Abstract: A support apparatus for supporting at least a portion of a patient's limb during a procedure. The apparatus includes a support having a surface for receiving at least a portion of the patient's limb thereon to support the limb during the procedure, and a sensor mounted on the support such that the sensor is at least partially attached to the support without an adhesive. The sensor is adapted to communicate with the patient's limb for measuring a physiological parameter of the patient on the limb when the limb is supported by the support.

Abstract: A pulse wave detecting apparatus, including a pressure pulse wave sensor 30 which detects a pulse wave produced from a living subject and outputs a pulse wave signal SM representing the detected pulse wave, a signal converting device 78 which modulates, by using the pulse wave signal SM as a modulating signal, an audible frequency of a to-be-modulated signal, and thereby provides a modulated signal having audible frequencies, and a speaker 62 which outputs a sound representing the modulated signal provided by the signal converting device 78.

Abstract: Processing of plethysmographic signals via the cepstral domain is provided. In one embodiment, a cepstral domain plethysmographic signal processing method (200) includes the steps of obtaining (210) time domain plethysmographic signals, smoothing (220) the time domain plethysmographic signals, performing (230) a first-stage Fourier transformation of the time domain plethysmographic signals to frequency domain plethysmographic signals, computing (240) power spectrums from the frequency domain plethysmographic signals, scaling (250) the power spectrums with a logarithmic function, performing (260) a second-stage Fourier transformation on log-scaled spectrums to transform the power spectrums into cepstrums, and examining (270) the cepstrums to obtain information therefrom relating to a physiological condition of the patient such as the patient's pulse rate or SPO2 level.

Abstract: A subject evaluation value measuring apparatus 10, functioning as a cuff volumetric pulse wave obtaining apparatus, includes a pulse wave determining device (i.e., a cuff volumetric pulse wave determining device) 52 that determines, using an inverse transfer function 1H(f), stored in a ROM (i.e., an inverse transfer function memory) 42, that corresponds to a pre-determined transfer function H(f) between input, i.e., pressure pulsation produced in a cuff 20, and output, i.e., pressure pulsation detected by a pressure sensor 24, a no-delay cuff volumetric pulse wave PK(t) having substantially no delay of transmission, based on an actual cuff pulse wave signal SM outputted by the pressure sensor 24. The thus determined cuff volumetric pulse wave PK(t) is free of waveform distortion and accordingly enjoys high accuracy.

Abstract: The invention relates to a sensor (42) placed on the skin, which can advantageously be integrated in a garment and has a contact layer in contact with the skin containing conductive fibres for receiving signals and a moisture retentive moisture layer (41) on top of the contact layer.

Abstract: A method and apparatus for controlling alarms in a medical diagnostic apparatus where an alarm is generated when a measured value for a physiological parameter is outside a specified range. The method continuously calculates a baseline value, and establishes dynamic thresholds that are related to and continuously track the baseline value. The method determines the amount of time the measured value is past the dynamic threshold, and the amount by which the threshold is passed. Alarms are triggered based upon a combination of the amount of time and the amount by which the threshold is passed. Preferably, the combination is an integral or some function of an integral.

Abstract: A method and apparatus for the application of Blind Source Separation (BSS), specifically independent Component Analysis (ICA) to mixture signals obtained by a pulse oximeter sensor. In pulse oximetry, the signals measured at different wavelengths represent the mixture signals, while the plethysmographic signal, motion artifact, respiratory artifact and instrumental noise represent the source components. The BSS is carried out by a two-step method including an ICA. In the first step, the method uses Principal Component Analysis (PCA) as a preprocessing step, and the Principal Components are then used to derive sat and the Independent Components, where the Independent Components are determined in a second step. In one embodiment, the independent components are obtained by high-order decorrelation of the principal components, achieved by maximizing the sum of the squares of the higher-order cumulants of the plurality of mixture signals.

Abstract: An ultrasound information processing system is disclosed in which ultrasound image data is packetized into ultrasound information packets and routed to one or more of a plurality of processors for performing image processing operations on the ultrasound image data, the ultrasound information packets being routed according to entries in a host-programmable routing table. A common distribution bus is coupled between packetizing circuitry and dedicated input buffers corresponding to each processor for distributing the ultrasound information packets, and a common output bus to is used to transfer processed image data from the processors to an output device. The disclosed ultrasound information processing system architecture allows for a high throughput rate for accommodating real-time image processing operations, while also allowing for ready programmability and upgradability.

Abstract: A pulse wave monitor includes a sensor unit having a pulse wave sensor and a base. The base of the pulse wave monitor is mounted on a wrist of a subject. A finger or a detector is inserted through the pulse detecting hole provided on the base so as to detect an artery of the subject, and the base is fixed to the wrist of the subject by a belt so that the artery comes to a center of the base. The sensor unit is engaged with the base by a clip. A preliminary position relationship between the sensor unit and the artery is detected. When the position of the sensor unit must be adjusted, the sensor unit is slid to cover a predetermined number of graduations. This adjustment allows the sensor unit to be at an optimal position so that a pulse wave of the subject is measured. As a result, it is possible to provide a pulse wave monitor capable of quickly performing positioning with high accuracy.

Abstract: A pulse and active pulse spectraphotometry system comprises a light source adapted to illuminate a tissue site with optical radiation having a plurality of wavelengths selected from at least one of a primary band and a secondary band. The tissue site has a modulated blood volume resulting from the pulsatile nature of arterial blood or from an induced pulse. A detector is configured to receive the optical radiation attenuated by the tissue site and to generate a detector output responsive to absorption of the optical radiation within the tissue site. A normalizer operating on the detector output generates a plurality of normalized plethysmographs corresponding to the plurality of wavelengths. Further, a processor is configured to calculate a ratio of fractional volumes of analytes in the blood volume based upon the normalized plethysmographs.

Abstract: Processing of plethysmographic signals via the cepstral domain is provided. In one embodiment, a cepstral domain plethysmographic signal processing method (200) includes the steps of obtaining (210) time domain plethysmographic signals, smoothing (220) the time domain plethysmographic signals, performing (230) a first-stage Fourier transformation of the time domain plethysmographic signals to frequency domain plethysmographic signals, computing (240) power spectrums from the frequency domain plethysmographic signals, scaling (250) the power spectrums with a logarithmic function, performing (260) a second-stage Fourier transformation on log-scaled spectrums to transform the power spectrums into cepstrums, and examining (270) the cepstrums to obtain information therefrom relating to a physiological condition of the patient such as the patient's pulse rate or SPO2 level.

Abstract: The invention presents a system for confirming a performer of a fitness exercise. The system includes a heart rate monitor (104) for measuring heart rate parameters (404A to 404N) associated with the fitness exercise from the heart rate of the performer. The system also includes a mathematical model (406) including dependence information between heart rate parameters (404A to 404N) and classes classifying the performer in classes (402A to 402N) such as age or weight. Heart rate parameter data measured from the performer and information in the mathematical model are utilized in identifying the performer of the fitness exercise.

Abstract: There is provided a pulse wave detecting apparatus capable of clearly discriminating pulsations from noise having a small storage amount and also a small computation amount. In the pulse wave detecting apparatus, while an oscillator unit transmits ultrasonic waves toward an object under examination and a receiver receives reflection waves reflected from the object under examination, a detecting unit converts the reflection waves from the pulse waves. A pulsation detecting unit predicts timing of a next pulsation from an interval of previously acquired pulsation and pulse, detects a peak of a pulse wave which is larger than a predetermined value within the zone Z located before/after the predicted timing of the pulsation. Then, this pulsation detecting unit specifies such a peak having a timing which is located at the nearest timing with respect to the predicted timing among each of these peaks.

Abstract: A vital signal detecting apparatus is composed of sensors for detecting pulse waves, an A/D converter for converting analog signals, corresponding to the pulse waves and derived from the sensors, into digital signals, a separation matrix calculation means, and a signal separation calculation circuit. The separation matrix calculation circuit calculates a separation matrix for separating an outer disturbance caused by body movement from the pulse waves. The signal separation calculation means divides the digital signals converted by the A/D converter into a vital signal containing no outer disturbance and a body movement signal indicating the outer disturbance by using the separation matrix.

Abstract: A pleth signal is analyzed to identify a heart rate variability parameter associated with respiration rate. In one embodiment, an associated process involves obtaining a photoplethysmograpic signal, processing the pleth signal to obtain heart rate samples, monitoring the heart rate sample to identify a heart rate variability associated with respiration, and determining a respiration rate based on the heart rate variability. The photoplethysmographic signal may be based on one or more channel signals of a conventional pulse oximeter. The invention thus allows for noninvasive monitoring of respiration rate and expands the functionality of pulse oximeters.

Abstract: The present invention disclosed relates to heart beat analysis device and method capable of measuring the heart beats of an individual in physical exercise, notifying the individual of a suitable exercise amount with messages or warning sounds, and allowing the individual to listen to the radio or music.

Abstract: A vital signal detecting apparatus comprises an attachable device to be attached to a finger, a sensor having a light-emitting device and a light-receiving device, and a transmitting circuit for transmitting a signal waveform as a pulse wave from the sensor to a pulse wave monitoring unit. The pulse wave detecting unit also has an attachment detecting circuit for detecting whether or not the attachable device is in an attached state by comparing a signal waveform obtained when the light-emitting device is on with a signal waveform obtained when the light-emitting device is off and an operation control circuit for controlling the operation of the sensor, the transmitting circuit and the attachment detecting circuit. Preferably, the light-transmitting plate is disposed above the light-emitting device and the light-receiving device to pass light therethrough, and the light transmitting plate may be an IR-cut filter capable of blocking light of wavelengths greater than 700 nm.

Abstract: The present invention refers to a system and a method for the automatic evaluation of the indexes of volemic status (Systolic Pressure Variation or SPV) in patients submitted to mechanic ventilation, starting form the analysis of the variations of the values of blood pressure.

Abstract: A homodyne interference system splits first and second light beams from a common light source and causes the first and second light beams to impinge upon an irradiating point of an organism at different directions. An optical heterodyne system splits a third beam from the common light source and imparts a frequency shift to the third beam. The outputs of the homodyne and heterodyne systems combine to permit extraction of a beat component of the homodyne system at a high SNR level. The output of the homodyne and heterodyne system are output as an image, which may be timed to a phase timing mechanism to provide an improved output.

Abstract: The invention comprises devices and methods for the noninvasive monitoring of a physiologic characteristic of a patient's blood, such as blood pressure. One embodiment is a tissue probe combined with a position sensor for determining the relative height of the probe compared to a level corresponding to the patient's heart. Alternatively, the tissue probe can be combined with a movement generator for inducing a height change of the probe with respect to patient's heart. By measuring absorbance characteristics of the blood at varying positions relatively to the level of the patient's heart, characteristics such as arterial and central venous blood pressure and cardiac output can be determined. In yet another embodiment, two probes are used to compute pulse delays between coupled tissues or opposing tissues. Measuring delays in pulse arrival times in coupled organs or members on opposite sides of the body allows the determination of various physiological characteristics.

Abstract: A method of monitoring a subject (7) in a vehicle seat (6), the method including: a) acquiring a target signal from the subject with a piezoelectric transducer (1) provided in or on the vehicle seat; b) processing the target signal to extract a cardiac signal (24) and/or a respiratory signal (25); and c) outputting the cardiac and/or respiratory signal. A method of monitoring a subject including: a) acquiring a target signal from the subject; b) bandpass filtering (27) the target signal in accordance with a set of cardiac filter coefficients to extract a cardiac signal (24); c) bandpass filtering (30) the target signal in accordance with a set of respiratory filter coefficients to extract a respiratory signal (25); d) adapting (29, 33) the set of cardiac filter coefficients so as to reduce artefacts in the cardiac signal; e) adapting (50, 32) the set of respiratory filter coefficients so as to reduce artefacts in the respiratory signal; and f) outputting the cardiac and respiratory signal signals.

Abstract: A pulse wave sensor for detecting a pulse wave by detecting light output from a light emitting diode and reflected from the artery of a wrist of a subject, the sensor comprising four photodetectors disposed around the light emitting diode symmetrically on a circle concentric to the light emitting diode, and a pulse rate detector comprising the pulse wave sensor and means of computing the pulse rate of a subject based on the output of the pulse wave sensor.

Abstract: An intelligent, rule-based processor provides recognition of individual pulses in a pulse oximeter-derived photo-plethysmograph waveform. Pulse recognition occurs in two stages. The first stage identifies candidate pulses in the plethysmograph waveform. The candidate pulse stage identifies points in the waveform representing peaks and valleys corresponding to an idealized triangular wave model of the waveform pulses. At this stage, waveform features that do not correspond to this model are removed, including the characteristic dicrotic notch. The second stage applies a plethysmograph model to the candidate pulses and decides which pulses satisfies this model. This is done by first calculating certain pulse features and then applying different checks to identify physiologically acceptable features.

Abstract: In a pulse wave detecting device for detecting a pulse wave by use of an ultrasonic wave, in order to prevent attenuation of the ultrasonic wave caused by a gap formed between the pulse wave detecting device and the user's skin, a transmitter for generating an ultrasonic wave and a receiver are formed on a support substrate so as to protrude therefrom. Consequently, the transmitter and receiver contact a surface of the skin and no gap is formed between the surface of the skin and the pulse wave detecting device. A pulse wave detecting device high in detection accuracy is thus realized without the need for applying a gel between the skin and a detecting surface of the device.

Abstract: A blood vessel imaging system includes a measuring light source which emits a measuring light beam. An optical heterodyne detection system consists of an optical system which splits the measuring light beam into a first light beam traveling to impinge upon an organism and a second light beam traveling not to impinge upon the organism and combines the second light beam with the first beam emanating from the organism into a combined light beam, a frequency shifter which causes the first and second light beams to have frequencies different from each other, and a beat component detector which detects beat components of the combined light beam. A band-pass filter detects, out of the beat component detection signal output from the beat component detector, off-centered components in a frequency band deviated from the center frequency of the beat component detection signal by a predetermined width.

Abstract: The invention relates to a measuring device (102) carried by a user during exercise for measuring non-invasively at least one signal from the body, e.g. a wireless heart rate monitor, and to a method of controlling same. The measuring device comprises a user interface (120). The user interface comprises selection means (114), e.g. push buttons (114), and display means (116, 122), e.g. a liquid crystal display. The user interface (116) displays different operating modes, e.g. a watch mode (300), a set mode (306) and an operating mode (302) for measuring a signal from the body. The operating modes are arranged as a main loop sequence (300-302-304-306). The operating modes have different sub-operating modes for displaying parameters associated with exercising. The sub-operating modes are arranged as sub-loop sequences (400-404-406-410) under each operating mode. In accordance with the invention, the user is able to configure the sub-loop sequence (400-404-406-410) by the selection means (114).

Abstract: There is provided a pulse wave detecting apparatus capable of clearly discriminating pulsations from noise having a small storage amount and also a small computation amount. In the pulse wave detecting apparatus, while an oscillator unit transmits ultrasonic waves toward an object under examination and a receiver receives reflection waves reflected from the object under examination, a detecting unit converts the reflection waves from the pulse waves. A pulsation detecting unit predicts timing of a next pulsation from an interval of previously acquired pulsation and pulse, detects a peak of a pulse wave which is larger than a predetermined value within the zone Z located before/after the predicted timing of the pulsation. Then, this pulsation detecting unit specifies such a peak having a timing which is located at the nearest timing with respect to the predicted timing among each of these peaks.

Abstract: A heart rate measurement arrangement wherein the heart rate measurement arrangement comprises a calculating unit comprising a mathematical model arranged to form a person's energy metabolism level as an output parameter of the model using as input parameters of the model one or more heart rate parameters and one or more physiological parameters each describing a physiological characteristic of the person, the heart rate measurement arrangement further comprising display means for displaying information formed in the calculating unit.

Abstract: An earring that flashes in synchronism with the wearer's heartbeat. A pulsed IR LED/photocell combination is built into an earring along with a comparator and a visible light-emitting source. The comparator determines when the heart has beat from the variation in the signal from the photocell and transmits a signal to a solid state switch to turn on the visible light-emitting source. Thus, the light emitting source flashes once for each heart beat. In a preferred use of the present invention a lover is able to determine when his or her partner is excited by observing the rate at which the partner's earring flashes. The invention may also be used for medical monitoring of patients.

Abstract: The test subject attaches pulse wave detectors 1 to his fingertips, and presses down on pressure sensor 110. As a result, CPU 4 determines the DC component of the received light signal LS, and stores this in calibration table 50 in association with the pressure level. Subsequently, CPU 4 calculates threshold values, which can be used for grading the touch sensation, based on maximum value Pmax of the pressure level and calibration table 50, and stores this result in threshold table 51. When the subject grips an object with his fingers, the blood flow volume is detected by pulse wave detector 1 as received light signal LS. CPU 4 calculates the DC component of received light signal LS, compares this result to the threshold values stored in threshold value table 51, generates touch information SJ, and displays this on LCD 108. Accordingly, in this case, pulse diagnosis can be easily performed by expressing the degree of pressure in the pulse diagnosis as touch information SJ.

Abstract: A method and a pulse pressure sensor for sensing an arterial pulse pressure waveform. In one embodiment, the pulse pressure sensor includes a housing, a diaphragm, a piezoelectric device, and a self-contained amplifier. The skin-contact diaphragm is attached across a recess or opening in the housing. The piezoelectric device has a first portion mounted in a fixed relationship to the housing and a second portion displacementally coupled to the diaphragm. The solid-state amplifier has a signal input coupled to the piezoelectric device, wherein the piezoelectric device and amplifier together have a frequency response at least including a range from below approximately 0.1 hertz to above approximately 250 hertz. In one such embodiment, the housing and the skin-contact diaphragm of the sensor are stainless steel. In one such embodiment, the diaphragm has a skin-contact surface with a skin-contact dimension of between approximately 0.4 inch and 0.6 inch.

Abstract: A sensor holding and positioning device. In one embodiment, the device includes a sensor base having two feet, the base forming a raised bridge between the two feet. The bridge has one or more cross members spanning all or part of the space between the two feet. A sensor suspension including a sensor holder and sensor-height-adjustment mechanism is coupled by a pivot-arm axle to the sensor base, such that the sensor suspension is able to rotate in an arc about the long axis of the axle. In one such embodiment, the device further includes a pressure sensor attached to the sensor holder of the sensor suspension. In another such embodiment, the sensor suspension is able to slide back and forth along a line parallel to the long axis of the axle. Another aspect is for positioning the sensor over the radial artery, for example in a human's wrist. Yet another aspect is a pulse-waveform acquisition system.

Abstract: A pulse counter is provided in which the value displayed for the detected value is highly reliable. An SN condition detecting means detects the SN condition of a pulse wave signal (step S201). The SN condition detecting means then determines whether or not the detected SN condition is good based on a specific threshold value (step S202). When a determination is made that the SN condition is good, a display control signal to display the pulse rate on a display means is output to a display method switching means (step S203). Conversely, when a determination is made in step S202 that the SN condition is not good, the pulse rate is not displayed on the display means, but rather a display control signal indicating that no information at all be displayed is output to the display method switching means (step S204).

Abstract: A pulsimeter analyzes a pulse wave signal output by a pulse wave sensor worn on a part of the body while exercising, enables extraction of only the pulse wave component without being affected by movement of the body, and evaluates a detection state indicative of whether the pulse wave sensor is detecting the pulse. A pulse wave component extractor extracts a pulse wave component from the result of a time-frequency analysis of a pulse wave signal. A pulse rate calculator calculates the pulse rate per minute based on the pulse wave component extracted by the pulse wave component extractor. The pulse rate is then displayed. A detection state of the pulse wave sensor is also displayed by providing a detection state evaluator for determining the presence of a pulse wave component based on the result output by the pulse wave component extractor.

Abstract: A method and an apparatus to analyze two measured signals that are modeled as containing desired and undesired portions such as noise, FM and AM modulation. Coefficients relate the two signals according to a model defined in accordance with the present invention. In one embodiment, a transformation is used to evaluate a ratio of the two measured signals in order to find appropriate coefficients. The measured signals are then fed into a signal scrubber which uses the coefficients to remove the unwanted portions. The signal scrubbing is performed in either the time domain or in the frequency domain. The method and apparatus are particularly advantageous to blood oximetry and pulserate measurements. In another embodiment, an estimate of the pulserate is obtained by applying a set of rules to a spectral transform of the scrubbed signal. In another embodiment, an estimate of the pulserate is obtained by transforming the scrubbed signal from a first spectral domain into a second spectral domain.

Abstract: An organism information measuring method and an arm wear type pulse-wave measuring method having a sensor unit having a size that does not cause any inconvenience to a user when the user is doing an exercise, such as jogging, so that information about an organism, such as the pulse rate, is measured. The arm wear type pulse-wave measuring apparatus has a wrist band for putting the body of the apparatus on the arm; and a sensor unit that is put on the root of a finger by a sensor securing band. If the finger is irradiated with light by a LED in the foregoing state, light reaches the blood vessel and is reflected. The reflected light is received by a phototransistor in such a manner that the quantity of received light corresponds to change in the quantity of blood occurring due to pulse waves of the blood. The LED is of a type capable of emitting blue light and has a light emission wavelength peak of 450 nm. The phototransistor has a light receiving wavelength region in a range from 300 nm to 600 nm.

Abstract: A convenient low-cost heart rate monitor. In one embodiment, a digital filter structure includes a low pass filter having a notch at 60 Hz and a bandpass filter which amplifies signals in a frequency range from 10-40 Hz and has a notch at 60 Hz. This digital filter has a recursive structure and uses integer coefficients to simplify and speed up the calculations. A four bit microcontroller may implement the digital filter. The output of the digital filter is subject to enhancement signal processing to emphasize QRS complexes indicative of human heartbeats.

Abstract: The present invention provides an diagnostic apparatus and method for physiologically measuring the biological responses of a selected group of muscles during exercise. Biological responses measured include blood flow, blood pressure, transcutaneous oxygen, and lymphatic clearance rate. The apparatus comprises a pressure plate attached to an axle. A spring mechanism is attached to the pressure plate to bias the plate towards the resting position. The spring may be adjusted so as to increase the resistance to the group of muscles being exercised and induce fatigue.

Abstract: In accordance with the present invention, a transmittance pulse oximeter sensor having an emitter that is offset from the detector. Offsetting the emitter and detector allows more light to pass through a thin tissue pulsating arterial bed than does a vertically aligned design. The offset between the emitter and the detector increases the effective arterial blood component without increasing artifact. Thus, the arterial blood component strength relative to the artifact strength is increased resulting in an improved signal and an improved pulse oximetry reading. The offset pulse oximetry sensor is especially important in veterinary pulse oximeter applications where it is necessary to monitor small animals whose optimal pulse oximetry location is a thin tissue tongue. The offset pulse oximetry sensor is additionally important in the realm of human medicine where often the optimal position for a pulse oximeter sensor is a thin tissue ear or an infant's thin tissue finger or toe.

Abstract: For the purpose of realizing a display method for a portable electronic measuring device that allows the user to know his condition more easily and in greater detail by making it easy for him to read the display of measured results even if the display device is limited in size due to its portability, a bar graph is displayed in dot display area (134) of liquid crystal display device (13) of the portable pulse measuring device which extends up at each time interval according to the absolute value of the pulse rate after the measurement of time is started and until the pulse rate reaches a prescribed range, and after the pulse rate reaches the prescribed range, a bar graph is displayed that extends in the positive direction or the negative direction at each time interval according to the difference from the prescribed reference pulse rate. When temporal changes in the pitch during running are displayed in dot display area (134), they are displayed in a segmented graph.

Abstract: To achieve a pulse wave measuring apparatus whereby the sensor unit can be easily and consistently worn against the skin surface, a wristwatch type pulse wave measuring apparatus is comprised as follows. Specifically, light transmittance plate 34 is disposed on the outside surface side of LED 31 and phototransistor 32 in sensor unit 30. Outside surface 341 of light transmittance plate 34, which is pressed against the finger, projects above the reference surface, which is outside surface 361 of sensor frame 36 surrounding light transmittance plate 34. Two body ground terminals 38 contacting the finger surface when light transmittance plate 34 is pressed tight to the finger are disposed around light transmittance plate 34; the body ground terminals 38 also project above the reference surface. However, the position of outside surfaces 381 of body ground terminals 38 is lower than the outside surface 341 of light transmittance plate 34.

Abstract: The invention provides a wrist-worn pulse wave measuring device capable of outputting data measured by the wrist-worn pulse wave measuring device to an external data processing device without using a large device body. In the pulse information processing apparatus, a connector piece of a sensor unit is mounted to a connector of a wrist-worn pulse wave measuring device when measuring the pulse. A data transmission connector piece is mounted to the connector of the pulse wave measuring device when transmitting data with a data processor. Whether the operating mode is the pulse measurement mode or the data transmission mode is determined by a signal discriminator which discriminates the signal input from the connector of the pulse wave measuring device.

Abstract: An apparatus for detecting a pressure pulse wave from a living subject, including a pressure pulse wave sensor which detects a pressure pulse wave which is produced from an artery of the subject, a pressing device which presses the sensor against the artery via a body surface of the subject, a position changing device which moves the sensor and thereby changes a position of the sensor relative to the artery in a direction of width of the artery, and a control device which determines, based on the pulse wave detected by the sensor, an optimum pressing position of the sensor where the sensor is pressed against the artery by the pressing device, and controls the position changing device to position the sensor at the optimum pressing position, the control device functioning as a moving device for controlling the position changing device to move the sensor relative to the artery while the sensor is pressed on the body surface by the pressing device, a determining device for determining the optimum pressing positio

Abstract: For the purpose of providing, by only improving the shape of the device body, at a low cost and without impairing user comfort a wrist-worn portable device and a wrist-worn pulse wave measuring device whereby the device body does not turn unnecessarily around the wrist. A wrist-worn pulse wave measuring device 1 attaches device body 10 by means of wrist band 12 to the wrist, and attaches sensor unit 30 to the base of a finger by means of a band for holding the sensor. At the end of cable 20 leading from sensor unit 30 is formed connector piece 80, which is attached by simply sliding connector 70 in the direction of twelve o'clock. Because device body 10 has a turning stop 108 forming an approximately 115.degree. angle to the back, device body 10 will not turn unnecessarily even if it is turned in the direction of six o'clock or twelve o'clock on a wristwatch.