> Maciau keista grafika, kur teigiama, kad dimerio funkcija prailgina lempos gyvavimo laika.

   Paprastoms kaitrinėms lempoms. Seniausia pasaulyje tebedeganti lempa
http://www.centennialbulb.org/facts.htm tokia ilgaamžė todėl, kad
vietoje 60 W šiuo metu šeriama vos 4 vatais. Šviesos kiekis simboliško
dydžio, bet ko nepadarysi dėl Gineso rekordų knygos :)
   Palyginimui, halogenai pažemintos įtampos nemėgsta.

http://en.wikipedia.org/wiki/Halogen_lamp:
With a reduced voltage the evaporation is lower and there may be too much
halogen, which can lead to abnormal failure. At much lower voltages, the
bulb temperature may be too low to support the halogen cycle, but by this
time the evaporation rate is too low for the bulb to blacken significantly.
There are many situations where halogen lamps are dimmed successfully.
However, lamp life may not be extended as much as predicted.

   Apie kitus tipus nežinau.

-- 
  saimhe