On 2 Aug, 22:09, (Andrew Gabriel) wrote:

Halogen may well make a come-back too with a significant rise in
efficiency. A number of lamp manufacturers are working on halogen
(and other) filaments with micro pattening on the surface which
prevents emission of longer wavelengths (Infra-red), enabling the
filament to operate at the same temperature at significantly lower
power input.

Sounds interesting. Would any such patterning not evaporate fairly
soon? Do you have a link?


NT