LUMENTUM’s multi-channel VCSEL arrays in combination with SPAD (Single photon avalanche photodiode) receivers can make up the primary components of a “true” Solid-State Electronic Scanning LIDAR. The light from VCSELs reflects off an object, and is detected by an SPAD array receiver, that contains depth information, allowing for line scanning and 3D imaging of surrounding objects. The current system has 1D addressability and can perform line scanning in a single direction. The novel optics design consisting of collimating lenses and a horizontal diffuser allows for pairing of VCSELs with SPAD arrays of different sizes and aspect ratios and illuminating different field of views. The VCSEL has 57 channels with 7J epi architecture, with each channel emitting up to 248W at pulsewidths of 5-6ns, DC of 0.03%, making them optimal for short to medium range LIDAR. Wafer level testing of VCSELs at pulsewidths of 100ns, shows very good uniformity in power, voltage, wavelength, divergence and near field uniformity, between different channels. The channel to channel leakage between the anode pads is negligible and in the order of nano-amperes. In this paper, we will focus on VCSEL part of the system and present wafer level test results and initial module data at high speed.
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