A single‐camera telecentric imaging stereo‐digital image correlation system and its application to carotid pulse signal detection

Abstract

AbstractCarotid pulse signal (CPS) is one of the most important biomarkers for evaluating cardiovascular risk. To realize easy‐to‐operate and accurate CPS detection, a single‐camera telecentric imaging stereo‐digital image correlation (stereo‐DIC) system is established. The system uses a specially designed colour separation device and a single colour camera attached with a telecentric lens to record images of blue and red colours from different optical paths. By processing the recorded two sub‐channel colour images using regular stereo‐DIC algorithm, full‐field 3D displacements of the skin on the neck directly over the carotid artery are obtained. The maximum fluctuations in the out‐of‐plane displacement direction are extracted as CPS, based on which velocity, acceleration and frequency can be further extracted. The performance of the established system was demonstrated by detecting the pulse signal of a volunteer before and after exercise.