We developed a method to obtain 3D shape
of object surface from the polarization state of
reflected/transmitted light at transparent objects by
solving the inverse problem of polarization raytracing.
We set the object into the middle of plastic
white sphere, and illuminate the sphere from 36
directions with incandescent lamps. There is a hole on
top of the sphere, and we observed the object from the
hole by polarizer-mounted gray CCD camera. We calculate
the polarization data from 3 or more images taken by
rotating the polarizer each for different angles. We
obtain the polarization data from these images. We
compute the polarization data by polarization raytracing
by giving an arbitrary 3D shape as an initial value. We
deform the 3D shape so that the difference between the
calculated polarization data and the obtained
polarization data will be small. We finally obtain the
surface shape of transparent objects by deforming the 3D
shape until the difference will be minimum. |
