Systems and apparatus for object detection using optical sensing

A wearable device comprising:

• a housing;
• a cover material;
• a crown at least partially external to the housing;
• an optical proximity sensor disposed under the cover material and configured with a field of view including the crown at least partially external to the housing or an area above the crown, the optical proximity sensor comprising a first light emitter, a second light emitter, and one or more light detectors;
• and
• a processor coupled to the optical proximity sensor;
• wherein the one or more light detectors comprises a first light detector aligned with the first light emitter and the second light emitter in a first direction, the first light detector configured to receive a first amount of light from the first light emitter and configured to receive a second amount of light from the second light emitter;
• wherein the processor is configured to:
• estimate a presence of an object touching or within a threshold distance from the crown;
• or
• estimate a distance between the object touching or within the threshold distance from the crown;
• and
• wherein the processor is further configured to determine a distance of an object to the optical proximity sensor or to the crown in a second direction, different than the first direction, based on the first amount of light and the second amount of light.