In a light emission driving device (1), a high speed APC circuit (11) has a time constant τ1 to reach a target light intensity and a low speed APC circuit (13) has a time constant τ2 larger than the time constant τ1 to reach the target light intensity. A control unit (9) of the light emission driving device (1) uses the high speed APC circuit (11) at the time of startup of the light emission driving device (1), and when a predetermined time has passed after the light intensity of laser light has reached the target light intensity, switches to the low speed APC circuit (13) and supplies an initial signal causing the low speed APC circuit (13) to output a driving signal corresponding to the target light intensity.
