In response to John Lupien:
My original comments:
>> I don't like to be pickey about this, but there should be less heat, not
>more.
>> If the bulbs are rated at the same wattage (ie. energy input) and a greater
>> proportion of that energy is emitted as visible light (ie. they are
>brighter),
>> then it follows that a smaller proportion must be emitted as heat.
>> Simple really!
>Over-simple, really. You appear to have left half of the non-visible
>spectrum out of your model. Perhaps there is less UV emitted, more IR,
>and more visible? Then you'd get more heat, more light, and not quite as
>good a tan...
I think that the assumption that light bulbs emit a significant amount of UV
is rather doubtful. Since less than 10% of the energy is emitted as visible
light and the vast majority of radiation energy is at lower frequencies (IR,
etc) I rather doubt that there is significant UV emitted by either normal or
halogen bulbs. Only discharge lights emit UV (and then only if the gasses in
the discharge path are optimised for this).
Can anyone comment on whether the energy input (wattage) of these bulbs is the
same as normal bulbs? That would seem to be a key issue!
Could it be that the 'problems' associated with halogen bulbs in plastic
lenses are an old-wives tale? Lots of people have heard of this, but has
anyone actually experienced any problems?
Simon (ever the skeptic) Matthews
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