Could Old Tube CCTV Cameras Be Disabled by Impact, Explosion?
Vidicon CCTV camera, image by randacnam7321.
Yes, apparently the old Vidicon tube cameras commonly installed in banks prior to the development of metal–oxide–semiconductor field-effect transistor (CCD) cameras could be disabled by impacts – including being hit by a shoe.
Video camera tubes used a cathode ray (electrons moving through a vacuum) tube in which a cathode ray was scanned across an image of the scene and the resultant current varied depending on the brightness of the target image on the target. Because the size of the striking ray was tiny compared to the target, the system delivered 576 lines in PAL.
The optical system of the tube camera’s image dissector focused an image onto a photocathode mounted inside a high vacuum. As light struck the photocathode, electrons were emitted in proportion to the intensity of the light reflecting from the scene. The entire electron image is deflected horizontally and vertically periodically so the image is scanned multiple times per second and a scanning aperture permits only those electrons emanating from a very small area of the photocathode to be captured by the detector at any given time.
Taken as a whole, CRT was a robust and long-lived technology, though it wasted most its current draw and CRT monitors are highly toxic (lead coated glass) and hard to recycle into anything other than more CRT monitors.
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