There are no bulbs, It is electroluminescence.
Electroluminescent (EL) devices are actually lamps. They emit light, but they are unlike any traditional lamp. Instead of creating light by heating a filament --- as in an incandescent light bulb --- or by charging a gas field --- as in a fluorescent or neon tube, EL relies on phosphorescent materials which glow when exposed to a small electrical current.
El lamps are cool, low power and emit a soft light without any irritating glare. They are invariably very thin, almost like ribbons or sheets of paper, and they can be produced in a variety of colors.
The source of light is a phosphorous mixture which is spread onto a transparent, conductive ITO film and then covered with another thin sheet of conductive material.
In most EL tape configurations, electrical power is usually provided through copper or aluminum foil conductors. In EL sheets, panels or other applications, different conductive materials can be used depending upon design requirements.
Terminals provide connections for electrical supply and can be located anywhere along the length of the copper or aluminum foil. In the custom pattern sheet, several dozen terminals are placed around the edge of the sheet to provide connections for customized applications.
Alternatively, electrical feed wires can be connected directly to the foils with adhesive tape, solder, screws or clamps. Care should be exercised when making connections to avoid electrical shock and short circuit hazards.
Specially designed power connectors can also be used to attach electrical feed wires to an EL tape.
Power is supplied through a small inverter. In the simplest application DC power is fed from an adaptor, plugged into a source of household current, to a single inverter. The inverter then converts the DC power to the appropriate level of AC power for an EL application. The brightness of a display can then be controlled by adjusting the frequency of the AC power.
Animated or flashing displays require a driver to operate. A driver is simply an inverter connected to an IC chip which is then connected to several different EL sheets, panels, tapes or decals. As different lamps are illuminated, they produce an animated effect.
Animated effects include flash or blinking where one or more lamps light up intermittently. When done in sequence, the human eye will detect movement in an image.
Other effects include stacking up or stacking down where an image incrementally becomes filled with light, or incrementally becomes dark.
