Improvement of the Detection Accuracy and Detection Limit of a Filter-less Fluorescence Detector

Filter-less fluorescence detectors (FFDs) do not require any optical filters for multicolor fluorescence detection. Therefore, a small and low-cost fluorescence detector is realizable, and applications to pathological examination and drug development are expected. In order to apply such devices to biochemical and medical diagnosis, it is important to detect weak fluorescence with high accuracy. However, in some situations, the fluorescence intensity may be less than 10-5 of the excitation light intensity. In this study, we experimentally demonstrate an FFD with improved detection accuracy and detection limit. By this approach, the detectable fluorescence intensity decreased to the dark-current level.