Bicycle lighting has two purposes: seeing and being seen. There are many types of bicycle lights available, for example: b icycle light, bicycle head light , bicycle tail light, bicycle tail light, bicycle safety light, bicycle lighting, and so on. Each with its own advantages disadvantages.
The earliest bicycle and car lights were powered by acetylene (carbide) lamps, now almost unused except by cavers. They were dim and temperamental, and the arrival of battery lampswas welcomed. A common setup for a bicycle commuter might include:
a quartz-halogen or high power LED headlight powered by a rechargeable battery pack or dynamo;
a LED tail light, either steady or flashing/pulsating;
a flashing/pulsating LED front light for conspicuousness and as backup.
There is no one "best" solution of bicycle light for any rider, and many riders mix and match different technologies to provide the balance that works for them.
Replaceable-cell battery lights had a renaissance on the invention of alkaline batteries, with much higher storage densities. Moulding techniques for plastics also improved, allowing lens optics to be refined at low cost thus making more efficient use of the light output. During the 1980s the lighting market became more globalised: in Europe, the French "Wonder Lights" and Ever Ready brands gradually disappeared in favour of American, Japanese and German products.
In recent times, there have been many advances: exceptionally efficient dynamos; cheap high-output sealed-unit halogen lamps originally developed for decorative lighting; improved storage density in rechargeable batteries driven by the computer industry; high-output light emitting diodes (LEDs); white LEDs; high intensity discharge (HID) lights crossing over from the automotive sector.
References:
http://en.wikipedia.org/wiki/Bicycle_lighting
www.bicycle-head-light.com/cn/index.html