Method for estimating a cardiac frequency and associated device

A Method for estimating a cardiac frequency of a living being including the following steps:

• a) illuminating a bodily zone of the living being with an incident light beam in a first spectral band;
• b) detecting light radiation transmitted or backscattered, in the first spectral band, by the bodily zone under the effect of the illumination;
• c) determining a first detection function, representing a variation as a function of time of an intensity of the light radiation thus detected;
• d) identifying characteristic instants from the first detection function, and calculating an occurrence frequency of the characteristic instants;
• e) estimating a cardiac frequency from the occurrence frequency calculated in step d);
• wherein:
• steps a) to b) are also implemented in a second spectral band, such that step c) includes determining a second detection function representing a variation as a function of time of an intensity of the light radiation detected in the second spectral band;
• step d) includes identifying characteristic instants from the second detection function and selecting characteristic instants, identified from each detection function, and appearing in temporal coincidence, the occurrence frequency being calculated from the characteristic instants thus selected.