Multi-frame range gating for lighting-invariant depth maps for in-motion applications and attenuating environments

Abstract

Range gated imaging systems utilize short light pulses and synchronized detector cycles to image objects that are contained within a distance range. Single-image range gating allows depth estimation for static scenes, but this technique is not well-suited for in-motion applications or attenuating environments. In various embodiments, a multi-frame range gating system uses a series of range gate frames that are produced within a brief timing window, whereby each range-gate frame illuminates a different lighting-invariant depth range within the field of view. Multi-frame range gate cycles of as little as three frames are sufficient to produce precise lighting-invariant depth information for each pixel in a sensor for in-motion applications. Lighting-invariant depth information is produced with multi-frame range gate cycles of as little as four frames for in-motion applications for attenuating environments like fog, rain, dust, smoke, smog, and underwater.