固态环形激光器可作为单频激光光源，同时也是一种具有发展前途的新型激光陀螺的核心部件, 是当今研究的热点之一。随着空间技术和国防科技对光学陀螺的需求不断增加，各国都在积极开展固态环形激光器应用于激光陀螺的研究。本论文是对固态脉冲环形激光器应用于激光陀螺的探索性研究，旨在解决其研究过程中，现阶段需要解决的两个问题：获取稳定的连续锁模，提高锁模的稳定性和利用偏频技术来克服闭锁。由于连续波激光陀螺的理论不能直接应用于脉冲激光陀螺，本文首先对用于激光陀螺的超短脉冲环形激光器的理论进行研究。基于锁模脉冲频率梳原理，并考虑了脉冲激光器的有限纵模线宽，对影响脉冲激光陀螺测量精度的因素进行了研究。其次，建立了广义激光陀螺闭锁阈值物理模型，该模型既适用于脉冲激光陀螺，也适用于传统的连续波激光陀螺。在被动锁模技术研究上，主要从被动锁模器件和谐振腔设计两个方面展开。首先，基于可饱和吸收体的吸收率对光强的依赖和多光束干涉理论，提出了利用非反谐振结构SESAM来获取皮秒级连续锁模激光脉冲的方法。理论和实验研究表明，采用非反谐振结构SESAM能实现稳定的连续锁模，与反谐振结构相比，非反谐振结构增加了SESAM宏观参数的设计自由度，减小了其生长难度。其次，利用传播变换圆方法设计了抗干扰性强的被动锁模谐振腔。与对干扰敏感的谐振腔相比，在我们设计的抗干扰性强的谐振腔中，由相同热透镜焦距起伏导致SESAM处光斑半径的相对变化幅度从40%降到3%以内，光轴方向相同的振动导致SESAM处光斑半径的相对变化幅度从35%降到2.5%以内。实验结果表明，当谐振腔对干扰敏感时，锁模会受干扰而经常中断；而利用我们设计的抗干扰性强谐振腔，能够实现不间断稳定连续锁模长达10个小时以上。利用法拉第旋光器和两个λ/4波片构成了偏频系统，对固态环形激光器的偏频进行了实验研究。计算表明，45o法拉第旋光器可使我们搭建的环形谐振腔产生约35MHz的频差，该频差远大于闭锁阈值。实验中发现，实现偏频后，该固态环形激光器中出现强烈的模式竞争，由原来的双向输出变成了单向输出。

Solid-state ring lasers can be used as single frequency light sources and a promising novel laser gyroscope, and it is becoming a current hot research subject. There is a growing need for new concepts in the design of optical gyroscopes due to the demands of space and national defense technology. In this thesis, the solid-state ring laser applied to optical gyroscope is exploringly investigated. We solve two urgent issues: (1) to obtain continuous wave mode-locked (CWML) laser pulses, and improve its’ stability, (2) to conquer the lock-in of gyroscope by using frequency biasing technique. In theory, the theory of the ultrashort pulsed ring laser applied to laser gyroscope is discussed. Based on the frequency comb theory, using a simple signal processing approach and taking into account the finite linewidth of each longitudinal mode in a mode-locked laser, we investigate the measurement accuracy of pulsed laser gyroscopes. We also build up the physical model of a generalized expression for the lock-in rotation rate of laser gyroscope, which can be applied to both conventional continuous wave and solid-state pulsed laser gyroscopes.With respect to passive mode-locking technology, we mainly study the the passive mode-locking devices and the resonant cavity design. (1) Based on the absorption of saturable absorber depending on the optical intensity and the interference theory, a method for obtaining continuous mode-locking picosecond pulse by the non-antiresonant semiconductor saturable absorber mirror (SESAM) is presented and relized. Results show that stable continuous-wave mode-locking can also be obtained in picosecond regime by the non-antiresonant SESAM. Comparing with the antiresonance structure, the design freedom of SESAMs macroscopic parameters is increased and the growth difficulty of the SESAMs is decreased. (2) A passive mode locking resonant cavity insensitive to external perturbation is designed using the transform circles theory. Results show that the the spot size at SESAM ranges caused by thermal focal length fluctuation, about 40% of their original in a sensitive resonator in which the two transform circles at SESAM intersect far from orthogonally. However, the spot size at SESAM ranges only about 3% for the case of the transform circles intersect nearly orthogonally, and less than 3% for the case of the transform circles intersect orthogonally. With regard to the optical axial direction vibration with the same amplitude 50μm, the spot size at SESAM ranges 35% when the two transform circles at SESAM intersect far from orthogonally, while it only ranges 2.5% when the two transform circles at SESAM intersect orthogonally. The experimental results show that when the resonator is insensitive to the external perturbation, the resonator can work at highly stable mode locking state and this state could continue for more than 10 hours. Otherwise the mode locking operation is very easy to be broken by interference.After realizing the stable continuous wave mode locking operation in ring lasers, we insert a frequency biased system consisting of a Faraday rotator and two λ/4 wave plates in a solid-state ring laser, and investigate the frequency bias of the mode-locked ultrashort pulsed ring laser. The numerical calculation shows that the Faraday nonreciprocal effect can generate 35MHz frequency difference between CW and CCW laser pulses in our ring lasers, when rotation angle is 45o for linearly polarized light. The generated frequency bias is larger than lock-in rotation rate in solid state pulsed lasers. The experimental results show that the severe mode competition appears in the solid-state ring laser and its’ work change from the bidirectional operation to the unidirectional operation with the realization of the frequency bias.