History of Bicycle Lighting
The earliest bicycle and car lights were powered by acetylene, generated in a carbide lamp, now almost unused except by cavers. They were dim and temperamental, and the arrival of battery lamps was welcomed.
Early battery lamps generally used a lead-acid battery, but these were replaced by self-contained dry cells; lamps became smaller and more reliable. At the same time dynamos were developed which generated energy from the bicycle’s own movement. These were more practical, as storage density in batteries was at this time very low.
Not all jurisdictions required use of lights after dark. In the UK the law requiring use of rear lights was resisted by cyclists’ groups on the grounds that it downplayed motorists’ obligation to be able to stop well within the distance they can see to be clear.
Replaceable-cell battery lights had a renaissance on the invention of the alkaline battery, with a much higher storage density. 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.