Wearable light-guiding bands for physiological monitoring
A monitoring device includes a band capable of encircling a portion of the body of a subject, and an optical emitter and detector attached to the band. The band includes comprises light transmissive material in optical communication with the optical emitter and optical detector and is configured to deliver light from the optical emitter to one or more locations of the body of the subject and to collect light from one or more locations of the body of the subject and deliver the collected light to the optical detector. The monitoring device may include a signal processor configured to receive and process signals produced by the optical detector, a transmitter configured to transmit signals processed by the signal processor to a remote device, and/or an optical filter.
1. A monitoring device, comprising:
a band configured to at least partially encircle a portion of the body of a subject, the band comprising:
a generally cylindrical outer body portion and a generally cylindrical inner body portion secured together in concentric relationship, the inner body portion comprising light transmissive material, and having outer inner surface;
a layer of cladding material near the inner body portion inner surface; and
at least one window formed in the cladding material that serves as a light-guiding interface to the body of the subject; and
at least one optical emitter and at least one optical detector attached to the band;
wherein the light transmissive material is in optical communication with the at least one optical emitter and the at least one optical detector and is configured to deliver light from the at least one optical emitter to one or more locations of the body of the subject via the at least one window and to collect light from one or more locations of the body of the subject via the at least one window and deliver the collected light to the at least one optical detector.
2. The monitoring device of claim 1 , wherein the portion of the body comprises a limb, a nose, an earlobe, and/or a digit.
3. The monitoring device of claim 1 , wherein the band comprises a lens region in optical communication with the at least one optical emitter that focuses light emitted by the at least one optical emitter.
4. The monitoring device of claim 1 , further comprising a light reflective material on at least a portion of one or both of the inner and outer surfaces.
5. The monitoring device of claim 4 , wherein the at least one optical detector comprises first and second optical detectors, and further comprising a signal processor, and wherein at least a portion of light reflected by the light reflective material and detected by the second optical detector is processed by the signal processor as a noise reference for attenuating motion noise from signals produced by the first optical detector.
6. The monitoring device of claim 1 , further comprising a signal processor configured to receive and process signals produced by the at least one optical detector.
7. The monitoring device of claim 1 , further comprising a transmitter configured to transmit signals processed by the signal processor to a remote device.
8. The monitoring device of claim 1 , wherein the at least one window comprises at least two windows, and further comprising light blocking material positioned between the at least one optical emitter and the at least one optical detector such that the at least one optical emitter and the at least one optical detector are not in direct optical communication with each other.
9. The monitoring device of claim 1 , wherein the band further comprises at least one optical filter configured to selectively pass at least one optical wavelength.
10. The monitoring device of claim 1 , wherein the band further comprises at least one optical filter configured to selectively pass at least one optical wavelength for transmission into the body of the subject.
11. The monitoring device of claim 10 , wherein the at least one optical detector comprises first and second optical detectors, and further comprising a signal processor, and wherein at least a portion of light blocked by the optical filter and detected by the optical detector is processed by the signal processor as a noise reference for attenuating motion noise from signals produced by the optical detector.