A volumetric display system including a volumetric display for displaying a scene viewable as a three-dimensional floating-in-the-air scene in a display space, enabling a user to reach a first object into the display space, a location determination unit locating real objects in the display space, providing a location of the first object when the first object is inserted into the display space, and a computer for receiving the location of the first object, detecting when the location of the first object is at a location where an object is displayed in the three-dimensional scene, thereby determining that the first object is viewable as touching the displayed object following a detection of the first object viewable as touching the displayed object, producing a new three-dimensional scene displaying the displayed object as if manipulated by the first object. Related apparatus and methods are also described.

A method for light detection and ranging that includes forming a first light pattern within a region of a scene by holographic projection. The first light pattern includes n light spots arranged in a regular array. A light return signal is received from each light detection element of an array of light detection elements directed at the region of the scene. The intensity of the light return signals is assessed. If the light return signals do not meet at least one signal validation criterion, a second light pattern is formed within the region of the scene by holographic projection. The second light pattern includes m light spots arranged in a regular array, wherein mn. A time-of-flight in association with each light spot of the second light pattern is then determined.

A three-dimensional holographic display device includes a light emitting diode (LED) array including a plurality of light sources controlled to sequentially output light according to a preset pattern, a lens configured to refract light incident from the LED array, a spatial light modulator (SLM) configured to modulate light incident from the lens, and a processor configured to generate a plurality of holographic signals each comprising depth information adjusted according to an arrangement location of each of the plurality of light sources, and for each of the plurality of light sources, control the SLM to modulate the light based on a holographic signal corresponding to the light source.