Airfield Lighting and Railway Lighting Systems

A colour emitted by a lamp system can be defined in terms of its chromatic coordinates (x and y) on the chromaticity diagram according to the 1931 Commission Internationale d’Eclairage (CIE) standard observer and coordinates system.

In the airfield lighting and railway signalling systems, all the above means that the colour of the filter used for those applications, does not shift when the lamp is warmed up avoiding the risk of dropping out of the acceptance specifications.

The extensive experience of ODL in thin film technology has led to the development of a process to get a denser structure of the dichroic films deposited under vacuum by the physical vapour deposition.
Besides a higher resistance to ambient pollution, a definite no temperature drift of the dichroic colour filters colour has been reached.
The advantage of the dichroic colour filters by ODL is that their colour coordinates do not change towards the temperature variation.
This means certainty of fulfilling the specifications, high degree of repeatability, no extra time spent in operational tests and finally less rejects.

The other great advantage obtained by the application of this new technology has been an improved long term stability of the filter.

ODL is able to provide those very stable colour dichroic filters in red, yellow, green and blue in accordance to any of the Transportation Chromatic Standard (FAA, AAR, ITE, ICAO, SAE).