One patent illustration and description suggests a method to make Glass into two distinct pieces that fit together. A piece would house the battery and internals while another band would be used for corrective lenses. A screw would bolt the two pieces together while also connecting the prism display to Glass. It’s possible the display could be attached on either the right or left to compensate for the wearer’s dominant eye.
via Google Glass patents hint at several design options including a flip-up display — Tech News and Analysis.