1. Setup-Alignment <ol><li> Starten von groben Ausrichten des Lasers, der Strahl expender, das Objektiv und die Kamera auf der gleichen Achse, dies würde die optische Achse sein. </li><li> Schalten Sie den Laser (ohne USAT Ziel), und stellen Sie sicher, dass das Licht durch das Zentrum der Linse passiert. Verwenden Sie eine Öffnung Iris zu überprüfen. </li><li> Schalten Sie die Kamera ein, und stellen Sie sicher, dass das Licht konzentriert sich auf die Mitte der Kamera. </li><li> Umschalttaste wieder die Kamera, mit der linearen z Bühne. Da das System unscharf gehen, wird der Lichtfleck zu wachsen. Sicherzustellen, dass die Mitte des Flecks bleibt in der gleichen Seitenposition. Wenn nicht, die Position des Abbildungssystems sorgfältig zu ändern, und wiederholen Sie diesen Schritt, bis der Fleck bleibt an der gleichen räumlichen Position bis zu einem Pixelebene. </li></ol> 2. Bildgebung bei Drei Unscharf Flugzeuge <ol><li> Legen Sie die Testziel vor dem Strahl expender. Platzieren Sie das Ziel, so dass das Licht, das durch sie hindurch passieren thrau die Mitte der Linse. </li><li> Aufnehmen eines Bildes. Dieses Bild wird ein Ankerpunkt sein, und seine Lage wird z 0 ist, x 0 (alle anderen Bilder werden in Bezug auf ihre Lage zu sein). Dieses Bild werde ich 1, b sein. </li><li> Rückverlagerung der Kamera (nach der linearen z Stufe) einen Abstand von dz = 5,08 mm (oder 0,2) und ein Bild aufzunehmen. Dieses Bild werde ich 2, b sein. </li><li> Rückverlagerung der Kamera einen anderen Abstand von dz = 5,08 mm (10,16 mm relativ zu z 0) und ein Bild aufzunehmen. Dieses Bild werde ich 3, b sein. </li><li> Gehen Sie zurück zu z 0. </li></ol> 3. Scannen der Blende <ol><li> Verschieben Sie den gesamten Imaging-System seitlich (unter Verwendung des linearen x Stufe) einen Abstand von dx = 2,5 mm und ein Bild aufzunehmen. Dieses Bild werde ich 1, a sein. </li><li> Wiederholen Sie den Vorgang in Protokoll Nr. 2. Rückverlagerung der Kamera (nach der linearen z-Stufe) ein Abstand von dz = 5,08 mm, und ein Bild aufzunehmen (I 2, a). Umschalt zurück the-Kamera ein anderer Abstand von dz = 5,08 mm, und erfassen ein Bild (I 3, a). </li><li> Jetzt wiederholen Sie den Vorgang für die andere Seite. Verschieben sich die Abbildungssystem einen Abstand von dx = -2,5 mm und erfassen eine Reihe von drei Bildern in drei z-Positionen (I 1-3, c). </li><li> Gehen Sie zurück zu z 0, x 0. </li></ol> 4. Phase-Retrieval (numerische Berechnung) <ol><li> Verwendung des Verfahrens drei Ebenen 14 und 1-3 Bilder I, B, Abrufen der optischen Phase des Bildes I 1, b. Verwendung der Phase, die abgerufen wurde, definiert q 1, b. </li><li> Überwachung der Korrelationskoeffizient zwischen I 1 und b | q 1, b | 2, um zu überprüfen, dass der iterative Prozess konvergiert. Um dies zu tun, benutzen Sie die &quot;corr2&quot;-Funktion in MATLAB. </li><li> Wiederholen Sie den Abrufprozess für Phase I 3.1, einer, und ich 03.01, c. </li></ol> 5. Super-Resolved Bild (numerische Berechnung) <ol><li> Usingen Fresnel Freiraumausbreitung (FSP) Integral 15, zurück in die Objektivebene propagieren die Felder q 1, ac. Diese Felder werden Ê Objektiv, ac + sein. </li><li> Multiplizieren Sie die resultierenden Felder Ê Objektiv, ac + exp (+ πix 0 2) / &amp;lgr; f), um wieder durch die Linse gehen. - Diese Felder werden Ê Objektiv, Wechsel sein. </li><li> Um das Feld E-Linse zu platzieren, ein in seiner ursprünglichen Position, verschieben sie seitlich einen Abstand von dx = 2,5 mm. </li><li> Um das Feld E-Objektiv in seine ursprüngliche Position zu bringen, c, verschieben sie seitlich einen Abstand von dx = -2,5 mm. </li><li> Addieren Sie die drei Felder Ê Objektiv, ac, um sie zu kombinieren und synthetisch erhöhen die Blendengröße. </li><li> Multiplizieren Sie das resultierende Feld von exp (-πix 0 2) / &amp;lgr; f) und freien Raum ausbreiten es um Bildebene. </li><li> Eine Verbesserung der Auflösung um einen Faktor of 3 in der Abtastrichtung sollte gesehen werden. </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>

Es gibt nichts zu offenbaren.

Die optische Radar mit synthetischer Apertur (OSAR) Konzept, das in diesem Papier vorgestellt wird, ist ein neues Super gelöst Ansatz, der die GS-Algorithmus und Scanning-Technik, um die Ortsauflösung eines Objekts in Richtung des Scans verbessern verwendet. Die Bewegung des Imaging-Plattform können selbst erzeugten während der Verwendung einer Luft-oder Satellitenplattform sein. Im Gegensatz zu vielen Zeitmultiplextechniken SR, unser Verfahren erfordert keine a priori-Informationen von dem Objekt, außer d...

In Radarbildgebung wird ein Schmalwinkel-Strahls von Hochfrequenzimpuls (RF) mit einer Antenne, die auf einer Plattform montiert ist, übertragen. Das Radarsignal überträgt in einer Seitensicht-Richtung auf der Oberfläche 1,2. Das reflektierte Signal wird von der Oberfläche zurückgestreute und durch dieselbe Antenne 2 empfangen. Die empfangenen Signale werden an einen Radar-Bild umgewandelt. In Echt Aperture Radar (RAR) die Auflösung in der Azimutrichtung ist proportional zur Wellenlänge und umgekehrt proportional zur Abmessung der Öffnung 3. Somit wird eine größere Antenne für höhere Winkelauflösung erforderlich. Es ist jedoch schwierig, große Antenne an einen beweglichen Plattformen wie Flugzeugen und Satelliten zu befestigen. Im Jahr 1951 Wiley 4 schlug eine neue Radar-Technik namens Synthetic Aperture Radar (SAR), die die Doppler-Effekt, der durch die Bewegung des Imaging-Plattform nutzt. SAR, die Amplitude als auch die Phase des empfangenen Signals aufgezeichnet 5 </sup&gt;. Dies ist möglich, da die SAR optischen Frequenz etwa 1-100 GHz 6 und die Phase wird mit einem lokalen Referenz Resonator auf der Oberseite der Plattform installiert aufgezeichnet. In optischen Abbildungs, kürzere Wellenlängen verwendet werden, wie im sichtbaren und im nahen Infrarot (NIR), die etwa 1 um ist, dh Frequenz von etwa 10 14 Hz ist. Die Feldstärke und nicht das Feld selbst, wird, da die optischen Phasenänderungen zu schnell für den Nachweis unter Verwendung von Standardsiliziumdetektoren detektiert. Beim Abbilden eines Objekts durch ein optisches System dient die Öffnung der Optik, wie ein Tiefpassfilter. Somit wird die Hochfrequenzraumdaten des Objekts 7 verloren. In diesem Papier wollen wir jedes der oben genannten Probleme einzeln zu lösen, dh die Phase verloren, und die Beugungsgrenze Wirkung. Gerchberg und Saxton (GS) 8 vorgeschlagen, dass die optische Phase kann Retrie werdenved Verwendung eines iterativen Prozesses. Misell 9-11 wurde der Algorithmus für jede zwei Eingangs-und Ausgangsebenen erweitert. Diese Ansätze sind nachweislich zu einer Phasenverteilung mit einem minimalen mittleren quadratischen Fehler (MSE) 12,13 konvergieren. Gur und Zalevsky 14 präsentierte drei Ebenen Methode, die die Misell Algorithmus verbessert. Wir schlagen vor, und zeigen, dass die Wiederherstellung experimentell die Phase, während Verschiebung der Abbildungslinse, wie mit der Antenne in SAR-Anwendung durchgeführt ermöglicht es uns, synthetisch erhöhen die effektive Größe der Öffnung entlang der Bewegungsachse und schließlich führte die Verbesserung der Bildauflösung. Die Anwendung der SAR-Bilderzeugung unter Verwendung der optischen Interferometrie und Holographie bekannt 16,17. Jedoch wird das vorgeschlagene Verfahren zum Nachahmen eines abtastenden bildgebenden Plattform, so dass es für die nicht-kohärente Tomographie (wie Seitenschau fliegende Plattform) geeignet ausgerichtet. So ist das Konzept der Holographie, welch verwendet einen Referenzstrahl, ist nicht geeignet für eine solche Anwendung. Stattdessen wird die überarbeitete Gerchberg-Saxton-Algorithmus verwendet, um die Phase abrufen.

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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>
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		<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>
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		<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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			<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>
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			<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>
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			<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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			<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>
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		<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>
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			<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

Wir schlagen ein Verfahren zur Erhöhung der Auflösung eines Objekts und die Überwindung der Beugungsgrenze des optischen Systems auf einer sich bewegenden Bilderzeugungssystem, wie einem Luft-oder Satellitenplattform installiert. Die Auflösungsverbesserung in einem zweistufigen Verfahren erhalten. Zunächst drei niedrige Auflösung unterschiedlich different Bilder werden erfasst und die optische Phase wird mit einer verbesserten iterative Gerchberg Saxton-basierten Algorithmus abgerufen. Die Phase Abruf ermöglicht, um das Feld auf die Öffnungsebene numerisch wieder propagieren. Zweitens wird das Abbildungssystem verschoben, und der erste Schritt wird wiederholt. Die erhaltenen optischen Felder an der Öffnungsebene kombiniert und ein synthetisch erhöht Blende entlang der Bewegungsrichtung erzeugt, wodurch höhere Bildauflösung. Das Verfahren ähnelt einem bekannten Ansatz aus dem Mikrowellenbereich genannt Synthetic Aperture Radar (SAR), in dem die Antennengröße wird synthetisch auf der Plattform erhöhtAusbreitungsrichtung. Das vorgeschlagene Verfahren wird durch Laborversuch nachgewiesen.

<html> Ein Beispiel für die neun Aufnahmen (drei Defokussierung Bilder in drei seitlichen Positionen) ist in Abbildung 3 dargestellt. Ein Beispiel für die Konvergenz GS ist in Fig. 4 gezeigt. Der Korrelationskoeffizient für das zentrale Bild I 1 ist, b über 0,95, und der Korrelationskoeffizient für die Seiten Bilder I 1, A und I 1, c ist über 0,85 (vollständig numerische Simulation alle bestanden 0,99). <p class="jo...

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

Ein Verfahren zur Überwindung der optischen Beugungsgrenze dargestellt. Das Verfahren umfasst einen zweistufigen Prozess: optische Phasenwiedergewinnungs Verwendung iterativer Gerchberg-Saxton-Algorithmus und Abbildungssystem Verschiebung gefolgt von einer Wiederholung des ersten Schrittes. Ein synthetisch erhöht Blende entlang der Bewegungsrichtung erzeugt, was zu höheren Bildauflösung.

Zeit-Multiplexing-Technik für überauflösenden Imaging von einer beweglichen Plattform

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 Aufrufe.  Bar-Ilan University.  Ein Verfahren zur Überwindung der optischen Beugungsgrenze dargestellt. Das Verfahren umfasst einen zweistufigen Prozess: optische Phasenwiedergewinnungs Verwendung iterativer Gerchberg-Saxton-Algorithmus und Abbildungssystem Verschiebung gefolgt von einer Wiederholung des ersten Schrittes. Ein synthetisch erhöht Blende entlang der Bewegungsrichtung erzeugt, was zu höheren Bildauflösung. 

Serie: 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.

Visualisierung von High-Speed-Flüssigkeitsstrahl-Impaction auf einer sich bewegenden Oberfläche

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

Forschung

Ingenieurwesen

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.

Die Messung der Streunichtlinearitäten von einem Einzel Plasmonische Nanopartikel

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.

Die Verwendung eines Mehrfach Dynamische einzelner Enzym-Phantom für Studien von hyperpolarisiertem Magnetic Resonance Agents

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.

Ein Hochleistungs-Impedanz-basierte Plattform für die Verdampfungsrate Erkennung

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;).

Ein Roboter-Plattform die Foreflipper des California Sea Lion zu studieren

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.

Mikrofluidische Imaging-Durchflusszytometrie durch asymmetrische Detektion Zeitstreck-Optische Mikroskopie (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.

Demonstration eines Hyperlens integriert Mikroskop und 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.

Multiplexen fokussiert Ultraschall-Stimulation mit Fluoreszenz-Mikroskopie

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.

Messung der Wechselwirkungskraft zwischen einem Tröpfchen und einem superhydrophoben Substrat durch die Optische Hebelmethode

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.

Design-, Instrumentierungs- und Nutzungsprotokolle für verteilte in Situ-Thermal-Hot Spots-Überwachung in elektrischen Spulen mit FBG-Sensormultiplexing

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