The resolution of optical system can not reach its diffraction limit because of the phase aberrations caused by atmospheric turbulence and other wavefront errors . adaptive optics technology uses deformable mirrors to perform dynamic phase modulation and endow optical system the ability to decrease the influence of dynamic wavefront errors 大气湍流等动态干扰使光波面相位发生畸变，使光学系统的分辨率无法达到其衍射极限，而自适应光学系统使用变形镜对光波面进行动态相位调制，赋予了光学系统能动可变的能力而有效地解决了动态干扰的问题。
In fact , hartmann - shack wavefront sensor is affected by the noise of ccd and the constructed error too . in our compare , a bridge is setup , which is the original wavefront composed by zernike polynomial , we transform the original wavefront into far field . then we can compare the accuracy of hartmann - shack wavefront sensor with the accuracy of the system of far field diagnosis in detecting the farfield , using diffraction limit and encircle energy 我们在进行两者相互比较的过程中，搭建了一个比较的桥梁，即由zernike多项式组成的各种原始像差波前，将它也变换到远场作为原始理想远场光斑，然后，以它的衍射极限和环围能量曲线作为评价标准，比较hartmann - shack波前传感器和远场测量系统在光束质量诊断中的探测精度。
At the same time , the possibility of using nonlinear optics in widening the detecting wave band of hartmann - shack wavefront sensor is exploringly discussed . adaptive optics guarantees the beam quality of laser projecting system . beam cleanup , atmospheric turbulence compensation and correction of any disturbance and fabrication error in the light way are required to promise a near diffraction beam , but normal adaptive optics system can only correction one of them 自适应光学进行光束大气传输波前畸变校正时，要求系统必须能进行光束净化和校正大气湍流造成的波前畸变，并且能够同时有效地克服发射系统制造误差、重力变形以及光路内部气体扰动的影响，得到接近衍射极限的输出激光光束。
The tuning curve of type - i phase matching of bbo opo are measured with accuracy ; the maximum conversation in total of the system is about 31 % at 615 . 6 nm , and it is fitted well with the gtp formula ; in the end we compared the output linewidth and unstable cavity far field beam qua lity of the bbo opo under the condition of type - i phase matching and type - ii phase matching , it is proved that we can obtain the parametric output of linewidth less than 0 . 3 nm and the beam divergence angle approaching diffraction limits by take the advantages of type - ii phase matching and unstable cavity designs 测量了该系统的转换效率最大为31 ，并能与理论公式极好地吻合，最后比较了在类相位匹配条件下和类相位匹配条件下的bbo - opo的输出线宽，以及非稳腔的远场光束质量，实验结果表明，利用类相位匹配以及非摘要稳腔设计可以获得线宽小于0 3nlm 、光束发散角接近衍射极限的参量光输出。
The design results and the performance evaluation of f - theta200 and f - theta500 are given in detail . the designed lenses are simple and compact and their cost are low . the focusing performances are within diffraction limit , the relative illuminations quite uniform and the distortion relative to the f - theta linear relation small 详细给出了f - theta200和f - theta500的像质评价和研制结果,所研制的f - theta镜头具有工作面积大、结构简单紧凑、加工成本较低、聚焦性能达到衍射极限、工作面上相对照度分布均匀、能量集中度高和畸变小等优点。
