Gas discharge tube displays according to the present invention control power
applied to the tubes using isolator/switches, which can be opto-isolators in combination
with triacs, FET's or other semiconductor switching devices or devices which can
form part of a switching circuit. Such displays can also use, if desired and if
appropriate, isolators which also act as the switch without other switching devices
or circuits to switch and otherwise control activation of the tubes on the secondary
side, or high voltage side, of the power source or sources feeding the tubes. They
may also use such switching devices or circuits which act as both the isolator
and the switch. The opto-isolators separate or isolate the low voltage control
circuitry from the high voltage tube power circuitry, in conjunction with a triac,
FET, thyristor or other device, preferably a semiconductor device, that is adapted
to withstand the power load yet accomplish the switching necessary to control activation
of the tube in real time. The switching devices are adapted to shunt power from
the tubes, bypass the tubes, or otherwise remove power from the tubes in order
to control illumination of the tubes in order to produce a dynamic display. The
isolators/switches are preferably controlled by a controller which is adapted to
receive instructions and content, either from a local or remote source, in order
to create and display content on the display.