Sun-Kraft type A1 sunlamp
CONTACTLESS-GLOW-DISCHARGE
A special kind of glow discharge could be found in
sun-lamps from Sun-Kraft. This company used
mercury vapour glow discharge tubes without
electrodes like those of the Sun-Kraft type A1
sunlamp on display here. The ionisation of the
mercury vapour was obtained by placing the tube in
an electric field, generated by a high frequency
oscillator, a concept already demonstrated in 1893
by Nikola Tesla (1856-1943). Due to the lack of
electrodes the lifetime of these tubes was virtually
unlimited as long as they were not damaged
mechanically.
