Simple setup for nanosecond time-resolved spectroscopic measurements by a digital storage oscilloscope

An application of a digital storage oscilloscope for nanosecond time-resolved spectroscopic measurements is demonstrated in the range from the single-photon region to the multi-photon region. In comparison to the time-correlated single photon counting (TCSPC) method, the measurement setup can be greatly simplified by averaging the signals measured by the oscilloscope. Moreover, the multi-photon events of the fluorescence emissions can be tracked by this simple setup although there still exist some disadvantages in the dynamic range of the signal due to radio frequency noise, and the temporal response of the photo-multiplier tube. This method can simplify time-resolved optical measurements in the nanosecond range, such as fluorescence decay and time-of-flight measurements of diffusing light. Thus, this simple method will be applicable in many clinical and industrial uses.