Phosphor lamp

Phosphor lamps were used for lighting. They made use of electron excitation, so when shook, the light grew brighter.

The human colony on Frontios used phosphor lamps as their primary light source as they had no electricity. Turlough claimed that the metal casing being used on the lamps made them a fire hazard. The Fifth Doctor had Turlough and Tegan return to the TARDIS to fetch a better light source as he was unable to work under the lamps dull glow.

When the Doctor and Norna were captured by Tractators, Tegan freed them by throwing a phosphor lamp among the, The explosion injured them and allowed the Doctor and Norna to escape. (DW: Frontios)