Dr. Stephen Boppart and his research group have developed a novel way to time-tag and count photons for Fluorescence Lifetime Imaging Microscopy (FLIM) in real-time at a rate of 160 Mega-counts-per-second, double what the best commercial system can do. The invention utilizes an accurate synchronization, fast detection with an analog PMT, high-bandwidth transimpedance amplifier, fast digitizer, and a GPU-accelerated photon-counting algorithm.