太赫兹双轴共焦扫描显微成像轴向特性分析

Axial Character Analysis of Terahertz Dual-Axis Confocal Scanning Microscopic Imaging

太赫兹双轴共焦扫描显微成像系统能够提高反射式共焦扫描显微系统的分辨率，为保证成像系统性能，需要合理选择离轴抛面镜组的直径、焦距和入射角等参数。提出了一种2.52 THz双轴共焦扫描显微成像实验方案，仿真研究了主要系统参数对成像系统分辨率的影响，并在所确定的系统参数条件下，计算分析了探测器位置偏移对系统轴向特性的影响。结果表明，当探测器轴向偏移在-1.73～1.73 mm范围内时，光强不小于探测器正好位于焦点处时光强最大值的80%；当探测器横向偏移范围在-0.03～0.03 mm范围内时，分辨率基本不变，响应峰值的微小偏移可以忽略。

Dual-axis confocal scanning microscopic imaging can improve the resolution of reflection-mode confocal scanning microscopic imaging system. In order to ensure the good performance of the imaging system, the parameters of the off-axis parabolic mirrors must be rationally selected, such as diameter, focal length and incidence angle. A diagram of 2.52 THz dual-axis confocal scanning microscopic imaging is designed. The influence of the main parameters on system resolutions is simulated and studied. Then, with the application of definitive parameters, the influence of the deviation of detector on axial response character of the system is calculated and analyzed. When the axial deviation of detector in the range of -1.73~1.73 mm, the resolution barely changes and the light intensity received by detector is greater than or equal to 80% of maximum. When the transverse deviation in the range of -0.03~0.03 mm, the resolution barely changes and the slight deviation of response peak value can be ignored.