Design of three-dimensional structured-light sensory systems for microscale measurements

摘要

Recent advances in precision manufacturing have generated an increasing demand for accurate microscale three-dimensional metrology approaches. Structured light (SL) sensory systems can be used to successfully measure objects in the microscale. However, there are two main challenges in designing SL systems to measure complex microscale objects: (1) the limited measurement volume defined by the system triangulation and microscope optics and (2) the increased random noise in the measurements introduced by the microscope magnification of the noise from the fringe patterns. In a paper, a methodology is proposed for the design of SL systems using image focus fusion for microscale applications, maximizing the measurement volume and minimizing measurement noise for a given set of hardware components. An empirical calibration procedure that relies on a global model for the entire measurement volume to reduce measurement errors is also proposed. Experiments conducted with a variety of microscale objects validate the effectiveness of the proposed design methodology.