Translator Disclaimer
20 May 2013 Highly sensitive LIDAR with a thumb-sized sensor-head built using an optical fiber preamplifier (3)
Author Affiliations +
We have developed a LIDAR system with a sensor head which, although it includes a scanning mechanism, is less than 20 cc in size. The system is not only small, but is also highly sensitive. Our LIDAR system is based on time-of-flight measurements, and incorporates an optical fiber. The main feature of our system is the utilization of optical amplifiers for both the transmitter and the receiver, and the optical amplifiers enable us to exceed the detection limit set by thermal noise. In conventional LIDAR systems the detection limit is determined by the thermal noise, because the avalanche photo-diodes (APD) and trans-impedance amplifiers (TIA) that they use detect the received signals directly. In the case of our LIDAR system, the received signal is amplified by an optical fiber amplifier before reaching the photo diode and the TIA. Therefore, our LIDAR system boosts the signal level before the weak incoming signal is depleted by thermal noise. There are conditions under which the noise figure for the combination of an optical fiber amplifier and a photo diode is superior to the noise figure for an avalanche photo diode. We optimized the gains of the optical fiber amplifier and the TIA in our LIDAR system such that it would be capable of detecting a single photon. As a result, the detection limit of our system is determined by shot noise. We have previously demonstrated scanning up to a range of 80 m with this LIDAR system with a 2 mm diameter of receiving lens. We improved the optical amplifier and the peak output power of LIDAR was over 10KW. We redesigned the sensor-head and improved coupling efficiency. As a result, we succeeded in scanning over a range of 100 m. This small and highly sensitive measurement technology shows great potential for use in LIDAR.
© (2013) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Daisuke Inoue, Tadashi Ichikawa, Hiroyuki Matsubara, and Manabu Kagami "Highly sensitive LIDAR with a thumb-sized sensor-head built using an optical fiber preamplifier (3)", Proc. SPIE 8731, Laser Radar Technology and Applications XVIII, 87310Y (20 May 2013);

Back to Top