Correction of phase-delay distortion for α-β circular scanning.

Abstract

α-β circular scanning with a large scanning field of view and high reliability can be widely applied in laser scanning imaging systems and laser processing. However, mechanical inertia of the galvanometers introduces phase delay and ultimately leads to scanning distortions in α-β circular scanning in both constant angular velocity scanning (CAVS) and constant line velocity scanning (CLVS). To compensate for the phase-delay distortions, two correction models are respectively proposed for CAVS and CLVS, which utilize phase-frequency relationships based on the galvanometer's transfer function. Experimental results show that the presented models can effectively correct rotation distortion in CAVS and tortuosity distortion in CLVS. The correction of phase-delay distortion can improve the image quality and refine positioning accuracy in laser scanning systems.