LD-pumped passively Q-switched Nd:YVO/LBO red laser with V:YAG

An LD-pumped Nd:YVO₄ passively Q-switched by V:YAG and intracavity frequency doubled by LBO red pulse laser at 671 nm was presented. With 1.6 W incident pump power, average output power of 53 mW, pulse duration (FWHM) of 29.5 ns, pulse repetition rate of 37.2 kHz, peak power of 48.3 W and single-pulse energy of 1.43 μJ were obtained. The stability of pulse energy and repetition rate was better than 3% for 4 h.     

DPL的声光Q开关衍射特性

利用声光Q开关中衍射效率最大的位置调Q可以发挥其最大性能的特点．研究声光Q开关晶体中超声场的空间分布．得到了晶体中衍射效率的空间分布．从而确定了衍射效率最大的位置．并在实验中得到了与理论分析一致的结果。该结果对大功率激光二极管泵浦调Q固体激光器中Q开关的调节具有实际意义。     

Theoretical study of the electro-optic effect of aperiodically poled lithium niobate in a Q-switched dual-wavelength laser

The electro-optic effect of aperiodically poled lithium niobate (APLN) has been theoretically investigated and proposed to use as a Q-switch in a simultaneous dual-wavelength laser. Our analysis shows that the polarization planes of the z-polarized (or y-polarized) dual-wavelength beams can be simultaneously rotated by 90° through a well-constructed APLN with an external electric field applied along the y-axis, which enables Q-switch function in a dual-wavelength laser cavity. Using a Nd:YVO₄ laser operating at 1.0643 μm and 1.3419 μm as an example, we present a design method of APLN by using the so-called simulated annealing algorithm. The influence of the domain errors in fabricating an APLN device is also studied. The results show that the device is not susceptible to the fabrication errors.     

窄脉冲外差体制CO2激光主动成像研究

根据大目标外差探测时发射功率P_T与距离R₂成正比规律的脉冲激光雷达方程和天线定理,利用国内最新研制的小型高重频电光调Q波导CO₂激光器,采用非线性扫描和激光器不等时发射技术,设计研制了一套窄脉冲外差体制CO₂激光主动成像系统,对室内20m处大目标实现了像元素64×32、成像速率10帧/s实时成像显示,图像质量较好,激光器峰值功率约为60W、脉冲重复频40KHz、前沿50ns、脉宽300ns.     

Characterization of laser-diode end-pumped intracavity frequency doubled, passively Q-switched and mode-locked Nd:YVO4 laser

Simultaneous Q-switching and mode-locking in a laser-diode end-pumped intracavity frequency doubled Nd:YVO₄/KTP green laser using Cr⁴⁺:YAG saturable absorber is experimentally demonstrated. The influence of the initial transmission (T₀) of the Cr⁴⁺:YAG crystal on the Q-switched mode-locked green pulses as well as on the average green power is characterized by using Cr⁴⁺:YAG crystal with various T₀. The effect of T₀ on the pulse build-up time in intracavity second harmonic configuration is theoretically investigated. It was found that the depth of modulation for the mode-locked pulses is greatly improved at the second harmonic wavelength as compared to that for the fundamental wavelength. The average pulse duration of the individual mode-locked pulse for the second harmonic beam measured to be less than 500 ps with a repetition rate of 400 MHz.     

A novel high-peak power double AO Q-switches pulse Nd:YAG laser for drilling

This paper reports on the characterization and analysis of a novel high power with double acousto-optical (AO) Q-switch pulse laser. It is shown that two AO Q-switches, in which acousto-fields are perpendicular to each other, switch-loss is nearly three times larger than one AO Q-switch, one time larger than the two AO Q-switches in which acousto-field are parallel. The laser pulse bursts, with 5–50 kHz repetition rate of the burst, typically 200 ns duration, 400 kW the peak power, 5 mm mrad beam parameter product, are obtained. Using the laser for drilling, the perfect drilling results are given to a thinner recast layer.     

Diode-pumped passively Q-switched intracavity frequency doubled Nd:GdVO4/KTP green laser

A compact diode-pumped passively Q-switched intracavity frequency-doubled Nd:GdVO₄/KTP green-pulse laser was demonstrated, using Cr⁴⁺:YAG as a saturable absorber in a simple flat–flat cavity. With a 5.9 W incident pump power, a passively Q-switched green laser was obtained with an average power of 397 mW, repetition rate of 40 kHz, and pulse width of 40 ns, when the initial transmission of Cr⁴⁺:YAG was 85%. The shortest pulse width of 30 ns, the highest green peak power of 696 W and the maximum pulse energy of 21 μJ were obtained when the initial transmission of Cr⁴⁺:YAG was 70%. Under CW green operation, we obtained 440 mW output power.     

灯泵浦非稳脉冲调Q Nd:YAG固体激光器特性模拟

对实际固体激光器谐振腔的特性分析常常采用经验公式的模型进行预测和研究。从非稳腔衍射积分方程和激光介质速率方程出发，利用GLAD程序计算并模拟了电光调Q非稳折叠腔Nd：YAG激光器的输出光束特性，得到了近场和远场的能量分布以及脉冲宽度波形，计算结果对试验具有指导意义。     

Passive Q-switching of a laser-diode-pumped intracavity-frequency-doubling Nd:NYW/KTP laser with GaAs saturable absorber

Passive Q-switching of a laser-diode-pumped intracavity-frequency-doubling Nd:NYW/KTP laser has been realized with GaAs semiconductor saturable absorber. The dependence of pulse repetition rate, pulse energy, and pulse width on incident pump power are measured. The coupled rate equations are used to simulate the Q-switched process of laser, and the numerical solutions agree with the experimental results.     

高重复频率长寿命电光Q开关驱动电源

用高频金属陶瓷三极管作高压脉冲形成级，设计了一种高重复频率长寿命电光Ｑ开关驱动电源，工作频率可达１ｋＨｚ，输出高压脉冲辐度２．５～８ｋＶ，前沿小于２５ｎｓ。