In some case,the axial distance from the sample to the lens is long in laser particle size measurement,so vignette appears because the lens aperture is limited,which reduces the measure precision and accuracy.
激光粒度测量中,当样品到透镜的轴向距离较大时,由于透镜口径有限,会因渐晕而降低测量的精度和准确度。
Simulation of the vignetting effect resulted from optical system in infrared image generation;
红外热像仿真中光学系统渐晕效应模拟研究
Due to the problem that the relative parameters of aviatic sensing image are often difficult to get,A line scan and data fitting method was presented in order to obtain whole gray change in image,and then to correct image vignetting phenomenon.
针对航空遥感影像在拍摄过程中相关参数不易获取的问题,提出了利用逐行扫描及数据拟合的方法来获取影像整体灰度变化情况,从而实现影像渐晕现象的复原。
Based on vignetting factor analysis,it is shown that the field of view are different in the energy non-dispersion plane and in energy dispersion plane,because of the different combination of aperture stop and vignetting stop.
通过对三重四极透镜成像系统的渐晕模拟,研究了并行电子能量损失谱仪中物方视场、漂移管径以及与电荷耦合探测器(CCD)幅面尺寸的对应关系,并由它们间的相互关系确定了与CCD幅面二维探测器尺寸相匹配的漂移管径。
Finally, an effect method to reduce the scanning vignetting is proposed.
本文用傅里叶光学理论,从成像系统脉冲响应函数的角度分析普通显微镜的成像特性,揭示共焦系统具有超分辨成像能力的原因,最后提出一种使扫描渐晕减小的有效方法。