Apparatuses, methods and systems for multiple focal distance display

A method of backlighting displays of a head mounted virtual or augmented reality display system providing a three dimensional (3D) volumetric field of view (FOV) for a user of the display system;

• the display system including a display, a backlight configured to illuminate a back of the display, and an optical system positioned relative to the display configured to reflect light projected from a front of the display to an eye of a user wearing the display system, the method comprising:
• providing an image for presentation by the display system;
• determining a focal distance corresponding to the image from a plurality of focal distances in the 3D volumetric FOV;
• presenting the image on the display;
• illuminating the back of the display presenting the image with light having a first physical property corresponding to the determined focal distance selected from a plurality of physical properties of light generated by the backlight;
• wherein the light having the first physical property corresponds to one of a plurality of optical surfaces of the optical system, the one optical surface having a reflective coating that only reflects light having the first physical property, and wherein the light reflected by the one optical surface is perceived by the eye of the user as being located at the determined focal distance within the 3D volumetric FOV.