J. Eur. Opt. Society-Rapid Publ. 22, 22( 2026) 223
Figure 11.( a) A long-exposure image shows 12 drones transitioning from a helix to a spiral motion in sync with a musical beat.( b) A close-up view of one of the drones during the performance [ 50 ].
compact lattice and grating structure. The microlens array gives rise to a“ negative refraction” phenomenon, which causes diverging light rays to converge symmetrically onto a flat plane. This process produces a life-sized 3D image and enables medium-free aerial display.
3.4.3 Floating 3D display of microchannel matrix optical waveguide
Floating 3D display, as the term suggestes, is a method for generating 3D images without the need for a physical medium. At the core of this technology lies the micro-channel matrix optical waveguide plate( MOW-plate), a nanoscale display material derived from advances in nano-optics. This material reconstructs the light field through an optical micro-mirror structure, producing a real image that can be interactively displayed in mid-air, as shown in Figure 12 [ 52, 53 ]. The integration of interactive algorithms with user experience design forms the foundation of medium-free 3D display technology, as depicted in Figure 13.
The MOW-plate is crucial to the realization of this technology. Its optical micro-mirror structure can capture the intensity, angle, wavelength, and other properties from each light beam of the physical light source onto the light plate in the“ object space”. It then reproduces this light, faithfully
Figure 12. The display principle of medium-free 3D technology relies on a microchannel matrix optical waveguide plate and negative-index materials.
mirroring it into the“ image space” on the opposite side of the array. These replicated rays are then refocused to form a real image at the symmetrical position between the“ object space” and the“ image space”. This image is a complete mirror of the original, medium-free, and visible to the naked eye.