The Research About The Electrooptics Function Of DKDP Crystal As Q Switch

The laser has very extensive applications in medical sciences.The accurate control to pulse width ensures radically the contemporary laser's security in treatment.The ns-scale sustained pulse time attribute the success to the development of Q switch technology.It is for DKDP Crystal's lognitudinal electrooptics effect and half-wave voltage unchangeable that it can be used as Q switch. Based on the theory of DKDP crystal, the length of the crystal changing can not affect its function as Q switch. But in practical applications, when the length is smaller than a certain length, it can not be a wonderful Q switch. So, first we should find out the reason according to the electric field within the crystal, and then we compute the critical length. In later experiments, we will measure and observe whether the half-wave voltage, the proportion of extinction and the Awl-light interference change with the length of crystal changing? If change, what is the trends? At last, we will put the crystal with different lengths into the YAG Laser cavity to test if its Q switch function is normal and calculate the proportion between dynamic state and static state, and then we can find the length at which the crystal can not be as Q switch, contrast to the critical length and show the analyzing results.Based on these above, our group have made lots of efforts and obtained some certain progresses. The main content and results of this thesis are listed as follows: the Q switch's electrooptics function can be improved effectively by changing the electrode's location on DKDP Crystal.