Head-mounted light field display with integral imaging and relay optics

A head-mounted display integral imaging (InI) system, comprising:

• a microscopic InI unit (micro-InI) configured to create light fields of a selected 3D scene at a selected position along an optical axis of the system;
• a relay group having a vari-focal element (VFE) disposed therein, the relay group disposed on the optical axis at a location so the selected position is an optical conjugate of the relay group, the relay group configured to receive the light fields created by the microscopic InI unit and to create an intermediate 3D scene on the optical axis of the selected 3D scene, the relay group configured to tune the position along the optical axis of the intermediate 3D scene;
• and
• eyepiece optics for imaging the intermediate 3D scene from the relay group into an exit pupil of the system for viewing by a user of the head-mounted display system.