Wearable device and operation method therefor

A wearable device comprising:

• a substrate;
• a light emitter disposed on the substrate;
• a light receiver disposed on the substrate and spaced at a predetermined distance apart from the light emitter;
• a structure disposed on the substrate;
• an optical window disposed on the structure and configured to protect the light emitter and the light receiver;
• a first reflector disposed on the substrate adjacent to the light emitter;
• a second reflector disposed at a location facing a light emitting surface of the light emitter and disposed at a lower surface of the optical window;
• and
• a controller disposed on the substrate and configured to change reflection angles of the first and second reflectors,
• wherein the first reflector is in direct contact with the lower surface of the optical window;
• wherein the second reflector is in direct contact with a top surface of the substrate;
• wherein the first reflector is disposed on a light reflection path of the second reflector and reflects light reflected via the second reflector to a measurement object,
• wherein the light emitter generates light propagating in a first direction perpendicular to the measurement object, and
• wherein the first reflector reflects the light propagating in the first direction to a second direction in parallel to the measurement object, and the second reflector reflects the light reflected in the second direction to a third direction corresponding to the measurement object,
• wherein the controller is configured to classify combinations according to reflection angles of the first and second reflectors and determine reflection angles of the first and second reflectors within the classified combinations, and
• wherein the controller is configured to determine reflection angles of the first and second reflectors such that an optical path of light passing through the measurement object within the classified combinations is minimized,
• wherein the controller is configured to enter an angle setting mode of the first and second reflectors at time of initial wearing and time of re-wearing of the wearable device,
• wherein the controller is configured to detect a signal-to-noise ratio of an optical signal received via the light receiver in a state of entering the angle setting mode;
• and
• wherein the controller is configured to change the respective reflection angles of the first and the second reflectors to detect the signal-to-noise ratio of an optical signal received via the light receiver according to a combination of each of reflection angles, and set the respective reflection angles of the first and second reflectors based on a reflection angle corresponding to a greatest detected signal-to-noise ratio of the detected signal-to-noise ratios.