An intake system for a vehicle engine includes an air cleaner and a plurality of throttle bodies. The layer of light responsive material includes a material that has a triplet exciton state which can be excited by incident electromagnetic radiation to provide collectable free charged particles at one of the first and second electrodes. The upper pavilion facets lie at an angle of between 45 and 80 relative to the girdle plane. Upon the occurrence of a trigger condition, storage stops and a trace is preserved.