ANDREW LAMBERT PHOTOGRAPHY / SCIENCE PHOTO LIBRARY ANDREW LAMBERT PHOTOGRAPHY / SCIENCE PHOTO LIBRARY
Cathode ray tube. Image 1 of 2. Demonstration showing how a beam of electrons can be used to produce fluorescence on a phosphor-coated screen, as seen in television cathode ray tube (CRT) displays. Here, electricity from the wires (left) is heating a cathode to produce a beam (blue) of electrons (also called a cathode ray), which is seen by the ionisation of the gas around it. The phosphor-coated area (round, at right) is glowing green as the electrons cause the phosphor to emit light. In a CRT display, the beam is moved using magnetic fields. Here, Helmholtz coils (round) surround the glass tube, and will provide the magnetic field. Here, the Helmholtz coils are not switched on. See image T540/149 for this electron beam deflected by a magnetic field.
Model release not required. Property release not required.