Abstract: There is provided an ultrasound system for forming strain images by decreasing decorrelation of receive signals, which vary with time or space. More specifically, the decorrelation between the receive signals obtained without and with applying stress to a target object is reduced to decrease an error, which occurs during the calculation of a delay. Also, a center frequency, which varies with depth of a target object, is compensated to form the strain image.

Abstract: The invention relates to a device (1) for determining the blood volume and/or blood volumetric flow of a circulation section, comprising a fluid storage unit (2) for storing a measuring fluid (3), an injection device for the injection of the measuring fluid into the circulatory system, at least one pump device (5) disposed between the fluid storage unit and the injection device, means for determining at least one property of the measuring fluid before injection into the circulatory system, further means for determining the respective properties in the circulatory system downstream of the injection site, and an analysis device for calculating the blood volume or volumetric flow as a function of the properties determined. The invention further relates to such a device having means for conditioning the measuring fluid.

Abstract: A system and method (1000) for an interactive game is disclosed herein. The system (1000) preferably includes monitoring device (20) monitoring the vital signs of a user, an interface (1115), a game console (1010) and an accessory (1020). The monitoring device (20) is preferably an article (25) having an optical sensor (30) and a circuitry assembly (35), and a pair of straps (26a and 26b). The monitoring device (20) preferably provides for the display of the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; distance traveled; and/or dynamic blood pressure. The article (25) is preferably a band worn on a user's wrist, arm or ankle.

Abstract: A system and method (1000) for an interactive game is disclosed herein. The system (1000) preferably includes monitoring device (20) monitoring the vital signs of a user, an interface (1115), a game console (1010) and an accessory (1020). The monitoring device (20) is preferably an article (25) having an optical sensor (30) and a circuitry assembly (35), and a pair of straps (26a and 26b). The monitoring device (20) preferably provides for the display of the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; distance traveled; and/or dynamic blood pressure. The article (25) is preferably a band worn on a user's wrist, arm or ankle.

Abstract: A method of estimating blood flow in the brain, comprising: a) causing currents to flow inside the head by producing electric fields inside the head; b) measuring at least changes in the electric fields and the currents; and c) estimating changes in the blood volume of the head, using the measurements of the electric fields and the currents.

Abstract: A pulse rate sensor that includes an accelerometer for measuring periodic motion and a piezo sensor for detecting erratic motion is capable of more accurately determining pulse rate by accounting for these types of motion. The pulse rate sensor in accordance with the present invention diminishes pulse rate signal degradation due to erratic motion through a combination of algorithms that control signal boosting, waveform refinement and signal noise suppression.

Abstract: Blood analysis is carried out using a portable video camera with an objective lens, by placing the video camera such that the objective lens is completely obstructed, at least partly by at least part of an appendage forming part of an individual, and operating the video camera. The image signals from the video camera are then analysed to deduce information about blood flow in the appendage. This information may concern blood flow (e.g. pulse rate) or blood constituents. The video camera may form part of a mobile phone, and the objective lens may be completely obstructed by a fingertip. The resulting data may be displayed in real-time on the mobile phone.

Abstract: A method of diagnosis is disclosed. The method comprises: acquiring an absolute component and a phase component of an input signal indicative of an impedance of an organ of a subject; determining baseline blood flow of the subject based on the phase component; determining transient changes in blood flow based on at least the absolute component; and displaying the baseline blood flow and the transient changes in blood flow.

Abstract: A device for and a method of measuring a blood flow of a living body having blood vessels that emit bio-photons and through which blood flows, the device including a detector positioned adjacent to a predetermined portion of the living body for measuring a bio-photon emission from the living body and a processor for analyzing and displaying the blood flow of the living body based on a value of the bio-photon emission.

Abstract: A hypovolemia monitor comprises a plethysmograph input responsive to light intensity after absorption by fleshy tissue. A measurement of respiration-induced variation in the input is made. The measurement is normalized and converted into a hypovolemia parameter. An audible or visual indication of hypovolemia is provided, based upon the hypovolemia parameter.

Abstract: Many people do not have a physical feeling for what normal and abnormal blood pressure levels mean in relation to the forces exerted on the heart and blood vessels. A blood pressure simulation apparatus provides human subjects a means to physically feel simulated blood pressure levels through tactile feedback. Both normal and abnormal blood pressure cycles are simulated. Interfacing of the apparatus to an electronic blood pressure monitor is provided.

Abstract: Devices and methods for detecting inadequate tissue perfusion by measuring a parameter other than heart rate such as vascular blood pressure, intracardiac blood pressure, vascular blood flow or tissue perfusion, in addition to or as a substitute for heart rate. Such devices and methods improve the accuracy of determining when and to what degree therapy should be administered to treat inadequate tissue perfusion, such as pre-syncope, syncope, or orthostatic hypotension, particularly in the absence of abnormal cardiac function.

Abstract: Detection of volume depletion, particularly after an incidence of volume overload is disclosed. Various methods, systems, and devices are disclosed that sense and analyze a physiological parameter related to a patient's fluid level in order to warn patients of potentially dangerous volume depletion conditions while minimizing false notifications.

Abstract: A blood rheology measuring apparatus has a measuring portion for measuring a flow velocity of the blood flowing in a blood vessel of a person in a mode of a Doppler shift signal by transmitting and receiving a wave to and from a surface of the person's skin. An information processing portion calculates an intensity at each of frequency components of the Doppler shift signal, extracts a maximum frequency in a signal at an intensity level equal to or larger than a threshold in the histogram or a maximum frequency when an integrated value from a low frequency component reaches a predetermined rate of a total thereof in the histogram, and provides a temporal change waveform of the extracted frequency. The blood rheology is analyzed based on the maximum frequency in the frequency waveform.

Abstract: A noninvasive photoplethysmographic sensor platform for small animals provides a spring biased sensor clip, wherein at least one side of the sensor clip is provided with a saddle faced clip face member. The saddle shape of the clip face member may have a hinge end, toward the hinge of the clip, which is longer in the longitudinal direction of the clip and shorter in depth than the distal end. The shorter distal end side (measured longitudinally) of this saddle shape facilitates the ability to align the transmitted and received light with the bone, while the overall saddle shape of the facing provides a physical grip to capture enough tissue to prevent the clip from relocating over time while it is attached to the limb. The shorter hinge end side (depth-wise) also allows the clip to close when it is fully assembled. The edges of the saddle shaped clip are preferably rounded off to prevent the contusions of the tissue that may result from long-term contact.

Abstract: According to one embodiment, a blood flow perfusion analyzing apparatus includes tissue and arterial TCC calculation units, first and second making units, a deconvolution unit and a blood flow information calculation unit. The tissue TCC calculation unit obtains tissue TCCs. The arterial TCC calculation unit calculates an arterial TCC. The first making, unit makes first sets, starting from a first time in which elements corresponding to the tissue are arrayed one-dimensionally, based on the tissue TCCs. The second making unit makes a second set, starting from a second time after the first time, in which elements corresponding to the artery are arrayed two-dimensionally, based on the arterial TCC. The deconvolution unit calculates transfer functions of the tissue based on the first and second sets. The blood flow information calculation unit calculates information on a blood flow perfusion based on the transfer functions.

Abstract: A method of deriving blood perfusion indices for a region of interest (ROI) of a subject, comprising the steps of administering a contrast agent to the subject during a dynamic imaging scan, converting signal intensity data from raw images of the scan into contrast agent concentration data, deriving parameters from the contrast agent concentration data using at least one transport function that accounts for delay and dispersion of the contrast agent, and calculating the blood perfusion indices from the derived parameters.

Abstract: The present invention provides a system and method for estimating a blood flow waveform contour from a pressure signal. An arterial or ventricular pressure signal is acquired from a pressure sensor. Landmark points are identified on the pressure waveform that correspond to features of a flow waveform. In one embodiment, the landmark pressure waveform points correspond to the onset of flow, the peak flow, and the end of the systolic ejection phase. The landmark pressure waveform points define a contour that approximates the flow contour. Beat-by-beat flow contour estimation can be performed to allow computation of flow-related hemodynamic parameters such as stroke volume or cardiac output for use in patient monitoring and/or therapy management.

Abstract: A light-emitting sensor device is provided with: a substrate (110); an irradiating part (120), disposed on the substrate, for applying light to a specimen; a light receiving part (150), disposed on the substrate, for detecting light from the specimen caused by the applied light; a light scattering part, disposed at least one of between the irradiating part and the specimen and between the specimen and the light receiving part, for scattering at least one of light emitted from the irradiating part and the light from the specimen. By this, it is possible to stably detect a predetermined type of information, such as a blood flow velocity, on the specimen.

Abstract: For delivery of a chemical to a target region of a subject's brain, an apparatus comprising a storage medium on which is stored digital representations of subject-specific selective visual stimuli that, when viewed, selectively stimulate blood flow to the target area of the brain; and an electronic display device coupled thereto and configured for converting the stored digital representations to images viewable by the subject; wherein the one or more selective visual stimuli were determined by exposing the subject to a plurality of potential stimuli; measuring the blood flow response to multiple regions of the brain, including the target area and one or more non-target areas; comparing the blood flow responses to the potential stimuli, and selecting as selective stimuli potential stimuli that result in relatively more blood flow to the target area and relatively less blood flow one or more non-target areas.

Abstract: Systems and methods provide for assessing a patient's hemodynamic response to a drug therapy. A patient's hemodynamic response to a drug therapy is monitored using sensor data acquired using one or more sensors. The patient's hemodynamic response to the drug therapy is quantified, such as by quantifying a patient's sensitivity or refractoriness to the drug therapy. The quantified data may be used to optimize a patient's drug therapy, among other uses.

Abstract: The apparatus for assessing the risk of cerebrovascular diseases comprises a sensor part 1, a circuit part 2, a computation part 3 and an output part 4, where the circuit part 2 is a functional part for driving the sensor part 1 and transmitting a signal detected at the sensor part 1 to the computation part 3 and comprises a transmission circuit 21, a first receiving circuit 22, a second receiving circuit 23 and the like. The transmission circuit 21 is in connection with a transmission device 111 and a transmission device 121, for driving these devices to generate a continuous wave. A rate wave form computation part 31 is in connection with the first receiving circuit 22 and the second receiving circuit 23 to obtain the frequency of the reflected continuous wave as detected with the receiving units 112 and 122. Comparing the frequency with the frequency from the transmission circuit 21, the variation of the frequency is detected. Based on these values, blood flow rate “v” can be determined.

Abstract: Methods, systems and devices are provided for reducing the amount of data, processing and/or power required to analyze hemodynamic signals such as photoplethysmography (PPG) signals, pressure signals, and impedance signals. In response to detecting a specific event associated with a cyclical body function, a hemodynamic signal is continuously sampled during a window following the detecting of the specific event, wherein the window is shorter than a cycle associated with the cyclical body function. The hemodynamic signal is then analyzed based on the plurality of samples.

Abstract: The present invention provides methods and devices for performing flow cytometry. In one embodiment, blood circulating through one or more retinal blood vessels of a subject is illuminated in-vivo so as to excite a plurality of fluorescent-labeled cells contained in the blood. The fluorescence radiation emitted by the excited cells is then detected and analyzed to count the cells from which fluorescence is detected.

Abstract: In order to supply a method and a device that can evaluate the fluidity of blood with good sensitivity in a simple manner, there is provided a blood fluidity evaluation method in which a pressure member is pressed against a test site upon a test subject, blood at the test site is squeezed to flow out to the periphery of the test site, change over time of the amount of blood at the test site is measured at this time using optical scattering, and blood fluidity at the test site is evaluated from this measurement data; and, desirably, before the above method, a positioning process is performed in which: the pressure member is pressed against the test site with a weak force; pulse measurement data is acquired due to the absorption of light; and a relative position, at which the intensity of the pulse measurement data attains a local maximum, is determined as being an optimum measurement position.

Abstract: A method and system are disclosed for evaluating symptomatic vertebrobasilar disease VBD which uses quantitative hemodynamic assessment in order to identify patients at high risk for stroke and provide appropriate guidance for intervention. Patients with symptomatic VBD may be considered for intervention to provide blood flow augmentation if evidence of sufficient flow compromise is present as defined by specific flow criteria, and treated medically otherwise.

Abstract: Embodiments of the present invention are directed to a physiological monitoring device which is configured to record signals that reflect blood flow and/or blood pressure, and which may also record ECG signals. In one embodiment, a portable monitoring device comprises a plurality of impedance electrodes configured to be coupled to a patient's body and to generate an AC current with an electrical field to detect local electrical impedance of a portion of the patient's body encompassed by the electrical field, the local electrical impedance being a surrogate measure of local blood flow of the portion of the patient's body. At least a portion of the portable monitoring device is configured to be insertable subcutaneously into the patient's body.

Abstract: A system and method (1000) for an interactive game is disclosed herein. The system (1000) preferably includes monitoring device (20) monitoring the vital signs of a user, an interface (1115), a game console (1010) and an accessory (1020). The monitoring device (20) is preferably an article (25) having an optical sensor (30) and a circuitry assembly (35), and a pair of straps (26a and 26b). The monitoring device (20) preferably provides for the display of the following information about the user: pulse rate; blood oxygenation levels; calories expended by the user of a pre-set time period; target zones of activity; time; distance traveled; and/or dynamic blood pressure. The article (25) is preferably a band worn on a user's wrist, arm or ankle.

Abstract: The difference in time that it takes for blood to flow to two locations in a patient's body can be measured by placing, on the patient's body, sensors for non-invasively detecting a variable characteristic of the content of the blood at each of those locations. The time of occurrence of a change in that characteristic as detected by one of the sensors is compared to the time of occurrence of that same change as detected by the other sensor. The difference between these two times is a measure of the difference in time that it takes for blood to flow to the locations of the two sensors.

Abstract: A method for the quantitative representation of the blood flow in a tissue or vascular region is based on the signal of a contrast agent injected into the blood. In the method, several individual images of the signal emitted by the tissue or vascular region are recorded at successive points in time and are stored. Based on the respective signal, a quantity characteristic for the blood flow and a quantity characteristic for the position of the blood vessels are determined for image areas of individual images. These quantities are represented superimposed for the respective image areas such that both the blood flow quantity and the position of the fine blood vessels become clearly visible in the representation and can be differentiated from the tissue.

Abstract: A method for measuring blood flow velocity comprises the steps of: placing a first and second blood vessel signal detectors on a body of a person to be measured in such a manner that the first and second blood vessel signal detectors are located a predetermined distance from each other; using the first and second blood vessel signal analyzers to record the blood signal at a predetermined time interval; setting an interval of time from the moment a specific blood vessel signal appears in a record of the first blood vessel signal analyzer to the moment the specific blood vessel signal appears in a record of the second blood vessel signal analyzer to be a predetermined time period; and dividing a value of the predetermined distance by a value of the predetermined time period can get a blood flow velocity.

Abstract: There is provided a method of processing an ultrasound spectrum image. According to such method, a spectrum image is formed based on ultrasound data and then the noise is removed from the spectrum image. The noise-removed spectrum image is matched with one or more spectrum models representing specific spectrum types. Then, whether or not the noise-removed spectrum image contains an aliasing is checked. If the noise-removed spectrum image contains the aliasing, then the aliasing is removed from the noise-removed spectrum image to provide a noise-removed spectrum image without the aliasing. Thereafter, contour tracing is performed on the noise-removed spectrum image without the aliasing to detect contour points. Further, peak tracing is performed on the noise-removed spectrum image without the aliasing to detect peaks.

Abstract: In a method and device for detecting the intake of food in a subject at least one parameter related to the blood flow and/or perfusion of a blood vessel and/or an organ in the digestive system of a patient is monitored by a sensor attached to, or in, a blood vessel or organ of the digestive system. The value of each monitored parameter is analyzed and may be used to control the activity of a gastric stimulator.

Abstract: The present disclosure relates to determining a patient's disease state based at least in pail on obtaining or determining certain underlying characteristics, such as vasotone, venous compliance, or ability of the vascular system to drain venous blood, of the patient's vascular system. The characteristics may be obtained by analyzing changes to a patient signal, such as the overall signal change, the rate of change, the shape of the change, changes in signal energy, or changes in the baseline and/or the amplitude of the signal, and/or the time period(s) over which the signal changes, that are caused by inducing a load on the vascular system. In some embodiments, the signal changes may be analyzed by transforming the signal using, for example, a continuous wavelet transform. The patient's health status or disease state may be determined using the one or more vascular system characteristics that influenced the signal change.

Abstract: A heart monitor is disclosed including an electroacoustic transducer such as an earphone coupled to a controller. The transducer is positioned in a person's ear in acoustic communication with the tympanum. Signals from the transducer are processed to determine the presence of pulsatile blood flow. The heart monitor may be incorporated into a defibrillator to sense the presence of blood flow for use in a shock delivery decision.

Abstract: Methods and systems for monitoring an organ of interest within a patient use one or more sensors to obtain one or more signals indicative of one or more of blood being provided to the organ of interest, blood being received from the organ of interest, and blood present in the organ of interest. Changes in an amount of blood being provided to the organ of interest, an amount of blood being received from the organ of interest, and/or an amount of blood present in the organ of interest are monitored based on changes in the obtained signal(s). Such methods and systems can be used to detect dysfunction of the organ of interest or tumor growth in the organ of interest, but are not limited thereto.

Abstract: The present invention provides a method for acquiring personal identification data by extracting a ridge-and-recess pattern corresponding to a fingerprint or a knuckle joint and lines on a palm by utilizing characteristics by which subcutaneous bloodstream distribution is spatially modulated by the ridge-and-recess pattern on the surface when measuring a subcutaneous bloodstream distribution based on a bloodstream measuring technology utilizing laser scattering, and by acquiring the same as personal identification data based on living body information, and the same method for acquiring personal identification data includes the steps of: irradiating a laser beam onto at least a part of a fingertip surface or a palm; imaging reflection light from subcutaneous blood vessel layers at an irradiation spot to which a laser beam is irradiated by receiving the same on an image sensor as laser speckles; calculating a change ratio of a light-receiving amount at respective pixels of the laser speckles; preparing a two-di

Abstract: An inventive method and system are provided for identifying a compatible photoplethysmographic sensor when interconnected to a given photoplethysmographic monitor. The method and system may further provide for the identification of which of a plurality of compatible sensors is interconnected to allow for selective calibration of the photoplethysmographic monitor. In this regard, the system and method may entail provision of a predetermined drive or test signal to a light source and/or identification element (i.e., sensor elements) of a photoplethysmographic sensor, and the obtainment of a corresponding output signal for use in sensor identification. In one approach, an output signal is obtained from at least one of three sensor elements each of which is interconnected between a different pair of sensor terminals which is a unique combination of two of four sensor terminals on the sensor.

Abstract: According to embodiments, a wavelet transform ratio surface measure signal may be generated from two PPG signals. Values of the wavelet transform ratio surface measure signal at a given moment of time (i.e., instantaneous values) may be indicative of localized signal discrepancies within and/or between the PPG signals such as noise and signal artifacts. Spikes in the instantaneous values of the wavelet transform ratio surface measure signal may be located and used to determine a signal quality measure for the PPG signals. Characteristics of the spikes such as number, location, grouping, distribution, amplitude, and polarity may be used in the signal quality determination.

Abstract: A system and plethysmographic test procedure for evaluating venous blood volume/flow at a subject's legs. Occluding and sensing cuffs mounted to a subject's thighs and calves/ankles are inflated and deflated relative to controlled movement of a supporting chair. The chair provides hinged backrest, seat and footrest pieces and is controlled to manipulate the subject during several test phases as blood volume/flow is monitored. The chair is manipulated between a 1) baseline calibration position with the subject's back upright, seat horizontal to floor and feet lowered, 2) an outflow position with the subject's back tipped back flat and legs elevated above the heart, 3) a dependent filling position, rapid return of subject to back upright, seat horizontal to floor and feet lowered, and 4) an exercise position wherein the ankles are flexed with the back upright, seat horizontal to the floor and feet lowered.

Abstract: The present invention is related to a spectrum analytical method for quantifying hear-lung interaction, which can estimate cardiac function by using a heart-associated monitoring signal. According to the method of the present invention, quantification of heart-lung interaction is conducted by choosing spectrum signals within a specified frequency band, such that the interference to the heart-associated monitoring signals by incidental events occurring at a low frequency, can be avoided. Therefore, the method of the present invention can be performed even in the subjects who are not in a state of general anesthesia or sedation, and hence is very useful in estimating the cardiac function of the test subjects.

Abstract: Embodiments of the present invention relate to a system and method for in vivo measurement of blood parameters by processing analog electrical signals from a plurality of photodetectors. In some embodiments, it is possible to determine one or more blood parameters according to (i) a first electrical signal from a first detector and (ii) a second electrical signal from a second photodetector. A difference analog electrical signal is generated, indicative of a difference between the light response signal at the first location and light response signal at the second location, is generated. One or more blood parameters may be detected according to the difference analog electrical signal.

Abstract: [Subject] To provide laser Doppler blood flow measuring method and device which achieve multi-dimensional measurement efficiently at a high degree of accuracy over a wide range with a simple optical system and device. [Solving Means] Laser light from a semiconductor laser 12 is split and formed into sheet lights Ls using a cylindrical lens 22, and the sheet lights Ls are crossed with each other at a predetermined position. A lens system 30 configured to form an image of scattered lights into a linear shape at a linear irradiation site Lx where the sheet lights Ls cross with each other is provided. An optical fiber array 32 having a plurality of optical fibers 34 is provided at an image-forming position of the lens system 30. Avalanche photodiodes 42 configured to convert the scattered lights which are shifted in frequency by the Doppler effect caused by the blood flow into electric signals for the each optical fiber 34 are provided.

Abstract: The present invention relates to a noninvasive medical pulsimeter sensor using magnetic thin films. By forming a pulse-sensing part array with magnetic sensors such as GMR devices, MTJ devices and the likes, over the skin-contacting part which consists of a magnetic material, the present invention increases the integrity of sensors, minimizes the time for searching the pulse and it is applicable widely to portable pulsimeters and the likes.

Abstract: A method and apparatus for improving the diagnostic performance of a probe system (30) for detecting a medical condition in a patient by sensing volume changes in a monitored body part due to pulsatile arterial blood flow in the body part, characterized in calibrating the probe system (30) for the respective measurement site according to a predetermined characteristic of the monitored body part of the patient and quantifying the arterial pulsatile volume thereat. Such calibration is described with respect to probes including: (1) a pressure sensor (63), which senses pressure changes in a compressible fluid system to which the patient's body part (e.g.

Abstract: A system including an implantable neurostimulator device capable of modulating cerebral blood flow to treat epilepsy and other neurological disorders. In one embodiment, the system is capable of modulating cerebral blood flow (also referred to as cerebral perfusion) in response to measurements and other observed conditions. Perfusion may be increased or decreased by systems and methods according to the invention as clinically required.

Abstract: A cuff of a pulse wave meter equipped with an arteriosclerosis degree judgment device has air bags for compressing a living body having a double structure along an artery including an avascularization air bag and a pulse-wave measuring air bag. Provided at outer circumferential sides of these air bags are a curler for integrally pressing these air bags against an upper arm, and an air bag for pressing the curler from the outer circumferential side. A member for suppressing vibrations is provided between a curler-compressing air bag and the pulse-wave measuring air bag, and suppresses propagation of vibrations from the curler-compressing air bag to the pulse-wave measuring air bag. The pulse wave meter measures a pulse wave based on changes in internal pressure in the pulse-wave measuring air bag while the avascularization air bag provides avascularization at the peripheral side.

Abstract: A method and apparatus for assessment of hemodynamic and functional state of the brain is disclosed. In one embodiment, the method and apparatus includes non-invasive measurement of intracranial pressure, assessment of the brain's electrical activity, and measurement of cerebral blood flow. In some embodiments, the method and apparatus include measuring the volume change in the intracranial vessels with a near-infrared spectroscopy or other optical method, measuring the volume change in the intracranial vessels with rheoencephalography or other electrical method, and measuring the brain's electrical activity using electroencephalography.

Abstract: A method, apparatus and software program for measuring a parameter relating to the heart-lung system of a mammal are described. The method, software and apparatus can be implemented in a dialysis or other blood treatment apparatus comprising an extracorporeal blood circuit connected to a mammal; the circuit comprises a dialyzer, or other treatment unit, having a blood inlet, a blood outlet, a treatment fluid inlet and a treatment fluid outlet. The method comprises the steps of providing a pulse of a detectable substance in the blood circuit, measuring an integrated concentration of the detectable substance on the dialysis fluid outlet, determining the parameter based on the measurements on the dialysis fluid outlet.

Abstract: A heart rate variability measurement method is revealed. The method includes the following steps. At first, play a piece of music for a participant. Then detect a change in vascular volume of the participant. Next depict a continuous waveform signal of the change in vascular volume. Thus while measuring the heart rate as well as heart rate variability, the participant is not easy to get nervous or impatient and the real heart rate as well as heart rate variability can be obtained, without being affected by the mood. Therefore, the accuracy of the heart rate variability during measurement is increased.