Multiple Targets Identification in the Linear CCD Measurement System

Optical measurement based on three linear charge-coupled devices (CCD) has prominent advantages in precise coordinate measurement and dynamic position tracking. However, it is difficult for the linear CCD optical measurement system to distinguish multiple markers when they are illuminated simultaneously, which leads to a marker matching problem. This paper proposes a new marker correspondence scheme to distinguish three markers in the linear CCD system by using four pairs of linear CCDs and cylindrical lenses. The relationship of projection points on four linear CCDs of one marker is derived. The analysis of the constraint equation is given, and the most suitable projection points which come from the markers are matched. The numerical simulation is conducted to demonstrate the feasibility of the proposed method, and the result shows that this approach enables the linear CCD measurement system to identify the correspondence relationship of three markers, thus breaks through the limitation that the linear CCD measurement system can only track one marker at a time.