  Good geometrical calibration is essential in the use of high resolution
detectors. The individual sensors in the detector have to be calibrated with an
accuracy better than the intrinsic resolution, which typically is of the order
of 10 um. We present an effective method to perform fine calibration of sensor
positions in a detector assembly consisting of a large number of pixel and
strip sensors. Up to six geometric parameters, three for location and three for
orientation, can be computed for each sensor on a basis of particle
trajectories traversing the detector system. The performance of the method is
demonstrated with both simulated tracks and tracks reconstructed from
experimental data. We also present a brief review of other alignment methods
reported in the literature.
