Although optical 3D topography measurement instruments are widespread, measured profiles suffer from systematic deviations occurring due to the wave characteristics of light. These deviations can be analyzed by numerical simulations. We present a 3D modeling of the image formation of confocal microscopes. For this, the light-surface interaction is simulated using two different rigorous methods, the finite element method and the rigorous coupled-wave analysis. The image formation in the confocal microscope is simulated using a Fourier optics approach. The model provides high accuracy and advantages with respect to the computational effort as a full 3D model is applied to 2D structures and the lateral scanning process of the confocal microscope is considered without repeating the time consuming rigorous simulation of the scattering process. The accuracy of the model is proved considering different deterministic surface structures, which usually cause strong systematic deviations in measurement results. Further, the influences of apodization and a finite pinhole size are demonstrated.

尽管光学 3D 地形测量仪器很普遍，但由于光的波动特性，测量的轮廓会出现系统偏差。这些偏差可以通过数值模拟进行分析。我们提出了共聚焦显微镜图像形成的 3D 建模。为此，使用两种不同的严格方法来模拟光表面相互作用，即有限元方法和严格耦合波分析。使用傅立叶光学方法模拟共焦显微镜中的图像形成。由于全 3D 模型应用于 2D 结构，并且考虑了共聚焦显微镜的横向扫描过程，而无需重复对散射过程进行耗时的严格模拟，因此该模型在计算工作方面提供了高精度和优势。考虑到不同的确定性表面结构，通常会导致测量结果的强烈系统偏差，证明了模型的准确性。此外，还演示了切趾和有限针孔尺寸的影响。