Accurate rangefinder with laser pattern shifting

In this paper, a high accuracy, high density and high speed range finding method is described. The space encoding rangefinder has error on space sampling in principle. To improve this error, we introduce pattern shifting into laser scanning rangefinder. With this method, we can detect the projected pattern edge accurately, by taking advantage of the charge storing characteristics of a CCD device. Using this method we can obtain range images more accurate than normal space encoding with little increase in the measurement time. We can control the quantity of error with changing the angle of pattern shift. The realization of this method using the laser rangefinder and the simulated results in the computer are also described