Semiconductor laser drive device for driving semiconductor laser element to achieve high output power, high-speed driving, and low power consumption

A distance measurement apparatus comprising:

• a semiconductor laser element;
• a semiconductor laser drive device for driving the semiconductor laser element;
• a photodetector element configured to obtain a quantity of reflected light indicating a quantity of light generated by the semiconductor laser element and reflected by a target object;
• and
• a processing circuit configured to calculate a distance to the target object based on the quantity of reflected light,
• wherein the semiconductor laser drive device comprises:
• a driver circuit connected in series to the semiconductor laser element, the driver circuit having a first terminal to which a bias voltage is applied, the driver circuit being configured to limit a current flowing through the semiconductor laser element so as not to exceed an upper limit corresponding to a magnitude of the bias voltage;
• a switching circuit connected in series to the semiconductor laser element and the driver circuit, the switching circuit having a second terminal to which a first pulse signal is applied, the switching circuit being repeatedly turned on and off according to the first pulse signal;
• and
• a compensation circuit configured to compensate for variations in voltage potential at the first terminal based on the first pulse signal, the variations occurring when the switching circuit is turned on and off.