| abstract |
Techniques for respiratory and metabolic monitoring in mobile devices, wearable computing, security, illumination, photography, and other applications may use a phosphor-coated broadband white LED to produce broadband light, which may be transmitted along with ambient light to a target (e.g., ear, face, wrist, or the like). Some scattered light returning from a target may be passed through a spectral filter to produce multiple detector regions sensitive to a different waveband and/or wavelength range, and the detected light may be analyzed to determine a measure of a respiratory rate or effort. In the absence of LED light, ambient light may be sufficient illumination for analysis. The disclosed techniques may provide identifying features of type or status of a tissue target (e.g., respiratory rate, heart rate, heart rate variability, heart function, lung function, fat content, hydration status, confirmation of living tissue, and the like). |