题目：Recent Advances in TCSPC Fluorescence Lifetime Imaging Microscopy(FLIM)
时间：9月16日（周三）下午3点
地点：光电工程学院三楼多功能厅
报告人：Dr. Wolfgang Becker（Becker & Hickl GmbH）
主持人：屈军乐 教授
报告人简介：Wolfgang Becker博士是时间分辨光学显微成像方面的专家。于1979个在德国柏林取得博士学位，1993年开始在柏林创建了Becker & Hickl GmbH公司。主要研究领域为时间相关单光子计数技术的应用及发展。在本领域担任多个杂志的审稿人。
摘要：TCSPC FLIM is based on a multi-dimensional time-correlated single-photon counting process. The sample is scanned with the focused beam of a high-repetition rate pulsed laser, and single photons of the fluorescence light returning from the sample are detected. Each photon is characterised by its time in the laser pulse period and the coordinates of the laser spot in the scanning area in the moment its detection. The recording process builds up a photon distribution over these parameters. The result is an array of pixels, each containing a full fluorescence decay curve in a large number of time channels.
Recent advances in TCSPC FLIM were driven by more efficient microscope and scanner optics, more efficient detectors, and 64-bit data acquisition software. As a result, FLIM can be recorded at a spatial resolution in the megapixel range. This allows a large number of cells to be imaged simultaneously under identical experimental conditions and thus obtain exactly comparable FLIM parameters from them. High pixel numbers are also important for super-resolution FLIM by the stimulated-emission-depletion (STED) technique. Modern STED FLIM implementations are able to image an area larger than an entire cell at a resolution of better than 30 nm.
TCSPC FLIM can further be extended to record photon distributions that includes additional parameters of the photons. Such parameters can be the wavelength of the photons, additional spatial parameters, the time after a stimulation of the sample, or the time within the period of an additional modulation of the laser. These techniques can be used to record multi-wavelength FLIM images, FLIM Z stacks, images of physiological effects occurring in the sample, and to simultaneously record fluorescence and phosphorescence lifetime images. Potential applications are the measurement of fast changes in the Ca2+ concentration in neurons on electrical stimulation, or the combination of metabolic imaging experiments with oxygen concentration measurement.
