Research On Double Corner Cube Ring Cavity And Its Application In Pulsed Injection-locking Laser

Wind shear,especially cloudless wind shear,is an extreme weather phenomenon of disordered wind,which seriously threatens the take-off and landing safety of aircraft.Long distance coherent Doppler wind lidars(CDWLs)is the only and effective method to measure wind shear in the cloudless sky.It is an important equipment for the take-off and landing safety of aircraft.At present,pulsed injection-locking laser is the major laser transmitter of CDWLs,and its stability and reliability are the direct challenges to engineered and commercial CDWLs.In this thesis,a double corner cube retroreflector(DCCR)ring cavity is investigated.In comparison with a traditional ring cavity,the DCCR ring cavity exhibits two important properties: anti-misalignment property and tunable output coupling.Therefore,if it is applied to the pulsed injection locking laser,the reliability of the pulsed injection locking laser can be greatly improved.In this way,the pulsed injection locking laser based on the DCCR ring cavity will be an excellent laser transmitter for CDWLs.The contents of this thesis are as follows:In this thesis,the anti-misalignment property of DCCR ring cavity was analyzed firstly.Three basic geometric properties of a corner cube retroreflector(CCR)were deduced theoretically.On the basis of these three geometric properties,the anti-misalignment capability of a single CCR and its influencing factors were calculated and analyzed,and the conclusion is that the smaller height-radius ratio and the larger refractive index of a CCR,the stronger anti-misalignment capability of the CCR is.The minimum available refractive index of a usable cone is 1.22.According to the anti-misalignment theory of the single CCR,a theoretical model of DCCR ring cavity anti-misalignment property was established.Based on this theoretical model,the relationship between the CCR alignment deviation,the CCR inclination and the anti-misalignment capability of the DCCR ring cavity was studied,and the factors affecting the DCCR ring cavity anti-misalignment capability were analyzed.It were concluded that the longer cavity length,the stronger the DCCR ring cavity anti-misalignment capability.Experimental results were consistent with anti-misalignment theory,and the anti-misalignment performance of CCR tilted 19° or shifted 0.8 mm in the DCCR ring cavity was realized.Secondly,the polarization characteristics of oscillating light in the DCCR ring cavity laser was studied.Based on the Jones matrix method,a theoretical model of oscillation light polarization state internal DCCR ring cavity was established,and numerical results were obtained.According to this theoretical model,a DCCR ring cavity with two polarized beam splitters(PBS)as output couplers was built up.Its output coupling ratio could be tuned by rotating λ/2 wave plate,rotating λ/4 wave plate and rotating CCR,the tuning range can reach 0.01%-97.53%.In addition,a stable cavity is designed by using ABCD optical matrix method,and a continuous-wave,output coupling tunable DCCR ring cavity laser was realized by employing a0.5at.%Er:YAG crystal.Finally,the application of DCCR ring cavity in pulse injection locked laser is studied.The seed laser beam transformation from seed laser to salve laser and cavity length adjustment configuration(double optical wedges)were designed,and the feasibility of seed laser injecting into DCCR ring cavity and resonance signal generating in the DCCR ring cavity were proved.Furthermore,by employing a Er:YAG non-planar ring cavity(NPRO)seed laser,the injection locking experiment based on the slave DCCR ring cavity was realized.Through tuning output coupling ratio of the DCCR ring cavity,the optimum operation efficiency of single frequency pulse laser at different pump powers was achieved.