Nils Nitzschke 11.06.2012

Lighthouses History Light system

Traffic lights History Light sources Phantom light

historyFirst lighthouse:

Alexandria 280bcHeight 115-160mVisibility range about 40km

First lighthouse in Germany:

Travemünde 1226Height 31mVisibility range about 33km

Light system

Until 1800 fire

1781 Argand hollow wick lamp

1870 Kerosene replaced oil

Since 1900 Electric lightMetal halide lamp (230v /400W)Metal halide lamp (230V / 2000W)Incandescent light bulb (220V / 2000W)

Light systemFresnel lens to produce parallel light

Light system

Position light

Direction light

historyFirst traffic light :London 1868Red and green gas lamp Exploded 2 weeks later

First electric traffic light:Salt Lake City 1914Red and greenDidn’t explode till now

Three color lamps:USA 1920Than Europe

Light sources in traffic lightsThree main types

Incandescent bulb230v / 60WMaintenance every 4 month

Incandescent bulb10V / 20WMaintenance every 6 month

Halogen bulb10V / 20WMaintenance every 6 month

Phantom signalSunlight reflected

on the front surface of the lampinside the optic of the lamp

Appears as if all lights give a signal

Phantom signalMeasures against phantom signal:

•Top cap

•Prismoptic

Phantom signalMeasures against phantom signal:

Lamellae

black top

silver bottom

Phantom signalMeasures against phantom signal:

LED lights

http://www.info-lsa.de/http://www.leuchttuerme.net/http://en.wikipedia.org/wiki/Lighthousehttp://en.wikipedia.org/wiki/Traffic_light