Electro-Optic Technology Application
Co-Editors-in-Chief
Bing Han
LIANG Zhi-qiang

A frequency stabilized single longitudinal mode (SLM) laser is widely used in coherent detection, high-accuracy laser ranging, high-resolution spectrum, laser radar, etc. TEA CO2 laser seed injection technique is researched theoretically and experimentally. The SLM TEA CO2 laser output is obtained through frequency stabilized seed laser injection design. The preliminary experimental research is performed to obtain SLM laser output with 100 mJ single pulse energy and 10.59 μm (10P20) output laser wavelength, which is the same as the injection seed laser wavelength, and the experimental results are analyzed. In this method, the wavelength, far field beam divergence angle, frequency stability and M2 factor of the output laser are the same as those of the seed laser, so if a high beam quality seed laser source is used, a high-power output of the laser with high frequency stability and high beam quality will be got, and it is significant to scientific and national defense use.

Jan. 01, 1900
  • Vol. 32 Issue 2 1 (2017)
  • Jan. 01, 1900
  • Vol. 32 Issue 2 1 (2017)
  • CAI Jun, and DING Yu

    A Tm:YAP slab laser with double-end-pumped and high power under room temperature is introduced. With double concave cavity structure and optimizing pumping facula size, F-P etalon is inserted in the cavity to control laser wavelength. When pumped power is 164.4 W, 54.7 W continuous output power is obtained, the slop efficiency is 44.2% and the output wavelength is 1 938.8 nm. With the increasing of the power, the output wavelength only has 0.3 nm shift and the laser output for 0.18 nm narrow line width is realized. And the optical beam quality is measured when pumped power is 10 W, 25 W and 35 W, which is 3.5, 4.1 and 4.2 respectively.

    Jan. 01, 1900
  • Vol. 32 Issue 2 9 (2017)
  • GAO Xue-peng, and WANG Kai

    The fast steering mirror (FSM) is one of the core parts in the composite axis precision tracking system. In order to research the beam deflection caused by decoupling FSM rotation, the FSM rotation is decomposed into longitudinal and transverse movement, and the space rectangular coordinate system is established. Rotating the FSM longitudinally and transversely, the cardinal relationship of the angular variation of the reflection rays in the FSM coordinate system is established theoretically. Based on the typical models, the simplified model in the azimuth and pitch direction is constructed. In this way, the engineering calculation could be simplified, and the results are verified through simulation experiments.

    Jan. 01, 1900
  • Vol. 32 Issue 2 15 (2017)
  • LI Qing-xuan, YANG Xu, and QIN Wen-bin

    The reflected laser damage has affected the further application of high power diode lasers in industry processing. It is very important to the research on the problem of reflected laser damage technology for solving the problem of the high power diode lasers in industrial application. The active anti-reflective laser damage of the high power diode lasers is realized based on the line polarized laser characteristic of diode laser and using the combination device of polarized beam splitter and λ/4 wave plate. The reflective laser intensity is monitored by the electro-optic monitoring unit. When the reflective laser intensity is higher than the damage threshold, the laser output is closed to realize the passive anti-reflective laser damage. The anti-reflective laser damage device with both active and passive anti-reflective laser damage functions is researched which can be used in the high power diode laser of industrial processing.

    Jan. 01, 1900
  • Vol. 32 Issue 2 21 (2017)
  • YI Yu-feng, and TIAN Hong

    The traditional methods for the detection of the small dim targets could not detect the small dim targets accurately and efficiently in IR image sequence with complex background. A novel algorithm for detecting small dim target is proposed to solve the above problems. Through analyzing the infrared radiation characteristics and sequential motion characteristics of the small dim targets in IR image sequence, the difference between the small dim targets and interference points can be found. The candidate targets can be detected by searching maximum gray pixels, removing noise, removing the targets with slowly intensity change and removing the targets without having a 2D Gaussian distribution. The spatial-temporal pipeline is designed according to target position change. The position of the targets in the next frame could be predicted along the direction of the spatial-temporal pipeline. The real targets can be detected according to the energy change and area change of the targets in the IR image sequence. Experimental results show that the accuracy and efficiency of our proposed method is improved significantly comparing with the traditional small dim targets detection methods.

    Jan. 01, 1900
  • Vol. 32 Issue 2 25 (2017)
  • ZHANG Hua, and ZHANG Hai-bin

    With the development of infrared technology, infrared sensors are widely used in various fields such as monitoring, security checking and target tracking. In some special occasions, for example unmanned aerial vehicle (UAV) acquiring target information, the whole process is needed to be record to prepare for the subsequent analysis, treatment and comparison with other samples, so as to get more information. According to above requirements, the infrared image storage and a playback system based on FPGA+DSP architecture are designed. And bad block management for memory chip is performed to ensure the reliability of the memory. Image data is sent to the host computer through Gigabit Ethernet to complete data offload and playback.

    Jan. 01, 1900
  • Vol. 32 Issue 2 32 (2017)
  • YANG Cheng, SU Bo, and ZHAO Peng

    Camera control software is designed based on LabVIEW 2009 in electro-optical detection system in order to control TV and infrared camera working mode and the capturing and processing of the detected images. The camera setup subprogram is designed according to the character of serial communication control, and the camera working mode is set up by sending different commanding codes. Capturing and processing subprogram are complied to realize display of video image in real time after capturing, despinning and display processing. Application results show that the camera is controlled by the program flexibly and the effect of output video images is satisfied.

    Jan. 01, 1900
  • Vol. 32 Issue 2 36 (2017)
  • XIE Hong, and PU Jin-long

    From the basic conception and the recognition frame of Dempster-Shafer (D-S) evidential theory, a new construction algorithm to basic probability assignment function based on sensor characteristics is proposed. The fuzzy membership for different target identity of the sensing signals from the sensors is processed to obtain the judging precision, which is used as the basic probability assignment function value to perform D-S evidence fusion. An example for the simulations of target recognition focused on three types of sensors is presented, the results show that the method is good to improve the reliability of the target recognition and decreases the uncertainty.

    Jan. 01, 1900
  • Vol. 32 Issue 2 41 (2017)
  • LI Xue-jiao, JIANG Yue-qiu, LI Wei-shuai, and GAO Hong-wei

    Due to the traditional contact measurement method which needs to contact with components and the limitations such as measurement time and human factor, a large-scale component measurement system based on machine vision has been developed to meet the non-contact, fast measurement speed, high measurement precision, real-time display and other measurement requirements. Firstly, in the large-scale component measurement system based on machine vision, the collected images are pretreated. Wavelet denoising method is used to finish the smooth denoising of the images in view of the existence of noise and other factors. Secondly, the scale invariant feature transformation (SIFT) algorithm is selected for image registration, the weighted average fusion algorithm based on the weighted average of the hat function is used to complete the image fusion without gaps, thus image mosaic is completed. And then, an improved single pixel edge detection method is proposed to extract the edge contour of the component image based on the Canny detection operator. Finally, geometrical experiment measurement is performed to the edge contour of the extracted images and the experimental data are analyzed. The large-scale component measurement system based on machine vision has simple operation, inexpensive price and the size of the component can be measured quickly within the allowable range of error.

    Jan. 01, 1900
  • Vol. 32 Issue 2 44 (2017)
  • HUANG Wei, and PANG Jian-ying

    The optical and mechanical structure of the position solution testing equipment is more complex, the equipment needs to be calibrated after the installation of visible optical axis and laser optical axis. A kind of simulation calibration method for the detection optical axis of the position solution testing equipment based on the principle of parallel to the optical axis is designed. The composition and the calibration principle of the system are introduced in detail. The results show that the calibration method has the advantages of high precision, simple system layout, facile operation, and can quickly and accurately realize the purpose for the optical axis simulation calibration of the position solution testing equipment.

    Jan. 01, 1900
  • Vol. 32 Issue 2 49 (2017)
  • HAO Jian-xin, and TAN Li

    Insulated gate bipolar transistor (IGBT) drive protection circuit is taken as the interface circuit between the inverter main circuit and the control circuit. It is very important for the inverter to design a good drive protection circuit in normal operation. Traditional inverter drive circuits only rely on software to set the dead zone protection time to avoid the phenomenon that the up bridge and down bridge of the same phase simultaneously turned. Through this circuit, once the software runs error, it is likely to cause the IGBT up bridge and down bridge simultaneously turned and blows up the inverter. A new inverter drive circuit with hardware interlock function is described. In this new drive circuit, the inverter bridge drive opto-coupler is driven by a group of differential pulse width modulation (PWM) signal. The two opto-couplers for the up bridge and down bridge of the same phase bridge arm in the driving circuit are driven by the same group opposite logic differential PWM signal. The hardware interlock function of the inverse bridge drive circuit is realized to avoid the phenomenon of both the up and down bridge simultaneously turned and the reliability of the inverter drive circuit is improved greatly.

    Jan. 01, 1900
  • Vol. 32 Issue 2 54 (2017)
  • SHEN Cai-ying, and ZOU Ying

    The issue of the regular energy consume for the voltage balance circuit is analyzed. To obtain wide range dynamic balance voltage, both DC/DC converter and gap delay combination control mode are introduced to the ultra capacitor voltage balance circuit. The boost converter is used to achieve voltage balance from lower side ultra capacitor C2 to higher side ultra capacitor C1. Correspondingly, the evolved care unite skin (CUK) converter is used to achieve voltage balance from high side ultra capacitor C1 to low side ultra capacitor C2. Experimental results verify the effectiveness of zero loss voltage balance circuit.

    Jan. 01, 1900
  • Vol. 32 Issue 2 58 (2017)
  • MA Tao, and GENG Min

    Mathematical models such as target infrared characteristic, atmospheric transmission characteristic and detecting range are analyzed and established. In order to simulate the infrared target detection in the battlefield, the models are also verified and improved by test data. The simulation could be used in tactical training, tactical research and validation, which will achieve the purpose of improving the integrative combat ability of the platform.

    Jan. 01, 1900
  • Vol. 32 Issue 2 62 (2017)
  • SI Han-ying, and CAO Feng-jiang

    Based on heat conduction theory, the heat conduction equation of slab and bulk crystals is established. Making solution for heat conduct equation and numerical simulation, the temperature distribution, thermal stress and thermal lens effect of the Tm:YLF of slab and bulk crystals is analyzed comparatively in the condition of high pumping power. The calculated results indicate that the slab crystal is more suitable for the output of high power laser. The necessary theoretical guidance is provided for developing the laser power.

    Jan. 01, 1900
  • Vol. 32 Issue 2 68 (2017)
  • WANG Duo

    IR small target detection is always one of the topic difficulties, and it is easy to be covered by the background due to many factors. The IR small target detection is very difficult for the complicated background and stealthy technology application. With scale-space theory, the characteristics of IR images of the IR small target in the energy field are analyzed. Multi-step energy difference is used to determine the center point and the size of the target. Based on the characteristics of noise and target point, the isolated noise points in the results are rejected to inspect the small target finally. Experimental results show that the algorithm has simple calculation, short running time and can inspect the target effectively.

    Jan. 01, 1900
  • Vol. 32 Issue 2 73 (2017)
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