A high-speed method and system for inspecting a stream of parts using at least one transparent traveling carrier of a conveyor subsystem are provided. The subsystem has a forward reach and a return reach. The method includes controllably receiving a stream of parts in rapid succession on the at least one traveling carrier and utilizing the subsystem to transfer the stream of parts in rapid succession to a part inspection station. The bottom surface of each part is illuminated through its traveling carrier with radiant energy when the part is located at the inspection station to generate reflected radiation signals which travel through its traveling carrier. A bottom image of each illuminated bottom surface is formed from the reflected radiation signals at an imaging location between the forward and return reaches at the inspection station. The bottom images are detected at the imaging location.