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For more than 30 years, LED have been used in various industrial applications from switch cabinets to measuring instruments, in consumer products such as HiFi- equipment, telephones or personal computers, in traffic signal installations for road and railway or in indoor and outdoor automotive lighting.

In the last few years the efficacy of colored LED increased up to amazing 100 lm/W and more depending on the color and driving conditions. A trend which will proceed in the future.

As today's white LED can reach efficacies of more than 100 lm/W (efficacy depends on color temperature, color rendering and driving conditions)- they are more and more used in general lighting. In emergency lighting as well as decorative lighting, they arealready established in implementation area. Today, also applications such as illuminated advertising benefit from the advantages of LED, particularly by using colored LED-modules

Basic principles of LED (Light Emitting Diodes)

A light-emitting diode (LED) is a semiconductor diode that emits incoherent narrow-spectrum lightwhen electrical current is applied in the forward direction.

An LED consists of several layers of semiconducting material

When an LED is operated with DC current, light is generated in the active layer

The generated light is radiated directly or by reflections

In contrast to incandescent lamps, which emit a continuous spectrum, an LED emits light in a certain color

The color of the light depends on the material used.

Different voltages between 2-4 V are necessary in order to operate diodes of different colors in conducting direction.

Innovative LEDs offer a number of technological advantages:

  • Low energy consumption

  • Extremely long life

  • Very low early failure rate

  • Smallest dimensions

  • Shock and vibration resistant

  • No ultra-violet or infrared radiation

  • Low wattage

  • Directed light - Lambertian emitter with beam angle 120°

  • High color saturation

Main benefits for users:

Creative design options due to a multitude of available colors, compact dimensions and flexible modules

High economical efficiency due to low energy consumption, long life and low maintenance cost

Highest reliability even under difficult condition