We at Meridian have been extoling the virtues of ocular viewing confocal for
many years.  The improvements in productivity are phenomenal.  Both the
Yokogawa CSU10 and our own InSight Plus illuminate multiple locations within
the sample simultaneously to get the better signal to bleach performance, and
CCD output at up to video rates.  They use a scatter of points, while we line
them all up as a vertical laser cursor, which is swept across the specimen
120 times per second.  If you can't wait for their muticolor option, we have
it already on our InSights, which cost about the same and give better axial
resolution.

The improvement in resolution, even with thin specimens, is caused by
selective illumination at the points of interest, and happens even without a
confocal aperture.  Image from one volume within the specimen is not degraded
by stray light from other regions, since the rest of the specimen is dark
most of the time.

Note however that while illumination is focussed at one plane, it passes
through all others, so photobleaching can occur in planes which are not under
observation.  It is 2-photon which claims illumination at only one plane, but
even they have significant photon flux through all levels, perhaps with
concomitant optical trapping effects.

I have not seen a Yokogawa system but have followed their progress with
interest.  We haven't had a competitor with an ocular viewing CLSM since
BioRad gave up on their DWC.  I look forward to locking horns with them at
demos.

David Carter
Meridian Instruments Inc.
2310 Science Parkway
Okemos MI 48910
tel. 517 349 7617
fax 349 5967