Pulse detector with unworn-state detection

摘要

To detect whether the pulse detector is in an unworn state, the pulse detector is provided for detecting a pulse signal that originates in the pulse of a subject has a pulse wave sensor, a pulse wave sensor sensitivity adjustment section that adjusts the sensitivity of the pulse wave sensor, a body movement sensor, and an unworn-state detector that detects that the pulse detector has been removed from the subject and is in an unworn state, on the basis of the sensitivity of the pulse wave sensor sensitivity adjustment section and a body movement sensor signal outputted from the body movement sensor.

主权项

1. A pulse detector that detects a pulse signal originating from a pulse of a subject and an unworn state of the pulse detector, the unworn state being a state in which the pulse detector has been removed from the subject, the pulse detector comprising:
a pulse wave sensor outputting a pulse wave signal that includes the pulse signal; an amplifier amplifying the pulse signal; a pulse wave sensor sensitivity adjustment section that adjusts a sensitivity of the pulse wave sensor based on an input signal to the pulse wave sensor or an intensity of the pulse wave signal, the sensitivity being a gain of the amplifier; a body movement sensor that detects body movement of the subject and outputs a body movement sensor signal originating from the body movement; an unworn-state detector that detects, at predetermined time intervals, an unworn state; wherein to detect the unworn state at a current timing, which is subsequent to a previous timing with one of the predetermined time intervals between the previous timing and current timing, the unworn state detector; obtains the sensitivity, determines whether or not the unworn state has been detected at the previous timing,
wherein in response to determining that the unworn-state detector has detected the unworn state at the previous timing, setting a first level as a sensitivity threshold,wherein in response to determining that the unworn-state detector has not detected the unworn state at the previous timing, setting a second level, which is greater than the first level, as the sensitivity threshold; and wherein the unworn-state detector detects the unworn state at the current timing in response to determining that the sensitivity is greater than the sensitivity threshold, and determining that a level of the body movement sensor signal outputted from the body movement sensor is less than a predetermined movement threshold value.