Interesting spectral phenomenon in coloured metal halide lamps

[dor123]

In the blue/high CCT and the green MH lamps spectra i found that the spectral lines of the indium (Blue and high CCT MH) and the thallium (Green MH) are dominant in the spectra from the moment the lamp is turn on (Like in the case of the run-up spectrum of a HPS lamp) unlike white MH lamps that these lines are not appearing in the spectrum during warm up but only after the mercury is reached its optimal pressure and intensity. This phenomenon is also occurs with the indium line (But not with the sodium line) in pink MH lamps. What cause the phenomenon?

[dor123]

Why anyone don't answers me?

[rjluna2]

I guess they haven't gotten an answer to you question yet.  Be patient

[dor123]

Why anyone don't answered my first question about the spectra of coloured MHs for more then one month?

[lights*plus]

Here's a very late reply that might fall on deaf ears.

From what I know.. Different lamps have different arc-starters in the arc-tube, typically xenon and mercury, which contribute their light at startup. It may happen that the thallium & indium in these M-H lamps are the arc-starters. This type of lamp however is rare. The very common M-H with sodium, mercury & scandium, ignites with the aid of mercury, followed by sodium and lastly the scandium lines appear.