J. Eur. Opt. Society-Rapid Publ. 21, 20( 2025) 203
Figure 8. MTF value detected at the position set as focus scan center. Initially this position represented the focus point, i. e. the z position with the highest MTF value. Coordinates given refer to the measurement setup coordinate system( cf. Fig. 1).
4 Conclusion
In this contribution, results of a change in the ambient temperature have been presented. The temperature-dependent shift of the focus point leads to a pronounced decrease of the MTF value obtained at the position that is considered as the focus point. This makes the stability of the ambient temperature a crucial condition for the uncertainty of the MTF measurement. It should be ensured that the ambient temperature has been kept constant during a measurement as well as for several hours before.
Funding This research received no external funding.
Conflicts of interest The authors have no conflicts of interest to disclose.
Data availability statement The data is available on request from the corresponding author.
Author contribution statement
Following the CRediT taxonomy, the contributions of each author are as follows: Hanno Dierke – Conceptualization, investigation, methodology, software, validation, visualization, and writing / review & editing of the original draft. Markus Schake – Methodology, software, supervision, validation, and reviewing.
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