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Herein, the design and implementation of a transparent 3D touch‐enabled surface for richer user interaction with midair 3D virtual objects in a touch‐interactive pseudo‐holographic display are presented. Frustrated total internal reflection (FTIR)‐based touch sensing is used in combination with a four‐sided pyramidal pseudo‐holographic projection. The developed system allows gesture‐based control and smooth touch interaction through facile and inexpensive hardware and open‐source software tools. A software application is also developed as the interface between the touch/gesture‐sensing system and the optical display. By bringing the virtual and real world closer through touch‐based interaction, the presented system will enrich user experience and enable advances in areas such as education, entertainment, gaming, retail, and museums where holograms are currently used.

The rainbow hologram provides views of reconstruction with rainbow color within a large viewing zone. In our recent paper, a Fourier rainbow holographic display using diffraction grating and a white‐light LED source was introduced. In this technique, the rainbow effect is realized by the dispersion of white‐light source on diffraction grating, while the slit is implemented numerically by reducing the demands of the space‐bandwidth product of the display. This paper presents a novel analysis on the visual perception of the Fourier rainbow holographic display using Wigner distribution. The view‐dependent appearance of the image, including multispectral field of view and viewing zone, is investigated considering the observer and the display parameters. The resolution of the holographic view is also investigated. For this, a new quantitative assessment for image blur is introduced using Wigner distribution analysis. The analysis is supported with numerical simulations and experimentally captured optical reconstructions for the holograms of the computer model and real object generated with different slit size, reconstruction distance, and different observation conditions.

Holography has been fascinating people for almost 70 years (since Gabor's invention in 1947) as a true three‐dimensional (3D) imaging technology that can replicate 3D scenes in free space. Holography has also led to important developments in physics and technology as manifested by fundamental ideas proposed by renowned scientists and holographers, such as Emmeth Lieth (off‐axis holography), Yuri Denisyuk (reflection holography), Stephen Benton (rainbow holography), and Adolf Lohmann (computer‐generated holograms). Their ideas have been established as essential concepts and have advanced considerably the field of optical and digital holography during the past fifty years. The 21st century is the age of digital technology and tremendous progress in optoelectronics and micro/nanotechnology has been accomplished. This progress has opened the doors for true holographic applications in important areas such as holographic 3D displays with photorealistic visualization, 3D quantitative imaging in biomedicine, optical metrology using digital holographic interferometry, microscopy, and tomography. Successful applications and true holographic products in the market have advanced holography to a level at which standards setting organizations must be involved to guarantee interoperability between devices and applications.

Metasurfaces provide a compact and powerful platform for manipulating the fundamental properties of light, and have shown unprecedented capabilities in both optical holographic display and information encryption. For increasing information display/storage capacity, metasurfaces with more polarization manipulation channel and full-color holographic functionality are now an urgent requirement. Here, a minimalist dielectric metasurface with the capability of full-color holography encoded with arbitrary polarization is proposed and experimentally demonstrated. Without the daunting exploratory and computational problem in nanostructure searching, full-color holographic images can be multiplexed into arbitrary polarization channels through vectorial ptychography and k-space ptychography based on tetratomic macropixel geometric phase metasurfaces. Thanks to the full degree of freedom tuning in polarization and color spaces, the application scenarios such as holographic 3D imaging and information encryption are realized. The strategy exhibits promising potential in applications of 3Dl display, augmented/virtual reality, high-density data storage, and encryption.

The viewing-zone scanning holographic display, which can enlarge both screen size and viewing zone, is modified to enable color image generation by using the time-multiplexing technique; R, G, and B lasers sequentially illuminate a single microelectromechanical systems spatial light modulator with a high frame rate. The viewing-zone scanning system enlarges screen size by using a magnifying imaging system and generates a large number of reduced viewing zones that are aligned in the horizontal direction by a horizontal scanner to enlarge the viewing zone. The interval of the reduced viewing zones is set to be one-third of the width of the reduced viewing zones or less so that three sets of reduced viewing zones are generated corresponding to the three colors. Color image generation was demonstrated for a screen size of 2.0 in. and a viewing zone angle of 40.0°.

Holography is considered to be the next generation of technology to achieve true three-dimensional (3D) displays as it can reconstruct the wavefronts of light with the whole depth cues of a real 3D scene. Current updatable holographic materials lack multiplexing properties and fatigue resistance for 3D displays. We report on a new holographic material of side-chain diarylethene polymer with the thickness of 320 μm, minimum multiplexing angle of 0.17°, rapid response time of several seconds, and fatigue resistance. The updatable reconstructions of 3D scenes with write/erase cycles are realized in experiments. This thick photochromic polymer shows potential for applications such as real-time 3D displays for big data. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016, 54, 2050–2058

In this paper, we propose a method of holographic magnification based on Fresnel diffraction. Similarity principle of Fourier transform is used in convolution algorithm in order to adjust the size of the reconstructed image. With the splicing technology based on a spatial light modulator, the reconstructed images can be magnified. By combining the similarity principle of Fourier transform with the splicing technology, the reconstructed images can be further magnified to eight times, which is verified by the experiments.

Novel 3D display architecture and algorithm are proposed and demonstrated Full HD 3D image with reduced accommodation-vergence conflict using limited computing power and a conventional LCD panel. The proposed 3D display architecture is integrated with a commercial 5.5” Full HD LCD panel and the used algorithm needs remarkably lower computing power than a conventional CGH algorithm based on Fresnel transformation. The experimental results show the accommodation depth cue which provides a clear 3D image only on focus position.

Ever since Emmett Leith and Juris Upatnieks were able to show the world's first true hologram of a steam locomotive people have imagined being able to generate dynamic holographic displays. While fully dynamic 3D holographic displays still present significant challenges, Daqri Holographics has developed a revolutionary phase only holographic display technology that is a compelling solution for many applications. Developing a dynamic holographic display presents a significant challenge, however its application to automotive products with their exacting quality requirements introduces additional and significant challenges. These have been overcome and a head up display based on this technology is now in production. This paper will look at the principles and benefits of utilising phase holographic displays in head up display applications and will discuss some of the challenges that had to be overcome.

The Field of View (FOV) properties and effects of the reflection Volume Holographic Grating (VHG) in conical mounting was studied when used in a see through Head Mounted Display in detail. Also, two methods for enlarging the FOV and improving the color uniformity for reflection VHG were analyzed and simulated.

We achieved individual-pixel phase modulation of 1 pm-pitch liquid crystal on silicon (LCOS) using dielectric shield walls for wide-viewing-angle holographic displays. The simulation results clarified the dielectric walls could suppress the alignment disorder by the effect of elastic force of liquid crystal (LC) and fringe electric field to adjacent pixels. The LC alignment on the walls was also discussed experimentally.

The current state-of-the-art of photorefractive and photoactive polymers for holographic applications is summarized and reviewed. Photorefractive polymers and some kinds of photoactive materials based on the azobenzene chromophore have great potential for updatable holographic applications. Updatable three-dimensional holographic displays of large size have been developed using photorefractive polymers as well as photoactive azobenzene materials. Time responses of photorefractive polymers of the order of seconds and hundreds of milliseconds are currently improved to be of the order of milliseconds to hundreds of microseconds with high diffraction efficiency and high optical gain. © 2016 Society of Chemical Industry

Coherent backlight is an important component in holographic 3D displays. In this paper, a novel coherent backlight featuring a compact design is presented. The feasibility of this structure is experimentally verified by reconstructing 3D images with a spatial light modulator. The diffraction efficiency of the system is ~4.3%.

We demonstrate a binocular holographic display with an amplitude-only spatial light modulator (SLM), which enables us to display a 3D scene with much higher frame rate than the case of a conventional stereoscopic 3D. Instead of dividing either frames or pixels for assigning the left and right images, we divide the space near pupils by modulating the phase of a computer generated hologram.