Axial character analysis of terahertz dual-axis confocal scanning microscopic imaging

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.