This paper presents a novel laser⁃induced fluorescence(LIF)Lidar system for marine oil spilling detection.A bifurcated Y⁃type optical fiber and an optical collimating lens compose a coaxial configuration transceiver f...This paper presents a novel laser⁃induced fluorescence(LIF)Lidar system for marine oil spilling detection.A bifurcated Y⁃type optical fiber and an optical collimating lens compose a coaxial configuration transceiver for this LIF⁃Lidar system.This LIF⁃Lidar system was further applied to measure the excitation spectra from floating oil slicks with different thicknesses on top of seawater at different distances.The system presents several advantages such as compact structure,stable optical path,and convenient operation,which offers a wide application prospect in ocean exploration.展开更多
In this letter, we develope a control and image processing system for Streak Tube Imaging Lidar （STIL）. In the system, the data acquisition card control and the software interface are programmed in Visual Basic （VB...In this letter, we develope a control and image processing system for Streak Tube Imaging Lidar （STIL）. In the system, the data acquisition card control and the software interface are programmed in Visual Basic （VB） while the image processing is finished by MATLAB. A STIL imaging experiment is carried out in the laboratory. We obtained the intensity and range images of targets with pseudo color by image processing and reconstruction for a set of raw streak images of targets at different distances acquired by STIL. The range resolution is better than 2 centimeters.展开更多
Optically pumped terahertz （THz） lasers with high pulse repetition frequency are designed. Such a laser includes two parts： the optically pumping laser and the THz laser. The structures of the laser are described a...Optically pumped terahertz （THz） lasers with high pulse repetition frequency are designed. Such a laser includes two parts： the optically pumping laser and the THz laser. The structures of the laser are described and analyzed. The rate equations for the pulsed THz laser are given. The kinetic process and laser pulse waveform for this kind of laser are numerically calculated based on the theory of rate equations. The theoretical results give a helpful guide to the research of such lasers.展开更多
A numerical simulation is performed to study the far-field diffraction properties of planar diamond waveguides.The far-field intensity distributions of a planar air waveguide and a diamond waveguide with different dis...A numerical simulation is performed to study the far-field diffraction properties of planar diamond waveguides.The far-field intensity distributions of a planar air waveguide and a diamond waveguide with different distances are given by numerical calculations.In the experiment,the diffraction patterns on the screen with different distances are recorded using a He-Ne laser as the light source,wherein the laser beam is coupled with and propagates in the diamond waveguide.The simulation results are found to be consistent with the experimental ones.展开更多
In this letter, numerical simulation and experimental study of a radial-slab solid-state laser are presented. The laser includes four crossing-slabs pumped by four Xe flashlamps. The numerical simulation of coherent i...In this letter, numerical simulation and experimental study of a radial-slab solid-state laser are presented. The laser includes four crossing-slabs pumped by four Xe flashlamps. The numerical simulation of coherent intensity in the near field and the far field indicates that the laser with the structure can improve the quality of output beam compared with incoherent beam combination. The radial-slab solid-state laser is fabricated, and initiM experiments are carried out at a pulse repetition of 1 Hz. Nine beams in the near field and one combined beam in the far field are obtained in our initial experiment. The experimental results are consistent with the numerical analysis in the coherent condition. The results show that coherent beam combination is obtained by this laser.展开更多
A new method for laser-frequency stabilization by controlling the pulse setup time is presented. The frequency-stabilization system monitors the pulse setup time continuously, and controls it by adjusting the cavity l...A new method for laser-frequency stabilization by controlling the pulse setup time is presented. The frequency-stabilization system monitors the pulse setup time continuously, and controls it by adjusting the cavity length. Laser frequency is stabilized to the center of the gain curve when the setup time is the shortest. The system is used to stabilize a radio-frequency-excited waveguide CO2 laser tuned by grating, and the shift of laser frequency is estimated to be less than ±25 MHz for an extended period. The system has the advantages of compact structure, small volume, and low cost. It can be applied for frequency stabilization of other kinds of pulsed lasers with adjustable cavity.展开更多
基金Sponsored by the National Natural Science Foundation of China(Grant No.61605033)the Natural Science Foundation of Shandong Province(Grant No.ZR2016FQ24)+1 种基金the Taishan Blue Industry Leadership Program,Project of Shandong Province(Grant No.[2015]1363)the Fundamental Research Funds for the Central Universities(Grant No.HIT.NSRIF.201719).
文摘This paper presents a novel laser⁃induced fluorescence(LIF)Lidar system for marine oil spilling detection.A bifurcated Y⁃type optical fiber and an optical collimating lens compose a coaxial configuration transceiver for this LIF⁃Lidar system.This LIF⁃Lidar system was further applied to measure the excitation spectra from floating oil slicks with different thicknesses on top of seawater at different distances.The system presents several advantages such as compact structure,stable optical path,and convenient operation,which offers a wide application prospect in ocean exploration.
基金supported by the Fundamental Research Funds for the Central Universities(No.HIT.BRET.2010014)the Science and Technology Planning of Shandong Province,China(No.2011GHY11514)
文摘In this letter, we develope a control and image processing system for Streak Tube Imaging Lidar （STIL）. In the system, the data acquisition card control and the software interface are programmed in Visual Basic （VB） while the image processing is finished by MATLAB. A STIL imaging experiment is carried out in the laboratory. We obtained the intensity and range images of targets with pseudo color by image processing and reconstruction for a set of raw streak images of targets at different distances acquired by STIL. The range resolution is better than 2 centimeters.
基金supported by the National Natural Science Foundation of China (No. 60668016)the New Century Foundation for Outstanding Talents from the Ministry of Education of China (No. NCET-07-0240)
文摘Optically pumped terahertz （THz） lasers with high pulse repetition frequency are designed. Such a laser includes two parts： the optically pumping laser and the THz laser. The structures of the laser are described and analyzed. The rate equations for the pulsed THz laser are given. The kinetic process and laser pulse waveform for this kind of laser are numerically calculated based on the theory of rate equations. The theoretical results give a helpful guide to the research of such lasers.
基金supported by the National Natural Science Foundation of China(No.41306092)the Science and Technology Planning of Shandong Province,China(No.2011GHY11514)the Fundamental Research Funds for the Central Universities(Nos.HIT.BRET.2010014 and HIT.NSRIF.2013139)
文摘A numerical simulation is performed to study the far-field diffraction properties of planar diamond waveguides.The far-field intensity distributions of a planar air waveguide and a diamond waveguide with different distances are given by numerical calculations.In the experiment,the diffraction patterns on the screen with different distances are recorded using a He-Ne laser as the light source,wherein the laser beam is coupled with and propagates in the diamond waveguide.The simulation results are found to be consistent with the experimental ones.
基金supported by the Fundamental Research Funds for the Central Universities(Nos.HIT.BRET.2010014 and HIT.NSRIF.2013139)the Scienceand Technology Planning of Shandong Province,China(Nos.2011GHY11514)the Key Laboratory of Functional Crystals and Laser Technology,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences
文摘In this letter, numerical simulation and experimental study of a radial-slab solid-state laser are presented. The laser includes four crossing-slabs pumped by four Xe flashlamps. The numerical simulation of coherent intensity in the near field and the far field indicates that the laser with the structure can improve the quality of output beam compared with incoherent beam combination. The radial-slab solid-state laser is fabricated, and initiM experiments are carried out at a pulse repetition of 1 Hz. Nine beams in the near field and one combined beam in the far field are obtained in our initial experiment. The experimental results are consistent with the numerical analysis in the coherent condition. The results show that coherent beam combination is obtained by this laser.
基金supported by the National Natural Science Foundation of China (No.60668016)the New Century Foundation for Talents of the Ministry of Education of China (No.NCET-07-0240)+2 种基金the Fundamental Research Funds for the Central Universities (No.HIT.BRET.2010014)the Science and Technology Planning of Shandong Province,China (No.2009GG10005006)the Funds for National Key Laboratory of Tunable Laser Technology of China
文摘A new method for laser-frequency stabilization by controlling the pulse setup time is presented. The frequency-stabilization system monitors the pulse setup time continuously, and controls it by adjusting the cavity length. Laser frequency is stabilized to the center of the gain curve when the setup time is the shortest. The system is used to stabilize a radio-frequency-excited waveguide CO2 laser tuned by grating, and the shift of laser frequency is estimated to be less than ±25 MHz for an extended period. The system has the advantages of compact structure, small volume, and low cost. It can be applied for frequency stabilization of other kinds of pulsed lasers with adjustable cavity.
