LED technology used in EVS signalling system

A groundbreaking innovation in LED technology opens up a completely new dimension in optical signalling. Enhanced Visibility System, or the electronic improvement of visibility, for EVS short, is the name WERMA has given to this latest development which promises to bring about a revolution in signal technology.

The flickering of neon lamps and comparable lighting effects are highly effective at attracting our attention. The neurobiological basis of this phenomenon is explained by a university scientist as follows: light signals are processed in the human brain, not directly in the eye. In order to be consciously registered there, incoming stimuli first have to pass through a form of filter. This filter has a ‘protective function’. During sleep it reduces disturbing stimuli to a minimum and assists in ‘overlooking’ regular or continuous signals.

Irregular light impulses can circumvent the brain’s filter function. Random light signals fail to generate an acclimatisation effect and the brain is unable to escape the stimulus, even when the flickering continues for an extended period.

On the basis of this understanding, WERMA’s R+D department set out to find a flickering light with a high degree of attracting attention. In a multistage laboratory experiment test candidates were asked to judge a series of different light signals and to determine the most eye-catching light. The result of the study was a stochastic flickering light with optimal attention-grabbing characteristics: EVS – Enhanced Visibility System. The light effect of this system is completely new and distinguishes it from all previous systems.

As a result of the extremely powerful signal effect, the EVS light is especially suited to signalling acute or highly important conditions. The EVS element can also be deployed in hazardous situations or in areas where immediate action is required.

For the EVS system WERMA employs light emitting diodes. A microprocessor generates random light signals. This gives the light a very ‘agitated’ character, which proves highly effective in drawing the attention of those in its vicinity – even when seen out of the corner of the eye.

Up to now LED signal devices have confined themselves to imitating the light effects of light bulbs or Xenon flashes, EVS however utilises the strengths of light emitting diodes. LEDs are capable of generating the required high flickering frequency with ease, frequencies which Xenon flashes for example are incapable of generating. There are a series of additional, classical advantage to LEDs – their resistance to vibration and shocks, their long life duration as well as their low energy consumption.