Electroluminescent backlight

Keytouch designs and manufactures front panels, membrane switches, and electro mechanical operating panels with embedded electroluminescent backlight (EL-film).

Advantages of electroluminescent backlight:

  • Low thickness
  • Light is distributed 100% evenly over large surfaces
  • No heat dissipation
  • Light weight
  • Flexible
  • Available in White and Green
  • Dimming available
  • Luminary buttons, texts, frames, logos etc.

EL-film structure

EL-film is printed in layers onto a polyester surface composed of a layer of custom-made phosphorous situated between two electrodes. When AC-voltage is connected, an electric field is created which ignites the phosphorous particles. Operation life of the EL-film depends on on-time and inverter voltage/frequency. Optimal duration is best obtained by dimming the light, installing a light sensor to switch it off when not needed, or by time-limited activation.

Since 1997, the production process related to EL-film has undergone constant evolution. Our expertise on the area currently includes technical printing processes, chemical processes, graphic design and electronic solutions.

Inverter

Keytouch can provide an inverter to the el-film, which can also control dimming of 0-100%. The inverter circuit has integrated filter components, which makes the el-film solution pass both Maritime and Military EMC requirements.

Screening

A shield layer can be embedded in the EL-film construction, to prevent crosstalk from the EL-film to nearby pushbuttons.

Technical Data

Power consumption

~0.15

mA/cm2 @ 5V

Dimming

 0-100%

Luminous intensity

20-25

Lux@100%

Serial reproducibility

15%

±

Wear life, 20°C / 50% RH

> 50.000

Hours

Thickness

>= 0.175

mm

Storage temperature at 30% RH

-40 – +100

°C

Application temperature at 30% RH

-40 – +85

°C

Data sheet EL-film