Confocal Microscopy (CFM) | Transmission
fundamentals
Transmission experiments in confocal microscopy sometimes also
require filtering and shaping of the optical beam, and hence free-beam
access instead of purely fiber-based can have quite some advantages in
terms of flexibility. for at least either the excitation or the detection to be free-beam. This
provides the user with all the flexibility of the external optics head just
like in case of the attoCFM I for one channel (plus potential reflection
measurements).
attoCFM IV At the same time, there are 3 degrees of freedom for the sample (xy
translation under the fixed LT-APO objective as well as focussing), and
another 3 degrees of freedom in xyz to position the fiber-based objec-
tive underneath the sample. All positioners are usually equipped with a
/RES encoder for closed loop control, and there is an additional scanner
for the sample in xy direction.
This instrument literally consists of a ‚conventional‘ attoCFM I, which
has a free-beam based channel with any of our apochromatic objectives
above the sample, and a fiber-based channel from below just like in the
attoCFM III.
So, despite fitting into any of our toploading cryostats, which usually
features only 1 top and no side or bottom windows, this setup allows
4
attocube
5
1
11
ASC400
3
2
6
7
8
X
Z
Y
X
Z
9
10
01 ASC400 scan controller 05 Optical top window 09 xyz positioner for fiber-based objective
02 LDM600 laser source* 06 Free-beam based cryogenic LT-APO objective 10 cryostat
03 LDM600 2nd detector 07 Sample with xyz positioners and optional xy scanner 11 vacuum feedthrough for single-mode fiber
04 attoCFM I external optics head incl. optional filters 08 Fiber-based cryogenic aspheric objective
S XY
Z
*incl. 50-50 coupler and detector
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