Detection and mapping of specular surfaces using multi bounce LiDAR returns

Connor Andrew Henley, Siddharth Somasundaram, Joseph Hollmann, Ramesh Raskar

Abstract:

We propose methods that use specular, multibounce LiDAR returns to detect and
map specular surfaces that might be invisible to conventional LiDAR systems that rely on direct,
single-scatterreturns. Wederiveexpressionsthatrelatethetime-andangle-of-arrivalofthese
multibounce returnsto scatteringpoints on the specular surface, and then use theseexpressions
toformulatetechniquesforretrievingspecularsurfacegeometrywhenthesceneisscannedby
a single beam or illuminated with a multi-beam flash. We also consider the special case of
transparent specular surfaces, for which surface reflections can be mixed together with light that
scattersoffof objectslying behindthe surface.