Laser stripe sub-pixel peak detection in real-time 3D scanning using power modulation

Abstract

Laser stripe sub-pixel peak estimator algorithms depend on the light intensity readings around the peak and are susceptible to saturation and noise. Real-time 3D scanning prefers fast estimator algorithms based on simple and yet accurate stripe models. Modular test setup for 3D scanning is utilized to project a laser stripe on the target with patterned surface. Laser power modulation is used to generate series of captures with various stripe intensities. Stripe images are analyzed to find preferred modulation range suitable for estimator algorithms on both black and white surfaces. Empirical noise and laser stripe profile data are used to verify estimator algorithms assumptions. A novel algorithm for sub-pixel peak detection applicable to saturated laser line images is proposed.