DEFLECTING SIGNAL GENERATING CIRCUIT

摘要

PURPOSE:To realize the variation of the scan line number with a high stability and high accuracy to the temperature change modulus by using the D-A converter possessing the steps more than the least common multiple of the desired scan line number to generate the saw-tooth wave in case the number of the line scan lines is varied. CONSTITUTION:D-A converter 24 possesses the steps more than the least common multiple NA of line scan line numbers Nl-Nm to be switched. And the signal generating means supplies the digital signals increasing every line scan line and in the unit of NA/Nl-NA/Nm(steps) into converter 24 to generate the saw-tooth waves. The signal generating means contains counter 21 to count the line scan line number and ROM23 to receive application of the parallel output of counter 21 as the address and then to read the digital data. As a result, the scan line number can be varied with a high stability and high accuracy to the temperature change modulus.