back-emission electron radiography [`bak i`mish·ǝn i`lek´trän ´rād·ē`äg·rǝ·fē] ELECTRONICS A technique used in microradiography to visualize, among other things, the presence of material of different atomic numbers in the surface of the specimen being observed; the polished side of the specimen is facing and in close contact with the emulsion side of a fine-grain photographic plate; a light-tight cover holds the specimen and plate in place to be subjected to hardened x-rays. |