Is it possible to understand light?

Technical Facts

To talk about technical aspects or facts about lighting would be an over simplification of the subject at hand. The scientific understanding of light stemmed from Galileo’s ether theory, through to radiation and wave optics, to the quantum electrodynamic theories which are in constant change. It would be wise to accept that we have not yet understood light.

That said, the following is an attempt to summarize and to discuss questions of usage, particularly bulb types.


Buying a light bulb is not as easy as it used to be when the only consideration was wattage. What do the technical terms light bulb packaging mean? How do I figure out which bulb is the best light for me? What do lux, lumen and candela tell me about quality of light? How important is colour of a light?


To understand which light is suitable for which purpose, it is helpful to know how different types of bulbs and lights work. What are the differences between thermal radiators, discharge lamps and light emitting diodes? What technology is used to produce these lights? What kind of light to they emit?


Lamps, lights and luminaires: What types of lights are there? Which light is suitable for which purpose?