The development of holography promises a future in which we can enjoy a fully interactive 3D experience with our bare eyes. It removes the need to wear special 3D glasses to view realistic resemblances of three-dimensional objects. Yet this future still remains a distant fantasy that we only dream of. Currently established holographic methods are beset with physical limitations and restrictions that render this technology ill-suited for mainstream convenient use. The research team headed by Professor YongKeun Park from the Department of Physics may have developed a new technique that could bring us a step closer towards achieving this goal.
Every three-dimensional object scatters light in all directions, making it visible from any angle or perspective. However, most of the common holographic approaches generate images that can only be viewed clearly within a narrow range of angles. Furthermore, these images are generally small, especially for multi-user platforms. Previous attempts to address these deficiencies have either introduced more complicated systems or presented trade-offs on other existing features, both of which compromise the technology’s potential for wide-scale implementation.
Professor Park’s team made use of ultra-high capacity non-periodic photon sieves, which are essentially thin films with irregularly positioned pinholes of equal size that can diffract light at more random directions, thus widening the viewing angle. These sieves are combined with transmissive liquid crystal display (LCD) panels to further enhance the diffraction angle. With this technique, the team successfully optimized an effective viewing angle of 30° on an approximately 3 cm by 3 cm screen. This angle could be increased more when smaller-sized pinholes are used. It also observed a simultaneous projection of dynamic color holograms when the LCD panels were illuminated red, green, and blue at 60 Hz.
Even with such impressive results, the team acknowledges its method’s practical shortcomings, such as its low power efficiency and the slight, inevitable uniformity in pinhole positioning. Nevertheless, the research team looks forward to the possible applications of its study, specifically its integration into thin holographic displays and LCD production.