难以说明的

Based on the laser longitudinal mode splitting theory, a novel scheme of dual-frequency laser with large frequency-difference is presented using electrically controlled birefringence of liquid crystal, and the transmitted resonant mode splitting by birefringent of Fabry-Perot etalon has been analyzed theoretically. A new element of liquid crystal Fabry-Perot etalon is designed and fabricated, which serves as aselector and splitter of both laser longitudinal modes and Fabry-Perot etalons transmitted resonant modes. Two different experimental systems of laser-diode end-pumped Nd:YAG laser have been set up using two different LDs, and the transmission of liquid-crystal cell have been measured. When the empty LCFP is inserted in the cavity of high-power LD pumped Nd:YAG laser, the oscillation of a single laser longitudinal mode have been observed, such a result shows that the designed and fabricated LCFP element is capable of selecting single axial mode. While an anti-reflected liquid crystal cell is inserted in the cavity of Nd:YAG laser end-pumped by the high-power LD, it is difficult to confirm weather the laser longitudinal modes have been spitted or not. The subject is summarized in this thesis and the improvement of the project has been presented.

论文以激光纵模的分裂理论为基础，提出了可望获得几十GHz甚至上百GHz的液晶电控双折射双频Nd：YAG激光器的总体方案，并对用双折射效应分裂F-P标准具透射谐振模进行了理论分析；设计并加工了一种集激光纵模选择、激光纵模分裂和F-P标准具谐振透射模分裂于一体的多功能元件——液晶电控双折射F-P标准具；建立了两种不同功率激光二极管端面泵浦的Nd：YAG激光实验系统，并对液晶盒的透射性质进行了测试；将未灌注液晶的空液晶F-P摘要标准具插入大功率LD泵浦Nd：、叭G激光谐振腔内，观察到了单纵模激光输出，说明所设计和加工的液晶F一P标准具具有纵模选择能力；将镀有增透膜的液晶盒插入大功率LD泵浦Nd八7AG激光谐振腔内，是否产生了激光纵模分裂现象还难以确定。

The molecular motion of amorphous region at high-frequency was found to be hardly affected during the stretching processes. In summary, elongation has created major but different influences on the morphology and molecular motion of the aforementioned four series of polymeric elastomers. For those elastomers like natural rubber and poly , elongation has induced crystallization of the noncrystalline or the soft segments. The crytallinitiy and the crystal thicknesses increase monotonously during the course of the stretching; On the other hand, the stretching processes for those semicrytalline copolymers like EMA and POE are rather complex, including the formation of crystal at relatively low λand the destruction of the crystal at the utmost λ. It revealed that stretching process has resulted in a decreasing of the thicknesses and a shortening of 〓C T〓s for the orthorhombic crystalline components.

拉伸对上述四个弹性体体系的聚集态结构都产生了很大影响，但是影响的程度和内容因体系而不同，对于本身存在着化学交联或者是物理交联的体系而言，拉伸导致了其中本来难以结晶组分的结晶，且结晶度随着拉伸比增加而增加，与此同时，体系结晶的晶片厚度也会逐渐增加；而对于结晶性共聚物体系，如EMA和POE，结晶区本来起到了物理交联的作用，在这种情况下拉伸的影响变得比较复杂，拉伸对于不同晶型的影响有所不同，在拉伸比较低的情况下体系总体的结晶度会有所增加，说明有新的结晶产生，当接近或达到断裂伸长比时，体系的结晶度会突然降低，含量占优的结晶会被拉伸所破坏，含量较低的结晶在整个拉伸过程中受的影响较小。

Plunder melds and run with this jewel!

掠夺melds和运行与此宝石！

My dream is to be a crazy growing tree and extend at the edge between the city and the forest.

此刻，也许正是在通往天国的路上，我体验着这白色的晕旋。