Ball Aerospace has signed an exclusive license agreement to be the sole manufacturer of the Geiger-mode avalanche photodiode (GmAPD) light detection and ranging (LIDAR) cameras for the defense and aerospace industries. The license was provided by Argo AI, which acquired the former manufacturer of the technology, Princeton Lightwave Inc. (PLI), in October 2017. Over the past 10 years PLI developed and advanced GmAPD detectors and cameras capable of detecting single photons. This detector sensitivity combined onto multi-pixel arrays enables high resolution LIDAR and communication systems, which are capable of extended range operation with significant savings to system size, weight, and power. Specific applications of this technology include target detection, acquisition, tracking, 3D mapping, intelligence, surveillance, and reconnaissance missions capable of direct and coherent detection. In this work, we review the current state of this technology focusing on the three options of Geiger-mode cameras that will be manufactured by Ball Aerospace. Moreover, we present details of expected camera and detector performance (e. g. Format, Photon Detection Efficiency, Dark Count Rate, Wavelength, Timing), review production, manufacturing capabilities, and update the community on future technology paths for anticipated customer needs. Ball Aerospace will manufacture and further develop Geiger-mode LIDAR camera technology as the premier merchant supplier of advanced, large-format, single photon sensitive camera products and systems.
Hybrid receivers that enable switching between direct and coherent detection provide many imaging functions beneficial to scientific and defense applications. A hybrid receiver system is presented wherein a single detector is switched between the Geiger-mode and linear amplification modes of operation. This system benefits from enhanced functionality and lower size, weight, power, cost, and complexity compared with dual receiver implementations. The hybrid receiver sensing modality is reconfigurable on-the-fly between single photon direct detection and amplitude/phase coherent detection. The reconfiguration is achieved by adjusting detector bias (electrically) and by simultaneously enabling or disabling the local oscillator (optically). This work describes these two sensing scenarios, discusses the operation of the receiver system and shows laboratory-scale imaging results for each mode of hybrid receiver operation.
We investigate tunneling injection quantum-dot (QD) lasers both theoretically and experimentally. Our laser structure consists of two tensile-strained quantum wells (QWs) coupled to a compressive-strained QD layer. The QWs serve as efficient carrier collectors and as a medium to inject electrons into the QDs by tunelling. Polarization-resolved amplified spontaneous emission (ASE) spectroscopy is used to extract the transverse-electric (TE) and transverse-magnetic (TM) polarized optical gain spectra at very low to near threshold injection currents. At a low bias current, the TE polarized ASE from the ground state of the QD layer is observed. At an intermediate current level, the coupling of the QW ground state to the QD excited state becomes important and an increase of the TM polarized emission from the tensile-strained QWs at a higher energy level becomes significant. Near threshold current, we observe TE gain narrowing due to the QD excited-state activation and the pinning of TM gain with subsequent TE lasing above threshold. We explain the physics of tunneling injection from the QWs into the QDs and how the
tunneling injection affects the polarization resolved optical gain spectra as the injection current level increases.
We report on the operational characteristics of hybrid proton implanted/selectively oxidized vertical-cavity surface-emitting lasers (VCSELs) in the 980 nm region. We investigate the output and spectral characteristics of different sized implant/oxide aperture VCSELs. Important operational variables such as current/voltage threshold, output power, efficiency and transverse operating wavelengths are extracted from experiments. A clear correlation is deduced between the sizes of implant and oxide apertures and the output power and lasing wavelength. Moreover, precise choice of implant/oxide dimensions yields a single transverse mode and high output power VCSEL. Finally, we simulate these different sized VCSELs with a vector optical solver (Illinois-VCSEL optical solver) based on a numerical mode-matching method developed by Seurin and Chuang. We successfully compare the experimental spectra with theoretical results and find very good agreement.