I.N. Galidakis said:
I have never seen a MH BL lamp. As far as I know, high pressure BL bulbs
are
optimized for emitting at 365nm.
MH lamps do not have mercury as their main emission ingredient, so that
would
make MH BL bulbs grossly inefficient, unless the additional materials
(such as
Sc) have strong emissions in the 340-400nm area.
Even if Sc emits in this area (one needs to check with NIST) I doubt that
the
emissions can match the intensity of the 365nm line in a HPM discharge.
If the lamp you saw was a BL, chances are it was a HPM.
"If the lamp you saw was a BL, chances are it was a HPM" -- That comment
from Ioannis fits with my experience too. The sodium-scandium general
lighting MH lamp emits some UV-A (and a little UV-B); but the overall UV-A
output/lumen is less than the HPM lamp and MH can't match the output from
the 365 nm mercury line. A paper which some colleagues and I wrote several
years ago has the comparison data in graphic form.
Download the figure with the irradiance comparison curves at:
https://download.yousendit.com/93EA82EF1878360B
Note that the data are normalized to "lumens" -- the eye sensitivity
curve -- since general lighting lamps were the source of the data and that
the vertical scale is logarithmic.
Terry McGowan
