Projection technique delivers 3D floating images

Concept of the approach and examples of application
Concept of the approach and examples of application

Japan’s National Institute of Communications Technology (NICT) has revealed a method to produce a floating, 3D image on a transparent display. Dubbed a ‘holographic 3D image’, the approach is tipped for use in HMDs, smart glasses and digital signage.

The projection-type see-through holographic 3D display technology combines an optical screen of a digitally designed holographic optical element (DDHOE) and a digital holographic projection technique. 

NICT demonstrated holographic 3D image reconstruction via the see-through screen to a target observation area.

The approach is said to avoid problems that prior technologies faced with screen size and viewing angles.

In a statement on its website, NICT said: “Basically, dynamic holographic 3D display technology faces the severe limitation of the spatial-temporal resolution of the spatial light modulator (SLM) to realize a practical display size and visual angle. Moreover, the general system design of holographic 3D displays requires a large optical setup behind the display window.”

The new approach projects a holographic 3D image on to a see-through screen of DDHOE using NICT’s digital holographic projection technique. The screen was fabricated using a hologram printer, which was developed by NICT. The light of the enlarged holographic 3D image was then concentrated to a target observation area, by a reflection function, to increase the visual angle. 

Part of the work was detailed in the journal Nature Communications on October 3, 2016 and you can read more details on the NICT website.