Improved transition detection algorithm for a self-mixing displacement sensor

An improved transition detection algorithm for a self-mixing interference (SMI) laser sensor is presented in this study. The proposed algorithm can correctly identify extreme points of SMI and can quickly and accurately locate determination thresholds, thus it can effectively reduce positioning deviation. The SMI laser sensor enables accurate reconstruction of the displacement information from a SMI signal. Displacement reconstructions performed by improved transition detection algorithm have been validated through simulations and experiments.