高分辨率4f传像系统分辨率的影响因素分析

研究了在实际应用中4f传像系统分辨率的影响因素及其作用机制,用于指导系统的设计和装调。首先,在理论上分析了由装调误差引起的像差对系统光学传递函数(MTF)产生的影响,并建立了描述二者关系的数学模型。基于该模型研究了1μm分辨率4f光学系统的装调误差,仿真计算了系统含有透镜偏心、倾斜、位移误差对MTF的影响,得到了分辨率随误差的变化曲线。实验结果表明,倾斜在15″以内,偏心误差在0.02mm,位移在0.01mm范围内,装调误差均会导致分辨率下降,虽然倾斜在极小范围内微调时分辨率会提高,但总的变化趋势不变。绘制的装调误差与分辨率的关系图,可为高分辨率4f系统的误差预估提供参考。

Analysis of influence factors of resolution in high-resolution 4f imaging system

The factors and its mechanism which influence 4f imaging systemic resolution in practice were studied to guide the design and adjustment of the system. Firstly, the influence of the aberration caused by adjustment error on the system optical transfer function (MTF) in theory, whereby the mathematic model for describing the relationship of them was established. Based on the model, the adjustment error of 4f optical imaging system of 1 μm resolution was derived, and the influence of lens eccentricity, incline and displacement on the MTF was simulated, thus the variations of the resolution with the errors were achieved. The result indicates that within the incline of 15", the eccentricity error is 0.02 mm and the displacement is within 0.01 mm. The adjustment error results in the decline of the resolution. Although the resolution increases while the incline within a minimum scope, the total trend will not change. The relationship figure of adjustment error and resolution can provide the reference for the error estimation of high-resolution 4f imaging system.