InGaAsP/InP Geiger-mode APD-based LiDAR

During the past decade, significant advancement has been made on InGaAsP/InP Geiger-mode APDs (GmAPDs) through improvements of material growth, device design and operating circuitry. With the increase in device performance and the growing maturity of device fabrication technology, high performance, large format InGaAsP/InP GmAPD arrays have been successfully designed and manufactured. These arrays have single photon sensitivity in the short wavelength infrared (SWIR) spectral band and can provide 3-D imagery. InGaAsP/InP GmAPD arrays provide an enabling technology for many active optical applications, such as 3-D light detection and ranging (LiDAR) and other photon-starved applications where single photon sensitivity in the SWIR band is critical. InGaAsP/InP-based Geigermode LiDAR has been extensively used on airborne platforms. By using optical wavelengths along with sub-ns laser pulse widths, 3-D Geiger-mode LiDAR techniques provide centimeter-scale range resolution over extremely long distances on the order of tens of kilometers. Through the use of high-performance single photon detectors, Geiger-mode LiDAR systems achieve an order of magnitude improvement in mapping rate over other competing LiDAR technologies. A more recent exciting application of InGaAsP/InP GmAPD-based LiDAR is to enable advanced driver assistance systems (ADAS) and vehicle autonomy on automotive platforms. The single-photon sensitivity of GmAPDs and greater eye-safety of diode lasers at wavelengths beyond 1400 nm provide disruptive automotive LiDAR performance that will be essential to future autonomous vehicle navigation. Single photon sensitivity and simple pixel circuit operation enable the reduction in overall system SWaP, while the scalability of these semiconductor devices enables dramatic reduction in LiDAR cost.