Powerful picosecond-pulsed laser radar with micrometer ranging resolution

This paper presents a high pulse repetition frequency (PRF) eye-safe laser radar for near-field ranging using novel high-power laser pulses with ultra-short pulse duration in the picosecond region from commercially available semiconductor lasers. The optical pulses have been attained by a new pumping current modulation principle based on an extremely fast and strong carrier injection into the active region of a gallium arsenide (GaAs) single heterostructure (SH) laser diode. For the first time a measurement uncertainty of less than 300 ¿m and a ranging resolution of 86.1 ¿m have been attained. High lateral resolution with a spot size of 1 mm has been obtained by small emitting areas. The pulsed laser radar has been combined with a beam deflection unit for three-dimensional (3D) object mapping. Experimental results on the system performance and object imaging will be presented. Further applications focussing on traffic control will be discussed.