Holographic image display system

A method of providing a user interface for a volumetric display, where the volumetric display is configured to display, to a viewer, a three-dimensional image representing a virtual three-dimensional object, and the user interface allows interaction with said virtual three-dimensional object using a real object, comprising:

• providing data for displaying a first three-dimensional image to a volumetric display, said data including data for generating an image of said virtual three-dimensional object by driving pixels of the three-dimensional display;
• wherein the volumetric display is one or more of:
• focal-length controlled display or hologramic display;
• using the volumetric display for displaying the data as said first three-dimensional image viewable as a three-dimensional floating-in-the-air scene in a display space;
• determining a location of at least one point of interest in said virtual three-dimensional object;
• detecting a location of a real object in the display space;
• detecting when the location of the real object in the display space is at the location of the at least one point of interest in said virtual three-dimensional object being displayed in the three-dimensional floating-in-the-air scene, thereby determining that the real object is viewable as touching the virtual three-dimensional object;
• and
• following a detection of the real object viewable as touching the virtual three-dimensional object:
• adjusting a geometry of said virtual three-dimensional object according to the location of the real object determined to be at the location of the at least one point of interest;
• producing data for displaying a second three-dimensional image to the three-dimensional display, said data for displaying a second three-dimensional image reflecting the adjustment of the geometry of the virtual three-dimensional object;
• displaying the second three-dimensional image such that the virtual three-dimensional object appears as if manipulated by the real object, said the second three-dimensional image replacing said first three-dimensional image,
• wherein the displaying the first three-dimensional image and the second three-dimensional image comprises
• displaying the first three-dimensional image and displaying the second three-dimensional image to appear to occupy a three-dimensional space in said display space;
• and
• displaying the first three-dimensional image or the second three-dimensional image in a manner which provides eye focus depth cues for said viewer in the first three-dimensional image and the second three-dimensional image, by driving pixels of the three-dimensional display.