es de ru en pl fr it

Electroluminescent lamps (EL lamps)
Illuminated and backlit membrane keyboards.

An electroluminescent lamp (EL) is a thin-layered, electric system, usually a foil, that emits light with its entire surface under the influence of an applied voltage. EL lamps are used in various branches of the electronics industry, especially in liquid-crystal displays (LCD).
EL lamps are widely used in the membrane keyboards manufactured by our company. As they are integrated into the keyboard, a complete air-tightness of the system is preserved.

Lamp brightness (lifetime)
studies conducted by Du Pont in 1999

The illumination occurs when alternating voltages between 60 – 150 V and frequencies between 50 – 1000 Hz are applied. The usual voltage and frequency used in EL lamps are 130 V and 400 Hz. At these parameters, the average life expectancy of an EL lamp is ca. 5000 h after which the lamp brightness is believed to fall by 50%. If the value of either voltage or frequency is reduced, the current strength that is passed through the lamp decreases, and life expectancy of a lamp increases.
The colour of the illumination of an EL lamp depends on the type of ink used. It can be white, blue-green and yellow-green. Filters applied on the lamp surface can to some extent modify the shade of the illumination.

EL lamp brightness (voltage 115V, 400Hz)

studies conducted by Du Pont in 1999

Illuminated membrane keyboard - example