[17a-Z08-1~11] 3.8 Optical measurement, instrumentation, and sensor

△ [17a-Z08-7] Dead-time-less Measurement with Pseudo-noise Modulated Excitation Light for Fluorescence Lifetime Imaging

〇Hiromu Yamada¹, Keisuke Seto¹, Takayoshi Kobayashi², Eiji Tokunaga¹ (1.Tokyo Univ. Sci., 2.Univ. Electro-Comm.)

Keywords:fluorescence microscopy, fluorescence lifetime imaging, compressive sensing

Fluorescence lifetime imaging microscopy elucidates the surrounding environment (pH, temperature, ionic strength, etc.) of fluorescently labeled molecules. This fluorescence signal originates only from the initially excited molecule, and the molecules are not additionally excited during the decay measurement. Therefore, this methodology often requires a long accumulation time to obtain an adequate signal-to-noise ratio. In this study, we eliminate the "dead time" of no excitation during decaytime measurements. Here, the impulsive excitation of the conventional method is replaced by continuous wave excitation modulated by a pseudo-random series. The fluorescence decay curve is obtained from the correlation between the fluorescence signal and a time-shifted pseudo-random series.