Patent attributes
Systems are provided for detecting the flow of blood in vasculature by illuminating the blood with a source of coherent illumination and detecting one or more time-varying properties of a light speckle pattern that results from the scattering of the coherent illumination by tissue and blood. The movement of blood cells and other light-scattering elements in the blood causes transient, short-duration changes in the speckle pattern. High-frequency sampling or other high-bandwidth processing of a detected intensity at one or more points in the speckle pattern could be used to determine the flow of blood in the vasculature. Such flow-measuring systems are also presented as wearable devices that can be operated to detect the flow in vasculature of a wearer. Systems and methods provided herein can additionally be applied to measure flow in other scattering fluid media, for example in a scattering industrial, medical, pharmaceutical, or environmental fluid.