Display device and blood pressure measurement method using the same

A blood pressure measurement method using a display device, comprising:

• generating a first pulse wave frequency signal by a main processor included in the display device, the first pulse wave frequency signal having a magnitude of a pulse wave signal according to a frequency having a fundamental wave component and a harmonics component based on a pressure measurement value that is sensed by a pressure sensor disposed on a display panel included in the display device and sensing a pressure applied from outside of the display device and a pulse wave signal that is sensed by a photo-sensor disposed on the display panel and sensing light;
• calculating a coefficient of a transfer function by the main processor, the coefficient of the transfer function is based on center frequencies and maximum gains at center frequencies of first harmonics to third harmonics of the first pulse wave frequency signal;
• generating a second pulse wave frequency signal by the main processor, the second pulse wave frequency signal is generated by changing the maximum gains of the first harmonics to the third harmonics of the first pulse wave frequency signal based on the transfer function;
• generating a second pulse wave signal by the main processor, the second pulse wave signal having a magnitude of a pulse wave signal according to a pressure based on the second pulse wave frequency signal;
• and
• calculating blood pressure information by the main processor based on the second pulse wave signal and displaying the blood pressure information on a display panel of the display device,
• wherein one cycle of the second pulse wave signal includes a plurality of waveforms having different amplitudes from each other, and a peak value of a first waveform of the plurality of waveforms is greater than a peak value of a second waveform of the plurality of waveforms,
• wherein the calculating of the coefficient of the transfer function based on the center frequencies and the maximum gains at the center frequencies of the first harmonics to the third harmonics of the first pulse wave frequency signal includes:
• calculating a first center frequency and a maximum gain at the first center frequency of the first harmonics of the first pulse wave frequency signal, a second center frequency and a maximum gain at the second center frequency of the second harmonics of the first pulse wave frequency signal, and a third center frequency and a maximum gain at the third center frequency of the third harmonics of the first pulse wave frequency signal;
• and
• calculating cutoff frequencies based on the center frequencies,
• wherein the calculating of the cutoff frequencies based on the center frequencies includes calculating a first cutoff frequency as corresponding to a half of the first center frequency,
• wherein the transfer function includes a first transfer function blocking a noise component of the first harmonics in a section from the first cutoff frequency to the first center frequency,
• wherein the first transfer function is calculated by
• H
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• kw
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• in which H1(x) is the first transfer function, wo1 is the first center frequency, k is the maximum gain of the first center frequency, wc1 is the first cutoff frequency, and N is a natural number of 2 or more.

An electronic device, comprising:

• a display device comprising:
• a display panel including pixels displaying an image;
• a pressure sensor disposed on the display panel and sensing a pressure applied from outside of the display device;
• a photo-sensor disposed on the display panel and sensing light;
• and
• a main processor receiving a pressure measurement value that is sensed by the pressure sensor and a pulse wave signal that is sensed by the photo-sensor,
• wherein the main processor generates a first pulse wave frequency signal having a fundamental wave component and a harmonics component according to the pressure measurement value and the pulse wave signal, generates a second pulse wave frequency signal by blocking noise of the harmonics component of the first pulse wave frequency signal, generates a first pulse wave signal based on the second pulse wave frequency signal, and calculates blood pressure information based on the first pulse wave signal,
• wherein each of the first pulse wave frequency signal and the second pulse wave frequency signal is a magnitude of the pulse wave signal according to a frequency, and the first pulse wave signal is a magnitude of the pulse wave signal according to the pressure measurement value,
• wherein the main processor calculates a coefficient of a transfer function based on center frequencies and maximum gains at center frequencies of first harmonics to third harmonics of the first pulse wave frequency signal,
• wherein the calculating of the coefficient of the transfer function based on the center frequencies and the maximum gains at the center frequencies of the first harmonics to the third harmonics of the first pulse wave frequency signal includes:
• detecting a first center frequency and a maximum gain at the first center frequency of the first harmonics of the first pulse wave frequency signal, a second center frequency and a maximum gain at the second center frequency of the second harmonics of the first pulse wave frequency signal, and a third center frequency and a maximum gain at the third center frequency of the third harmonics of the first pulse wave frequency signal;
• and
• calculating cutoff frequencies based on the center frequencies,
• wherein the calculating of the cutoff frequencies based on the center frequencies includes calculating a first cutoff frequency as corresponding to a half of the first center frequency,
• wherein the transfer function includes a first transfer function blocking a noise component of the first harmonics in a section from the first cutoff frequency to the first center frequency,
• wherein the first transfer function is calculated by
• H
• ⁢
• 1
• ⁢
• (
• x
• )
• =
• k
• w
• 01
• N
• -
• w
• c
• ⁢
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• N
• ⁢
• x
• N
• +
• -
• kw
• c
• ⁢
• 1
• N
• w
• 01
• N
• -
• w
• c
• ⁢
• 1
• N
• in which H1(x) is the first transfer function, war is the first center frequency, k is the maximum gain of the first center frequency, wc1 is the first cutoff frequency, and N is a natural number of 2 or more.