Abstract: An optical vital signs sensor configured to measure or determine vital signs of a user comprises a light source configured to generate a light beam having an angular range of angles of incidence. The light beam is directed towards the skin of the user. A photo detector is provided and is configured to detect light which is indicative of a reflection of the light beam from the light source in or from the skin of the user. The light source and the photo detector are arranged adjacent to each other and on the same side of the skin of the user. A light shaping unit is configured to shape the light beam of the light source before the light beam enters the skin by limiting the angular range of angle of incidence to less than 20°.

Abstract: A method of evaluating characteristics of a work piece includes forming a photosensitive layer on the work piece. Then an ion implantation is performed on the work piece. The work piece is radiated, and an optical intensity of the photosensitive material on the work piece is calculated. The ion implantation pattern is evaluated according to the optical intensity. A chemical structure of the photosensitive material is changed upon the ion implantation. The work piece is recovered by reversing the chemical structure of the photosensitive material or removing the ion interrupted photosensitive material by chemicals.

Abstract: A sleeve includes a body having a top opening. The body covers a handheld oximeter probe or a portion of the probe. The sleeve has a shape that approximately matches the oximeter probe or portion of the probe, which is covered by the sleeve. The sleeve has a top opening that allows a user to slide the oximeter probe into the sleeve. The sleeve is transparent to radiation emitted and collected by the oximeter probe. The sleeve is formed of a material that prevents patient tissue, fluid, viruses, bacteria, and fungus from contacting the covered portions of the oximeter probe. The sleeve leaves the probe relatively sterile after use so that little or no clearing of the probe is required for a subsequent use, such as when the probe is covered with a new, unused sleeve.

Abstract: Embodiments of the invention relate to a method and apparatus for measuring at least one parameter that is (i) descriptive of stochastic motion of suspended particles within a fluid; and/or (ii) is a rheological property of the fluid or of the suspension; (iii) describes a concentration of suspended particles within the fluid; and/or (iv) is a diffusion coefficient of the suspended particles and/or (iv) is a viscosity of the fluid or of the suspension; and/or (v) is a food aging or spoilage parameter and/or (vii) is an in-vivo or in-vitro blood coagulation parameter.

Abstract: A system for measuring the blood loss comprises a measuring device that determines the hemoglobin concentration of fluid within a container utilizing a light source and a light detector. The container receives blood and other fluids from a patient during a medical procedure. Light from the light source is passed through the blood and other fluids in the container and is detected by the light detector. Based upon a magnitude of light detected, the hemoglobin concentration of the fluid in the container can be determined. A volume-measuring device determines the volume of blood and fluid in the container. Knowing the hemoglobin concentration and volume of fluid in the container, the volume of patient blood loss in the container can be determined. The blood loss measuring device in combination with infusion systems maintains a real-blood volume status so that proper infusion of blood, crystalloid and/or colloid solutions occurs.

Abstract: A LED switching system, including a multi-chip LED including first and second sets of LED chips, the first set of LED chips associated with a first wavelength band and the second set of LED chips associated with a second wavelength band; a first LED driver in communication with the first set of LED chips; a second LED driver in communication with the second set of LED chips; a LED controller configured to: receive input indicating a selection of one of the wavelength bands; identifying one of the first set and the second set of LED chips associated with the selected wavelength band; and providing a signal to one of the first and the second LED drivers that is in communication with the identified set of LED chips; wherein, in response to the signal, the one of the first and the second LED drivers activates the identified set of LED chips.

Abstract: A fingerprint sensor device with built-in liveness detection capabilities includes: an area sensor disposed on a top surface of a substrate; a stiffener disposed below a bottom surface of the substrate; a printed circuit making electrical connection to the sensor disposed below the stiffener; and a light source and a photodetector. At least one of the light source and photodetector is disposed on the printed circuit below the area sensor. The stiffener includes at least one through-hole located with respect to the light source or photodetector to allow light from the light source to transmit through the stiffener towards a finger located on the area sensor or to allow light reflected from the finger to pass through the stiffener to the photodetector.

Abstract: A medical device includes a printed circuit board-battery assembly, a tape encapsulation assembly wrapped around the PCB-battery assembly, and a second removable tab positioned on a surface of the tape encapsulation assembly. The second removable tab provides an adhesive layer on a surface of the medical device when the second removable tab is removed from the medical device. The PCB includes the electronic circuitry that performs the functionalities of the medical device, including an optical sensor that comprises at least one light source to emit light towards a measurement site of a user and at least one photodetector to receive light returned from the measurement site. The medical device can connect to a host computing device that performs various operations, including, but not limited to, authenticating the medical device, causing measurement values such as blood oxygen saturation (SpO2), pulse rate (PR), and a perfusion index (PI) to be provided.

Abstract: Apparatus and methods provide wireless, disposable, continuous pulse oximeter sensor technology, useful and beneficial for a number of applications including relatively extended periods of data collection, and/or packaged in compact and easy-to-use assemblies. Economic fabrication and use provides flexible methodologies that can reduce the overall costs of monitoring and collecting patient's physiological data, and provide relatively greater ease and comfort to the patient. A disposable wireless continuous pulse oximeter sensor has a reduced emitter-detector separation, a low-power frontend, and a low-cost processor that sends waveforms to a host device so that the host can calculate and display the parameters of interest. Complications created by the reduced distance between emitter and detector are minimized by using an emitter-detector assembly with an optically dark background, and a bandage for improved optical compliance.

Abstract: An apparatus for measuring a biological component includes: light sources configured to emit light that irradiates a target object; one or more detectors configured to receive light from the target object that is irradiated by the light emitted by the light sources and to detect light signals corresponding to the light received from the target object; and a processor configured to determine an optimal light source for measuring a biological component, from among the light sources, based on the light signals detected by the one or more detectors and to measure a biological component of the target object using the optimal light source.

Abstract: A biological sensor capable of improving the signal to noise ratio of a detection signal obtained by a light-receiving element and amplified by an amplifier is provided. The biological sensor includes a microcontroller that generates a driving signal, a light-emitting element that emits light in accordance with the driving signal, a light-receiving element that outputs a current detection signal based on an intensity of received light, and an amplifying circuit that converts the current detection signal into a voltage detection signal, amplifies an alternating current component of the voltage detection signal, and outputs an amplified detection signal. Furthermore, the microcontroller generates an offset signal that is applied to an offset circuit to offset the direct current component of the voltage detection signal and to obtain biological information by processing the amplified detection signal.

Abstract: A pulse oximeter (1, 2) includes a first light emitter (11) configured to generate first light, a second light emitter (12) configured to generate second light with a different wavelength from that of the first light, and a light receiver (13) configured to receive each of first return light of the first light from a living body and second return light of the second light from the living body. The pulse oximeter is provided with: a contact pressure detecting device (14) configured to detect a signal associated with contact pressure between the pulse oximeter and the living body; and an outputting device (100) configured to output information regarding oxygen saturation, on the basis of respective signals outputted from the light receiver due to the first return light and the second return light, and the detected signal associated with the contact pressure.

Abstract: In some embodiments, a system comprises a head-mounted frame removably coupleable to the user's head; one or more light sources coupled to the head-mounted frame and configured to emit light with at least two different wavelengths toward a target object in an irradiation field of view of the light sources; one or more electromagnetic radiation detectors coupled to the head-mounted member and configured to receive light reflected after encountering the target object; and a controller operatively coupled to the one or more light sources and detectors and configured to determine and display an output indicating the identity or property of the target object as determined by the light properties measured by the detectors in relation to the light properties emitted by the light sources.

Abstract: Aspects relate to a portable device that may be used to identify a critical intensity and an anaerobic work capacity of an individual. The device may utilize muscle oxygen sensor data, speed data, or power data. The device may utilize data from multiple exercise sessions, or may utilize data from a single exercise session. The device may additionally estimate a critical intensity from a previous race time input from a user.

Abstract: A storage unit stores a cumulative light emitting frequency or a cumulative light emitting time of a light emitting element. In a case where the cumulative light emitting frequency is greater than a predetermined light emitting frequency or the cumulative light emitting time is longer than a predetermined light emitting time, a control unit causes the light emitting element to emit light toward a living body by increasing the light emitting frequency or the light emitting time at which the light emitting element emits the light in order to acquire a light receiving result once, compared to a setting light emitting frequency or a setting light emitting time. A light receiving unit acquires information of the living body, based on a light receiving result obtained by receiving the light which is emitted toward the living body and transmitted through the living body.

Abstract: A living-body information measuring device includes a first light-emitting unit that emits a single-mode laser beam, a second light-emitting unit that emits a multi-mode light beam or an LED light beam, a light-receiving element that receives reflected or transmitted light beams reflected or transmitted by a living body when the first light-emitting unit and the second light-emitting unit emit the beams toward the living body, a control unit that controls light-emission periods of the first light-emitting unit and the second light-emitting unit, and a measurement unit that measures plural types of living-body information about the living body by using each of the reflected or transmitted light beams that are successively received by the light-receiving element.

Abstract: A method and system for measuring oxygen levels and various blood constituents utilizing a sensor having one or more light sources, and one or more light detectors is disclosed. The system is capable of using data collected by the one or more detectors from a non-monochromatic light source to provide accurate information during motion events occurring with an extremity the sensor. The system is also capable of detecting and providing an alert if the sensor is not properly placed on a patient or becomes disengaged therefrom.

Abstract: A non-invasive, optical-based physiological monitoring system is disclosed. One embodiment includes an emitter configured to emit light. A diffuser is configured to receive and spread the emitted light, and to emit the spread light at a tissue measurement site. The system further includes a concentrator configured to receive the spread light after it has been attenuated by or reflected from the tissue measurement site. The concentrator is also configured to collect and concentrate the received light and to emit the concentrated light to a detector. The detector is configured to detect the concentrated light and to transmit a signal representative of the detected light. A processor is configured to receive the transmitted signal and to determine a physiological parameter, such as, for example, arterial oxygen saturation, in the tissue measurement site.

Abstract: The invention provides a pulse oximetry sensor for attachment to the lower half of the palm or the ulnar edge of the palm. The sensor may be portable, untethered and in some instances, disposable. The features of the sensor make it effective in stable, chronic or emergency medical settings.

Abstract: Optical-electronic device configured to generate a calibration factor for use in determining optical density. The device includes at least one emitter configured to emit light, a detector configured to receive light and transmit data representative of the received light and a processor coupled to the at least one emitter and the detector. The device further includes a non-transitory storage medium coupled to the processor and configured to store instruction to cause the device to perform the calibration method. Additionally, a calibration container includes a main body, upper lid, and a lower lid. The main body is configured to receive the device and an object having known optical properties.

Abstract: An iron redox flow battery system, comprising a redox electrode, a plating electrolyte tank, a plating electrode, a redox electrolyte tank with additional acid additives that may be introduced into the electrolytes in response to electrolyte pH. The acid additives may act to suppress undesired chemical reactions that create losses within the battery and may be added in response to sensor indications of these reactions.

Abstract: A method and apparatus of compensating for a differential error between a plurality of body surface sensors, where each sensor respectively comprises a transmitter and a receiver.

Abstract: Provided is a living-body information measurement device including a first light emitting element and a second light emitting element each that emits different light in wavelength, a light receiving element that receives the light emitted from the first light emitting element and the second light emitting element, a control unit that controls an emission period of each of the first light emitting element and the second light emitting element so that the number of times of emission of the second light emitting element per unit time is less than the number of times of emission of the first light emitting element per unit time, and a measuring unit that measures plural living-body information based on the light received in the light receiving element.

Abstract: Devices and systems have a sensor probe configured to measure tissue oxygen saturation in the intestine or mesentery. The devices and systems can determine the oxygenation state of the entire thickness of the intestine or mesentery. Embodiments of the invention also include methods for inducing a temporary ischemic period in an intestine or mesentery tissue and analyzing changes in oxygen saturation of the tissue during the temporary ischemic period or during a recovery phase. The devices, systems, and methods can be applied in diagnosing intestinal ischemia in a patient, as well as in monitoring tissue oxygen saturation of the intestine or mesentery during or after a surgical procedure.

Abstract: Devices and systems have a sensor probe configured to measure tissue oxygen saturation in the intestine or mesentery. The devices and systems can determine the oxygenation state of the entire thickness of the intestine or mesentery. Embodiments of the invention also include methods for inducing a temporary ischemic period in an intestine or mesentery tissue and analyzing changes in oxygen saturation of the tissue during the temporary ischemic period or during a recovery phase. The devices, systems, and methods can be applied in diagnosing intestinal ischemia in a patient, as well as in monitoring tissue oxygen saturation of the intestine or mesentery during or after a surgical procedure.

Abstract: A method of assembling an opto-physiological (OP) sensor comprises: (i) modelling the opto-physiological properties of at least one body tissue type to be monitored; (ii) determining, through application of the model, an optimal optical design for an opto-physiological (OP) sensor operable to monitor the opto-physiological properties of the at least one body tissue type; and (iii) making the OP sensor to the determined optical design. The optimal optical design for the OP sensor comprises: (i) determining the optimum separation of each of a plurality of light sources from a photodetector, based on modelled optical path lengths for light travelling from each light source, through the body tissue type to be monitored, to the photodetector; and (ii) locating light sources of different wavelengths at different distances from the photodetector.

Abstract: A near infrared spectrophotometric sensor assembly for non-invasive monitoring of blood oxygenation levels in a subject's body is provided. The assembly includes at least one light source, at least one light detector operable to detect light emitted by the light source, an electromagnetic interference shielding disposed around at least a portion of the light detector, wherein the electromagnetic interference shielding includes an electrically conductive substrate that is optically transparent, and one or both of a light blocking sheet disposed relative to at least one of the light detectors and an encapsulating material.

Abstract: A biosensor including light emitting elements and a light receiving element disposed on a principal surface of a wiring board; a light shielding portion disposed between a light-emitting-element sealing portion and a light-receiving-element sealing portion; a base medium having light transmitting properties, disposed in parallel with the wiring board with the light shielding portion therebetween; an adhesion layer having light transmitting properties that bonds the base medium with the light-emitting-element sealing portion, the light-receiving-element sealing portion, and the light shielding portion; and a first electrocardiograph electrode attached to a principal surface of the base medium. Both end portions of the adhesion layer and both end portions of the base medium are disposed such that they overlap neither of the light-receiving-element sealing portion nor the light-emitting-element sealing portion when viewed from a direction normal to the principal surface of the wiring board.

Abstract: A stand-on physiological sensor (e.g. floormat) measures vital signs and various hemodynamic parameters, including blood pressure and ECG waveforms. The sensor is similar in configuration to a common bathroom scale and includes electrodes that take electrical measurements from a patient's feet to generate bioimpedance waveforms, which are analyzed digitally to extract various other parameters, as well as a cuff-type blood pressure system that takes physical blood pressure measurements at one of the patient's feet. Blood pressure can also be calculated/derived from the bioimpedance waveforms. Measured parameters are transmitted wirelessly to facilitate remote monitoring of the patient for heart failure, chronic heart failure, end-stage renal disease, cardiac arrhythmias, and other degenerative diseases.

Abstract: A method, system, or apparatus for determining a hydration condition of a user. The apparatus includes a housing. The apparatus further includes a light source disposed at an edge of the housing in a first position, wherein the light source, when affixed to a surface of a body, is operable to emit light into the body from the first position. The apparatus further includes an optical sensor disposed at the edge of the housing in a second position, the second position being a fixed distance from the first position to measure backscatter of the light reflected by a muscular-walled tube of the body at a depth below the surface of the body.

Abstract: A method for monitoring autoregulation includes receiving a blood pressure signal and an oxygen saturation signal, determining a phase difference between the blood pressure signal and the oxygen saturation signal, and determining a patient's autoregulation status based at least in part on a phase difference between the blood pressure signal and the oxygen saturation signal.

Abstract: A living-body information measuring device includes plural light-emitting elements, a light-receiving element that is disposed at a position at different distances from the light-emitting elements and that receives reflected light beams that are reflected from a living body when the light-emitting elements emit light beams toward the living body, a control unit that controls the light-emitting elements so that the light-emitting elements successively emit the light beams, and a measurement unit that measures living-body information at plural depths in the living body by using the reflected light beams that are successively received by the light-receiving element.

Abstract: A tissue oximetry system employing diffuse optical spectroscopy includes an optical subsystem and an electronics and processing subsystem, together generating modulated optical signals processing a response optical signal in order to obtain measurements of blood oxygen values for a tissue from per-wavelength absorption values. Signal sources generate RF modulation signals, and ADC circuitry generates streams of digital sample values from analog detection signals.

Abstract: Correction of a non-invasive blood glucose measurement measured from a video image. Correction includes irradiating white light on the skin, filtering the white light reflected from the skin by a first wavelength filter and a second wavelength filter, obtaining a first signal including a blood glucose signal and a pulse signal based on a video image generated by the white light filtered by the first wavelength filter, obtaining a second signal including a pulse signal based on a video image generated by the white light filtered by the second wavelength filter, obtaining a blood glucose signal by subtracting the second signal from the first signal, and calculating the amount of blood glucose in a subcutaneous blood vessel based on the obtained blood glucose signal. Moreover, fundamental blood glucose signals can be extracted in real time without collecting blood.

Abstract: An electronic device includes one or more light sources for emitting light toward a body part of a user and one or more optical sensors for capturing light samples while each light source is turned on and for capturing dark samples while the light source(s) are turned off. A signal produced by the one or more optical sensors is demodulated produce multiple demodulated signals. Each demodulated signal is received by one or more decimation stages to produce a signal associated with each light source. Each signal associated with the light source(s) is analyzed to estimate or determine a physiological parameter of the user.

Abstract: An optical sensor is provided. The optical sensor has an emitting system including at least one light emitting device which emits light onto an object; and a detecting system detecting the light which has been emitted by the emitting system and which has propagated through the object. The light emitting device is capable of emitting a plurality of light beams with different wavelengths onto substantially the same position of the object.

Abstract: Methods and devices to monitor an analyte in body fluid are provided. Embodiments include continuous or discrete acquisition of analyte related data from a transcutaneously positioned in vivo analyte sensor automatically or upon request from a user.

Abstract: There is provided a biosensor capable of improving the S/N ratio of a final photoplethysmographic signal regardless of the change in a noise component such as extraneous light. A biosensor includes a driving signal generation unit for generating a pulsed driving signal, a light-emitting element for emitting light in response to a generated driving signal, a light-receiving section including a light-receiving element for outputting a detection signal in accordance with the intensity of light received and an amplification unit for amplifying a detection signal output from the light-receiving element, a filter unit for removing a pulse wave component from a detection signal output from the light-receiving section to obtain a baseline signal, and a differential amplification unit for taking a difference between a detection signal output from the light-receiving section and a baseline signal obtained by the filter unit.

Abstract: Methods and apparatus are presented for removing motion artifacts from physiological signals produced by a physiological sensor of a wearable device, wherein the physiological sensor includes at least one optical emitter and at least one optical detector. Light emitted by the at least one optical emitter that is scattered by a body of a subject wearing the device is detected, and a physiological information signal therefrom is produced via the at least one optical detector. Light emitted by the at least one optical emitter that is scattered by a light regulating region of the wearable device is detected, and a motion noise information signal is produced via the at least one optical detector. The physiological information signal and the motion noise information signal are processed via at least one processor associated with the wearable device to at least partially remove unwanted motion artifacts from the physiological information signal.

Abstract: A system and method of dynamically localizing a measurement of parameter characterizing tissue sample with waves produced by spectrometric system at multiple wavelengths and detected at a fixed location of the detector of the system. The parameter is calculated based on impulse response of the sample, reference data representing characteristics of material components of the sample, and path lengths through the sample corresponding to different wavelengths. Dynamic localization is effectuated by considering different portions of a curve representing the determined parameter, and provides for the formation of a spatial map of distribution of the parameter across the sample. Additional measurement of impulse response at multiple detectors facilitates determination of change of the measured parameter across the sample as a function of time.

Abstract: An optical sensor including an irradiation system including at least one light irradiator, the at least one irradiator including a surface emitting laser array having a plurality of light-emitting units, and a lens disposed in an optical path of the plurality of rays of light emitted from the plurality of light-emitting units to cause light exit directions of at least two of the plurality of light-emitting units to be not parallel to each other, such that the at least one irradiator irradiates a same point of a test object with a plurality of rays of light that are not parallel to each other. The optical sensor also including a detection system configured to detect the plurality of rays of light that are emitted from the irradiation system and propagated inside the test object.

Abstract: A method for test strip recognition and interpretation is provided. The method includes the following steps. A plurality of test strips are provided, wherein the test strips are configured to examine a plurality of physiologic parameters respectively, and the test strips respectively have a plurality of color characteristics corresponding to the physiologic parameters respectively. A plurality of physiologic parameter examinations are performed to the corresponding test strips respectively, so as to obtain a plurality of test reactions. An image of the test strips is captured. The color characteristics and the test reactions of the test strips are obtained according to the image. The physiologic parameters examined by the test strips respectively are obtained according to the color characteristics. The physiologic parameters examined by the test strips are matched with the test reactions to obtain a plurality of physiologic parameter examination results.

Abstract: Systems, apparatuses and methods may provide for a transmit circuit including a light source and a receive circuit including a photodetector and a transimpedance amplifier (TIA) coupled to the photodetector. Additionally, a calibration circuit may be coupled to the transmit circuit and the receive circuit, wherein the calibration circuit includes a current controller to set an operational current of the light source to a minimum value that results in a target output voltage of the receive circuit. In one example, the gain of the TIA remains substantially constant during calibration of the receive circuit.

Abstract: A handheld infrared spectroscopy device and method of use. The device is a hand-held spectroscopy device, that may be integral to a mobile phone or smart device such as a smart phone, tablet, personal digital assistant, computer or other device that is portable and capable of performing applications. A liquid sample port internal to the device and in close proximity to the device spectrometer performs infrared spectra analysis on liquid samples, allowing both portability as well as highly sophisticated and specific spectral analysis of liquid samples. The device has wireless communication capability, enabling transmission of data and spectral imagery across the globe.

Abstract: A biological sensor capable of improving the signal-to-noise ratio of a detection signal obtained by a light-receiving element and amplified by an amplifier is provided. The biological sensor includes a driving signal generating unit that generates a pulse-form driving signal, a light-emitting element that emits light in response to the generated driving signal, a light-receiving element that outputs a detection signal based on an intensity of received light, an amplifying unit including first and second operational amplifiers that amplify the outputted detection signal, an offset signal generating unit and a voltage dividing resistor group that generate a pulse-form offset voltage for offsetting a reference potential of the first operational amplifier when amplifying the detection signal and apply the offset voltage to the first operational amplifier, and a computation unit that obtains biological information by processing the detection signal amplified by the amplifying unit.

Abstract: Provided are a photoplethysmographic measurement apparatus, a photoplethysmographic measurement method, and an apparatus for measuring a biosignal. The photoplethysmographic measurement apparatus includes a probe, a light emitter comprising a nonelectrical light source and disposed at one end of the probe, the light emitter configured to illuminate a measurement part, and a light receiver disposed at another end of the probe and configured to detect light reflected or transmitted by the illuminated measurement part.

Abstract: An apparatus and method for noninvasive measurement of a fluorescent analyte concentration in the blood of a patient by exciting the blood and the analyte at two wavelength ranges and measuring the emission spectrum of the fluorescent analyte when (i) the difference of emission intensities at the excitation wavelength ranges of the fluorescent analyte is greater than that of background fluorophores, and (ii) when blood absorbance at the two excitation wavelength ranges is similar. An apparatus and method for measurement of a fluorescent analyte concentration in the blood of a patient is provided.

Abstract: A system is disclosed for detecting and calculating the level of ambient and/or environmental noise, such as electromagnetic interference generated by electric power lines, ambient lights, light dimmers, television or computer displays, power supplies or transformers, and medical equipment. In some embodiments, the system performs frequency analysis on the interference signal detected by light photodetectors and determines the power of the interference signal concentrated in the analyzed frequency bands. The worst-case interference level can be determined by selecting the maximum from the computed power values. In some embodiments, the determined interference signal power can be compared with the noise tolerance of a patient monitoring system configured to reliably and noninvasively detect physiological parameters of a user. The results of the comparison can be presented to the user audio-visually. In some embodiments, the system can be used to perform spot check measurements of electromagnetic interference.

Abstract: A monitoring device configured to be attached to the ear of a person includes a base, an earbud housing extending outwardly from the base that is configured to be positioned within an ear of a subject, and a cover surrounding the earbud housing. The base includes a speaker, an optical emitter, and an optical detector. The cover includes light transmissive material that is in optical communication with the optical emitter and the optical detector and serves as a light guide to deliver light from the optical emitter into the ear canal of the subject wearing the device at one or more predetermined locations and to collect light external to the earbud housing and deliver the collected light to the optical detector.

Abstract: A noninvasive blood measurement platform may be used to determine the amounts of various constituents of the blood based on the bulk absorption characteristics of the blood. The platform may measure bulk absorption of energy such as, a broad-spectrum light, to determine maximum and minimum blood volumes. The platform may measure bulk absorption of energy at the maximum and minimum blood volumes. The bulk absorption measurements may be transformed using a transformation operation to determine bulk absorption characteristics in terms of frequency and/or wavelength. A time-varying component of the bulk absorption characteristics may be derived by comparing the bulk absorption characteristics at the maximum blood volume to the bulk absorption characteristics at the minimum blood volume. Multivariate analysis may be performed on the time-varying component to determine the amount of the one or more constituents of the blood.