LED Navigation Aids Guide Ships in All Japanese Coastal Waters

Copyright Japan Coast Guard

All navigation lights in Japan's coastal waters are now equipped with light emitting diodes (LEDs), according to a press release from the Japan Coast Guard (JCG). There are a total of 1,390 lighted aids (e.g. light buoys and floating lights) in Japanese waterways, and upon completion of the upgrade work on Nakanose Western No.1 Light Buoy in Tokyo Bay on February 14, 2009, all these aids are lighted with LEDs powered by solar or wave energy.

Navigation lights are used to ensure a safe and economical navigation. To increase their visibility in all weather conditions, and to reduce maintenance costs, JCG started to replace existing incandescent navigation lights with LED units in 1995. LEDs emit light with a wide divergence angle, excellent optical output, and quick response at on/off times, thereby offering high visibility to mariners. They also have a long usage life, which eliminates periodic replacement of bulbs, which is needed for conventional light sources. LED's low energy consumption can also allow them to fit in small units.

At the beginning of the LED replacement program, most of LEDs emitted low-intensity light in limited color options, which cold not fulfill the standards for navigation lights. Actually, in conformity to color specifications for navigation aids, only red LEDs were usable. However, thanks to the remarkable advancement of semiconductors, modern LEDs are available in white or green lights with improved lighting efficiency, broadening their applications in the area of nautical navigation.

Japan Coast Guard
http://www.kaiho.mlit.go.jp/e/index_e.htm

Posted: 2009/05/14 06:00:15 AM