University of Twente spin-off · XUV Optics Group

Empowering Innovation with Custom X-Ray & EUV Optics

Unlock the potential of X-ray and EUV optics for your business and scientific research. Multilayer mirrors, monochromators, gratings, membranes and lenses — engineered layer by layer, atom by atom.

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Super-polished substrate Incident X-ray / EUV In-phase reflection
30years of experience
Recordreflectivity values at multiple wavelengths
40+relevant PhD dissertations
What we create

X-ray and EUV optics designed to meet your needs

From reflective multilayer mirrors to sub-micron focusing lenses — high-precision optics for metrology, analysis and research, validated in collaboration with leading industry partners.

Super-polished multilayer mirror substrate mounted in a deposition setupMirrors & monochromators

Reflective optics

High-precision X-ray and EUV mirrors and monochromators with perfectly tuned multilayer reflection — tailored to your wavelength and angular requirements.

SEM image of the periodic nanostructure of an EUV diffraction gratingEUV gratings

Diffractive optics

Design and production of EUV gratings with flawless nanostructure, enabling precise analysis of spectral compositions in the extreme ultraviolet range.

Free-standing silicon nitride membranes in wafer carriersSiN membranes

Transmissive optics

Highly durable free-standing silicon nitride membranes, down to 10 nm thick, produced in cleanroom facilities — with coatings for microscopy, optics or filtering.

SEM image of silicon refractive X-ray lens structures with 10 micrometre scale barSi refractive lenses

Refractive optics

High-precision silicon refractive lenses for sub-micron X-ray focusing, achieving spot sizes as small as 140 nm.

The multilayer principle

Precision layers, superior spectra

Our core technology is the deposition of reflective multilayer nano-films: hundreds of alternating layers, each a few atoms thick, acting as an artificial Bragg crystal. By optimising layer parameters we achieve superior spectral performance and absolute reliability.

Measured optical quality

Real measurement of one of our mirrors: the reflection sits right on the ultimate specification.

Measured intensity versus two-theta of a REX-Optics mirror, with the mirror reflection curve following the ultimate specification

Atomic-scale layer control

Design and realization — a TEM cross-section through one of our multilayers. This is how smooth our layers are.

Transmission electron microscope cross-section of a REX-Optics multilayer showing perfectly periodic smooth layers, 20 nanometre scale bar

Engineered interfaces

Decades of deposition expertise let us optimise every layer and interface, pushing reflectance towards theoretical limits while controlling stress and stability.

Tuned to your beamline

Wavelength, bandwidth, angle of incidence and substrate geometry are matched to your application — every optic is custom by design.

Industrially validated

Our quality is proven through long-standing collaborations with major industry players in semiconductor metrology and analytical instrumentation.

Applications

One technology, many beams

Our optics condition, disperse, filter and focus photons from soft X-rays to the extreme ultraviolet.

XRF — elemental analysis

Multilayer mirrors that isolate characteristic fluorescence lines for sensitive, accurate elemental analysis.

X-ray & EUV filtering

Ultra-thin silicon nitride membranes that transmit the photons you need and block everything else.

XRD — beam conditioning

Mirrors and monochromators that shape and monochromatise beams for high-resolution diffraction.

EUV spectrometry

Diffraction gratings for accurate light dispersion and spectral analysis in the extreme ultraviolet.

Synchrotron beamlines

Focusing mirrors, monochromators and complete beamline optics for large-scale facilities.

X-ray beam shaping

Silicon refractive lenses focusing X-ray beams down to 140 nm spots for imaging and probing.

About us

Dedication. Expertise. Passion.

REX-Optics was founded by experts from the Industrial Focus Group XUV Optics at the University of Twente — 30 years of research condensed into premium-quality specialised optics for metrology and research. We are dedicated to advancing the boundaries of optics innovation and customisation.

Portrait of Marcelo Ackermann

Marcelo Ackermann

Founder · Managing Director

Full Professor and Chair of the XUV Optics group, University of Twente.

Portrait of Arseniy Baskakov

Arseniy Baskakov

Founder · Managing Director

Physicist and entrepreneur (PhD, MBA) specialising in thin films and multilayer optics for X-ray applications.

Portrait of Fred Bijkerk

Fred Bijkerk

Founder

Senior Scientific and Valorisation Advisor.

Portrait of Andrey Yakshin

Andrey Yakshin

Founder

Assistant Professor, University of Twente — multilayer deposition expert.

Portrait of Igor Makhotkin

Igor Makhotkin

Founder

Group Lead, Computational Methods for Metrology & Sensors, ASML Research.

Portrait of Muharrem Bayraktar

Muharrem Bayraktar

Diffractive Optics Lead

Assistant Professor, University of Twente.

His Majesty King Willem-Alexander of the Netherlands visiting the XUV Optics laboratory, walking beside Professor Marcelo Ackermann
Royal visit

Recognised at the highest level

King Willem-Alexander of the Netherlands visiting the XUV Group Laboratory — the home of REX-Optics — with Professor Marcelo Ackermann, REX-Optics founder.

Contact

Let's design your optic

Tell us about your wavelength, geometry and performance targets — we will engineer the layers to match.

arseniybaskakov@rex-optics.com

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Controller: REX-Optics B.V., Drienerlolaan 5, 7522 NB Enschede, The Netherlands (KvK 97561029) — arseniybaskakov@rex-optics.com.

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