A tracking fringe method for measuring the shape and position of a swimming fish

A novel tracking fringe projection method is developed to simultaneously measure variations in both the position and the shape of a moving object. The method combines a commonly used fringe pattern projection method and a laser tracking technique into one optical system. In this new system, two tracking fringes are used to track the object, while one fringe is used for reference fringe. The order of conventional fringes can be determined by measuring the angle of reference fringe. The method enables us to simultaneously measure the position and shape of a moving object, such as a swimming fish.