo, WANG Shi-cheng, LIU Yuan, and ZANG Yong-qiang
Taking the Hardware-in-the-loop (HWIL) simulation of laser guided weapons as the background, we studied the laser target simulator in the paper, a suit of high precision and real-time laser target simulator was designed. The composition and design of the laser were discussed, focusing on the system of energy attenuatorTaking the Hardware-in-the-loop (HWIL) simulation of laser guided weapons as the background, we studied the laser target simulator in the paper, a suit of high precision and real-time laser target simulator was designed. The composition and design of the laser were discussed, focusing on the system of energy attenuator and controllable telescope. Experimental results show the laser simulator can simulate the energy and size of laser facular, and meet the need of HWIL of laser guided weapons..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 84 (2012)
Enhancement of Goos-H.nchen Shift with Cascade Optical Waveguides
RAN Mao-wu, CHEN Fan, CAO Zhuang-qi, and CHEN Xian-feng
According to the previous study, we have proved that, by using the symmetrical metal-cladding optical waveguide with millimeter scale and the free-space coupling technique, one millimeter order of Goos-H.nchen shift can be obtained due to the resonance effects and the increase of the penetration depth. On the basis of According to the previous study, we have proved that, by using the symmetrical metal-cladding optical waveguide with millimeter scale and the free-space coupling technique, one millimeter order of Goos-H.nchen shift can be obtained due to the resonance effects and the increase of the penetration depth. On the basis of this, enhancement of Goos-H.nchen shift is demonstrated with a pair of symmetrical metal-cladding optical waveguides in a cascaded structure. It is experimentally shown that the Goos-H.nchen shift measured from a CCD detector is 2215 μm with a change of 43 pm in the light wavelength, which is just two times of that exhibited from a single waveguide. Experimental result agrees well with the theoretical prediction. This method shows potential application prospect in optical switching and filtering..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 91 (2012)
Tunable Filtering Scheme and Characteristics Analysis
Based on Photorefractive Gratings
ZHANG Ming, MENG Hui-yun, CHEN Liu-wei, and LE Zi-chun
Photorefractive waveguide grating can be formed using two-beam interference method in lithium niobate with the single-mode waveguide. A scheme for Coarse Wavelength Division Multiplexing (CWDM) is proposed to realize tunable filter by changing the angle between the two recording beams which changes the grating pitch. WPhotorefractive waveguide grating can be formed using two-beam interference method in lithium niobate with the single-mode waveguide. A scheme for Coarse Wavelength Division Multiplexing (CWDM) is proposed to realize tunable filter by changing the angle between the two recording beams which changes the grating pitch. With photorefractive dynamics, tuning time of several milliseconds is obtained. It is found that diffraction efficiency can be increased and the building time decreased by suitable intensity and dopant. The results based on coupled wave theory show that diffraction efficiency can be increased and bandwidths narrowed when the grating length is increased, and diffraction efficiency can be increased but bandwidths widened with the increasing refractive index modulation. When refractive index modulation is 8×10-5 and the grating length is longer than 12 mm, diffraction efficiency more than 91% and bandwidth narrower than 0.08nm can be obtained..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 96 (2012)
The Refractive Index Sensoring Characteristics of
Polarization Maintaining Microstructured Optical
Fiber Grating Based on Fabry-Perot Cavity
GUO Xuan, BI Wei-hong, and LIU Feng
To enhance the stability of the fiber grating refractive index sensor and increase the grating reflectivity, the Polarization Maintaining Microstructured Optical Fiber (PM-MOF) grating Fabry-Perot (F-P) cavity is proposed. Based on Finite Element Method (FEM) and Transfer Matrix Method (TMM), the refractive index sensiTo enhance the stability of the fiber grating refractive index sensor and increase the grating reflectivity, the Polarization Maintaining Microstructured Optical Fiber (PM-MOF) grating Fabry-Perot (F-P) cavity is proposed. Based on Finite Element Method (FEM) and Transfer Matrix Method (TMM), the refractive index sensing characteristics of the sensor is analyzed. The relationship between the refractive index and resonant wavelength difference is simulated. Moreover, the dependence of the reflection spectrum on the center big holes size and the F-P cavity length is studied. Since two polarization modes respond similarly to the outside perturbation, the fiber possesses high stability. Based on the interference, the reflectivity is enhanced obviously, and almost remains unchanged as the analyte refractive index increasing. It is beneficial for the detection. The results provide the theoretical basis for the application of PM-MOF grating in the optical fiber refractive index sensor and the optical fiber label-free biosensing..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 102 (2012)
An Optical Orthogonal Heterodyne Demodulation Technology for
Interferometric Fiber-optic Sensor
OU Jian-hai, XU Kai, ZHOU Yue, LI Dong, JIN Xiao-feng, XU Wen, WANG Shi-quan, ZHANG Jun, and WANG Yue-bing
According to the mechanism of the interferometric fiber-optic sensor, an optical orthogonal heterodyne demodulation technology has been investigated in this paper. A variable fiber delay line was used to adjust the optical phase delay to obtain optical orthogonal heterodyne demodulation, so that the low-frequency noiseAccording to the mechanism of the interferometric fiber-optic sensor, an optical orthogonal heterodyne demodulation technology has been investigated in this paper. A variable fiber delay line was used to adjust the optical phase delay to obtain optical orthogonal heterodyne demodulation, so that the low-frequency noise in the photo-detector can be reduced. Comparing with the conventional heterodyne demodulation schemes, the additional noise as well as temperature-related drift induced by the electronic phase drift devices can be eliminated by using the proposed demodulation technology. An experiment system was set up to measure the optical phase change induced by the piezoelectric ceramic (PZT) vibration. The result shows that the proposed scheme can demodulate the sensing signalefficiently, and a minimum detectable phase shift of 9.2×10-5 rad can be achieved..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 108 (2012)
Characteristics of Time Response for Waveguide Absorption Cell
LU Wei-jia, ZHOU Jia-qi, ZHAO Hua-xin, and SHI Yi-wei
Optical waveguides have a promising application as absorption cells in concentration measurement for gases. Mechanism and properties of the time response for the waveguide absorption cell were theoretically analyzed based on the diffusion and hydrodynamic theories. Two measuring systems corresponding to the diffusion aOptical waveguides have a promising application as absorption cells in concentration measurement for gases. Mechanism and properties of the time response for the waveguide absorption cell were theoretically analyzed based on the diffusion and hydrodynamic theories. Two measuring systems corresponding to the diffusion and hydrodynamic applications were established by using Fourier transform infrared spectroscopy (FTIR) equipment, Ultraviolet and visible (UV-VIS) spectroscopy and specially fabricated low-loss hollow fiber as the absorption cell. A modified calculation model was proposed based on the measured data of dynamics methane and toluene gas flow at low concentration level. Experimental results show that response time can be dramatically shortened by optimizing the structure of the waveguide cell while maintaining a high sensitivity in gas sensing. And the characterization results provide useful guidance for the design and application for gas sensor using hollow waveguides as absorption cells..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 114 (2012)
Effects of Low Intensity Laser Irradiation with Combination of 635 and 808 Nanometers on Surgery Wound Healing
YANG Ji-chun, LI Ying-xin, LIU Tie-gen, MA Wen-jiang, MA Hui, and ZHANG Hai-bo
In order to provide a reference for clinical applications, effects of Low Intensity Laser Irradiation(LILI) withcombination of 635/808nm on cutaneous wound healings are evaluated. Non-surgical treatment of 60 patients with malignant tumors, the test group and control group of 30 cases is randomly selected. The incisionIn order to provide a reference for clinical applications, effects of Low Intensity Laser Irradiation(LILI) withcombination of 635/808nm on cutaneous wound healings are evaluated. Non-surgical treatment of 60 patients with malignant tumors, the test group and control group of 30 cases is randomly selected. The incision site of patients has been irradiated with laser, which generated two lasers. One was red laser with wavelength at 635 ± 5nm and power density at 1~6.5 mW/cm2; the other was infrared laser with wavelength at 808 ± 5nm and power density at 11~32 mW/cm2. Laser treatment was started 24 hours after the end of surgery, each Days once every 15 minutes exposure to treatment endpoint. He-Ne laser treatment began 24 hours after the end of surgery, day 1, each exposure 15 minutes, until the end of treatment (hospital or wound healing stitches). The result shows that LILI with the combination of 635/808 nm could improve cutaneous wound healings of patients significantly rather than using He-Ne laser..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 121 (2012)
Digital Simulation of Diffraction Optical Elements
Based on Diffraction Angular Spectrum Theory
YIN Ke-wei, HUANG Zhi-qiang, LIN Wu-mei, and XING Ting-wen
Digital simulation of optical experiment has been more widespread in resent years. In this paper, diffraction angular spectrum theory is used to calculate the intensity distribution of the diffractive optical elements. This theory can be expressed by transform function, and also can be expressed by point spread functioDigital simulation of optical experiment has been more widespread in resent years. In this paper, diffraction angular spectrum theory is used to calculate the intensity distribution of the diffractive optical elements. This theory can be expressed by transform function, and also can be expressed by point spread function. However, two expressions vary inMATLAB. We could divide them into near field simulation method and far field simulation method. A consequence of experiment is given and discussed. It shows that they can calculate distribution of illumination in different diffractive distances accurately. These methods are important for diffraction simulations..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 125 (2012)
Optical Proximity Correction for Low Resolution
Acoustooptic Modulator
ZHANG Shan, and WANG Lei
In order to efficiently correct the optical proximity effect in Laser Direct Writing (LDW), a correction method for low resolution acoustooptic modulator is proposed. Firstly, based on Iterative Error-Correction Method (IECM) proposed by Rajesh Menon, one virtual high resolution acoustooptic modulator is used to correcIn order to efficiently correct the optical proximity effect in Laser Direct Writing (LDW), a correction method for low resolution acoustooptic modulator is proposed. Firstly, based on Iterative Error-Correction Method (IECM) proposed by Rajesh Menon, one virtual high resolution acoustooptic modulator is used to correct the direct writing pattern, and the exposure data obtained are converted and rounded to that corresponding to the low resolution acoustooptic modulator, then the exposure data of spots nearest to each error area barycenter are modulated, and the above steps help IECM correct the optical proximity with low resolution acoustooptic modulator and make a thorough optimization. Experimental results indicate that, taking “L” design pattern as example, compared with IECM unable to correct the direct writing pattern with low resolution acoustooptic modulator, the proposed method in this subject can be used to correct the direct writing pattern, which decreases pattern error value by 70.88% relative to the initial error value..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 129 (2012)
A Multi-core DSP Image Processing System Based on Optical Fiber Transmission Real-time
SUN Ke-lin, ZHOU Wei-chao, WU Qin-zhang, and PENG Zhen-ming
To solve the bottleneck problem of high-speed, high-resolution real-time image transmission and processing on photoelectric theodolite, a framework of real-time image transmission based on optical fiber and FPGA + multi-core DSP processing unit is proposed, which means this design realized high-speed image transmit to To solve the bottleneck problem of high-speed, high-resolution real-time image transmission and processing on photoelectric theodolite, a framework of real-time image transmission based on optical fiber and FPGA + multi-core DSP processing unit is proposed, which means this design realized high-speed image transmit to multi-core DSP processing unit in real time. On this basis of that, a custom protocol of image transmission on optical fiber has been developed by using the protocol to interconnect image processing unit between various subsystems, such as displaying subsystem and recording subsystem. A collectivity design of system, hardware design and software design of system are described, especially designs of image transmission protocol and multi-core DSP processing unit, which are introduced in detail to build an experimental platform, test and analyze the system. Extensive experiments on the whole system validate that, real-time image transmission to subsystems gets rate at 2.5 Gb/s by optical fiber channel, and transmission gets rate at 3.125 Gb/s between the multi-core DSP and FPGA on multi-core DSP image processing unit. The system is stable, reliable and low error rate. It has advantages such as strong processing capacity, strong performance of anti-electromagnetism interference. This system has been applied in engineering projects..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 136 (2012)
Driver of Multiplying Clock with Adjustable Amplitude for EMCCD
CHEN Su-guang, ZHANG Tao, ZHENG Wei-bo, and YUAN Shi-dong
According to multiplication gain plot and multiplying clock power of CCD97, a new driver circuit was designed to generate square multiplying clock with adjustable amplitude for multiplying imaging of CCD97. The driver contained an isolated push-pull circuit and an adjusted power. The former generated square clock and tAccording to multiplication gain plot and multiplying clock power of CCD97, a new driver circuit was designed to generate square multiplying clock with adjustable amplitude for multiplying imaging of CCD97. The driver contained an isolated push-pull circuit and an adjusted power. The former generated square clock and the latter adjusted amplitude of the clock. With the increase of amplitude, the adjusting resolution increased, which partly compensated the nonlinearity of multiplication gain plot. Both multiplying clock waveform and multiplying image driven by the driver were given at the end of this article. The result shows that the driver circuit can provide right clock to CCD97 for multiplying imaging and gain adjusting..
Opto-Electronic Engineering
- Publication Date: Jan. 01, 1900
- Vol. 39, Issue 4, 145 (2012)
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