US Patent 11185290 Physiological monitoring devices and methods using optical sensors

A monitoring device configured to be attached to a subject includes a sensor configured to detect and/or measure physiological information and a processor coupled to the sensor. The sensor includes at least one optical emitter and at least one optical detector. The processor receives and analyzes signals produced by the sensor, and the processor changes wavelength of light emitted by the at least one optical emitter in response to detecting a change in subject activity. For example, the processor instructs the at least one optical emitter to emit shorter wavelength light in response to detecting an increase in subject activity, and the processor instructs the at least one optical emitter to emit longer wavelength light in response to detecting an decrease in subject activity. Detecting a change in subject activity may include detecting a change in at least one subject vital sign and/or subject motion.