In the CDT(Color Display Tube) inspection, the multi-point convergence measurement process is essential and the widely used method of using 1-dim. CCD camera is known to take much efforts in handling and also take time to measure errors. As a remedy, it is proposed to use a set of photo sensors. The convergence error measurement using photo sensors shows that the system is less sensitive to sensor position, CDT size, and video signal frequency.
In this thesis, we have developed an algorithm for measurement of convergence error by using the second harmonic in the case of the change of convergence error, have implemented a measurement system based on DSP hardware.
