PROBLEM TO BE SOLVED: To accurately perform blink detection in a non-contact manner without needing special circuit design.SOLUTION: In a blink detection method: a reflection wave from a subject is received by a Doppler sensor and a Doppler signal is created frequency analysis is performed for the Doppler signal, and a power spectrum of the Doppler signal is created the power spectrum is smoothed and separated into a plurality of discontinuous peak waveforms so that a feature amount waveform is created and a peak waveform indicating a blink is identified from the plurality of peak waveforms on the basis of a feature amount of the feature amount waveform.
