Picometre-level surface control of a closed-loop, adaptive X-ray mirror with integrated real-time interferometric feedback

open access.

Bibliographische Detailangaben
Veröffentlicht in:Journal of synchrotron radiation. - 1994. - (2024) vom: 01. Jan.
1. Verfasser: Nistea, Ioana Theodora (VerfasserIn)
Weitere Verfasser: Alcock, Simon G, Foster, Andrew, Badami, Vivek, Signorato, Riccardo, Fusco, Matteo
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2025
Zugriff auf das übergeordnete Werk:Journal of synchrotron radiation
Schlagworte:Journal Article X-ray mirrors X-ray optics adaptive optics bimorph deformable mirrors closed-loop controls fibre optic interferometers high-voltage power supplies
LEADER 01000naa a22002652 4500
001 NLM381787605
003 DE-627
005 20241218232518.0
007 cr uuu---uuuuu
008 241218s2025 xx |||||o 00| ||eng c
024 7 |a 10.1107/S1600577524011007  |2 doi 
028 5 2 |a pubmed24n1635.xml 
035 |a (DE-627)NLM381787605 
035 |a (NLM)39692725 
040 |a DE-627  |b ger  |c DE-627  |e rakwb 
041 |a eng 
100 1 |a Nistea, Ioana Theodora  |e verfasserin  |4 aut 
245 1 0 |a Picometre-level surface control of a closed-loop, adaptive X-ray mirror with integrated real-time interferometric feedback 
264 1 |c 2025 
336 |a Text  |b txt  |2 rdacontent 
337 |a ƒaComputermedien  |b c  |2 rdamedia 
338 |a ƒa Online-Ressource  |b cr  |2 rdacarrier 
500 |a Date Revised 18.12.2024 
500 |a published: Print-Electronic 
500 |a Citation Status Publisher 
520 |a open access. 
520 |a We provide a technical description and experimental results of the practical development and offline testing of an innovative, closed-loop, adaptive mirror system capable of making rapid, precise and ultra-stable changes in the size and shape of reflected X-ray beams generated at synchrotron light and free-electron laser facilities. The optical surface of a piezoelectric bimorph deformable mirror is continuously monitored at 20 kHz by an array of interferometric sensors. This matrix of height data is autonomously converted into voltage commands that are sent at 1 Hz to the piezo actuators to modify the shape of the mirror optical surface. Hence, users can rapidly switch in closed-loop between pre-calibrated X-ray wavefronts by selecting the corresponding freeform optical profile. This closed-loop monitoring is shown to repeatably bend and stabilize the low- and mid-spatial frequency components of the mirror surface to any given profile with an error <200 pm peak-to-valley, regardless of the recent history of bending and hysteresis. Without closed-loop stabilization after bending, the mirror height profile is shown to drift by hundreds of nanometres, which will slowly distort the X-ray wavefront. The metrology frame that holds the interferometric sensors is designed to be largely insensitive to temperature changes, providing an ultra-stable reference datum to enhance repeatability. We demonstrate an unprecedented level of fast and precise optical control in the X-ray domain: the profile of a macroscopic X-ray mirror of over 0.5 m in length was freely adjusted and stabilized to atomic level height resolution. Aside from demonstrating the extreme sensitivity of the interferometer sensors, this study also highlights the voltage repeatability and stability of the programmable high-voltage power supply, the accuracy of the correction-calculation algorithms and the almost instantaneous response of the bimorph mirror to command voltage pulses. Finally, we demonstrate the robustness of the system by showing that the bimorph mirror's optical surface was not damaged by more than 1 million voltage cycles, including no occurrence of the `junction effect' or weakening of piezoelectric actuator strength. Hence, this hardware combination provides a real time, hyper-precise, temperature-insensitive, closed-loop system which could benefit many optical communities, including EUV lithography, who require sub-nanometre bending control of the mirror form 
650 4 |a Journal Article 
650 4 |a X-ray mirrors 
650 4 |a X-ray optics 
650 4 |a adaptive optics 
650 4 |a bimorph deformable mirrors 
650 4 |a closed-loop controls 
650 4 |a fibre optic interferometers 
650 4 |a high-voltage power supplies 
700 1 |a Alcock, Simon G  |e verfasserin  |4 aut 
700 1 |a Foster, Andrew  |e verfasserin  |4 aut 
700 1 |a Badami, Vivek  |e verfasserin  |4 aut 
700 1 |a Signorato, Riccardo  |e verfasserin  |4 aut 
700 1 |a Fusco, Matteo  |e verfasserin  |4 aut 
773 0 8 |i Enthalten in  |t Journal of synchrotron radiation  |d 1994  |g (2024) vom: 01. Jan.  |w (DE-627)NLM09824129X  |x 1600-5775  |7 nnns 
773 1 8 |g year:2024  |g day:01  |g month:01 
856 4 0 |u http://dx.doi.org/10.1107/S1600577524011007  |3 Volltext 
912 |a GBV_USEFLAG_A 
912 |a SYSFLAG_A 
912 |a GBV_NLM 
912 |a GBV_ILN_40 
912 |a GBV_ILN_350 
912 |a GBV_ILN_2005 
951 |a AR 
952 |j 2024  |b 01  |c 01