資金はユタ大学によって提供されました。我々は有益な議論のために博士J.徐（UCマーセド）博士BJNレディ（UCアーバイン）に感謝したいと思います。

1。 980nmの波長シングル光学トラップの設置<ol><li> 980nmの波長における光トラッピングは、多くの場合、生物物理学実験で安価なレーザダイオードに最適な300 mWのような高い電力出力で容易に入手可能である。これは、公知のモードフィールド径を有する偏波面保存シングルモードファイバピグテールとするダイオードレーザが好ましい。繊維は、モードフィルタとして機能する十分な長さが必要であり、一般的にFC / PCまたはFC / APCコネクタのどちらかで終了します。これらのうち、FC / APC光と潜在的なフィードバックの不安定性の反射を最小限に抑えるバックすることが好ましい。 </li><li>電力と温度制御を可能にするマウントで980 nmのレーザダイオードを固定します。受動的な放熱を最大化することにより、温度調節器の故障に起因するダイオード障害の危険性を最小限に抑えるために、直接光学テーブルにマウントを固定することをお勧めします。 </li><li>光学コリメートビームにPC / APCファイバコネクタを取り付けます。それは調節可能な光ファイバポートが最も有用であるので、平行ビームは、最小限の発散を持っていることを保証することが重要。選択された光ファイバポートは、ダイオードピグテールファイバのモードフィールド径と一致することを確認する。ビームは音響光学偏向器（AOD）又は電気光学偏向素子を用いてラスターする場合（EOD）はコリメートレーザビームウエストはまた、デフレクタ開口の大きさよりも僅かに小さくなければならない。 </li><li>ビームルーティング、拡張、および他の所望のコンポーネントの配置を可能にするために、顕微鏡から十分な距離を置いて光学テーブルへコリメートアダプターを固定します。顕微鏡への全体的なビーム経路に匹敵する距離で一貫性のあるビームウエストを確保するためのファイバーポートを調整します。 </li><li> 図1に示されているミラーを取り付けます。顕微鏡から目的を削除し、客観的な取り付けの段階で開口を通してルートにビームをミラーを使用しています。望ましい場合には、ダイクロイックミラーDM1とDM3の配置はまで省略することができます後で。 DM2とDM3はショートパスの両方であり、IRに近く、上記反射する可視光を透過する。 </li><li>一時的に顕微鏡の光軸上に整列目的の代わりに赤色レーザーポインタを、マウントすると便利です。カスタムメカニカルアダプタは、レーザーポインタのセンタリングを確保することが必要である。レーザーポインタからの可視光は、その後ファイバーポートの開口部の中央に戻ってルーティングすることができ、その後レンズを（下記参照）をインストールするために使用することができます。 </li><li>必要に応じて1としてステアリングコンポーネント（AODまたはEOD）の将来の挿入を可能にする光ファイバポートから適切な距離で980 nmのビームエキスパンダー（L8とL9）をインストールします。拡大ビームは、わずかに目標の後焦点絞りを入れすぎなければなりません。 （ここでは、125ミリメートルと60ミリメートルの焦点距離を持つレンズは約ビームウエストを倍増するためにケプラーの配置である。）適切なレンズ配置と粗いアラインメントを確保するために目に見えるレーザーポインタービーム（1.6節を参照）を使用します。 </li><li>インストール示された（ここで両方とも60ミリメートルの焦点距離を有する）1と望遠鏡配置lで980 nmの操舵レンズ（L2 ​​及びL3）。 L3は、対物レンズの後側焦平面に共役な面に取り付けられている。ビームステアリングを可能にする高精度XYZ位置決めステージ上にマウントL3。それは繰り返し位置決めとトラップの再配置を可能にする、そのためのマイクロデジタルインジケータを持つXYZステージのために有用です。 0.5 &quot;は、旅行の範囲は通常は十分ですが、光軸に沿ってL3の位置決めのためのより長い旅行が役に立つかもしれません。適切なレンズ配置と粗いアラインメントを確保するために目に見えるレーザーポインタービーム（1.6節を参照）を使用します。 </li></ol> 2。レーザー検出器の設置<ol><li> 図1に示すように、コンデンサ上記ダイクロイックミラーDM3をインストールする。カスタムマウントは、通常必要とされる。コンデンサーアセンブリの側面にクワッドフォトダイオード（QPD）や位置敏感型検出器（PSD）8を確保し、ENS980 nmのレーザービームがDM3によって反射することUREは大体中央にそれに当たっている。 QPDを使用する際には、レーザビームのセンサーの正確なセンタリングを可能にするにはXYステージ上に搭載されていることを確認する。 </li><li> DM3とセンサの間のL1を（通常は30 mmレンズ）をインストールします。センサー上の単一スポットにビームを集束するように位置は、L1。 </li><li> L1は顕微鏡照明と周囲の照明から1,064 nmのビームと同様の浮遊可視光の反射を遮断するために直前にノッチフィルタを取り付けます。 </li></ol> 3。 1,064 nmの波長ホログラフィトラップの設置<ol><li>セットアップのホログラフィックの部分は、このパッケージで使用されるホログラムミラーは5または10 W / cm 2での最大入射電力定格されている市販のハードウェア/ソフトウェアのパッケージを中心に構築されています。この電力範囲内の単一モードTEM00ビームは簡単に1,064 nmの波長でDPSSレーザーから供給することができます。 </li><li>高架上の1,064 nmレーザーをマウントプラットフォームは、およそ980ライン（第1参照）のビーム経路の高さを一致させる。 </li><li>直接制御できない場合は、レーザパワーを手動で右側のレーザ出力開口後の半波長板（HWP）と偏光子（PBS）をインストールすることによって調整することができる。これは、ビームの偏光のためのホログラムミラー要件に一致させることができるように回転ステージの偏光板を取り付けることが有用である。 </li><li> 1,064 nmのビームエキスパンダー（L6とL7）をインストールします。レーザービームウエストは、ホログラフィックミラーの対角サイズに合わせて拡大されている必要があります。大拡張比（10倍以上）のためには、小さなパンダの大きさを維持するために心配かもしれません。 （：16 mmであり、ここでは175ミリメートル）従って、異常に小さい焦点距離のレンズを使用することが望ましい場合がある。 </li><li>客観を通じて1,064 nmのビームを向けるように示されているように、他のミラーを取り付けます。 <ol><li>それはundiminishe可能になるようにセキュアDM1キネマティックマウントにおけるダイクロ（入射45°の角度）とは、980 nmの光路内にアセンブリを配置そのビームのD伝送。 </li><li>レーザーポインターの光をアクティブにします。 DM1ミラーが適切にこのビームの経路内に空間光変調器（SLM）を位置決めする可視光の量を十分に反映すべきである。 SLMは、着信および発信のレーザービームは、通常の発生率にできるだけ接近しているように、角度を付けする必要があります。しかし、入射角は、レーザビームがレンズマウント、および他の光学部品によってクリップされないように十分に大きくなければならない。 5°の角度が容易に達成されると十分に小さい必要があります。最後DM1からSLMまでの距離を正確にレンズL4とL5の挿入が（下記3.6を参照）SLM鏡面と客観のバック焦点面を活用できる​​ように、測定されなければならない。 </li><li> 1,064 nmのビームエキスパンダからSLMに光を導くためにミ​​ラーを取り付けます。レーザーポインターの光が中央にビームエキスパンダー開口に当たることを確認してください。 </li></ol></li><li> L4とL5レンズを取り付けます（ここでは12のレンズそれぞれ5mmで200ミリメートル）。この望遠鏡のペアは、対物レンズの後焦点面にSLM鏡面をコンジュゲートし、また少しだけ入れ過ぎに目的の背面開口部をビームウエストを減らすことができます。私たちは、SLM離れDM1から空間に長い焦点距離のレンズを選んだ。これにより、第2のレーザ線の余地をクリアしなくアライメントを容易にする傾向があるのみならず。 </li><li>レーザーポインタを削除します。粗いアラインメント絞りとして機能するようにマウントアダプタにしておきます。 </li></ol> 4。システムのインストールとアライメント注意<ol><li>目的の後焦点面と光学的に共役になるようレンズL3とSLMがように配置しなければなりません。光トラッピングビームが顕微鏡の無限大の空間に注入される場合、L4とL5の共通の焦点が試料面に光学的に結合している。 </li><li>歌うIRカードビューアはレーザーポインターのアダプタの開口部の中心軸に沿って移動する980 nmの光を合わせます。 </li><li> IRカードTを使用して、oが1,064 nmのビームはDM1、L2、およびL3上と1,064 nmのビームはレーザーポインターのアダプタの開口部の中心軸に沿って行くことを980 nmのビームと同じスポットに当たることを確認してください。 </li><li>を目的としたレーザーポインターマウントアダプターを交換します。高開口数の対物油または水が典型的である。 </li><li>レーザービームを&quot;歩く&quot;ことで9で説明したように放射状に対称の干渉パターンをカメラで見られるまで980 nmのトラップの位置を合わせます。 </li><li>ホログラフィックミラーをオフにして（ つまり、受動的ミラーとして機能）1,064 nmのトラップを整列させる非回折1,064 nmの光を&quot;歩く&quot;ためにSLMとDM1を使用しています。 </li><li> SLMは、視野内の強い不動レーザートラップをもたらす重要な非回折ビームを生成する。これは、位置合わせのために有用であるが、実験のために望ましくないかもしれません。このトラップをブロックするには一つ（試料面に位置共役な非回折光の経路に小さな不透明なオブジェクトを挿入することができます例えば番目L4とL5）のE共通の焦点。この中央のスポットブロッカーが集光された光（記載されているシステムのための100-300ミクロン径のブロッカー）のためのエアリーディスクの直径よりも若干大きくする必要があるのサイズ。 </li><li> SLMの向きを一致させる偏光子を用いた1,064 nmのビームの偏光をdjust。所望に応じて光の出力パワーを設定する半波長板を回転させる。 </li><li>必要に応じて、980 nmのレーザー線にAOD又はEODビームステアリング要素を挿入。目的のバックフォーカルプレーンにこれらの要素の適切な共役を確保し、トラップを再調整。ゴニオステージ上ステアリング要素をマウントすると便利です。 </li></ol>

<ol>
	<li>Svoboda, K., Block, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Biological+applications+of+optical+forces.">Biological applications of optical forces.</a> Annu. Rev. Biophys. Biomol. Struct. 23, 247-285 (1994).</li><li>Ashkin, A., Schutze, K., Dziedzic, J. M., Euteneuer, U., Schliwa, M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Force+generation+of+organelle+transport+measured+in+vivo+by+an+infrared+laser+trap.">Force generation of organelle transport measured in vivo by an infrared laser trap.</a> Nature. 348, 346-348 (1990).</li><li>Shubeita, G. T., Tran, S. L., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Consequences+of+motor+copy+number+on+the+intracellular+transport+of+kinesin-1-driven+lipid+droplets.">Consequences of motor copy number on the intracellular transport of kinesin-1-driven lipid droplets.</a> Cell. 135, 1098-1107 (2008).</li><li>Polin, M., Ladavac, K., Lee, S. H., Roichman, Y., Grier, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optimized+holographic+optical+traps.">Optimized holographic optical traps.</a> Opt Express. 13, 5831-5845 (2005).</li><li>Sun, B., Roichman, Y., Grier, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Theory+of+holographic+optical+trapping.">Theory of holographic optical trapping.</a> Opt. Express. 16, 15765-15776 (2008).</li><li>Moffitt, J. R., Chemla, Y. R., Smith, S. B., Bustamante, C. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Recent+advances+in+optical+tweezers.">Recent advances in optical tweezers.</a> Annu. Rev. Biochem. 77, 205-228 (2008).</li><li>Grier, D. G. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+revolution+in+optical+manipulation.">A revolution in optical manipulation.</a> Nature. 424, 810-816 (2003).</li><li>Neuman, K. C., Block, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+trapping.">Optical trapping.</a> Rev. Sci. Instrum. 75, 2787-2809 (2004).</li><li>Sheetz, M. P. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Laser+tweezers+in+cell+biology.">Laser tweezers in cell biology.</a> Introduction. Methods Cell Biol. 55, xi-xii (1998).</li><li>Spudich, J. A., Rice, S. E., Rock, R. S., Purcell, T. J., Warrick, H. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Optical+traps+to+study+properties+of+molecular+motors.">Optical traps to study properties of molecular motors.</a> Cold Spring Harb. Protoc. 2011, 1305-1318 (2011).</li><li>Visscher, K., Gross, S. P., Block, S. M. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Construction+of+multiple-beam+optical+traps+with+nanometer-resolution+position+sensing.+Selected+Topics+in+Quantum+Electronics.">Construction of multiple-beam optical traps with nanometer-resolution position sensing. Selected Topics in Quantum Electronics.</a> IEEE Journal of. 2, 1066-1076 (1996).</li><li>Valentine, M. T., Guydosh, N. R., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Precision+steering+of+an+optical+trap+by+electro-optic+deflection.">Precision steering of an optical trap by electro-optic deflection.</a> Opt Lett. 33, 599-601 (2008).</li></ol>

著者らは、開示することは何もありません。

我々は、オブジェクトの操作および測定するための別々の捕捉機能を提供する異なるタイプ（ 図1）の二つの光学トラップを組み合わせた器具を構築した。 &quot;従来&quot;光学トラップは980 nmのダイオードレーザーを中心に構築されています。このビームは、拡大して操縦した後（ 図1の&quot;光赤&quot;ビーム）当社の倒立顕微鏡に注入される。ホログラフィック光学ト?...

光トラッピングは、生物物理学6における主要技術の一つである。光トラッピングに重要な進歩は、三次元の捕獲パターンではなく、従来のポイントトラップ7の作成 ​​を可能にするホログラフィックトラップの開発をされています。このようなホログラフィックトラップは屈折オブジェクトの位置で汎用性の利点を持っています。しかし従来のトラップは簡単に市販のホログラフィックキットよりも対称に整列させることができる。彼らはまた、閉じ込められたオブジェクトの迅速正確なトラッキングを可能にします。ここではひとつの楽器で2トラッピングのアプローチを組み合わせて、ユーザーが必要に応じて両方の利点を活用できるようにするシステム（ 図1）について説明します。 構築光学トラップ（単一または複数のレーザービームに基づく）の一般的な考察は別の場所8-10詳細に議論されています。ここで、私たちはsに固有の考慮事項を概説etupと当社アライメント手順の詳細を提供。例えば、2つの光トラッピングビームを有するシステムは、典型的には、屈折物体を捕捉し、捕捉された物体の位置のデカップリング読出しのために（意図的に低電力ビーム）その他を使用するための1つのレーザビームを用いて、（ 例えば、参考文献11）の前に記載されている。ここしかしながら、両方のレーザビームは、両方の捕捉のために使用されるので（300 MWまたはより高い）動力高くする必要がある。生物系の測定では、トラッピングのため使用されるレーザーは、最適に光誘発タンパク質分解1を最小化するために波長の特定のNIRウィンドウ内に収まる必要があります。ここでは、980 nmのダイオードとするため、低コスト、高可用性と操作のしやすさの1,064 nmのDPSSレーザーを使用することを選択しました。 また、4,5、リアルタイムで同時に複数のトラップを作成し、操作する空間光変調器（SLM）を使用することを選択した。これらの装置は市販されているしかし完全なセットアップへの統合は、ユニークな課題を提示。ここでは、これらの潜在的な困難に対処し、汎用性の高い楽器を提供する実用的なアプローチを説明する。我々は、変更された設計のためのガイドとして使用することができる具体的なセットアップのための明示的な例を提供します。

<table border="1">
	<tbody>
		<tr>
			<td>Equipment</td>
			<td>Company</td>
			<td>Catalog Number</td>
			<td>Comments</td>
		</tr>
		<tr>
			<td>Optical table</td>
			<td>Newport corporation</td>
			<td>ST-UT2-56-8</td>
			<td>Irvine, CA</td>
		</tr>
		<tr>
			<td>Microscope, Inverted, Eclipse Ti</td>
			<td>Nikon USA</td>
			<td>MEA53220</td>
			<td>Melville, NY</td>
		</tr>
		<tr>
			<td>Plan apo 100X oil objective (1.4 NA)</td>
			<td>Nikon USA</td>
			<td>MRD01901</td>
			<td>Melville, NY</td>
		</tr>
		<tr>
			<td>Oil condenser Lens 1.4 NA</td>
			<td>Nikon USA</td>
			<td>MEL41410</td>
			<td>Melville, NY</td>
		</tr>
		<tr>
			<td>EMCCD camera</td>
			<td>Andor technology USA</td>
			<td>Ixon DU897</td>
			<td>South Windsor, CT</td>
		</tr>
		<tr>
			<td>1/3" CCD IEEE1394 camera</td>
			<td>NET USA Inc</td>
			<td>Foculus FO124SC</td>
			<td>Highland IN</td>
		</tr>
		<tr>
			<td>Laser, TEM00, SLM, 1,064 nm wavelength</td>
			<td>Klastech Laser Technologies</td>
			<td>Senza-1064-1000</td>
			<td>Dortmund; Germany</td>
		</tr>
		<tr>
			<td>laser diode, TEM00, SLM, 980 nm</td>
			<td>Axcel Photonics</td>
			<td>BF-979-0300-P5A</td>
			<td>Marlborough, MA</td>
		</tr>
		<tr>
			<td>laser diode mount</td>
			<td>ILX Lightwave</td>
			<td>LDX-3545, LDT-5525, and LDM-4984</td>
			<td>Bozeman, MT</td>
		</tr>
		<tr>
			<td>adjustable fiber ports</td>
			<td>Thorlabs</td>
			<td>PAF-X-11-B</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>holographic system</td>
			<td>Arryx</td>
			<td>HOTKIT-ADV-1064</td>
			<td>Chicago, IL</td>
		</tr>
		<tr>
			<td>holographic mirror</td>
			<td>Boulder Non-linear Systems</td>
			<td>this is a part of HOTKIT-ADV-1064</td>
			<td>Lafayette, CO</td>
		</tr>
		<tr>
			<td>Calcite polarizer</td>
			<td>Thorlabs</td>
			<td>GL10-B</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>half-wave plate</td>
			<td>Thorlabs</td>
			<td>WPH05M-1064</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>Polarizer rotation mount</td>
			<td>Thorlabs</td>
			<td>PRM1</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>half-wave plate rotation mount</td>
			<td>Thorlabs</td>
			<td>RSP1</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>Shutter</td>
			<td>Thorlabs</td>
			<td>SH05</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>dichroic mirrors (DM2 &amp; DM3); 45&deg; AOI</td>
			<td>Chroma Technology</td>
			<td>t750spxrxt</td>
			<td>Bellows Falls, VT</td>
		</tr>
		<tr>
			<td>dichroic mirror (DM1); 45&deg; AOI</td>
			<td>Thorlabs</td>
			<td>DMSP1000R</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>custom mechanical adapter</td>
			<td>Thorlabs</td>
			<td>SM1A11 and AD12F with enlarged inner bore</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>notch filter</td>
			<td>Semrock</td>
			<td>FF01-850/310-25</td>
			<td>Rochester, NY</td>
		</tr>
		<tr>
			<td>Acousto-Optic deflector (2-axis)</td>
			<td>intraAction</td>
			<td>DTD-584CA28</td>
			<td>Bellwood, IL</td>
		</tr>
		<tr>
			<td>goniometric stage</td>
			<td>New Focus</td>
			<td>9081</td>
			<td>Santa Clara, CA</td>
		</tr>
		<tr>
			<td>60 mm steering lenses</td>
			<td>Thorlabs</td>
			<td>LA1134-B</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>16 mm aspherical expander lens</td>
			<td>Thorlabs</td>
			<td>AC080-016-C</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>175 mm expander lens</td>
			<td>Thorlabs</td>
			<td>LA1229-C</td>
			<td>Newton, NJ</td>
		</tr>
		<tr>
			<td>Spot blocker (cabron-steel sphere)</td>
			<td>Bal-Tec</td>
			<td>0.0100" diameter</td>
			<td>Los Angeles, CA</td>
		</tr>
		<tr>
			<td>Microspheres (Carboxyl-polystyrene)</td>
			<td>Spherotech</td>
			<td>CP-45-10</td>
			<td>Lake Forest, IL</td>
		</tr>
	</tbody>
</table>

construction of a high resolution microscope with conventional and holographic optical trapping capabilities

光学トラップの高解像度顕微鏡システムは、このような誘電ビーズ1または細胞小器官2,3と同様に、トラップの中心に対してそれらの位置の高空間分解能と時間分解能の読み出し用として、様々な屈折オブジェクトの正確な操作が可能になります。システムがここに980nmの1つのこのような &quot;伝統的な&quot;トラップ動作が持って説明。それはさらに、同時に波長1064nmにおける4,5顕微鏡の視野内に複雑なトラッピングパターンを作成し、操作するために、市販のホログラフィックパッケージを使用して第二の光学トラップシステムを提供する。同時に高速およびナノメートルスケールでのピコニュートン動作と力の生産高分解能測定を行いながら、2系統の組み合わせは、同時に複数の屈折オブジェクトの操作を可能にする。

組み立てられた設定は、オペレータがリアルタイムで複数の屈折オブジェクトをトラップし、視野内の全ての三次元的にそれらを配置することができる。我々は11マイクロスフェア（ 図2）トラップして楽器のホログラフィック機能を示す。各オブジェクトを閉じ込めるトラップは手動で、最終的な配置が、この実験を行ったユタ大学のロゴを示すように、トラッピング時に再び?...

Watch this Scientific Journal Video about Construction of a High Resolution Microscope with Conventional and Holographic Optical Trapping Capabilities at JoVE.com

Construction of a High Resolution Microscope with Conventional and Holographic Optical Trapping Capabilities

ここに記載されているシステムでは、複数のトラップを作成し、操作することのできる伝統的な光学トラップと同様に、独立したホログラフィック光トラッピングラインを採用。また、生物学的酵素活性の同時高速·高分解能な測定を可能にしつつ、屈折率粒子の複合幾何学的配置の作成を可能にする。

従来のホログラフィック光トラッピング機能を備えた高分解能顕微鏡の構成

High resolution microscope systems with optical traps allow for precise manipulation of various refractive objects, such as dielectric beads 1 or cellular ...

construction-high-resolution-microscope-with-conventional-holographic

Research

JoVE Journal

Engineering

12.1K ビュー.  University of Utah. ここに記載されているシステムでは、複数のトラップを作成し、操作することのできる伝統的な光学トラップと同様に、独立したホログラフィック光トラッピングラインを採用。また、生物学的酵素活性の同時高速·高分解能な測定を可能にしつつ、屈折率粒子の複合幾何学的配置の作成を可能にする。

ビデオ: Construction of a High Resolution Microscope with Conventional and Holographic Optical Trapping Capabilities

Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To compensate for lower light absorption such physically thin devices have to incorporate light-trapping which increases their optical thickness. Light scattering by textured surfaces is a common technique but it cannot be universally applied to all solar cell technologies. Some cells, for example those made of evaporated silicon, are planar as produced and they require an alternative light-trapping means suitable for planar devices. Metal nanoparticles formed on planar silicon cell surface and capable of light scattering due to surface plasmon resonance is an effective approach.
The paper presents a fabrication procedure of evaporated polycrystalline silicon solar cells with plasmonic light-trapping and demonstrates how the cell quantum efficiency improves due to presence of metal nanoparticles.
To fabricate the cells a film consisting of alternative boron and phosphorous doped silicon layers is deposited on glass substrate by electron beam evaporation. An Initially amorphous film is crystallised and electronic defects are mitigated by annealing and hydrogen passivation. Metal grid contacts are applied to the layers of opposite polarity to extract electricity generated by the cell. Typically, such a ~2 &mu;m thick cell has a short-circuit current density (Jsc) of 14-16 mA/cm2, which can be increased up to 17-18 mA/cm2 (~25% higher) after application of a simple diffuse back reflector made of a white paint.
To implement plasmonic light-trapping a silver nanoparticle array is formed on the metallised cell silicon surface. A precursor silver film is deposited on the cell by thermal evaporation and annealed at 23&deg;C to form silver nanoparticles. Nanoparticle size and coverage, which affect plasmonic light-scattering, can be tuned for enhanced cell performance by varying the precursor film thickness and its annealing conditions. An optimised nanoparticle array alone results in cell Jsc enhancement of about 28%, similar to the effect of the diffuse reflector. The photocurrent can be further increased by coating the nanoparticles by a low refractive index dielectric, like MgF2, and applying the diffused reflector. The complete plasmonic cell structure comprises the polycrystalline silicon film, a silver nanoparticle array, a layer of MgF2, and a diffuse reflector. The Jsc for such cell is 21-23 mA/cm2, up to 45% higher than Jsc of the original cell without light-trapping or ~25% higher than Jsc for the cell with the diffuse reflector only.
Introduction
Light-trapping in silicon solar cells is commonly achieved via light scattering at textured interfaces. Scattered light travels through a cell at oblique angles for a longer distance and when such angles exceed the critical angle at the cell interfaces the light is permanently trapped in the cell by total internal reflection (Animation 1: Light-trapping). Although this scheme works well for most solar cells, there are developing technologies where ultra-thin Si layers are produced planar (e.g. layer-transfer technologies and epitaxial c-Si layers) 1 and or when such layers are not compatible with textures substrates (e.g. evaporated silicon) 2. For such originally planar Si layer alternative light trapping approaches, such as diffuse white paint reflector 3, silicon plasma texturing 4 or high refractive index nanoparticle reflector 5 have been suggested.
Metal nanoparticles can effectively scatter incident light into a higher refractive index material, like silicon, due to the surface plasmon resonance effect 6. They also can be easily formed on the planar silicon cell surface thus offering a light-trapping approach alternative to texturing. For a nanoparticle located at the air-silicon interface the scattered light fraction coupled into silicon exceeds 95% and a large faction of that light is scattered at angles above critical providing nearly ideal light-trapping condition (Animation 2: Plasmons on NP). The resonance can be tuned to the wavelength region, which is most important for a particular cell material and design, by varying the nanoparticle average size, surface coverage and local dielectric environment 6,7. Theoretical design principles of plasmonic nanoparticle solar cells have been suggested 8. In practice, Ag nanoparticle array is an ideal light-trapping partner for poly-Si thin-film solar cells because most of these design principle are naturally met. The simplest way of forming nanoparticles by thermal annealing of a thin precursor Ag film results in a random array with a relatively wide size and shape distribution, which is particularly suitable for light-trapping because such an array has a wide resonance peak, covering the wavelength range of 700-900 nm, important for poly-Si solar cell performance. The nanoparticle array can only be located on the rear poly-Si cell surface thus avoiding destructive interference between incident and scattered light which occurs for front-located nanoparticles 9. Moreover, poly-Si thin-film cells do not requires a passivating layer and the flat base-shaped nanoparticles (that naturally result from thermal annealing of a metal film) can be directly placed on silicon further increases plasmonic scattering efficiency due to surface plasmon-polariton resonance 10.
The cell with the plasmonic nanoparticle array as described above can have a photocurrent about 28% higher than the original cell. However, the array still transmits a significant amount of light which escapes through the rear of the cell and does not contribute into the current. This loss can be mitigated by adding a rear reflector to allow catching transmitted light and re-directing it back to the cell. Providing sufficient distance between the reflector and the nanoparticles (a few hundred nanometers) the reflected light will then experience one more plasmonic scattering event while passing through the nanoparticle array on re-entering the cell and the reflector itself can be made diffuse - both effects further facilitating light scattering and hence light-trapping. Importantly, the Ag nanoparticles have to be encapsulated with an inert and low refractive index dielectric, like MgF2 or SiO2, from the rear reflector to avoid mechanical and chemical damage 7. Low refractive index for this cladding layer is required to maintain a high coupling fraction into silicon and larger scattering angles, which are ensured by the high optical contrast between the media on both sides of the nanoparticle, silicon and dielectric 6. The photocurrent of the plasmonic cell with the diffuse rear reflector can be up to 45% higher than the current of the original cell or up to 25% higher than the current of an equivalent cell with the diffuse reflector only.

Polycrystalline silicon thin-film solar cells on glass are fabricated by deposition of boron and phosphorous doped silicon layers followed by crystallisation, defect passivation and metallisation. Plasmonic light-trapping is introduced by forming Ag nanoparticles on the silicon cell surface capped with a diffused reflector resulting in ~45% photocurrent enhancement.

プラズモニック·強化されたライトトラップによる多結晶シリコン薄膜太陽電池

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To ...

工学

Construction and Testing of Coin Cells of Lithium Ion Batteries

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime. Lithium ion batteries have also been considered to be used in electric and hybrid vehicles1 or even electrical grid stabilization systems2. All these applications simulate a dramatic increase in the research and development of battery materials3-7, including new materials3,8, doping9, nanostructuring10-13, coatings or surface modifications14-17 and novel binders18. Consequently, an increasing number of physicists, chemists and materials scientists have recently ventured into this area. Coin cells are widely used in research laboratories to test new battery materials; even for the research and development that target large-scale and high-power applications, small coin cells are often used to test the capacities and rate capabilities of new materials in the initial stage. 
 In 2010, we started a National Science Foundation (NSF) sponsored research project to investigate the surface adsorption and disordering in battery materials (grant no. DMR-1006515). In the initial stage of this project, we have struggled to learn the techniques of assembling and testing coin cells, which cannot be achieved without numerous help of other researchers in other universities (through frequent calls, email exchanges and two site visits). Thus, we feel that it is beneficial to document, by both text and video, a protocol of assembling and testing a coin cell, which will help other new researchers in this field. This effort represents the "Broader Impact" activities of our NSF project, and it will also help to educate and inspire students.
In this video article, we document a protocol to assemble a CR2032 coin cell with a LiCoO2 working electrode, a Li counter electrode, and (the mostly commonly used) polyvinylidene fluoride (PVDF) binder. To ensure new learners to readily repeat the protocol, we keep the protocol as specific and explicit as we can. However, it is important to note that in specific research and development work, many parameters adopted here can be varied. First, one can make coin cells of different sizes and test the working electrode against a counter electrode other than Li. Second, the amounts of C black and binder added into the working electrodes are often varied to suit the particular purpose of research; for example, large amounts of C black or even inert powder were added to the working electrode to test the "intrinsic" performance of cathode materials14. Third, better binders (other than PVDF) have also developed and used18. Finally, other types of electrolytes (instead of LiPF6) can also be used; in fact, certain high-voltage electrode materials will require the uses of special electrolytes7.

A protocol to construct and test coin cells of lithium ion batteries is described. The specific procedures of making a working electrode, preparing a counter electrode, assembling a cell inside a glovebox and testing the cell are presented.

リチウムイオン電池のコイン細胞の構築とテスト

Rechargeable lithium ion batteries have wide applications in electronics, where customers always demand more capacity and longer lifetime.  Lithium ion ...

Optical Trapping of Nanoparticles

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping and manipulating small biological particles. Ashkin and co-workers first demonstrated optical tweezers using a single focused beam1. The single beam trap can be described accurately using the perturbative gradient force formulation in the case of small Rayleigh regime particles1. In the perturbative regime, the optical power required for trapping a particle scales as the inverse fourth power of the particle size. High optical powers can damage dielectric particles and cause heating. For instance, trapped latex spheres of 109 nm in diameter were destroyed by a 15 mW beam in 25 sec1, which has serious implications for biological matter2,3.
A self-induced back-action (SIBA) optical trapping was proposed to trap 50 nm polystyrene spheres in the non-perturbative regime4. In a non-perturbative regime, even a small particle with little permittivity contrast to the background can influence significantly the ambient electromagnetic field and induce a large optical force. As a particle enters an illuminated aperture, light transmission increases dramatically because of dielectric loading. If the particle attempts to leave the aperture, decreased transmission causes a change in momentum outwards from the hole and, by Newton's Third Law, results in a force on the particle inwards into the hole, trapping the particle. The light transmission can be monitored; hence, the trap can become a sensor. The SIBA trapping technique can be further improved by using a double-nanohole structure.
The double-nanohole structure has been shown to give a strong local field enhancement5,6. Between the two sharp tips of the double-nanohole, a small particle can cause a large change in optical transmission, thereby inducing a large optical force. As a result, smaller nanoparticles can be trapped, such as 12 nm silicate spheres7 and 3.4 nm hydrodynamic radius bovine serum albumin proteins8. In this work, the experimental configuration used for nanoparticle trapping is outlined. First, we detail the assembly of the trapping setup which is based on a Thorlabs Optical Tweezer Kit. Next, we explain the nanofabrication procedure of the double-nanohole in a metal film, the fabrication of the microfluidic chamber and the sample preparation. Finally, we detail the data acquisition procedure and provide typical results for trapping 20 nm polystyrene nanospheres.

The following setup approach details low power optical trapping of dielectric nanoparticles using a double-nanohole in metal film.

ナノ粒子の光トラッピング

Optical trapping is a technique for immobilizing and manipulating small objects in a gentle way using light, and it has been widely applied in trapping ...

High-resolution, High-speed, Three-dimensional Video Imaging with Digital Fringe Projection Techniques

Digital fringe projection (DFP) techniques provide dense 3D measurements of dynamically changing surfaces.&#160;Like the human eyes and brain, DFP uses triangulation between matching points in two views of the same scene at different angles to compute depth.&#160;However, unlike a stereo-based method, DFP uses a digital video projector to replace one of the cameras1. The projector rapidly projects a known sinusoidal pattern onto the subject, and the surface of the subject distorts these patterns in the camera&#8217;s field of view. Three distorted patterns (fringe images) from the camera can be used to compute the depth using triangulation.
Unlike other 3D measurement methods, DFP techniques lead to systems that tend to be faster, lower in equipment cost, more flexible, and easier to develop.&#160;DFP systems can also achieve the same measurement resolution as the camera.&#160;For this reason, DFP and other digital structured light techniques have recently been the focus of intense research (as summarized in1-5). Taking advantage of DFP, the graphics processing unit, and optimized algorithms, we have developed a system capable of 30&#160;Hz 3D video data acquisition, reconstruction, and display for over 300,000 measurement points per frame6,7.&#160;Binary defocusing DFP methods can achieve even greater speeds8.
Diverse applications can benefit from DFP techniques. Our collaborators have used our systems for facial function analysis9, facial animation10, cardiac mechanics studies11, and fluid surface measurements, but many other potential applications exist.&#160;This video will teach the fundamentals of DFP techniques and illustrate the design and operation of a binary defocusing DFP system.

This video describes the fundamentals of digital fringe projection techniques, which provide dense 3D measurements of dynamically changing surfaces.&#160;It also demonstrates the design and operation of a high-speed binary defocusing system based on these techniques.

デジタル干渉縞投影技術と高分解能、高速、三次元ビデオ画像

Digital fringe projection (DFP) techniques provide dense 3D measurements of dynamically changing surfaces.&#160;Like the human eyes and brain, DFP uses ...

Compact Lens-less Digital Holographic Microscope for MEMS Inspection and Characterization

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and automotive. However, effective inspection and characterization metrology systems are needed to ensure the functional reliability of MEMS. This study presents a system based on digital holography as a tool for MEMS metrology. Digital holography has gained increasing attention in the past 20 years. With the fast development and decreasing cost of sensor arrays, resolution of such systems has increased broadening potential applications. Thus, it has attracted attention from both research and industry sides as a potential reliable tool for industrial metrology. Indeed, by recording the interference pattern between an object beam (which contains sample height information) and a reference beam on a CCD camera, one can retrieve the quantitative phase information of an object. However, most of digital holographic systems are bulky and thus not easy to implement on industry production lines. The novelty of the system presented is that it is lens-less and thus very compact. In this study, it is shown that the Compact Digital Holographic Microscope (CDHM) can be used to evaluate several characteristics typically consider as criteria in MEMS inspections. The surface profiles of MEMS in both static and dynamic conditions are presented. Comparison with AFM is investigated to validate the accuracy of the CDHM.

We present a compact reflection digital holographic system (CDHM) for inspection and characterization of MEMS devices. A lens-less design using a diverging input wave providing natural geometrical magnification is demonstrated. Both static and dynamic studies are presented.

MEMS検査および特性評価のためのコンパクトなレンズレスデジタルホログラフィック顕微鏡

A micro-electro-mechanical-system (MEMS) is a widely used component in many industries, including energy, biotechnology, medical, communications, and ...

High Resolution Phonon-assisted Quasi-resonance Fluorescence Spectroscopy

High resolution optical spectroscopy methods are demanding in terms of either technology, equipment, complexity, time or a combination of these. Here we demonstrate an optical spectroscopy method that is capable of resolving spectral features beyond that of the spin fine structure and homogeneous linewidth of single quantum dots (QDs) using a standard, easy-to-use spectrometer setup. This method incorporates both laser and photoluminescence spectroscopy, combining the advantage of laser line-width limited resolution with multi-channel photoluminescence detection. Such a scheme allows for considerable improvement of resolution over that of a common single-stage spectrometer. The method uses phonons to assist in the measurement of the photoluminescence of a single quantum dot after resonant excitation of its ground state transition. The phonon&#39;s energy difference allows one to separate and filter out the laser light exciting the quantum dot. An advantageous feature of this method is its straight forward integration into standard spectroscopy setups, which are accessible to most researchers.

The manuscript describes a method of phonon-assisted quasi-resonant fluorescence spectroscopy that incorporates both laser-limited resolution and photoluminescence (PL) spectroscopy. This method utilizes optical phonons to provide linewidth-limited resolution spectra of atom-like semiconductor structures in the energy domain. The method is also easily realized with a single spectrometer optical spectroscopy setup.

高解像度フォノンアシスト準共鳴蛍光分光

High resolution optical spectroscopy methods are demanding in terms of either technology, equipment, complexity, time or a combination of these. Here we ...

Hand Controlled Manipulation of Single Molecules via a Scanning Probe Microscope with a 3D Virtual Reality Interface

Considering organic molecules as the functional building blocks of future nanoscale technology, the question of how to arrange and assemble such building blocks in a bottom-up approach is still open. The scanning probe microscope (SPM) could be a tool of choice; however, SPM-based manipulation was until recently limited to two dimensions (2D). Binding the SPM tip to a molecule at a well-defined position opens an opportunity of controlled manipulation in 3D space. Unfortunately, 3D manipulation is largely incompatible with the typical 2D-paradigm of viewing and generating SPM data on a computer. For intuitive and efficient manipulation we therefore couple a low-temperature non-contact atomic force/scanning tunneling microscope (LT NC-AFM/STM) to a motion capture system and fully immersive virtual reality goggles. This setup permits &#34;hand controlled manipulation&#34; (HCM), in which the SPM tip is moved according to the motion of the experimenter&#39;s hand, while the tip trajectories as well as the response of the SPM junction are visualized in 3D. HCM paves the way to the development of complex manipulation protocols, potentially leading to a better fundamental understanding of nanoscale interactions acting between molecules on surfaces. Here we describe the setup and the steps needed to achieve successful hand-controlled molecular manipulation within the virtual reality environment.

We demonstrate the precise manipulation of individual organic molecules on a metal surface with the tip of a scanning probe microscope driven in 3D by the experimenter's hand using a motion capture system and fully immersive virtual reality goggles.

3Dバーチャルリアリティのインターフェイスを持つ走査型プローブ顕微鏡を介した単一分子のハンド制御された操作

Considering organic molecules as the functional building blocks of future nanoscale technology, the question of how to arrange and assemble such building ...

Plasmonic Trapping and Release of Nanoparticles in a Monitoring Environment

Plasmonic tweezers use surface plasmon polaritons to confine polarizable nanoscale objects. Among the various designs of plasmonic tweezers, only a few can observe immobilized particles. Moreover, a limited number of studies have experimentally measured the exertable forces on the particles. The designs can be classified as the protruding nanodisk type or the suppressed nanohole type. For the latter, microscopic observation is extremely challenging. In this paper, a new plasmonic tweezer system is introduced to monitor particles, both in directions parallel and orthogonal to the symmetric axis of a plasmonic nanohole structure. This feature enables us to observe the movement of each particle near the rim of the nanohole. Furthermore, we can quantitatively estimate the maximal trapping forces using a new fluidic channel.

A microchip fabrication process that incorporates plasmonic tweezers is presented here. The microchip enables the imaging of a trapped particle to measure maximal trapping forces.

監視環境でのプラズモニックトラッピングとナノ粒子の放出

Plasmonic tweezers use surface plasmon polaritons to confine polarizable nanoscale objects. Among the various designs of plasmonic tweezers, only a few ...

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.

ハイパー レンズ一体型顕微鏡と超解像イメージングのデモ

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

Method for Recording Broadband High Resolution Emission Spectra of Laboratory Lightning Arcs

Lightning is one of the most common and destructive forces in nature and has long been studied using spectroscopic techniques, first with traditional camera film methods and then digital camera technology, from which several important characteristics have been derived. However, such work has always been limited due to the inherently random and non-repeatable nature of natural lightning events in the field. Recent developments in lightning test facilities now allow the reproducible generation of lightning arcs within controlled laboratory environments, providing a test bed for the development of new sensors and diagnostic techniques to understand lightning mechanisms better. One such technique is a spectroscopic system using digital camera technology capable of identifying the chemical elements with which the lightning arc interacts, with these data then being used to derive further characteristics. In this paper, the spectroscopic system is used to obtain the emission spectrum from a 100 kA peak, 100 &#181;s duration lightning arc generated across a pair of hemispherical tungsten electrodes separated by a small air gap. To maintain a spectral resolution of less than 1 nm, several individual spectra were recorded across discrete wavelength ranges, averaged, stitched, and corrected to produce a final composite spectrum in the 450 nm (blue light) to 890 nm (near infrared light) range. Characteristic peaks within the data were then compared to an established publicly available database to identify the chemical element interactions. This method is readily applicable to a variety of other light emitting events, such as fast electrical discharges, partial discharges, and sparking in electrical equipment, apparatus, and systems.

Emission spectroscopy techniques have traditionally been used to analyze inherently random lightning arcs occurring in nature. In this paper, a method developed to obtain the emission spectroscopy from reproducible lightning arcs generated within a laboratory environment is described.

実験室雷アークの広帯域高解像度発光スペクトルの記録方法

Lightning is one of the most common and destructive forces in nature and has long been studied using spectroscopic techniques, first with traditional ...