1. A method of inspecting thin objects with x-rays, which objects are thin enough in relation to a conveyor belt used in a system wherein both the object and belt are illuminated with x-rays so that when said belt and object are illuminated, the conveyor belt generates a much larger backscatter signal than the object, comprising the steps of, providing a belt conveying means having first and second belt portions which are separated by a gap, placing said thin objects to be inspected on said belt conveying means for transportion over said gap, providing a source of x-rays, directing the x-rays which are emitted by said source through the gap in the belt conveying means to illuminate said thin objects when they are over said gap, detecting radiation which is backscattered by said thin objects, and displaying an image corresponding to the detected radiation.