Dark Non-Uniformity Correction and Characterization of a 3D Flash LIDAR Camera

摘要

A partial calibration technique for a 128 × 128 pin diode 3D flash LIDAR camera is presented. This paper presents dark non-uniformity correction (NUC) of a 3D flash LIDAR camera using dark frame subtraction. Dark frames are taken near threshold for intensity return to generate simultaneous trigger on a flash LIDAR camera, with trigger ramp set to zero for both range and intensity returns. Frames are cropped to a region of interest (ROI) and concatenated ideal dark intensity and dark range return into dark frames, processed into calibration files with nearest neighbor correction in dark intensity frames to correct out slowly varying, high intensity temporal noise when operating near threshold. Results and validation of applied NUC on 3D flash LIDAR camera are presented. We characterize a 3D flash LIDAR camera with PIN diode architecture including range walk, gain characterization in both intensity and range domains. Characterization of 3D flash LIDAR imager was performed using a fiber laser operating at 1550 nm, 20 μJ energy per pulse, TTL triggering, a pulse generator to generate time delay necessary for triggering the laser from the camera ARM signal, and an attenuator for fine control of the output signal. Time delay is relative to the range domain, whereas output signal is relative to the intensity domain.