ROOF-MOUNTED OCCUPANT RESTRAINT SYSTEM

The present disclosure relates to a method for imaging an optical signal received by a graded index (GRIN) optical element to account for known variations in a graded index distribution of the GRIN optical element. The method may involve using a plurality of optical detector elements to receive optical rays received by the GRIN optical element at a plane, where the plane forms a part of the GRIN optical element or is downstream of the GRIN optical element relative to a direction of propagation of the optical rays. The optical rays are then traced to a plurality of additional specific locations on the plane based on the known variations in the graded index distribution of the GRIN optical element. A processor may be used to determine information on both an intensity and an angle of the received optical rays at each one of the plurality of specific locations on the plane of the GRIN optical element.