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Peynier, France

Daoudi K.,University of Twente | Van Den Berg P.J.,University of Twente | Rabot O.,Quantel Laser Diode | Kohl A.,Quantel Laser Diode | And 3 more authors.
Optics Express | Year: 2014

Ultrasound and photoacoustics can be utilized as complementary imaging techniques to improve clinical diagnoses. Photoacoustics provides optical contrast and functional information while ultrasound provides structural and anatomical information. As of yet, photoacoustic imaging uses large and expensive systems, which limits their clinical application and makes the combination costly and impracticable. In this work we present and evaluate a compact and ergonomically designed handheld probe, connected to a portable ultrasound system for inexpensive, real-time dualmodality ultrasound/photoacoustic imaging. The probe integrates an ultrasound transducer array and a highly efficient diode stack laser emitting 130 ns pulses at 805 nm wavelength and a pulse energy of 0.56 mJ, with a high pulse repetition frequency of up to 10 kHz. The diodes are driven by a customized laser driver, which can be triggered externally with a high temporal stability necessary to synchronize the ultrasound detection and laser pulsing. The emitted beam is collimated with cylindrical micro-lenses and shaped using a diffractive optical element, delivering a homogenized rectangular light intensity distribution. The system performance was tested in vitro and in vivo by imaging a human finger joint. © 2014 Optical Society of America. Source


Vial B.,Ecole Centrale Marseille | Commandre M.,Ecole Centrale Marseille | Zolla F.,Ecole Centrale Marseille | Nicolet A.,Ecole Centrale Marseille | Tisserand S.,Silios Technologies
AIP Conference Proceedings | Year: 2011

We analyze diffraction gratings via their resonances by a direct determination of the eigenmodes and the complex eigenfrequencies using a finite element method (FEM), that allows to study mono- or bi-periodic gratings with a maximum versatility: complex shaped patterns, with anisotropic and graded index material, under oblique incidence and arbitrary polarization. In order to validate our method, we illustrate an example of a four layer dielectric slab, and compare the results with a specific method that we have called tetrachotomy, which gives us numerically the poles of the reflection coefficient (which corresponds to the eigenfrequencies of the structure). © 2011 American Institute of Physics. Source


Daoudi K.,University of Twente | Van Den Berg P.J.,University of Twente | Rabot O.,Quantel Laser Diode | Kohl A.,Quantel Laser Diode | And 3 more authors.
Progress in Biomedical Optics and Imaging - Proceedings of SPIE | Year: 2013

Photoacoustics is a hybrid imaging modality that is based on the detection of acoustic waves generated by absorption of pulsed light by tissue chromophors. In current research, this technique uses large and costly photoacoustic systems with a low frame rate imaging. To open the door for widespread clinical use, a compact, cost effective and fast system is required. In this paper we report on the development of a small compact handset pulsed laser probe which will be connected to a portable ultrasound system for real-time photoacoustic imaging and ultrasound imaging. The probe integrates diode lasers driven by an electrical driver developed for very short high power pulses. It uses specifically developed highly efficient diode stacks with high frequency repetition rate up to 10 kHz, emitting at 800nm wavelength. The emitted beam is collimated and shaped with compact micro optics beam shaping system delivering a homogenized rectangular laser beam intensity distribution. The laser block is integrated with an ultrasound transducer in an ergonomically designed handset probe. This handset is a building block enabling for a low cost high frame rate photoacoustic and ultrasound imaging system. The probe was used with a modified ultrasound scanner and was tested by imaging a tissue mimicking phantom. © 2013 Copyright SPIE. Source


Patent
Silios Technologies | Date: 2015-08-24

A wavelength spectroscopy device includes, on a substrate, a filter cell CF constituted by two mirrors separated by a spacer membrane, the filter cell being made up of a plurality of interference filters. Furthermore, the device also includes an emission cell CE having a plurality of emission sources, each of the sources being associated with one of the interference filters.


Patent
Silios Technologies | Date: 2011-07-18

The invention relates to an optical probe including: Furthermore, the second cell C

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