Top posted for Brian`s ease of reading

Think phosphor blending is a dark art, tri phosphor tubes are pretty
much a standard over old halo phosphors nowadays but its the choice
and realative mix of the phosphors that makes a difference.

With a CRT can vary the level of excitation given to the phosphor.

In a fluro tube you coat the tube , dose it with its fill and seal it
up, its getting the blend of phosphors right with the right gas mix
and pressure to get a decent quality of light.

At other end of quality manufacture its possible to get light out
with just about any old mix , it might have a horrible green cast ,
but it produces light.

Nichia the company that developed the first white and blue LED`s are a
phosphor blending company going back to the 1950`s, until supporting
Shuji Nakamura to develop blue and white LEDs in the mid nineties.
Nichia still make the nicest white LEDs.

Some specialist fluros appear white but have a boost in one colour or
other, like the ones with a red boost intended for fresh meat
counters.

Still prefer halogen for living areas myself.

Cheers
Adam


On Jul 14, 1:59*pm, "Brian Gaff" wrote:
As an aside. If these are thre colour, and the idea is to make white from
red blue and green, and tvs use red blue and green to make white, then the
actual colour of the *colours of rg and b used must be way off on the lamps.
*When we used to make TVs in this fair land from scratch, we had a standard
white light made from yes a fl tube with calibrated *colour. That was back
in the 70s so I just do not get it, all I can think is that the perceived
efficiency is greater using this stuff.

Brian

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From the sofa of Brian Gaff -

Blind user, so no pictures please!"Arfa Daily" wrote in message

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"Brian Gaff" wrote in message
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Why is it that when one wants cfls, one is forced to have the weird light
output that many find hazy and *hard to see in? I'd have thought that the
really white *phosphoreds would add very little to the cost and be much
better for lighting purposes, or is the *cream/green/yellow fuzzy one
very much more efficient or something?
It even makes my eyes *feel tired even though I cannot see in it.

Brian

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From the sofa of Brian Gaff -

Blind user, so no pictures please!

I really don't know what it is about CFLs over linear flourescents. I have
absolutely no problem whatsoever seeing under incandescents or linears of
any colour persuasion, neither do I find their light objectionable in any
way. However, I hate the sickly light that CFLs generate, and have great
trouble reading under them. None of them of any colour temperature or CRI
seem to suit me. About the only thing that I can say is that they use a
tricolour phosphor mix, and this produces a highly discontinuous spectrum
compared to daylight or incandescent light, but then the spectrum from
linear flourescents isn't very clever, either.

Lots of people will now jump on the thread and say that they can't see
anything at all wrong with CFLs, and that the light from them is perfect
etc etc. Maybe this is true for them, and I'm sure most people, but it is
not for me, and apparently Brian. I do have a degree of colour blindness,
and maybe it's this, combined with the 'holey' spectrum, that combines to
make their light objectionable to me.

On a more practical level, I tried putting one in my bench light a while
back. Unfortunately, it was worse than useless for what I do (electronic
service work), as the discontinuous spectrum played havoc with being able
to correctly identify resistor colour code bands. Orange was barely
distinguishable from brown and sometimes red, and blue, green and grey
were also a problem with some resistor types. I have no such problems
working under incandescent light.

Arfa