Wearable Electronic Device Having a Light Field Camera Usable to Perform Bioauthentication from a Dorsal Side of a Forearm Near a Wrist

A watch body, comprising:

• a housing;
• a cover mounted to the housing, the cover having:
• a first surface exterior to the watch body;
• and
• a second surface interior to the watch body;
• a light emitter positioned to emit light through the cover into a dorsal side of a forearm near a wrist of a user when the first surface of the cover is positioned adjacent the dorsal side of the forearm near the wrist;
• a light field camera positioned adjacent the second surface to receive remissions of the light through the cover from the dorsal side of the forearm near the wrist;
• and
• a tilt sensor configured to detect a tilt of the light field camera with respect to the dorsal side of the forearm near the wrist.

A method of authenticating a user of a wearable electronic device, comprising:

• emitting light into a dorsal side of a forearm near a wrist of the user;
• receiving, using a light field camera, remissions of the light from the dorsal side of the forearm near the wrist of the user;
• generating a light field image from the remissions of the light;
• performing a synthetic focusing operation on the light field image to construct at least one image of at least one layer of the forearm near the wrist;
• extracting a set of features from the at least one image;
• determining whether the set of features matches a reference set of features;
• and
• authenticating the user in response to the set of features matching the reference set of features.