11:15 〜 11:30
▲ [15a-C31-6] Speed Enhancement in Frequency-Division-Multiplexed Confocal Microscopy by Multi-Line Focusing
キーワード：confocal microscopy, frequency division multiplexing, fluorescence microscopy
Laser-scanning confocal fluorescence microscopy is an essential method for biological and medical studies due to its high spatial resolution in three dimensions. Over the last decade, continuous efforts have been made toward the development of techniques for higher-speed confocal fluorescence microscopy in order to observe fast dynamics in biological tissues on the sub-millisecond time scale or to perform high-throughput imaging flow cytometry. Recently, a few techniques based on frequency-division multiplexing (FDM) have been reported to increase the frame rate of confocal fluorescence microscopy. However, the frame rates of these techniques are still limited by the scan rate of the mechanical scanning device employed in their systems, such as a resonant scanner or polygon scanner. Here we propose and experimentally demonstrate a method to overcome the limitation in frame rate in FDM-based confocal microscopy. In our method, in the same manner as previous FDM-based confocal microscopy techniques, intensity-modulated beam spots are aligned in a line on the target sample. Additionally, N duplicates of the aligned focal spots are simultaneously generated such that fluorescence signals from these spots are detected by a single photodetector. All of the spots are scanned altogether by an external scanning device such as a resonant scanner. Then, the sample is scanned N times, which substantially increase frame rate by a factor of N. In proof-of-concept experiment, we have obtained images of 10-μm fluorescence beads at a record high frame rate of 32,000 fps with N = 2. Experimental results in a setup of imaging flow cytometry will also be presented. We will also discuss signal-to-noise ratio (SNR) of an obtained image in different conditions in the presentation.