Abstract: A device for measuring blood pressure can include a housing including a groove to receive a finger of a user. The groove can have a curved end towards a center of the housing and can have a first dimension between 20 mm and 70 mm, a second dimension between 20 mm and 35 mm, and a third dimension between 3 mm and 10 mm. The device can include a light source disposed within the housing and positioned at a bottom region of the groove and configured to emit light in the groove. The device can include a photodetector disposed within the housing and positioned at the bottom region of the groove and configured to capture a sequence of image frames while the light is emitted. The device can include a processor configured to generate a photoplethysmographic (PPG) signal of a user using the sequence of image frames.

Abstract: Systems and methods for blood pressure estimation using smart offset calibration can include a computing device associating a calibration photoplethysmographic (PPG) signal generated from a first sequence of image frames obtained from a photodetector of the computing device with one or more measurement values generated by a blood pressure measurement device different from the computing device. The computing device can obtain a recording PPG signal generated from a second sequence of image frames obtained from the photodetector, and identify a calibration model from a plurality of blood pressure calibration models based on the calibration PPG signal and the recording PPG signal. The computing device can generate a calibrated blood pressure value using the recording PPG signal, features associated with the calibration PPG signal and the identified calibration model.

Abstract: Systems and methods for detecting data acquisition conditions using color-based penalties can include a computing device obtaining a sequence of images acquired by a photodetector. The computing device can determine, for each pixel position of a plurality of pixel positions associated with the sequence of images, a respective penalty score indicative of a similarity between a color value of a pixel of the pixel position and a desired color value. The desired color value can represent a color property of light emitted from body parts of users when placed opposite to the photodetector. The computing device can determine, using penalty scores of the plurality of pixel positions, a relative position of a body part of a user with respect to a desired position.

Abstract: Systems and methods for acquiring photoplethysmographic (PPG) signals for measuring blood pressure can include a computing device acquiring a sequence of images representing transdermal optical data of a subject, and generating a corresponding sequence of downsampled color frames. The computing device can identify, in each downsampled color frame, a respective central image block representing a central image region of the downsampled color frame and having a first size smaller than a second size of the downsampled color frame. The computing device can generate, for each downsampled color frame, a corresponding color intensity value based on the respective central image block. The computing device can generate, using color intensity values corresponding to the sequence of downsampled color frames, a PPG signal to determine a blood pressure value of the subject.

Abstract: Systems and methods for assessing PPG signals generated based on transdermal optical data can include a computing device generating a color intensity signal using an acquired sequence of transdermal images of a subject. The computing device can compute a signal quality metric of the color intensity signal. The computing device can provide an indication of a quality of the color intensity signal for display on a display device associated with the computing device. The indication of the quality of the color intensity signal can be determined based on the signal quality metric.