Patent ID: 8194113

Claim:
A pulse-modulation-signal generating device that generates a pulse modulation signal for driving a light source to emit a pulsed light according to input image data, the pulse-modulation-signal generating device comprising: a high-frequency clock generating circuit that generates a plurality of high-frequency clock signals having different phases; a modulation-signal generating circuit that generates the pulse modulation signal based on transition timing data including timing data pertaining to a turn-on timing at which a state of the light source is changed from a turn-off state to a turn-on state and a turn-off timing at which the state of the light source is changed from the turn-on state to the turn-off state by inputting any one of the high-frequency clock signals for a predetermined period including the turn-on timing and the turn-off timing; and a phase-data generating circuit that generates pulse phase data including position data pertaining to a rise position and a fall position of a pulse signal based on the transition timing data; and a mask-signal generating circuit that generates a mask signal for inputting the any one of the high-frequency clock signals for the predetermined period based on the position data.