To draw a high quality image in which fluctuations are not conspicuous or are difficult to be conspicuous to human eyes while securing the degree of freedom of line period setting.

A spread spectrum clock generating device has a phase comparator 24-2 for detecting a phase difference between a reference clock 24-0 and a feedback clock 24-7, and a voltage control transmitter 24-4 for generating a spread spectrum clock of a frequency corresponding to voltage to be generated on the basis of a phase difference signal detected by the phase comparator 24-2. The spread spectrum clock generating device includes an analog modulated signal generating part 26 for creating an analog modulated signal 24-6 for changing a frequency modulation period of a voltage control oscillator 24-4 on the basis of a drive clock generated from the spread spectrum clock 24-7 output from the voltage control oscillator 24-4, and applying the analog modulated signal to the voltage control oscillator 24-4.