In order to reduce the influence of anisoplanatism on the performance of telescope imaging system, and expand the effective Field-of-view (FOV) of system, anisoplanatic effect in wide-field-of-view telescope imaging system is studied here. First, a numerical simulation of anisoplanatic imaging through volume atmospheric turbulence by using multiple random phase screens has been developed. Then, the mean-square wave front errors of two separate object points between the on-axis position and the off-axis position with angle 0 are calculated based on the numerical simulation system under the typical atmospheric condition(atmospheric coherent length r0 = 0.1 m). The results show that when tilt errors have been included in the aberrated wave front, anisoplanatic effect becomes weaker as the diameter D of the imaging system increases, and the ascending variation of the mean-square wave front errors is less severe. Whereas, when tilt errors have been excluded, anisoplanatic effect becomes greater as the D increases, and the ascending variation of these is more severe. The larger the diameter of system aperture is, the weaker tilt anisoplanatism is. For large-aperture telescope imaging system, like D≥5 m, high-order wave front errors are the crucial influence.%为了减少非等晕性对望远成像系统性能的影响,扩大系统的有效视场,对宽视场望远成像系统的非等晕性进行了研究.首先采用多层相位屏法实现了非等晕成像的数值模拟,然后利用数值模拟系统计算了典型大气条件下(大气相干长度t0=0.1 m)轴中心点与偏离轴θ角度目标点两者间的畸变波前均方差值,分析了系统口径D分别为1m、2m和4m对应畸变波前均方差值随偏离角度θ的变化情况.分析结果表明,畸变波前有倾斜项时,系统口径D越大,畸变波前均方差值随角度θ的增加上升得越慢,非等晕性的影响越小；去掉倾斜畸变时,系统口径D越大,畸变波前均方差值随角度θ的增加上升得越快,非等晕性的影响越严重.倾斜非等晕性随系统口径的增加而减少,对大口径的望远成像系统(D≥5 m)主要考虑高阶波前畸变对成像的影响.
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