Laser diode array side-pumped acousto-optic induced unidirectional operation Q-switched Nd : YAG slab ring laser

A laser-diode array (LDA) side-pumped Nd:YAG slab ring laser is described that incorporates a prism-shaped acousto-optic modulator to enforce unidirectional operation and Q-switching. When pumped by the maximum power of 50 W, Q-switched energies of 3.6 mJ and 50 ns duration, corresponding to a peak power of 72 kW, are obtained. (C) 1999 Society of Photo-Optical Instrumentation Engineers. [S0091-3286(99)01306-9].

Smoothing the side lobes of a focused pattern by spectral dispersion in the broadband laser

Starting from the Huygens-Fresnel diffraction integral, the propagation equations of a broadband laser passing through a dispersive lens and a dispersive wedge are derived. Smoothing effect on the side lobes of the focused pattern is achieved as the broadband laser passes through the lens because of the spectral dispersion of the lens. By inserting a dispersive wedge behind the lens, better smoothing effect is realized because a relative position shift between focused patterns of different frequency components is generated due to the spectral dispersion of the wedge. Smoothing effect on the side lobe is obtained even with small bandwidth of the broadband laser as the wedge is used. (c) 2006 Elsevier GmbH. All rights reserved.

机载测深激光雷达千赫兹全固态激光器设计及特性研究

将千赫兹高功率全固态Nd：YAG激光器的增益介质当作厚透镜处理，使用矩阵的方法对等效热透镜腔进行分析。采用多条半导体激光列阵侧向紧凑抽运结构设计，提高了增益介质光抽运的均匀性。根据实际抽运功率，通过模拟计算，设计了平凸非稳腔。选择的凸面全反镜的最佳曲率半径有效地补偿了增益介质热透镜效应，激光器实现了动态稳腔运转，激光脉冲能量输出斜度效率大于13％，光束发散角优于1.3mrad。

高重复率半导体激光抽运Nd：YAG放大器激光特性的实验研究

实验研究了高重复率、大功率半导体激光二极管阵列（LDA）侧面环绕抽运的Nd：YAG激光放大器的放大特性、热焦距变化和热致双折射效应引起的退偏特性。偏振光绎千赫兹高功率单通激光放大器，获得约3倍的光脉冲能量放大，脉冲宽度基本保持不变，其输出的P分量与S分量的能量比趋于常数3：1，实验测得的能量放大倍率及放大光束的椭圆偏振度与理论预期吻合很好。

千瓦级半导体抽运的固体热容板条激光器

报道了千瓦级激光二极管面阵抽运固体热容激光器的理论与实验研究, 分别采用Nd:YAG单板条和双板条串接的热容激光器, 利用热容激光器的理论计算模型计算了在一定的工作时间内激光输出特性, 并进行了实验验证。实验中采用的晶体尺寸均为59 mm×40 mm×4.5 mm, 对单板条进行抽运时平均功率大约为5.6 kW, 双板条串接时为11.2 kW, 重复频率为1 kHz, 占空比为20％。实验中观察了1 s的工作时间内脉冲能量输出的波动情况, 单板条时单脉冲能量输出最大为1.3 J, 在1 s后单脉冲能量输出

LD侧面泵浦固体激光器泵浦光分布模拟

利用Gauss光束通过光学系统的变换规律,将激光二极管阵列发出的光作为Gauss光束处理.应用矩阵光学方法,解析分析与数值模拟相结合,给出了激光二极管阵列侧面泵浦棒状固体激光介质内泵浦光的强度分布.比较了侧面环绕激光二极管阵列数量不同时泵浦光分布的均匀性;以及考虑准直系统后,不同准直透镜焦距时,晶体内泵浦光半径的大小;同时针对泵浦光在晶体内聚焦时的情况进行了简单讨论.将半解析法与光线追迹法所得结果进行了比较,二者十分相近,但前者计算要简单得多.

热畸变对单板条热容激光器输出的影响

开展了激光二极管(LD)抽运的全固态热容激光器的理论与实验研究, 数值模拟了在热容工作条件下侧面抽运的Nd:YAG板条激光器的热透镜效应, 分析了热透镜效应对激光输出的影响, 并进行了相应的实验论证。实验中采用的晶体尺寸为57 mm×40 mm×4 mm, 激光二极管阵列的抽运峰值功率为12 kW, 重复频率为1 kHz, 占空比为20%, 为了获得较高的增益, 将抽运光通过光学系统进行聚焦, 抽运光在晶体侧面的光斑大小为15 mm×57 mm。实验中观察了1 s内的脉冲能量输出的波动情况, 在开始工作的

High-energy LDA switched side-pumped electro-optical Q-switched Nd : YAG ceramic laser

By employing a uniformly compact side-pumping system, a high-energy electro-optical Q-switched Nd:YAG ceramic laser has been demonstrated. With 420 W quasi-cw laser-diode-array pumping at 808 ran and a 100 Hz modulating repetition rate, 50 mJ output energy at 1064 nm was obtained with 10 ns pulse width, 5 W average output power, and 5 MW peak power. Its corresponding slope efficiency was 29.8%. The laser system operated quite stably and no saturation phenomena have been observed, which means higher output energy could be expected. Laser parameters between ceramic and single-crystal Nd:YAG lasers have been compared, and pulse characteristics of Nd:YAG ceramic with different repetition rate have been investigated in detail. The still-evolving Nd:YAG ceramics are potential super excellent media for high-energy laser applications. (C) 2007 Optical Society of America.

Depolarization loss compensated resonator for electro-optic Q-switched solid-state laser

A novel laser resonator for compensating depolarization loss that is due to thermally induced birefringence in active rod is reported. As this new structure being applied to an electro-optic Q-switched LIDA side-pumped Nd:YAG laser operating at a repetition rate of 1000 Hz, substantial reduction in depolarization loss has been observed, the output pulse energy is improved about 56% from that of a traditional resonator without compensation structure. With incident pump energy of 450 mJ per pulse, linearly polarized output energy of 30 mJ per pulse is achieved, the pulse duration is less than 15 ns, and the peak power of pulse is about 2 MW. The extinction ratio of laser beam is better than 10:1, and the beam divergence is 1.3 mrad with beam diameter of around 2.5 mm. (c) 2006 Published by Elsevier B.V.

CW-pumped evanescent amplification based on side-polished fiber with heavily Er3+-doped glass overlay

A novel diffractive-pumping scheme is proposed to improve the evanescent amplification using blazed fiber grating for the first time. We also investigate the cw-pumped-evanescent amplification at 1.55 mu m wavelength with the relative optical gain pumped at 1480 nm of around 2 dB based on side-polished fiber with the effective interaction length as long as 16 mm and with a heavily Er3+-doped (N-Er(3+) > 1.19 x 10(21) ions/cm(3)), low refractive index (n(1550) < 1.47) glass overlay, which has no concentration quenching (tau(f) = 9.0 ms).