LEDs have the following advantages:
- High light output: depending on LED type up to 100 Lumen/Watt and more
- Long service life: depending on LED type 50-70,000 hrs at 30% - 50% loss of luminous flux
- Coloured, saturated light: very good degree of effectiveness with colour-back-lit objects
- Shock-proof and vibration-proof: no breakage during transportation and installation
- Small dimensions: filigree style, flat applications possible+ Dimmable: 0 - 100%, loss-free
- Unlimited switching capability: rapid switching cycles without reductions in service life
- High degree of reliability at low temperatures: no start-up difficulties, no drop in luminous flux
The following points must be taken into account:
- Reduced service life in high temperatures: thermo management with high outputs and in ambient temperatures
- Restricted colour range for coloured LEDs: among other things no pastel shades, must be achieved using white LEDs, and associated reduction of efficiency
- Visible colour differences with white LEDs: this is especially visible when individual letters are repaired
- Higher investment costs: these generally pay themselves off over their service life as the result of lower energy consumption
Where are LEDs used?
LEDs are regarded as an energy-efficient and sustainable light source. However, their deployment requires professional design, planning, and implementation. LEDs are not the best solution for your illuminated signage in every case. Please ask our experts for advice.
We consider the main areas of use to be in small to medium-sized illuminated lettering. However, large roof installations and illuminated transparencies can be designed with ever more powerful LEDs. Single-sided illuminated signs, fascia boards, and pylons can also be illuminated efficiently. LEDs are also suitable for flat and filigree illuminants.
The switching and dimming capacity of LEDs makes possible the use of controls which depend on the ambient light. This allows the brightness to be controlled automatically, which represents an indispensable advantage when implementing the increasingly restrictive regulations regarding the brightness of illuminated signage imposed by regulatory authorities.
How do LEDs work?
Light-emitting diodes are electronic semi-conductor components. Light generation is based on the operating principle of electro-luminescence. The fluorescent colour (wavelength) is also dependent on the chemical composition of the semi-conductor materials.
LEDs emit very saturated, monochrome light in the colours red, orange, yellow, green and blue, and can thus be used very efficiently in illuminated signage. White light is the exception as this cannot be emitted directly by the semi-conductor.
The most common way of generating white light is based on the conversion principle, similar to the way it is generated in fluorescent lamps. Blue-emitting LEDs are coated with fluorescent paint. Today, these paints have been developed to such an extent that warm white LEDs are available (< 3300 K) with good colour rendering, colour constancy and efficiency, as well as cold white (> 5300 K) and neutral white ones (3300 - 5300 K).
White light can also be mixed additively from a red, green and blue LED (RGB LEDs). However, due to the different ageing characteristics of the three LEDs, it is difficult to guarantee colour constancy throughout the service life. RGB LEDs are mainly used for dynamic colour changes.