Pulsed laser diode can be used to measure distance in many applications

Available now from Mouser stock, Osram Opto Semiconductors' SPLPL90-3 Nanostack pulsed laser diode is operated by directly applying the forward current pulses to the anode and cathode pins. The device is suitable for a wide range of applications including hand-held laser range finders for golfers, hunters and civil engineers). Automotive applications include adaptive cruise control (ACC), pre-crash detection, collision avoidance and adaptive rear lighting. Traffic surveillance usages span laser speed guns, traffic recording and vehicle classification to distance measurement and fog detection. Other areas include professional laser sensors for distance measuring, positioning and protection applications. The cathode pin is the short one. To generate short (up to 100ns) and high-current (up to 75A) pulses a suited laser diode driver is necessary. The pulsed laser driver circuit consists of a capacitor with capacitance C and a switch which discharges the charge of the capacitors to the laser. The charging of the capacitor is done between two laser pulses. As switch a MOSFET or an avalanche transistor can be used.