Methods and devices for aligning miniaturized spectrometers and impedance sensors in wearable devices

A device, comprising:

• a band configured to extend at least partially around a body part of a user, the body part comprising a dermal layer and a subdermal feature within body part;
• a light source integrated into the band, wherein the light source is configured in the band to emit light into the body part through the dermal layer;
• a miniaturized spectrometer integrated into the band and positioned in the band at a distance along the band from the light source as defined by a curved non-linear light path between the light source and the miniaturized spectrometer, wherein the miniaturized spectrometer is configured to press against the bottom half of the wrist as the user wears the flexible band to receive the light through the dermal layer along the curved non-linear path;
• and
• an impedance sensor integrated into the band and configured to be positioned, as the user wears the band, against a same side of the body part as the miniaturized spectrometer, wherein the miniaturized spectrometer is configured in the band to be positioned along a same side of the body part as the impedance sensor as the user wears the band.

A method, comprising:

• placing a wearable device at least partially around a body part of a user, the wearable device configured to take simultaneous measurements of a feature of the body part with two different types of sensors, the wearable device comprising:
• a band shaped to extend at least partially around the body part of the user, the body part comprising a dermal layer, a subdermal structure within body part, a first side, and a second side facing a different direction than the first side;
• a light source integrated into the band, wherein the light source is configured in the band to emit light into the body part through the dermal layer;
• a miniaturized spectrometer integrated into the band and positioned in the band at a distance along the band from the light source as defined by a curved non-linear light path between the light source and the miniaturized spectrometer, wherein the miniaturized spectrometer is configured to press against the bottom half of the wrist as the user wears the flexible band to receive the light through the dermal layer along the curved non-linear path;
• an impedance sensor integrated into the band and positioned in the band to be situated along a same side of the body part as the miniaturized spectrometer as the user wears the band, the same side comprising either the first side of the body part or the second side of the body part;
• and
• a processing device configured to take simultaneous measurements with the miniaturized spectrometer and the impedance sensor, the processing device communicatively coupled to the impedance sensor and the optical sensor;
• emitting, by the light source, the light through the body part;
• detecting, by the optical sensor, the relevant constituent wavelength;
• measuring an impedance of the body part by the impedance sensor simultaneously with the light source emitting the light and the optical sensor detecting the relevant constituent wavelength;
• and
• communicating to the processing device an impedance measurement from the impedance sensor and an optical measurement from the optical sensor.