Moderators: Dave Moll, Andrew Davie, Steve Anderson
Steve Anderson wrote:Most (but not all) PMTs are sensitive in the shorter wavelength region, blue and UV.
By the time you get to the longer wavelength of green (the CRT phosphor) they are as good as totally deaf. Silicon is generally the other way around, better at red and IR. Cadmium sulfide (LDRs) has an approximate human eye response, but they're way too slow for this application. There really isn't an easy-to-suggest alternative...maybe a Plumbicon camera tube optomised for green?
But that's a real hassle, don't even consider bothering...or (not easy) getting hold of a CRT with a blue phosphor....A P7 CRT maybe possible. It has a short blue flash followed by the very slow yellow/orange afterglow which the PMT will ignore...a suggestion, though not guaranteed. How short is that 'blue flash'? I really don't know, it still could be too long for what you are attempting to do here...
Steve A.
Steve Anderson wrote:Hmm, this comes as no surprise to me, two quite different CRTs requiring differing amounts of deflection drive, and whatever supply voltages might be needed for each. Nothing much to suggest here, it's a case of "ho hum" I guess...
Wish I could be more helpful...
Steve A.
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