Electron microscopy (EM) is a powerful imaging technique renowned for its outstanding spatial resolution. It surpasses the theoretical maximum. Resolving power of conventional microscopy by several orders of magnitude, enabling researchers to probe nanoscale structures and to resolve the chemical composition of samples with unprecedented precision. However, standard EM systems are typically unsuited to monitoring the change of macromolecular structures over time. For that, researchers must employ time-resolved electron microscopy.
SEMとTEMの簡単な紹介
時間分解電子顕微鏡の基本を掘り下げる前に、EMの基本的な動作原理を概説することは価値があります。
従来の顕微鏡法では、可視光を使用して、理論上の最大値である1000倍まで物体/表面を拡大します。 この解像限界と呼ばれるものは、可視光の波長によってもたらされるものです。 電子は、人間の目で検出できる光よりもはるかに短い波長を持っています。 実際、電子ビームを使用して、前例のない200,000倍までの物体を、並外れた化学的特異性で拡大することができます。
There are two main types of EM: scanning electron microscopy (SEM), and transmission electron microscopy (TEM). These differ in the way that samples are illuminated. However, each one uses the same basic apparatus to generate a focused electron beam which is directed onto the object of interest. They differ in that an SEM uses a series of deflector coils to alter the beam path. Raster scan the sample, while a TEM uses a fluorescent screen to generate a projection image. Each of these systems tends to use a continuous wave (CW) electron beam, which cannot provide relevant temporal data.
時間分解能のファクタリング
Although many critical dynamics and structures can be investigated using traditional SEM or TEM, it is often important to analyse systems at more stringent timescales. Time-resolved electron microscopy is employed where researchers need to correlate their spatial data with ultrafast temporal resolution. This solution has been developed as a direct result of relatively recent advances in laser technology. Particularly, in the field of ultrafast pulsed wave (PW) laser systems. Femtosecond laser technology – with ultrashort pulses and high repetition rates – is the leading solution for this space.
時間分解電子顕微鏡システムの動作の基本原理は、これらの電子ビーム・パルスの長さによって決定される特定の間隔で迅速なスナップ・ショットをキャプチャする短い電子パルスでサンプルを照射することを含みます。 ほとんどの時間分解電子顕微鏡電子ビームは、フェムト秒領域に近づくパルスを特徴としており、高い空間分解能と時間分解能の両方で、サンプルの組成、ダイナミクス、および構造に関する詳細な洞察を提供します。
時間分解電子顕微鏡ソリューション
Through our Laser Quantum product brand, we are the world-leading manufacturer of ultrafast laser sources for demanding areas of application. We offer time-resolved electron microscopy solutions based on our own proprietary ultrafast laser systems. If you would like to learn more about using femtosecond lasers for time-resolved EM, contact us below.