Patent ID: 7250029

Claim:
A human condition evaluation system comprising: a bio-signal measurement instrument effective to measure a bio-signal of a human and to gather bio-signal data based on said measurements, a bio-signal analyzer effective said bio-signal data; wherein said bio-signal analyzer includes; a bio-signal peak value detector effective to detect a maximum and minimum peak value for each cycle of an original waveform of the bio-signal data, a power value calculator effective to calculate a difference between the maximum peak value of said waveform and the minimum peak value of said waveform for each prescribed time range using respective peak values obtained by said bio-signal peak value detector to thereby set the difference as a power value, a gradient calculator effective to obtain a gradient of the power value with regard to time base in a certain time range by performing slide calculation a prescribed number of times at a prescribed overlap rate with regard to the prescribed time, and a comparative determinator effective to comparatively determine whether a sudden drop state of the gradient of the power value exists or not in time-series change in gradient of the power value obtained by performing the slide calculation to thereby determine the time range in which the sudden drop state appears to be a predictive signal for falling asleep from an active state into a sleep state.