Vidicons

Vidicons are a family of vacuum-tube imaging sensors used in television cameras. They employ a photoconductive target and an electron beam that scans the target to reconstruct an image. Light incident on the target changes its conductivity, creating a charge pattern that modulates the electron beam current as it is swept by the raster. The resulting signal is amplified to form a video output. Vidicons are known for relatively simple construction, ruggedness, and good low-light sensitivity for their era, but they exhibit image lag, limited dynamic range, and susceptibility to flare and smear compared with later solid-state sensors.

Development and use: The vidicon concept was introduced in the mid-20th century and became widely used in broadcast cameras during the 1960s through the 1980s. They were produced by several manufacturers and came in monochrome and color versions; color systems often used multiple vidicon tubes or external color separation optics. Because of their vacuum-tube nature, they required high-voltage supplies and careful maintenance.

Decline and legacy: The advent of charge-coupled devices in the 1980s and 1990s led to rapid replacement of vidicon-based cameras in new equipment, though some specialist and vintage systems retained vidicon tubes for archival or aesthetic reasons. The vidicon family contributed to the development of modern image sensors and helped enable portable broadcast cameras in the early video era.