A Two-Dimensional Fluorescence Lifetime Imaging System Using a Gated Image Intensifier

Abstract

A simple fluorescence lifetime imaging system using a gated micro-channel plate (MCP) image intensifier coupled to a CCD camera has been developed. Nanosecond-level time-resolved fluorescence images of a sample under a pulsed light excitation can be detected directly. With a rapid lifetime determination method for multigate detection, fluorescence lifetime imaging can be promptly performed. In the present system, laser excitation of sample and shutter action of an image intensifier are fully synchronized by means of an optical fiber delay line. In order to compensate for fluctuations in the excitation source, a simple intensity monitor circuit was developed. Details of the instrumental system and verification measurements on two component samples are presented.