Table of Contents
Advertisement
FocusMonitor FM+
9.11
Automatic Caustic
In Automatic Caustic measurement mode, just press the start button to automatically determine a caustic.
The center position of the z-axis is preset as the start position.
The default setting for the number of measurement planes is 21. The optimal measurement range along the
z-axis and all other required settings are made automatically and adjusted if necessary. You can also make
advanced settings.
For stigmatic and single astigmatic beams, at least 10 different positions on the z-axis must be measured
according to ISO 11146-1. About half of the measurements must be distributed within one Rayleigh length on
both sides of the beam waist and about half must be distributed beyond two Rayleigh lengths starting from
the beam waist.
An odd number of measurement planes makes it more likely that a measurement planes is at or close to the
focal plane. PRIMES recommends measuring at least 21 planes within ± 3 Rayleigh lengths around the focus.
For generally astigmatic and unknown beams, ISO 11146-2 requires measurements to be made at a minimum
of 20 uniformly distributed points on the z-axis within a range of at least three times the Rayleigh length behind
and in front of the beam waist.
PRIMES recommends measuring at least 21 planes within ± 3 Rayleigh lengths around the focus.
An odd number of measurement planes makes it more likely that a measurement planes is at or close to the
focal plane.
9.11.1
Start measurement
1. Observe the warning messages in
chapter 9.1 „Warning messages" on
page 27.
2.
Click the Start button.
The measurement begins.
Optional:
X Click the Stop button to abort the
measurement.
X Click the Stop Rotation button to
stop the rotation of the measuring tip.
During the measurement, the progress
is shown in the following indicators:
Pre-caustic:
As the indication is being displayed, the
optimal measuring parameters such as
measuring window position, measuring
window size, integration time, and the
z-range (measuring range along the beam
propagation) are determined automatically.
Measuring caustic:
While the indicator is rotating, the measure-
ment is running.
Measurement completed:
After successful measurement, the indicator
lights up green.
3.
Switch off the laser after the measure-
ment is completed, unless you want
to perform further measurements.
Revision 08 EN - 08/2023
61
Advertisement
Table of Contents
