External 3-Dimensional Holodeck Scenery
In it's simplest form, invisibility is depicted outside of the Light-Interface System, while an intersection ( holodeck) of the outside light is displayed, painted all along the interior walls in the Light-Interface, itself.
External Holodeck Scenery
The external world is transmitted thru the Light-Interface System, and part is diverted into continuing it's path thru the space that the Light-Interface System rests in, while a seperate holodeck reality can be painted all along the interior walls of the Light-Interface.
Internal Hologram Casting
If not a computer-generated internal hologram, such as a person or other furniture of the background scenery, it must first be projected from another " input receiving" Light-Interface, before it can be flipped around and transmitted back out the telepresence Light-Interface where the holodecks of the subject and the object can interact together.
Dual-Holodeck Properties: External Holodeck Scenery/ Internal Hologram Casting
A holodeck requires both the outside 3-Dimensional wrap-around bounding scenery, as well as the internal matter of the scenery, the 3-Dimensional " floating" holograms casted within the outside 3-D bounding scenery.