摘要
杂散光是影响显微系统成像质量的重要因素之一,在光学镜面加工及光学镜面清洁过程中会带来不同程度的镜面散射,这部分镜面散射所带来的杂散光影响不可忽视。以放大倍率为20×,数值孔径为0.49的显微物镜为基础,利用Trace Pro光学分析软件,建立了黑斑法测量显微物镜杂散光系数的仿真模型,对照明数值孔径、照明视场以及黑斑位置三个影响杂散光测量条件的因素进行仿真探究,验证了模型的可行性。在此基础上,研究了表面粗糙度(2、5、10、20 nm)和表面颗粒污染水平(230、500、750)对不同NA显微物镜杂散光的影响。仿真结果表明,表面粗糙度大于10 nm或表面洁净度大于500均会严重影响显微物镜像面杂散光的分布,降低显微物镜的成像质量,尤其对大NA显微物镜影响更为明显。因此,为控制镜面散射对显微系统性能的影响,应提高镜面加工工艺并保持镜面清洁。
Stray light is one of the important factors affecting the image quality of microscopy systems. During the processing of optical elements, stray light caused by specular scattering can not be ignored. Taking microscope objectives with 20x magnification and NA=0.49 as a typical example and using the optical analysis software TracePro, a simulation model of measuring veiling glare of microscope objectives is built up. Through analyzing the factors affecting the model with different illuminance numerical apertures, different illuminance fields and different black spot positions, the feasibility of the model is verified. On this basis, the stray light intensity on the image plane with different NA microscope objectives is simulated quantitatively under the condition of different surface roughness (2, 5, 10, 20 nm) and different cleanliness levels (250, 500, 750). The results indicate that the surface roughness greater than 10 nm and the cleanliness level higher than 500 will change the stray light intensity distribution on the image plane, and affect the system performance significantly, especially for those microscope objectives with large NA. It is of critical importance to keep the surface of optical elements clean and to improve the processing technology of optical elements.
出处
《激光与光电子学进展》
CSCD
北大核心
2015年第10期172-178,共7页
Laser & Optoelectronics Progress
基金
国家重大科研装备研制项目(ZDYZ2013-1)