Instead of rendering a 3D scene on a flat surface, the display itself is three-dimensional, a property known as volumetric. This allows viewers to see a 3D image in the columnar display from all angles without any 3D glasses or headsets.
In The Optical Society’s journal for high impact research, Optica, researchers led by Yoshio Hayasaki of Utsunomiya University, Japan, demonstrated the ability of their volumetric bubble display to create changeable color graphics.
“Creating a full-color updatable volumetric display is challenging because many three-dimensional pixels, or voxels, with different colors have to be formed to make volumetric graphics,” said Kota Kumagai, first author of the paper. “In our display, the microbubble voxels are three-dimensionally generated in a liquid using focused femtosecond laser pulses. The bubble graphics can be colored by changing the color of the illumination light.”
To develop a volumetric display of the kind we see in science fiction movies is a dream of many display researchers, including us. Here, we show a new volumetric display with microbubble voxels. The microbubbles are three-dimensionally generated in liquid by focused femtosecond laser pulses. The use of a high-viscosity liquid, which is a key part of the development of this idea, slows down the movement of the microbubbles, and, as a result, volumetric graphics can be displayed.
Using a self-focused femtosecond laser and high frequency ultrasound (7.44MHz
This volumetric bubble display has a wide-angle view, simple refreshing, and no addressing wires, since the transparent liquid is accessed optically rather than electronically. It achieves full-color graphics composed of light-scattering voxels controlled by illumination light sources. Furthermore, a holographic laser drawing method based on a computer-generated hologram displayed on a liquid-crystal spatial light modulator controls the light intensity of the microbubble voxels with an increase in the number of voxels per unit time and the spatial shaping of the voxels.