Avoiding phantom light effects in traffic signals - using liquid crystals producing colour change from magnetic field effects

摘要

Installation in a light signal system to avoid phantom lighting effects. This is suitable for traffic or other signal installations where light-rays from the setting sun or other traffic users can create phantom lighting effects. The light signal installation has a light source, a collecting lens and a signal closing pane. A light transparent hollow element is fitted filled with liquid crystals and located within the effective area of a magnetic or electric field which can be switched on. In the liquid crystals a colour is dissolved which when the electric or magnetic field is switched which when the electric or magnetic filed is into a neutral colour.