共查询到19条相似文献,搜索用时 187 毫秒
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热透镜效应下的克尔透镜锁模 总被引:2,自引:1,他引:1
讨论了在增益介质与克尔介质分离情况下热透镜效应对克尔透镜锁模的影响,计算了克尔透镜锁模在热不敏感腔中需满足的条件,结果表明,通过适当地调整激光腔参数,有可能实现热不敏感的克尔透镜锁模。最后通过计算机数值模拟获得了对典型振荡腔设计参量的修正。 相似文献
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环境磁场的干扰是影响激光陀螺精度的重要因素之一. 为了减小二频机械抖动激光陀螺的磁敏感性, 推导了环形腔的琼斯矩阵, 其中考虑了非共面角、增益介质、腔损耗、腔镜反射各向异性和应力双折射, 采用矩阵本征问题求解的摄动理论分析了环形腔的偏振态和磁敏感特性. 研究表明, 为了减小激光陀螺的磁敏感性, 应减小非共面角和腔损耗, 增大腔镜的反射各向异性. 腔镜应力双折射究竟会增大还是减小磁敏感性与应力作用主轴、受应力腔镜的位置有关, 此外它还会引起顺时针和逆时针模式之间的偏振非互易性. 磁敏感性与腔失谐近似成线性关系, 导致激光陀螺工作于增益峰值时磁敏感性并非最小. 这些结果对减小二频机械抖动激光陀螺的磁敏感性具有较好的指导意义.
关键词:
激光陀螺
磁敏感性
椭圆度
琼斯矩阵 相似文献
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为了产生频差可调谐1 064nm双频激光输出,设计了一种扭转模结构双腔双频Nd∶YAG激光器,其两个驻波谐振腔共用相同的Nd∶YAG增益介质,以扭转模结构消弱增益空间烧孔效应,使Nd∶YAG激光器的两个驻波腔均以单纵模振荡,从而获得正交线偏振1 064nm双频激光输出.理论分析了扭转模结构激光单纵模选择原理和双频激光同时振荡原理,实验研究了双频激光振荡特性和频差调谐特性.研究结果表明:双频Nd∶YAG激光器的两个谐振腔能够同时以线偏振单纵模稳定振荡输出,其频差大小可随激光腔长的改变而调谐,频差调谐范围可达1个纵模间隔,实验观察到的频差调谐范围为0.3GHz~3GHz. 相似文献
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研究了不同腔镜结构不同失调情况对空间谐振式激光陀螺中光束空间位置的影响.利用Collins积分与Collins程函理论以及MATLAB软件工具,对腔镜失调前后激光陀螺中光束传输进行了仿真计算.结果表明,相同失调量的不同反射镜所产生的拍频频差是不同的,且分别从M1和M4镜探测到的拍信号频不相同|对于小增益激光器,使用球面镜的腔镜结构较平面镜的腔镜结构更易形成稳定光束空间位置分布|由所计算的空间坐标xn可以看出,双向行波光束的光斑中心发生了偏移,在一定的失调量下将会影响到激光陀螺的拍频输出.研究结果对激光陀螺的工程检测和腔镜调整有指导作用,有助于激光陀螺测量准确度的提高. 相似文献
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石英晶体温度效应对四频差动激光陀螺中光场偏振特性的影响 总被引:1,自引:0,他引:1
为研究石英晶体温度效应对四频差动激光陀螺的影响,从陀螺的自再现传播矩阵出发,结合石英晶体旋光率随温度变化的经验公式,利用琼斯矩阵求本征模的方法,得出了四频差动激光陀螺腔内光场本征偏振态与温度的关系并进行了数值分析,得到椭圆度和左右旋差损随温度变化的曲线。结果表明,石英晶体温度效应对偏振特性的影响与反射镜片的振幅反射率和反射相移有密切关系,对于典型陀螺参量,在-60℃~60℃范围内石英晶体温度效应导致左右旋差损从0增加至10-6量级, 椭圆度从0.122增至0.138。 相似文献
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实验观测了短腔染普激光器输出的多纵模激光及其经一级染料放大的激光光谱,比较了光谱特性。在一定情况下,短腔染料激光器的多纵模激光经放大器放大可产生一个至几个新纵模,新纵模与短腔染料激光器输出的纵模有相似的频率间隔、线宽及频率牵引等特征。新纵模产生属于三阶四光子混频(即四波混频)为主导的非线性光学效应。存在频率牵引表明,增益介质中的多波混频存在频率失配,在这一四波混凝中光子能量并不守恒。 相似文献
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四频差动激光陀螺中的S—P各向异性效应 总被引:7,自引:0,他引:7
理论分析了四频差动激光陀螺中左,右旋椭圆偏振模式的非对称性,这种非对称性激光陀螺性能的影响是至关重要的,而引起这种非对称性的物理因素是环形的S-P相位和损耗的各向异性。 相似文献
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Frequency tunable semiconductor laser has potential applications in resonator integrated optic gyro (RIOG) for its small size and easy to be integrated. An alternative construction of frequency tunable semiconductor laser with planar waveguide external cavity is proposed in this paper. The frequency tuning section, which is placed between the active section and Bragg grating section, is designed to be one part of the waveguide external cavity. The slab etched grating, based on the silicon-on-isolator ridge waveguide, is adopted to narrow the width of reflectivity spectrum. After the theoretical analysis and simulations, the frequency modulation coefficient of 2.1 MHz/mA is obtained, and the power change is less than 3.6 × 10−4 dB/1.6 GHz. The proposed configuration combines the advantages of wavelength tunable laser and external cavity laser, and it can realize precision frequency tuning, ignored power fluctuation and narrow linewidth, which contribute much to RIOG. 相似文献
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Wavelength tuning characteristics of a fabry-perot semiconductor laser with an external short cavity
Wavelength tuning characteristics of a Fabry-Perot semiconductor laser with an external short cavity are analyzed, in which
the oscillation wavelength can be changed by slightly altering the external cavity length. Analysis is based on rate equations
for an optical power and carrier density. It is shown that the wavelength tuning range is dominated by a change of carrier
density through the effect of carrier-induced refractive index change in the active layer of a laser diode. This depends on
effective coupling coefficients of the optical field iteratively reflected back to the laser diode by the external mirror,
and on reflection coefficients of an anti-reflection coated laser facet and the external mirror which compose the external
cavity. The effective coupling coefficient is also derived using the waveguide theory and Kirchhoff ’s theory. Finally, an
unstable condition which may limit a stable wavelength tuning range is shown by results of a linear stability analysis of
rate equations. 相似文献
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The optical feedback characteristics in a Zeeman-birefringence HeNe laser have been studied systematically when the external cavity varies in a large range. The intensity variations of the two orthogonally polarized lights are observed during the laser cavity tuning in the dual frequency laser. When the external cavity length is an integral multiple of the laser cavity length, either polarized light's intensity modulation depth varies not obviously when the laser works in dual modes conditions or single mode condition. But when the external cavity length is far away from an integral multiple of the laser cavity length and the laser works in different dual modes conditions, polarized light's intensity modulation depth varies obviously. This characteristic can guide us to tune the laser to work in single mode condition to improve the sensitivity of the optical system when the system is used for a large displacement measurement. It can also be used for measuring the position of the target mirror. The theoretical analysis is in good agreement with experimental results. 相似文献
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<正>Theoretical analysis and experimental research on the polarization properties of output light in gyro are carried out to investigate the phenomenon that the amplitude of an output voltage signal is modulated by dither bias in laser gyros consisting of totally reflecting prisms.Taking the effect of prism stress birefringence into account,an analytical formula of the output light intensity in the gyro and the relationship between the polarization parameter and the amplitude modulation of the output signal are obtained and discussed.For the first time,the polarized power value of the output light is adopted as a basis to estimate the output signal amplitude fading extent of laser gyros.Experimental results demonstrate that when the value of polarized power of output light is below 25.5%of that in ideal static case,the standard error is over 0.0337 dBm,and the displacement extent of the prism is higher than 53%of the radius of the beam waist in the gyro cavity,the amplitude modulation extent of gyro output signal can reach up to 16%,which badly influences the measurement accuracy of the laser gyro.Using this polarized power detecting measurement method can repair the gyro immediately during its fabrication process,improve the testing and production efficiency and shorten the product development cycle. 相似文献
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电光晶体调谐的外腔反馈半导体激光器 总被引:1,自引:0,他引:1
报道一种用电光晶体实现快速调谐和凋制激光频率的方法.在Littrow型外腔反馈半导体激光中插入LiNbO3晶体,利用LiNbO3晶体的电光效应,通过改变晶体电压来调节激光器的有效腔长,可以对激光频率进行快速的调谐和调制.采用该方法,自制外腔反馈半导体激光器的调谐频率可达到2 kHz,它的调谐范围为350 MHz,激光频率调谐系数约为1.06 MHz/V,用饱和吸收光谱观测频率调谐的效果.快速激光频率调制可以应用在稳频技术上,将外腔反馈半导体激光器调制在5~100 kHz频率下,均获得了87Rb原子D2线的饱和吸收光谱的色散信号,并实现了激光频率在饱和吸收峰上的长期稳定. 相似文献
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针对异面腔四频差动激光陀螺(DILAG)工作模式不确定性和跳模对其性能的负面影响,提出了根据开机时腔体温度快速选择最优初始模的智能选模方法。分析了纵模阶数对DILAG的零偏和比例因子的影响以及跳模的危害,指出选择最优初始模是在现有基础上进一步提高DILAG性能的重要方法。通过温度实验做出了最优模相应的压电换能器(PZT)驱动电压随温度的变化曲线,为建立选模模型提供了基本依据。实验表明,智能选模使腔长控制系统加电后能快速稳定在最优初始模,减小了跳模几率,提高了腔长控制电路的鲁棒性和自适应性,对改善DILAG的性能、可靠性具有实用价值。 相似文献