imaging tube

An image tube is an electron tube that converts incident electromagnetic radiation, such as light or infrared, into a visible image on its fluorescent screen. This technology was first used in 1936 and is also known as an image converter.1

In television technology, early cameras used mechanical spinning disks to scan a scene and convert light into electrical signals. By the mid-20th century, these were replaced by vacuum tubes that used an electron beam to scan an image focused on a light-sensitive surface within the tube. These electronic camera tubes, such as the Iconoscope, Image Dissector, Orthicon, Image Orthicon, and Vidicon, were crucial for the success of television. The Vidicon tube, for example, uses a photoresistive material whose electrical resistance changes with light intensity. An electron beam scans this material, and the resulting electrical signal is derived from changes in potential.2

While image tubes were foundational, modern cameras primarily use solid-state imagers like charge-coupled devices. However, the principles of image conversion and scanning developed with these tubes continue to influence imaging technologies.2