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The XPulse project aims to develop an innovative X-ray phase contrast mammographic system based on the use of laser plasma X-ray source. The demonstration of feasibility is at the heart of this presentation.

We present Hartmann wavefront sensors as versatile metrology tools to provide real-time characterization and optimization of sources as well as easy, at lambda optical alignment, on a spectral range from EUV to hard X-Ray.

Emergence of ultrafast EUV to X-ray sources, Free Electron Laser, High harmonic generation, betatron and Compton, has opened new paradigms in physical, chemical, biological and medical sciences by either producing ultrahigh intensities or for ultrafast imaging or by enabling pump-probe experiments at new timescales. Most of these experiments require an excellent or at least a properly defined wavefront (WF). A number of WF sensing techniques have been proposed in the X-Rays, including grating-based interferometry, speckle tracking, pencil beam deflectometry, or curvature sensors. Among these techniques, Hartmann WF sensing demonstrated a number of advantages, such as insensitivity to vibrations, achromaticity and very large dynamic range. Furthermore, the phase and intensity maps are directly retrieve and nearly instantaneously without the use of complex and long algorithms. Imagine Optic developed EUV to X-ray WF sensors since more than 15 years taking benefit of decades of experience in the visible range. We will show several experiments using our EUV sensors for metrology and optimization of ultrafast EUV sources. We recently developed a Hartmann sensor in the 5 - 25keV range. The device is based on a custom scintillator-to-detector optical relay system, as well as on an optimal Hartmann array geometry, providing 20µm spatial WF sampling resolution, over a 3x3 mm² pupil. We show the results of first experiments on a synchrotron beamline at 10 keV, achieving 4pm WF repeatability.

Since its creation in 1996, Imagine Optic designed and manufactured high performance Shack-Hartmann wavefront (WF) sensors for many kinds of applications such as telescope alignment, laser characterization, optics qualification or adaptive optics, and for many different fields such as space optics, microscopy, high power lasers or lithography. Since 2003, Imagine Optic is actively developing EUV to X-ray Hartmann WF sensors for applications on metrology beams emitted by synchrotrons, free-electron lasers, plasma-based soft X-ray lasers and high harmonic generation. Our most recent developments include the realization of a EUV sensor adapted to strongly convergent or divergent beams having numerical aperture as high as 0.15, as well as the production of a hard X-ray sensor working above 10 keV, providing outstanding repeatability as good as 4 pm rms. Our sensors have demonstrated their high usefulness for the metrology of EUV to X-ray optics from single flat or curved mirrors to more complex optical systems (Schwarzschild, Kirkpatrick-Baez static or based on bender technology or with activators). In terms of optics qualification is a clear advantage of actually measuring the wavefront at-wavelength. Also, we show active Kirkpatrick-Baez alignment in few minutes using our WF sensor in both manual and automatic loops at the benefit of strong improvement of the beam focalization on the sample. Recently we started developing our own compact deformable grazing incidence mirror bender. We present a review of the developed sensors, as well as experimental demonstrations of their benefits for optical metrology of various EUV and X-ray optics.

Imagine Optic (IO) is actively developing EUV to X-ray wavefront (WF) sensors since 2003 for applications on metrology of EUV to X-ray beams emitted by synchrotrons, free-electron lasers, plasma-based soft X-ray lasers and high harmonic generation. Our sensors have demonstrated their high usefulness for metrology of EUV to X-ray optics from single flat or curved mirrors to more complex optical systems (Schwarzschild, Kirkpatrick-Baez static or based on bender technology or with activators). Our most recent developments include the realization of a EUV sensor adapted to strongly convergent or divergent beams having numerical aperture as high as 0.15, as well as the production of a hard X-ray sensor working at 10 keV and higher energies, providing repeatability as good as 4 pm rms. We present a review of the developed sensors, as well as experimental demonstrations of their benefits for various metrology and WF optimization requirements.

Assessment of biodegradability of carbon nanotubes (CNTs) is a critically important aspect that needs to be solved before their translation into new biomedical tools. CNT biodegradation has been shown both in vitro and in vivo, but we are limited by the number of analytical techniques that can be used to follow the entire process. Photothermal imaging (PhI) is an innovative technique that enables the quantitative detection of nanometer-sized absorptive objects. In this study, we demonstrate that PhI allows the observation of the degradation process of functionalized multi-walled carbon nanotubes (MWCNTs) following their internalization by primary glial cells. The absence of interference from the biological matrix components, together with the possibility to combine PhI with other detection techniques (e.g. fluorescence, light or electron microscopy) validate the potential of this method to follow the fate and behavior of carbon nanostructures in a biological environment. journal article 2017 Apr 06 imported

We apply computational diffractive imaging to propose a new method for 3D imaging by using a diffractive optical component called Continuously Self Imaging Grating (CSIG).

In this Letter, we propose a method to perform 3D imaging with a simple and robust imaging system only composed of a continuously self-imaging grating (CSIG) and a matrix detector. With a CSIG, the intensity pattern generated by an object source is periodic and propagation invariant, apart from a dilatation factor that depends on the distance of the object. We demonstrate, theoretically and experimentally, how to exploit this property to analyze a scene in three dimensions. Such an imaging system can be used, for example, for tomographic applications.

An InfraRed (IR) cooled camera is generally composed by an optical block (warm lenses outside a dewar) and a detection block (a cooled focal plane array inside the dewar). A minimalist approach to design a compact and robust camera consists in giving the dewar an imaging function by replacing the cold pupil by a Diffractive Optical Element (DOE). In this paper we present different DOE that can be used to design the camera. We present first a pinhole camera that validates this approach but that is limited in radiometric performances and in angular resolution. We replace then the pinhole by a continuously self-imaging DOE, such as the diffractive axicon, to improve both the radiometric performances and the angular resolution. Finally, the MALDA is introduced to improve the performances of the axicon. Diffraction effects and Talbot effect under polychromatic light are exposed for such DOE and two different design rules are derived from those effects to allow the design of a compact camera with dimensions compatible with the size of an industrial dewar. Experimental prototypes are presented and radiometric performances are compared and show the best performances for the MALDA.

International audience; Diffractive Optical Elements (DOE), that generate a propagation-invariant transverse intensity pattern, can be used for metrology and imaging application because they provide a very wide depth of focus. However, exact implementation of such DOE is not easy, so we generally code the transmittance by a binary approximation. In this paper, we will study the influence of the binary approximation of Continuously Self-Imaging Gratings (CSIG) on the propagated intensity pattern, for amplitude or phase coding. We will thus demonstrate that under specific conditions, parasitic effects due to the binarization disappear and we retrieve the theoretical non-diffracting property of CSIG's.

In this paper, we demonstrate two image reconstruction schemes for continuously self-imaging gratings (CSIGs). CSIGs are diffractive optical elements that generate a depth-invariant propagation pattern and sample objects with a sparse spatial frequency spectrum. To compensate for the sparse sampling, we apply two methods with different regularizations for CSIG imaging. The first method employs continuity of the spatial frequency spectrum, and the second one uses sparsity of the intensity pattern. The two methods are demonstrated with simulations and experiments.

For more than 15 years, Imagine Optic have developed Extreme Ultra Violet (EUV) and X-ray Hartmann wavefront sensors for metrology and imaging applications. These sensors are compatible with a wide range of X-ray sources: from synchrotrons, Free Electron Lasers, laser-driven betatron and plasma-based EUV lasers to High Harmonic Generation. In this paper, we first describe the principle of a Hartmann sensor and give some key parameters to design a high-performance sensor. We also present different applications from metrology (for manual or automatic alignment of optics), to soft X-ray source optimization and X-ray imaging.