Une. Alignement de configuration <ol><li> Commencez par aligner à peu près le laser, le faisceau de expender, l&#39;objectif et l&#39;appareil photo sur le même axe, ce qui serait l&#39;axe optique. </li><li> Allumez le laser (sans la cible USAT), et assurez-vous que la lumière passe à travers le centre de la lentille. Utilisez un iris d&#39;ouverture pour vérifier. </li><li> Allumez l&#39;appareil photo et assurez-vous que la lumière se concentre sur le centre de l&#39;appareil photo. </li><li> Rétrograder la caméra, en utilisant l&#39;étape de z linéaire. Depuis que le système va de mise au point, la tache de lumière va croître. Assurez-vous que le centre de la tache reste dans la même position latérale. Si non, modifier attentivement la position du système d&#39;imagerie et répétez cette étape jusqu&#39;à ce que l&#39;endroit reste à la même position dans l&#39;espace, à un niveau de pixel. </li></ol> 2. Imagerie à Trois avions Defocus <ol><li> Insérer la cible d&#39;essai devant l&#39;ecarteur de faisceau. Placer la cible de sorte que la lumière qui passe à travers elle passera èmele centre approximatif de la lentille. </li><li> Capturer une image. Cette image sera un point d&#39;ancrage, et son emplacement sera z 0, x 0 (toutes les autres images seront en référence à son emplacement). Cette image sera I 1, b. </li><li> Maj dos de l&#39;appareil photo (en utilisant l&#39;étape de z linéaire) sur une distance de dz = 5,08 mm (ou 0,2 po) et capturer une image. Cette image sera I 2, b. </li><li> Rétrograder la caméra une autre distance de dz = 5,08 mm (10,16 mm par rapport à z 0) et capturer une image. Cette image sera I 3, b. </li><li> Retour à z 0. </li></ol> 3. Numérisation de l&#39;ouverture <ol><li> Déplacer le système d&#39;imagerie entière latéralement (à l&#39;aide de la phase linéaire x) sur une distance de 2,5 mm = dx et capturer une image. Cette image sera I 1, un. </li><li> Répétez le processus dans le protocole 2. Décaler en arrière de la caméra (en utilisant l&#39;étape de z linéaire) sur une distance de dz = 5,08 mm, et capturer une image (I 2, a). Rétrograder ee une autre distance de la caméra dz = 5,08 mm, et capturer une image (I 3, a). </li><li> Maintenant, répétez la procédure pour l&#39;autre côté. Déplacer le système d&#39;imagerie d&#39;une distance de dx = -2,5 mm et de capturer un ensemble de trois images en trois positions z (I 1 à 3, c). </li><li> Retour à z 0, x 0. </li></ol> 4. Phase de recherche (calcul numérique) <ol><li> Utilisation de la méthode des trois avions de 14, et les images que je 1-3, b, récupérer la phase optique de l&#39;image I 1, b. Utilisant la phase qui a été récupéré, définir q 1, b. </li><li> Surveiller le coefficient de corrélation entre I 1, b et | q 1, b | 2, afin de vérifier que le processus itératif ne converge. Pour ce faire, utilisez la fonction &#39;corr2&#39; dans MATLAB. </li><li> Répétez le processus de récupération de phase I 1-3, un, et je 1-3, c. </li></ol> 5. L&#39;image de Super Résolu (calcul numérique) <ol><li> Uchanter Fresnel libre propagation de l&#39;espace (FSP) solidaire 15, retour propager les champs q 1, ca au plan de la lentille. Ces champs seront lentille Ê, ac +. </li><li> Multiplier les champs résultants objectif Ê, ac + par exp (+ πix 0 2) / λf), afin de passer à travers la lentille. Ces champs seront lentille Ê, ac -. </li><li> Afin de placer la lentille de champ Ê, un dans sa position d&#39;origine, le déplacer latéralement sur ​​une distance de dx = 2,5 mm. </li><li> Afin de placer la lentille de champ Ê, c dans sa position d&#39;origine, le déplacer latéralement sur ​​une distance de dx = -2,5 mm. </li><li> Résumer l&#39;objectif de trois champs, courant alternatif, afin de les combiner et augmenter la taille de l&#39;ouverture synthétique. </li><li> Multiplier le champ résultant par exp (-πix 0 2) / λf), et l&#39;espace libre se propager à l&#39;image plane. </li><li> Une amélioration de la résolution d&#39;un facteur of 3 dans la direction de balayage doit être assisté. </li></ol>

<ol>
	<li>De Loor, G. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Possibilities+and+uses+of+radar+and+thermal+infrared+systems.">Possibilities and uses of radar and thermal infrared systems.</a> Photogrammetria. 24, 43-58 (1969).</li><li>Simonett, D. S. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Remote+sensing+with+imaging+radar:+A+review.">Remote sensing with imaging radar: A review.</a> Geoforum. , 61-74 (1970).</li><li>Born, M., Wolf, E. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Principles of optics: electromagnetic theory of propagation, interference and diffraction of light. , (1999).</li><li>Wiley, C. A. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Synthetic+aperture+radars-a+paradigm+for+technology+evolution.">Synthetic aperture radars-a paradigm for technology evolution.</a> IEEE Trans. Aerospace Elec. Sys. 21, 440-443 (1985).</li><li>Brown, W., Porcello, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> An introduction to synthetic-aperture radar. , 52-62 (1969).</li><li>Cheney, M., Borden, B. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=.">.</a> Fundamentals of Radar Imaging. Siam. , (2008).</li><li>Otto, R., Fritz, L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Die+lehre+von+der+bildentstehung+im+mikroskop+von+Ernst+Abbe.">Die lehre von der bildentstehung im mikroskop von Ernst Abbe.</a> Vieweg Braunschweig. , (1910).</li><li>Gerchberg, W. R., Saxton, W. O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+practical+algorithm+for+the+determination+of+phase+from+image+and+diffraction+plane+pictures.">A practical algorithm for the determination of phase from image and diffraction plane pictures.</a> Optik. 35, 237-246 (1972).</li><li>Misell, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+method+for+the+solution+of+the+phase+problem+in+electron+microscopy.">A method for the solution of the phase problem in electron microscopy.</a> J. Phys. D Appl. Phys. 6, (1973).</li><li>Misell, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+examination+of+an+iterative+method+for+the+solution+of+the+phase+problem+in+optics+and+electron+optics:+I.+Test+calculations.">An examination of an iterative method for the solution of the phase problem in optics and electron optics: I. Test calculations.</a> J. Phys. D Appl. Phys. 6, 2200-2216 (1973).</li><li>Misell, D. L. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=An+examination+of+an+iterative+method+for+the+solution+of+the+phase+problem+in+optics+and+electron+optics.">An examination of an iterative method for the solution of the phase problem in optics and electron optics.</a> II. Sources of error. J. Phys. D Appl. Phys. 6, 2217-2225 (1973).</li><li>Fienup, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Reconstruction+of+an+object+from+the+modulus+of+its+Fourier+transform.">Reconstruction of an object from the modulus of its Fourier transform.</a> Optics Lett. 3, 27-29 (1978).</li><li>Fienup, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Phase+retrieval+algorithms:+a+comparison.">Phase retrieval algorithms: a comparison.</a> Appl. Optics. 21, 2758-2769 (1982).</li><li>Gur, E., Zalevsky, Z. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Image+deblurring+through+static+or+time-varying+random+perturbation+medium.">Image deblurring through static or time-varying random perturbation medium.</a> J. Electron. Imaging. 18, 033016-03 (2009).</li><li>Goodman, J. W. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Introduction+to+Fourier+Optics.">Introduction to Fourier Optics.</a> Roberts &amp; Company. , (2005).</li><li>Tippie, A. E., Kumar, A., Fienup, J. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=High-resolution+synthetic-aperture+digital+holography+with+digital+phase+and+pupil+correction.">High-resolution synthetic-aperture digital holography with digital phase and pupil correction.</a> Optics Express. 19, 12027-12038 (2011).</li><li>Lim, S., Choi, K., Hahn, J., Marks, D. L., Brady, J. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Image-based+registration+for+synthetic+aperture+holography.">Image-based registration for synthetic aperture holography.</a> Optics Express. 19, 11716-11731 (2011).</li></ol>

Il n&#39;y a rien à divulguer.

L&#39;optique radar à ouverture synthétique (OSAR) concept qui est présenté dans ce document est une nouvelle approche de super-résolue qui utilise l&#39;algorithme GS et technique de balayage afin d&#39;améliorer la résolution spatiale d&#39;un objet dans le sens de la recherche. Le mouvement de la plate-forme d&#39;imagerie peut être auto-généré tout en utilisant une plate-forme aéroportée ou satellite. Contrairement à de nombreuses techniques de multiplexage dans le temps de SR, notre procédé ne néce...

Dans l&#39;imagerie radar, un faisceau étroit de l&#39;angle de l&#39;impulsion radiofréquence (RF) est transmis en utilisant une antenne qui est montée sur une plate-forme. Le signal de radar émet dans une direction latérale-regardant vers la surface de 1,2. Le signal réfléchi est rétrodiffusée à partir de la surface et est reçu par la même antenne 2. Les signaux reçus sont convertis en une image radar. En radar à ouverture réelle (RAR) la résolution dans la direction d&#39;azimut est proportionnelle à la longueur d&#39;onde et inversement proportionnelle à la dimension de l&#39;ouverture 3. Ainsi, une plus grande antenne est nécessaire pour une meilleure résolution en azimut. Cependant, il est difficile de fixer une grande antenne à des plates-formes mobiles telles que des avions et des satellites. En 1951, Wiley 4 proposé une nouvelle technique de radar appelé radar à synthèse d&#39;ouverture (SAR), qui utilise l&#39;effet Doppler créée par le mouvement de la plate-forme d&#39;imagerie. En SAR, l&#39;amplitude et la phase du signal reçu sont enregistrés 5 </sup&gt;. Ceci est possible étant donné que la fréquence optique de RS est de 1 à 100 GHz environ 6 et la phase est enregistré en utilisant un résonateur de référence locale installée sur le dessus de la plate-forme. Dans l&#39;imagerie optique, des longueurs d&#39;onde plus courtes sont utilisées, telles que le visible et le proche infrarouge (NIR), qui est d&#39;environ 1 pm, c&#39;est à dire la fréquence d&#39;environ 10 Hz. 14. L&#39;intensité de champ, plutôt que le champ lui-même, est détecté depuis les changements de phase optique trop rapides pour la détection à l&#39;aide de détecteurs à base de silicium standard. Bien que l&#39;imagerie d&#39;un objet à travers un système optique, l&#39;ouverture de l&#39;optique sert de filtre passe-bas. Ainsi, la haute fréquence d&#39;information spatiale de l&#39;objet est perdu 7. Dans cet article, nous nous efforçons de résoudre chacun des problèmes mentionnés ci-dessus séparément, à savoir la phase perdu et l&#39;effet de la limite de diffraction. Gerchberg et Saxton (GS) 8 ont suggéré que la phase optique peut être Retrieved en utilisant un processus itératif. Misell 9-11 a étendu l&#39;algorithme pour deux avions tout d&#39;entrée et de sortie. Ces approches ont fait leurs preuves à converger vers une distribution de phase avec une erreur quadratique moyenne minimale (MSE) 12,13. Gur et Zalevsky 14 ont présenté une méthode à trois des avions qui améliore l&#39;algorithme Misell. Nous proposons et démontrons expérimentalement que la restauration de la phase tout en déplaçant la lentille d&#39;imagerie, comme cela se fait avec l&#39;antenne en application de SAR nous permet d&#39;augmenter de manière synthétique la taille effective de l&#39;ouverture le long de l&#39;axe de balayage et, éventuellement, améliorer la résolution de l&#39;imagerie abouti. L&#39;application de la SAR dans l&#39;imagerie optique par interférométrie et l&#39;holographie est bien connu 16,17. Cependant, la méthode proposée est destinée à imiter une plate-forme d&#39;imagerie à balayage, ce qui convient pour l&#39;imagerie non cohérente (comme plate-forme aéroportée visée latérale). Ainsi, le concept de l&#39;holographie, la WHIch utilise un faisceau de référence, n&#39;est pas adapté à une telle application. Au lieu de cela, l&#39;algorithme de Gerchberg-Saxton révisée est utilisée afin de récupérer la phase.

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		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Red Laser Module</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=LDM635">LDM635</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">10X Galilean Beam Expander</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=BE10M-A">BE10M-A</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Negative 1951 USAF Test Target</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=R3L3S1N">R3L3S1N</a></td>
			<td style="width:261px;"></td>
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		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Filter holder for 2&#34; Square Filters</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=FH2">FH2</a></td>
			<td style="width:261px;"></td>
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		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">1&#34; Linear Translation Stage</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=PT1">PT1</a></td>
			<td style="width:261px;">X2</td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Lens Mount for &#216;1&#34; Optics</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=LMR1">LMR1</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Lens f = 100.0mm</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=AC254-100-A">AC254-100-A</a></td>
			<td style="width:261px;"></td>
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		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">Graduated Ring-Activated Iris Diaphragm</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://www.thorlabs.com/thorproduct.cfm?partnumber=SM1D12C">SM1D12C</a></td>
			<td style="width:261px;"></td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">2.5x2.5mm Aperture &#216;1&#34;</td>
			<td style="width:311px;"></td>
			<td style="width:259px;"></td>
			<td style="width:261px;">Indoor production</td>
		</tr>
		<tr height="22">
			<td align="left" height="22" style="height:22px;width:311px;">High Resolution CMOS Camera</td>
			<td style="width:311px;">Thorlabs</td>
			<td style="width:259px;"><a href="http://thorlabs.com/thorProduct.cfm?partNumber=DCC1545M">DCC1545M</a></td>
			<td style="width:261px;"></td>
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time multiplexing super resolving technique for imaging from a moving platform

Nous proposons un procédé pour augmenter la résolution d&#39;un objet et de surmonter la limite de diffraction d&#39;un système optique installé sur le dessus d&#39;un système de formation d&#39;image en mouvement, tel qu&#39;une plate-forme aéroportée ou satellite. L&#39;amélioration de la résolution est obtenue dans un processus en deux étapes. Tout d&#39;abord, trois basse résolution des images différemment DÉFOCALISÉES sont capturés et la phase optique sont récupérées à l&#39;aide d&#39;un algorithme basé Gerchberg-Saxton itérative améliorée. La récupération de phase permet de propager numériquement retour sur le terrain pour le plan d&#39;ouverture. Deuxièmement, le système de formation d&#39;image est décalée et la première étape est répétée. Les champs optiques obtenues au niveau du plan d&#39;ouverture sont réunies et une ouverture d&#39;objectif est généré par synthèse accrue le long de la direction de déplacement, ce qui donne une meilleure résolution d&#39;image. La méthode ressemble à une approche bien connue du régime micro-ondes appelé le radar à ouverture synthétique (SAR), dans laquelle la taille de l&#39;antenne est synthétique a augmenté le long de la plate-formedirection de propagation. La méthode proposée est démontrée par l&#39;expérience de laboratoire.

<html> Un exemple pour les neuf images capturées (trois images de défocalisation dans trois positions latérales) est représenté sur la figure 3. Un exemple de la convergence GS est représenté sur la figure 4. Le coefficient de corrélation pour l&#39;image centrale I 1, b est supérieur à 0,95, et le coefficient de corrélation pour les images secondaires I 1, a et I 1, c est supérieur à 0,85 (dans la simulation num?...

Watch this Scientific Journal Video about Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform at JoVE.com

Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Un procédé pour surmonter la limite de diffraction optique est présenté. Le procédé comprend un processus en deux étapes: l&#39;extraction de phase optique en utilisant l&#39;algorithme itératif Gerchberg-Saxton, et le déplacement du système de formation d&#39;image suivie d&#39;une répétition de la première étape. Une ouverture de l&#39;objectif par synthèse accrue est générée le long de la direction de déplacement, ce qui donne une meilleure résolution d&#39;image.

Multiplexage temporel de Super Résolution technique d&#39;imagerie à partir d&#39;une plate-forme mobile

We propose a method for increasing the resolution of an object and overcoming the diffraction limit of an optical system installed on top of a moving ...

time-multiplexing-super-resolving-technique-for-imaging-from-moving

Research

JoVE Journal

Engineering

8.3K vues.  Bar-Ilan University.  Un procédé pour surmonter la limite de diffraction optique est présenté. Le procédé comprend un processus en deux étapes: l'extraction de phase optique en utilisant l'algorithme itératif Gerchberg-Saxton, et le déplacement du système de formation d'image suivie d'une répétition de la première étape. Une ouverture de l'objectif par synthèse accrue est générée le long de la direction de déplacement, ce qui donne une meilleure résolut...

Vidéo: Time Multiplexing Super Resolving Technique for Imaging from a Moving Platform

Visualization of High Speed Liquid Jet Impaction on a Moving Surface

Two apparatuses for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device (for examining surface speeds between 0 and 25 m/sec) and a spinning disk device (for examining surface speeds between 15 and 100 m/sec). The air cannon linear traverse is a pneumatic energy-powered system that is designed to accelerate a metal rail surface mounted on top of a wooden projectile. A pressurized cylinder fitted with a solenoid valve rapidly releases pressurized air into the barrel, forcing the projectile down the cannon barrel. The projectile travels beneath a spray nozzle, which impinges a liquid jet onto its metal upper surface, and the projectile then hits a stopping mechanism. A camera records the jet impingement, and a pressure transducer records the spray nozzle backpressure. The spinning disk set-up consists of a steel disk that reaches speeds of 500 to 3,000 rpm via a variable frequency drive (VFD) motor. A spray system similar to that of the air cannon generates a liquid jet that impinges onto the spinning disc, and cameras placed at several optical access points record the jet impingement. Video recordings of jet impingement processes are recorded and examined to determine whether the outcome of impingement is splash, splatter, or deposition. The apparatuses are the first that involve the high speed impingement of low-Reynolds-number liquid jets on high speed moving surfaces. In addition to its rail industry applications, the described technique may be used for technical and industrial purposes such as steelmaking and may be relevant to high-speed 3D printing.

Two experimental devices for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device and a spinning disk device. The apparatuses are used to determine optimal approaches to the application of liquid friction modifier (LFM) onto rail tracks for top-of-rail friction control.

Visualisation de High Speed ​​Liquid Jet impaction sur une surface en mouvement

Two apparatuses for examining liquid jet impingement on a high-speed moving surface are described: an air cannon device (for examining surface speeds ...

Recherche

Ingénierie

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus have potential applications in nonlinear optics, which requires extraordinary optical intensity. One of the most studied nonlinearities in plasmonics is nonlinear absorption, including saturation and reverse saturation behaviors. Although scattering and absorption in nanoparticles are closely correlated by the Mie theory, there has been no report of nonlinearities in plasmonic scattering until very recently. 
Last year, not only saturation, but also reverse saturation of scattering in an isolated plasmonic particle was demonstrated for the first time. The results showed that saturable scattering exhibits clear wavelength dependence, which seems to be directly linked to the localized surface plasmon resonance (LSPR). Combined with the intensity-dependent measurements, the results suggest the possibility of a common mechanism underlying the nonlinear behaviors of scattering and absorption. These nonlinearities of scattering from a single gold nanosphere (GNS) are widely applicable, including in super-resolution microscopy and optical switches. 
In this paper, it is described in detail how to measure nonlinearity of scattering in a single GNP and how to employ the super-resolution technique to enhance the optical imaging resolution based on saturable scattering. This discovery features the first super-resolution microscopy based on nonlinear scattering, which is a novel non-bleaching contrast method that can achieve a resolution as low as l/8 and will potentially be useful in biomedicine and material studies.

Saturable and reverse saturable scattering were discovered in isolated plasmonic particles and adopted as a novel non-bleaching contrast method in super-resolution microscopy. Here the experimental procedures of detecting and extracting nonlinear scattering are explained in detail, as well as how to enhance resolution with the aid of saturated excitation microscopy.

Mesure de la diffusion non-linéarités d&#39;une nanoparticule plasmonique Simple

Plasmonics, which are based on the collective oscillation of electrons due to light excitation, involve strongly enhanced local electric fields and thus ...

Use of a Multi-compartment Dynamic Single Enzyme Phantom for Studies of Hyperpolarized Magnetic Resonance Agents

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due to fundamental constraints imposed by the hyperpolarized state, exotic imaging and reconstruction techniques are commonly used. A practical system for characterization of dynamic, multi-spectral imaging methods is critically needed. Such a system must reproducibly recapitulate the relevant chemical dynamics of normal and pathological tissues. The most widely utilized substrate to date is hyperpolarized [1-13C]-pyruvate for assessment of cancer metabolism. We describe an enzyme-based phantom system that mediates the conversion of pyruvate to lactate. The reaction is initiated by injection of the hyperpolarized agent into multiple chambers within the phantom, each of which contains varying concentrations of reagents that control the reaction rate. Multiple compartments are necessary to ensure that imaging sequences faithfully capture the spatial and metabolic heterogeneity of tissue. This system will aid the development and validation of advanced imaging strategies by providing chemical dynamics that are not available from conventional phantoms, as well as control and reproducibility that is not possible in vivo.

A multi-compartment dynamic phantom is used to simulate some biology of interest for metabolic studies using hyperpolarized magnet resonance agents.

Utilisation d&#39;un multi-compartiment dynamique unique Enzyme Phantom pour les études de hyperpolarisé Agents de résonance magnétique

Imaging of hyperpolarized substrates by magnetic resonance shows great clinical promise for assessment of critical biochemical processes in real time. Due ...

A High Performance Impedance-based Platform for Evaporation Rate Detection

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was employed here for demonstration purposes. Multiple evaporation tests on the model compound as a humectant with various concentrations in solutions were conducted for comparison purposes. A conventional weight loss approach is known as the most straightforward, but time-consuming, measurement technique for evaporation rate detection. Yet, a clear disadvantage is that a large volume of sample is required and multiple sample tests cannot be conducted at the same time. For the first time in literature, an electrical impedance sensing chip is successfully applied to a real-time evaporation investigation in a time sharing, continuous and automatic manner. Moreover, as little as 0.5 ml of test samples is required in this impedance-based apparatus, and a large impedance variation is demonstrated among various dilute solutions. The proposed high-sensitivity and fast-response impedance sensing system is found to outperform a conventional weight loss approach in terms of evaporation rate detection.

This paper presents an impedance-based apparatus for evaporation rate detection of solutions. It offers clear advantages over a conventional weight loss approach: a fast response, high-sensitivity detection, a small sample requirement, multiple sample measurements, and easy disassembly for cleaning and reuse purposes.

Une plate-forme pour la détection Taux d&#39;évaporation à base d&#39;impédance haute performance

This paper describes the method of a novel impedance-based platform for the detection of the evaporation rate. The model compound hyaluronic acid was ...

A Robotic Platform to Study the Foreflipper of the California Sea Lion

The California sea lion (Zalophus californianus), is an agile and powerful swimmer. Unlike many successful swimmers (dolphins, tuna), they generate most of their thrust with their large foreflippers. This protocol describes a robotic platform designed to study the hydrodynamic performance of the swimming California sea lion (Zalophus californianus). The robot is a model of the animal&#39;s foreflipper that is actuated by motors to replicate the motion of its propulsive stroke (the &#39;clap&#39;). The kinematics of the sea lion&#39;s propulsive stroke are extracted from video data of unmarked, non-research sea lions at the Smithsonian Zoological Park (SNZ). Those data form the basis of the actuation motion of the robotic flipper presented here. The geometry of the robotic flipper is based a on high-resolution laser scan of a foreflipper of an adult female sea lion, scaled to about 60% of the full-scale flipper. The articulated model has three joints, mimicking the elbow, wrist and knuckle joint of the sea lion foreflipper. The robotic platform matches dynamics properties&#8212;Reynolds number and tip speed&#8212;of the animal when accelerating from rest. The robotic flipper can be used to determine the performance (forces and torques) and resulting flowfields.

A robotic platform is described that will be used to study the hydrodynamic performance&#8212;forces and flowfields&#8212;of the swimming California sea lion. The robot is a model of the animal&#39;s foreflipper that is actuated by motors to replicate the motion of its propulsive stroke (the &#39;clap&#39;).

Une plate-forme robotique pour étudier la Foreflipper de la mer Lion Californie

The California sea lion (Zalophus californianus), is an agile and powerful swimmer. Unlike many successful swimmers (dolphins, tuna), they generate most ...

Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy (ATOM)

Scaling the number of measurable parameters, which allows for multidimensional data analysis and thus higher-confidence statistical results, has been the main trend in the advanced development of flow cytometry. Notably, adding high-resolution imaging capabilities allows for the complex morphological analysis of cellular/sub-cellular structures. This is not possible with standard flow cytometers. However, it is valuable for advancing our knowledge of cellular functions and can benefit life science research, clinical diagnostics, and environmental monitoring. Incorporating imaging capabilities into flow cytometry compromises the assay throughput, primarily due to the limitations on speed and sensitivity in the camera technologies. To overcome this speed or throughput challenge facing imaging flow cytometry while preserving the image quality, asymmetric-detection time-stretch optical microscopy (ATOM) has been demonstrated to enable high-contrast, single-cell imaging with sub-cellular resolution, at an imaging throughput as high as 100,000 cells/s. Based on the imaging concept of conventional time-stretch imaging, which relies on all-optical image encoding and retrieval through the use of ultrafast broadband laser pulses, ATOM further advances imaging performance by enhancing the image contrast of unlabeled/unstained cells. This is achieved by accessing the phase-gradient information of the cells, which is spectrally encoded into single-shot broadband pulses. Hence, ATOM is particularly advantageous in high-throughput measurements of single-cell morphology and texture &#8211; information indicative of cell types, states, and even functions. Ultimately, this could become a powerful imaging flow cytometry platform for the biophysical phenotyping of cells, complementing the current state-of-the-art biochemical-marker-based cellular assay. This work describes a protocol to establish the key modules of an ATOM system (from optical frontend to data processing and visualization backend), as well as the workflow of imaging flow cytometry based on ATOM, using human cells and micro-algae as the examples.

Microfluidic Imaging Flow Cytometry by Asymmetric-detection Time-stretch Optical Microscopy ATOM

This protocol describes the implementation of an asymmetric-detection time-stretch optical microscopy system for single-cell imaging in ultrafast microfluidic flow and its applications in imaging flow cytometry.

Cytométrie de flux d&#39;imagerie microfluidique par détection asymétrique Microscopie optique à temps-étirement (ATOM)

Scaling the number of measurable parameters, which allows for multidimensional data analysis and thus higher-confidence statistical results, has been the ...

Demonstration of a Hyperlens-integrated Microscope and Super-resolution Imaging

The use of super-resolution imaging to overcome the diffraction limit of conventional microscopy has attracted the interest of researchers in biology and nanotechnology. Although near-field scanning microscopy and superlenses have improved the resolution in the near-field region, far-field imaging in real-time remains a significant challenge. Recently, the hyperlens, which magnifies and converts evanescent waves into propagating waves, has emerged as a novel approach to far-field imaging. Here, we report the fabrication of a spherical hyperlens composed of alternating silver (Ag) and titanium oxide (TiO2) thin layers. Unlike a conventional cylindrical hyperlens, the spherical hyperlens allows for two-dimensional magnification. Thus, incorporation into conventional microscopy is straightforward. A new optical system integrated with the hyperlens is proposed, allowing for a sub-wavelength image to be obtained in the far-field region in real time. In this study, the fabrication and imaging setup methods are explained in detail. This work also describes the accessibility and possibility of the hyperlens, as well as practical applications of real-time imaging in living cells, which can lead to a revolution in biology and nanotechnology.

The use of a hyperlens has been regarded as a novel super-resolution imaging technique due to its advantages in real-time imaging and its simple implementation with conventional optics. Here, we present a protocol describing the fabrication and imaging applications of a spherical hyperlens.

Démonstration d’un Microscope intégré Hyperlens et Super-resolution Imaging

The use of super-resolution imaging to overcome the diffraction limit of conventional microscopy has attracted the interest of researchers in biology and ...

Multiplexing Focused Ultrasound Stimulation with Fluorescence Microscopy

By focusing low-intensity ultrasound pulses that penetrate soft tissues, LIPUS represents a promising biomedical technology to remotely and safely manipulate neural firing, hormonal secretion and genetically-reprogrammed cells. However, the translation of this technology for medical applications is currently hampered by a lack of biophysical mechanisms by which targeted tissues sense and respond to LIPUS. A suitable approach to identify these mechanisms would be to use optical biosensors in combination with LIPUS to determine underlying signaling pathways. However, implementing LIPUS to a fluorescence microscope may introduce undesired mechanical artefacts due to the presence of physical interfaces that reflect, absorb and refract acoustic waves. This article presents a step-by-step procedure to incorporate LIPUS to commercially-available upright epi-fluorescence microscopes while minimizing the influence of physical interfaces along the acoustic path. A simple procedure is described to operate a single-element ultrasound transducer and to bring the focal zone of the transducer into the objective focal point. The use of LIPUS is illustrated with an example of LIPUS-induced calcium transients in cultured human glioblastoma cells measured using calcium imaging.

Low-Intensity Pulsed Ultrasound Stimulation (LIPUS) is a modality for non-invasive mechanical stimulation of endogenous or engineered cells with high spatial and temporal resolution. This article describes how to implement LIPUS to an epi-fluorescence microscope and how to minimize acoustic impedance mismatch along the ultrasound path to prevent unwanted mechanical artefacts.

Multiplexage axé Stimulation ultrason avec la microscopie en Fluorescence

By focusing low-intensity ultrasound pulses that penetrate soft tissues, LIPUS represents a promising biomedical technology to remotely and safely ...

Measuring the Interaction Force Between a Droplet and a Super-hydrophobic Substrate by the Optical Lever Method

The goal of this paper is to investigate the interaction force between droplets and super-hydrophobic substrates in the air. A measurement system based on an optical lever method is designed. A millimetric cantilever is used as a force sensitive component in the measurement system. Firstly, the force sensitivity of the optical lever is calibrated using electrostatic force, which is the critical step in measuring interaction force. Secondly, three super-hydrophobic substrates with different grid fractions are prepared with nanoparticles and copper grids. Finally, the interaction forces between droplets and super-hydrophobic substrates with different grid fractions are measured by the system. This method can be used to measure the force on the scale of sub-micronewton with a resolution on the scale of nanonewton. The in-depth study of the contact process of droplets and super-hydrophobic structures can help to improve the production efficiency in coating, film and printing. The force measurement system designed in this paper can also be used in other fields of microforce measurement.

The protocol aims to investigate the interaction between droplets and super-hydrophobic substrates in the air. This includes calibrating the measurement system and measuring the interaction force at super-hydrophobic substrates with different grid fractions.

Mesurer la force d'interaction entre une gouttelette et un substrat super-hydrophobe selon la méthode du levier optique

The goal of this paper is to investigate the interaction force between droplets and super-hydrophobic substrates in the air. A measurement system based on ...

Design, Instrumentation and Usage Protocols for Distributed In Situ Thermal Hot Spots Monitoring in Electric Coils using FBG Sensor Multiplexing

Random wound coils are a key operational element of most electric apparatus in modern industrial systems, including low voltage electric machines. One of the major current bottlenecks in improved exploitation of electrical devices is the high sensitivity of their wound components to in-service thermal stress. The application of conventional thermal sensing methods (e.g., thermocouples, resistance temperature detectors) for thermal condition monitoring of current carrying random wound coils can impose considerable operational limitations due to sensor size, EMI sensitivity and the existence of electrically conductive material in their construction. Another substantial limitation exists in distributed sensing applications and is caused by what is often a considerable length and volume of conventional sensor wiring leads.
This paper reports the design of a fiber optic FBG&#160;sensing system&#160;intended for enabling real-time distributed internal thermal&#160;condition monitoring within random wound coils. The procedure of random wound coil instrumentation with the FBG sensing system is reported in a case study on an IEEE standard wound coil representative of those utilized in electrical machines. The reported work also presents and discusses important practical and technical aspects of FBG sensing system implementation and application, including the FBG array geometry design, sensing head and fiber packaging, the sensor array installation and calibration procedure and the use of a commercial interrogation system for obtaining thermal measurements. Finally, the in situ multiplexed FBG sensing system thermal monitoring performance is demonstrated in representative static and dynamic thermal conditions.&#160;

This paper presents a protocol that enables instrumentation of random wound electric coils with fiber Bragg grating (FBG) thermal sensors for the purpose of distributed condition monitoring of internal thermal hot spots.

Protocoles de conception, d’instrumentation et d’utilisation pour la surveillance des points chauds thermiques in situ distribués dans les bobines électriques à l’aide du multiplexe de capteur FBG

Random wound coils are a key operational element of most electric apparatus in modern industrial systems, including low voltage electric machines. One of ...