Chen Xiaodong, Ren Liqiang, Qiu Yuchen, Liu Hong
College of Precision Instrument & Opto-electronics Engineering, Tianjin University, Key Laboratory of Opto-electronics Information Technology, Ministry of Education, Tianjin, China.
Appl Opt. 2011 Oct 1;50(28):5524-33. doi: 10.1364/AO.50.005524.
This paper presents new formulas to determine the depth of field (DOF) of optical and digital microscope systems. Unlike the conventional DOF formula, the new methods consider the interplay of geometric and diffraction optics for infinite and finite optical microscopes and for corresponding digital microscope systems. It is shown that in addition to the well understood parameters such as numerical apertures, focal length, and light wavelength, system components such as aperture stops also affect the DOF. For the same objective lens, the DOF is inversely proportional to the size of the aperture stop, and it is proportional to the focal length of the ocular lens. It is also shown that under optimal viewing and operating conditions, the visual accommodation of human observers has no meaningful impact on DOF. The new formulas reported are useful for accurately calculating the DOF of microscopes.
本文提出了用于确定光学显微镜系统和数字显微镜系统景深（DOF）的新公式。与传统的景深公式不同，新方法考虑了无限远和有限远光学显微镜以及相应数字显微镜系统中几何光学和衍射光学的相互作用。结果表明，除了数值孔径、焦距和光波长等广为人知的参数外，孔径光阑等系统组件也会影响景深。对于相同的物镜，景深与孔径光阑的大小成反比，与目镜的焦距成正比。研究还表明，在最佳观察和操作条件下，人类观察者的视觉调节对景深没有显著影响。所报道的新公式有助于准确计算显微镜的景深。
