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Dear All,
I am in the process of selecting a confocal microscope, and I would welcome
your views on a simple idea. My main application is excitation ratioing
(405nm blue diode laser / 488nm argon ion laser - emission >500nm).

The main (only?) difference between the LSM510 and the Pascal, besides
cost, is the ability to rapidly switch laser intensity using the AOTF - the
Pascal has a slower MOTF (mechanical >~1.5s switching rather than the
<microsecond AOTF). The AOTF, although essential for FRAP measurements, is
used simply as a shutter in most of my experiments. I wondered if I could
simply place an external shutter (maybe based on a defunct hard disk voice
coil) in the light path. If both lasers (405 & 488nm) were left on with
appropriate transmission, then the shutters could be used (switched by TTL)
to select the laser (on a frame by frame basis). Hence, I could achieve
much faster excitation-ratioing than the MOTF allows.

Can anyone see a fatal flaw with this plan? Indeed, maybe someone has
already done this?

Greetings,
Christof