Illuminated keyboards - absolute operating safety in the dark!
Illumination of data input devices and components is unavoidable in poor visibility conditions.
But aesthetic requirements are also playing an increasingly important role. The areas of point-of-sales, exhibition and conference management, intelligent furniture or building technology are representative of this.
LED technology, combined with a sophisticated design, enables the realisation of illuminated membrane keyboards (operating foils) that are only slightly thicker than the widely used EL lighting.
A long service life, high brightness and the possibility of individual key control open up completely new areas of application for the membrane keypad.
The combination with resistive or capacitive touchscreens is also possible. In this way, touch operation can be supplemented with optically and haptically perceptible buttons.
If the front film is laminated over the entire surface of the display, there are neither dirty edges nor disadvantages with regard to the IP protection class.
|Electrical max. Limits||35V DC / 100mA / 1W|
|Contact contact resistance||10Ohm - 500Ohm|
|Insulation resistance||>100M Ohm at 100V|
|Dielectric strength||250V Rms (50 - 60 Hz / 1min.)|
Expected life of keys
|Flat keys >5mil
Tactile buttons > 1 mil
|Required compressive force||Flat keys = 57 - 284 gr. (2 - 10 oz)
Tactile keys = 170 - 397 gr. (6 - 14 oz)
|Switching height||Flat keys = 0.1 - 0.5mm
Tactile keys = 0.6 - 1.5mm
|Operating temperature||Flat/metal dome = -20°C to +80°C
Polyamide dome = -20°C to +55°C
|Storage temperature||Flat/metal dome = -40°C to +80°C
Polyamide dome = -40°C to +60°C
|Humidity||40°C at 90% rel. humidity for 240h|
|Shock||20 G (max.)
(10-200 Hz, MIL-STD-202, M204, Cond. B)