Abstract: A contact pressure sensor including a semiconductor chip having opposite surfaces, at least one pressure sensing element provided in one of the opposite surfaces of the chip, a spacer member supporting the other surface of the chip, a substrate having a surface to which the spacer member is fixed, the one surface of the chip being pressed against an object which produces a pressure, so that the at least one sensing element detects the pressure produced by the object, a first connection terminal provided in the one surface of the chip, a second connection terminal provided in the surface of the substrate, and a flexible flat cable connecting between the first and second connection terminals, the flexible flat cable being bent into two portions one of which extends along a side surface of the spacer member and the other of which extends along the surface of the substrate.

Abstract: A pulse wave detecting apparatus, including a pulse wave sensor having a press surface on which a plurality of pressure sensing elements are provided in an array, a main device receiving an electric signal from each of the pressure sensing elements, a determining device determining a correlation between a distribution of magnitudes of the electric signals as taken along the array of pressure sensing elements, and each of a plurality of predetermined reference distributions which is indicative of a corresponding one of a plurality of different relative positions of the array of pressure sensing elements with respect to the blood vessel, a selecting device selecting one of the reference distributions which provides the greatest correlation of all the correlations determined by the determined device, and a transmitting device transmitting to the main device the electric signals generated from the pressure sensing elements in a portion of the array of pressure sensing elements which portion corresponds to the rel

Abstract: A calibration system for a continuous blood pressure monitoring system using a tonometric sensor for continuously detecting a pulse wave comprises a digital cuff adapted to be placed around a digit of the patient for applying a calibration pressure to the digit; a pressure source coupled to the digital cuff for supplying the calibration pressure; a calibration sensor for measuring an actual blood pressure in the digit; and a microprocessor for determining a calibration factor for the tonometric sensor based on the actual blood pressure measured by the calibration system. The digital cuff is located on the patient such that the cuff is downstream of the artery over which the tonometer sensor is located. According to one aspect of the invention, a digital cuff pressure sensor is connected to the pressure source for determining the magnitude of the calibration pressure and a pulsatile component indicative of blood pressure in the digit.

Abstract: An improved pressure sensor element and pressure sensor array is formed by a cathode layer, a cathode tip attached to the cathode layer, and an anode layer opposing the cathode layer. The magnitude of the electron current flowing between the cathode tip and the anode layer is dependant on the field strength at the cathode tip, which is dependant on the separation between the cathode tip and the anode layer. As a deflectable anode layer is deflected towards the cathode tip, the field strength increases, causing a corresponding change in the magnitude of the flow of electrons. The cathode tip is separated from the anode layer such that electron current is produced at relatively low voltages by tunneling or field emission. The exact method of current production is selected by controlling the initial separation between the anode layer and the cathode tip.

Abstract: A monitoring system for providing an accurate indication of a patient's respiration rate. The system is effective in eliminating or significantly reducing the effects of heart sounds and ambient noise. The system comprises means for obtaining a first signal waveform containing components corresponding to the patient's breath sounds, as well as components corresponding to heart sounds and ambient noise. The signal is passed through a digital bandpass filter having a passband selected to remove heart sounds and ambient noise to produce a second waveform. From the second waveform the total energy is computed of a portion of the signal within a moving window of predetermined length. The resulting energy envelope signal is smoothed and then high-pass filtered by removing the average DC value of the signal over a predetermined preceding time interval. Respiration is detected by identifying significant, positive-going zero crossings of the resulting signal through a band about zero.

Abstract: An apparatus for detecting a pulse wave produced from a subject in synchronous relationship with heartbeats of the subject, including a probe device for sensing a heartbeat synchronous pulse wave transmitted thereto and generating a signal representative of the sensed pulse wave, a sampling device for periodically determining a magnitude of the signal, a determining device for determining a lower peak and a following upper peak of the heartbeat synchronous pulse wave based on variation of the magnitudes determined by the sampling means, a calculating device for calculating a value by subtracting, from each of the magnitudes determined by the sampling means, a magnitude of the signal determined by the sampling means prior by a predetermined number of periods to the each of the magnitudes, and a judging means for judging whether or not the following upper peak is a proper upper peak of a pulse of the heartbeat synchronous pulse wave, based on the values calculated by the calculating means with respect to a port

Abstract: Pulse wave is detected by a pulse wave sensor pressed against an arterial vessel of living body. Stability of detection of the pulse wave may be insufficient due to not only inappropriate pressing of the pulse wave sensor but also the living body itself. The insufficient stability of detection of pulse wave resulting from the living body itself cannot be solved by altering the manner of pressing of the pulse wave sensor, but it can be solved by, for example, changing the angle of a hand about the wrist and thereby detecting a pulse wave produced from the radial artery running in the wrist. The present invention has made it possible to automatically identify the insufficient stability of detection of pulse wave due to the living body itself.

Abstract: A pulse wave detecting apparatus for detecting a pulse wave produced from an arterial vessel in a body portion of a subject, including a semiconductor substrate having a press surface at which the semiconductor substrate is adapted to be pressed against the body portion, the semiconductor substrate having a recess in a surface thereof opposite to the press surface and thereby including a diaphragm portion having a thin wall, and a pressure sensing device provided on the diaphragm portion, for converting a pressure transmitted from the arterial vessel to the diaphragm portion, into an electric signal.

Abstract: A pulse oxymeter for measuring a blood oxygen saturation of a subject, including a first device for emitting toward a body portion of the subject a first light having a first wavelength and a second light having a second wavelength different from the first wavelength, a second device for detecting an intensity of each of the first and second lights transmitted through, or reflected by, the body portion of the subject and generating a photoelectric pulse wave signal representative of the detected intensity of each of the first and second lights, a third device for determining a blood oxygen saturation of the subject based on the pulse wave signals corresponding to the first and second lights, a probe which supports the first and second devices and is adapted to contact the body portion of the subject, and a warming device for warming the body portion of the subject.

Abstract: A pulse wave detecting apparatus including a pulse wave sensor; a pressing device for pressing the sensor against an arterial vessel of a subject, while varying the pressing force; a first device for determining an amplitude of each of pulses of pulse wave which are detected by the sensor while the pressing force is varied; a second device for determining, based on the determined pulse amplitudes, a first range of the pressing force within which the pulse amplitudes are generally constant, the first range including a point at which a rate of change of the pulse amplitudes with respect to the pressing force is zero; a third device for determining a minimum value of each of the pulses detected by the sensor; a fourth device for determining, based on the determined pulse minimum magnitude, a second range of the pressing force within which the pulse minimum magnitudes are generally constant, the second range including a point at which a rate of change of the pulse minimum magnitudes with respect to the pressing f

Abstract: An apparatus for detecting a heartbeat synchronous wave produced from a subject in synchronization with heartbeat of the subject, including a probe which is adapted to be set on a body portion of the subject, a sensor for detecting the heartbeat synchronous wave produced from the subject, the sensor being supported by the probe, a judging device for judging whether or not an electric knife is being used on the subject, and a device for, if the judging device judges that the electric knife is being used, ceasing from detecting the heartbeat synchronous wave, or discarding the heartbeat synchronous wave detected when the electric knife is being used. The judging device may be adapted to detect a high frequency electric current flowing from an electric knife to the probe via the body portion of the subject, and judge whether or not the electric knife is being used on the subject, based on the detected high frequency electric current.

Abstract: A pulse wave detecting apparatus including a sensing device sensing a pulse wave produced from an arterial vessel of a subject, a storing device concurrently storing the pulse wave signals generated by pressure sensing elements of the sensing device, a selecting device selecting, as an optimum pressure sensing element, one of the pressure sensing elements such that an amplitude of the pulse wave signal from the selected one element is the greatest of the amplitudes of the pulse wave signals stored in the storing means, a judging device judging whether or not the pulse wave signal from the selected one element is abnormal, and a changing device which, if an affirmative judgement is provided by the judging device, changes the optimum pressure sensing element from the selected one element to another of the pressure sensing elements such that an amplitude of the pulse wave signal from the selected another element is the greatest of the amplitudes of the pulse wave signals which are stored in the storing device co

Abstract: A semiconductor sensor for detecting a pressure pulse wave produced from an arterial vessel of a subject, including a semiconductor substrate including a thin portion obtained by locally forming a recess in one of opposite surfaces of the semiconductor substrate, at least one semiconductor pressure sensing element supported by the thin portion of the semiconductor substrate, for converting a pressure pulse wave transmitted from the arterial vessel to the thin portion, into an electric signal, and at least one semiconductor active element supported by the semiconductor substrate, for converting the electric signal into a different electric signal, the at least one active element including a portion of the semiconductor substrate.

Abstract: It is desirable to minimize discomfort of a living body due to pressing by a blood pressure monitoring system of a type which monitors the blood pressure of the living body for a long period of time. The present invention is constituted by including pulse wave detecting device for detecting pulse waves of an arterial vessel of a living body, blood pressure measuring device for measuring an actual blood pressure of the living body, and control device for determining a relationship between the pulse waves detected by the pulse wave detecting device and the actual blood pressure measured by the blood pressure measuring device, determining blood pressures according to the thus-determined relationship and based on the pulse waves, and commanding a display to continuously display the thus-determined blood pressures thereon.

Abstract: An oximeter system for measuring blood oxygen saturation using a noninvasive optical technique is disclosed. A patient's arterial blood is illuminated with light at two different wavelengths and the intensity of the light which is transmitted through or reflected by said arterial blood is correlated with the blood oxygen saturation of the tissue. The system provides a manner in which filtering artifacts are avoided in the oximeter signal using a high resolution analog-to-digital converter of 14 bits or more, such that, it is unnecessary to separate the DC and pulsatile components of the oximeter signal prior to processing within the microprocessor.

Abstract: A method and apparatus for determining and compensating for the crosstalk behavior and element spacing of an arterial tonometer sensor in order to obtain a more accurate blood pressure measurement. The crosstalk behavior and the effects of element spacing in a tonometer sensor having a plurality of sensing elements located on a single diaphragm is derived using advanced modeling techniques. An error correction factor look-up table is computed and applied to an uncorrected blood pressure measurement, resulting in increased accuracy.

Abstract: An apparatus for automatically measuring a blood pressure of a subject, including a pressing device for pressing a body portion of the subject, such as an upper arm; a first blood pressure measuring device for detecting pulse sounds which are produced from the body portion as the pressing force of the pressing device is varied, and determining a first blood pressure (BP) value of the subject based on at least one of an appearance and a disappearance of the pulse sounds; a second blood pressure measuring device for detecting an oscillatory pressure wave which is produced from the body portion in synchronization with heartbeat of the subject as the pressing force of the pressing device is varied, and determining a second BP value of the subject based on variation in magnitude of the oscillatory pressure wave; and a judging device for judging at least one of the first and second blood pressures to be abnormal if a degree of inequality between the first and second blood pressures exceeds a reference value.

Abstract: A method and an apparatus for measuring blood pressure of a subject by using a pulse wave sensor for detecting pulse wave produced from an arterial vessel of the subject, and pressing device for pressing the pulse wave sensor against the arterial vessel via a body surface of the subject, the method comprising the steps of pressing the pulse wave sensor against the arterial vessel with a continuously variable pressing force produced by the pressing device, detecting variation in magnitude of the pulse wave with the pulse wave sensor while the pressing force of the pressing device is continuously varied, and determining blood pressure of the subject based on the detected magnitude variation of the pulse wave.

Abstract: An automatic blood pressure measuring apparatus, including an inflatable cuff having an elongate configuration, the inflatable cuff being wound around a body portion of a subject, for pressing an arterial vessel of the subject via a body surface over the arterial vessel, a detecting device for detecting at least one Korotkoff sound produced from the arterial vessel as the pressing force of the inflatable cuff applied to the arterial vessel is varied, and a determining device for determining at least one blood pressure value of the subject based on the detected at least one Korotkoff sound, the detecting device being located in a middle area, as viewed in a direction of width of the inflatable cuff, of an inner surface of the inflatable cuff which surface contacts the body portion of the subject.

Abstract: An apparatus for automatically measuring a blood pressure of a subject, including a device for defining an inflatable pressure chamber, the device being set on a body portion of the subject, a flexible piping, a device for supplying a pressurized fluid to the inflatable pressure chamber via the flexible piping so as to increase fluid pressure in the pressure chamber and thereby press the body portion of the subject, and a relief device for discharging the pressurized fluid in the inflatable pressure chamber, into atmosphere, if the fluid pressure in the pressure chamber exceeds a predetermined value, the relief means being supported by the means for defining the pressure chamber.