Zeiss LSM 880, Operating Manual

Page: 133 / 690

CHAPTER 1 - SYSTEM OPERATION
LSM 880 Left Tool Area and Hardware Control Tools ZEISS
10/2014 V_01 000000-2071-464 127
5.2.11 Acquisition Parameter – Focus
Devices and Strategy
Focus Devices and Strategy
aims to maintain
focus stability in multi-dimensional acquisition
experiments.
This tool is typically employed to compensate for Z-
drift in time series experiments as well as for the
tilt of samples when recording at multiple positions
using a scanning stage.
Focus Devices and Strategy features four
different autofocus modes to be used in
combination with the acquisition tools
Time
Series
,
Tile Scan
and
Positions
.
These modes employ either the optional module Definite Focus or the built-in detection capabilities of
the LSM.
The set of available autofocus modes therefore depends upon a system's hardware configuration. The
LSM-based autofocus modes
Fluorescence , Reflection and Autofocus Map cannot be used if an
acquisition strategy includes tracks with camera-based image recording.
The
Focus Devices and Strategy
tool (Fig. 169) provides controls for maintaining focus stability with the
Tile Scan and Positions tools.
Autofocus Mode specifies the method to be used throughout the course of a
multi-dimensional experiment.
The menu for mode selection features a maximum of four active modes
(or Off mode):
−
Fluorescence
−
Reflection
−
Autofocus Map
−
Definite Focus
All LSM-based autofocus modes rely on the optical sectioning capabilities of a LSM for precisely locating
signal intensity maxima in the Z-direction.
The Z-position of an intensity maximum found within the search range is used as a reference for the
positioning of the imaging plane in the Z-direction.
In many cases, reference and imaging plane are not identical but differ by a fixed distance referred to as
offset (see Reflection and Autofocus Map modes below).
Whenever a focusing action is executed, the Z-position of the imaging plane is updated.
Fig. 169 Focus Devices and Strategy tool