HOLOGRAPHICS: Combining Holograms with Interactive Computer Graphics

Among all imaging techniques that have been invented throughout the last decades, computer graphics is one of the most successful tools today. Many areas in science, entertainment, education, and engineering would be unimaginable without the aid of 2D or 3D computer graphics. The reason for this success story might be its interactivity, which is an important property that is still not provided efficiently by competing technologies – such as holography. While optical holography and digital holography are limited to presenting a non-interactive content, electroholography or computer generated holograms (CGH) facilitate the computer-based generation and display of holograms at interactive rates [2,3,29,30]. Holographic fringes can be computed by either rendering multiple perspective images, then combining them into a stereogram [4], or simulating the optical interference and calculating the interference pattern [5]. Once computed, such a system dynamically visualizes the fringes with a holographic display. Since creating an electrohologram requires processing, transmitting, and storing a massive amount of data, today’s computer technology still sets the limits for electroholography. To overcome some of these performance issues, advanced reduction and compression methods have been developed that create truly interactive electroholograms. Unfortunately, most of these holograms are relatively small, low resolution, and cover only a small color spectrum. However, recent advances in consumer graphics hardware may reveal potential acceleration possibilities that can overcome these limitations [6]. In parallel to the development of computer graphics and despite their non-interactivity, optical and digital holography have created new fields, including interferometry, copy protection, data storage, holographic optical elements, and display holograms. Especially display holography has conquered several application domains. Museum exhibits often use optical holograms because they can present 3D objects with almost no loss in visual quality. In contrast to most stereoscopic or autostereoscopic graphics displays, holographic images can provide all depth cues—perspective, binocular disparity, motion parallax, convergence, and accommodation—and theoretically can be viewed simultaneously from an unlimited number of positions. Displaying artifacts virtually removes the need to build physical replicas of the original objects. In addition, optical holograms can be used to make engineering, medical, dental, archaeological, and other recordings—for teaching, training, experimentation and documentation. Archaeologists, for example, use optical holograms to archive and investigate ancient artifacts [7,8]. Scientists can use hologram copies to perform their research without having access to the original artifacts or settling for inaccurate replicas. Optical holograms can store a massive amount of information on a thin holographic emulsion. This technology can record and reconstruct a 3D scene with almost no loss in quality. Natural color holographic silver halide emulsion with grain sizes of 8nm is today’s state-of-the-art [14]. Today, computer graphics and raster displays offer a megapixel resolution and the interactive rendering of megabytes of data. Optical holograms, however, provide a terapixel resolution and are able to present an information content in the range of terabytes in real-time. Both are dimensions that will not be reached by computer graphics and conventional displays within the next years – even if Moore’s law proves to hold in future. Obviously, one has to make a decision between interactivity and quality when choosing a display technology for a particular application. While some applications require high visual realism and real-time presentation (that cannot be provided by computer graphics), others depend on user interaction (which is not possible with optical and digital holograms). Consequently, holography and computer graphics are being used as tools to solve individual research, engineering, and presentation problems within several domains. Up until today, however, these tools have been applied separately. The intention of the project which is summarized in this chapter is to combine both technologies to create a powerful tool for science, industry and education. This has been referred to as HoloGraphics. Several possibilities have been investigated that allow merging computer generated graphics and holograms [1]. The goal is to combine the advantages of conventional holograms (i.e. extremely high visual quality and realism, support for all depth queues and for multiple observers at no computational cost, space efficiency, etc.) with the advantages of today’s computer graphics capabilities (i.e. interactivity, real-time rendering, simulation and animation, stereoscopic and autostereoscopic presentation, etc.). The results of these investigations are presented in this chapter

HOLOGRAPHICS: Combining Holograms with Interactive Computer Graphics

Among all imaging techniques that have been invented throughout the last decades, computer graphics is one of the most successful tools today. Many areas in science, entertainment, education, and engineering would be unimaginable without the aid of 2D or 3D computer graphics. The reason for this success story might be its interactivity, which is an important property that is still not provided efficiently by competing technologies – such as holography. While optical holography and digital holography are limited to presenting a non-interactive content, electroholography or computer generated holograms (CGH) facilitate the computer-based generation and display of holograms at interactive rates [2,3,29,30]. Holographic fringes can be computed by either rendering multiple perspective images, then combining them into a stereogram [4], or simulating the optical interference and calculating the interference pattern [5]. Once computed, such a system dynamically visualizes the fringes with a holographic display. Since creating an electrohologram requires processing, transmitting, and storing a massive amount of data, today’s computer technology still sets the limits for electroholography. To overcome some of these performance issues, advanced reduction and compression methods have been developed that create truly interactive electroholograms. Unfortunately, most of these holograms are relatively small, low resolution, and cover only a small color spectrum. However, recent advances in consumer graphics hardware may reveal potential acceleration possibilities that can overcome these limitations [6]. In parallel to the development of computer graphics and despite their non-interactivity, optical and digital holography have created new fields, including interferometry, copy protection, data storage, holographic optical elements, and display holograms. Especially display holography has conquered several application domains. Museum exhibits often use optical holograms because they can present 3D objects with almost no loss in visual quality. In contrast to most stereoscopic or autostereoscopic graphics displays, holographic images can provide all depth cues—perspective, binocular disparity, motion parallax, convergence, and accommodation—and theoretically can be viewed simultaneously from an unlimited number of positions. Displaying artifacts virtually removes the need to build physical replicas of the original objects. In addition, optical holograms can be used to make engineering, medical, dental, archaeological, and other recordings—for teaching, training, experimentation and documentation. Archaeologists, for example, use optical holograms to archive and investigate ancient artifacts [7,8]. Scientists can use hologram copies to perform their research without having access to the original artifacts or settling for inaccurate replicas. Optical holograms can store a massive amount of information on a thin holographic emulsion. This technology can record and reconstruct a 3D scene with almost no loss in quality. Natural color holographic silver halide emulsion with grain sizes of 8nm is today’s state-of-the-art [14]. Today, computer graphics and raster displays offer a megapixel resolution and the interactive rendering of megabytes of data. Optical holograms, however, provide a terapixel resolution and are able to present an information content in the range of terabytes in real-time. Both are dimensions that will not be reached by computer graphics and conventional displays within the next years – even if Moore’s law proves to hold in future. Obviously, one has to make a decision between interactivity and quality when choosing a display technology for a particular application. While some applications require high visual realism and real-time presentation (that cannot be provided by computer graphics), others depend on user interaction (which is not possible with optical and digital holograms). Consequently, holography and computer graphics are being used as tools to solve individual research, engineering, and presentation problems within several domains. Up until today, however, these tools have been applied separately. The intention of the project which is summarized in this chapter is to combine both technologies to create a powerful tool for science, industry and education. This has been referred to as HoloGraphics. Several possibilities have been investigated that allow merging computer generated graphics and holograms [1]. The goal is to combine the advantages of conventional holograms (i.e. extremely high visual quality and realism, support for all depth queues and for multiple observers at no computational cost, space efficiency, etc.) with the advantages of today’s computer graphics capabilities (i.e. interactivity, real-time rendering, simulation and animation, stereoscopic and autostereoscopic presentation, etc.). The results of these investigations are presented in this chapter

Holographic reality: enhancing the artificial reality experience throuhg interactive 3D holography

Holography was made know by several science-fiction productions, however this technology dates back to the year 1940. Despite the considerable age of this discovery, this technology remains inaccessible to the average consumer. The main goal of this manuscript is to advance the state of the art in interactive holography, providing an accessible and low-cost solution. The final product intends to nudge the HCI com munity to explore potential applications, in particular to be aquatic centric and environmentally friendly. Two main user studies are performed, in order to determine the impact of the proposed solution by a sample audience. Provided user studies include a first prototype as a Tangible User Interface - TUI for Holographic Reality - HR Second study included the Holographic Mounted Display - HMD for proposed HR interface, further analyzing the interactive holographic experience without hand-held devices. Both of these studies were further compared with an Augmented Reality setting. Obtained results demonstrate a significantly higher score for the HMD approach. This suggests it is the better solution, most likely due to the added simplicity and immersiveness features it has. However the TUI study did score higher in several key parameters, and should be considered for future studies. Comparing with an AR experience, the HMD study scores slightly lower, but manages to surpass AR in several parameters. Several approaches were outlined and evaluated, depicting different methods for the creation of Interactive Holographic Reality experiences. In spite of the low maturity of holographic technology, it can be concluded it is comparable and can keep up to other more developed and mature artificial reality settings, further supporting the need for the existence of the Holographic Reality conceptA tecnologia holográfica tornou-se conhecida através da ficção científica, contudo esta tecnologia remonta até ao ano 1940. Apesar da considerável idade desta descoberta, esta tecnologia continua a não ser acessíveil para o consumidor. O objetivo deste manuscrito é avançar o estado de arte da Holografia Interactiva, e fornecer uma solução de baixo custo. O objetivo do produto final é persuadir a comunidade HCI para a exploração de aplicações desta tecnologia, em particular em contextos aquáticos e pró-ambientais. Dois estudos principais foram efetuados, de modo a determinar qual o impacto da solução pro posta numa amostra. Os estudos fornecidos incluem um protótipo inicial baseado numa Interface Tangível e Realidade Holográfica e um dispositivo tangível. O segundo estudo inclui uma interface baseada num dispositivo head-mounted e em Realidade Holográfica, de modo a analisar e avaliar a experiência interativa e holográfica. Ambos os estudos são comparados com uma experiência semelhante, em Realidade Aumentada. Os resultados obtidos demonstram que o estudo HMD recebeu uma avaliação significante mel hor, em comparação com a abordagem TUI. Isto sugere que uma abordagem "head-mounted" tende a ser melhor solução, muito provavelmente devido às vantagens que possui em relação à simplicidade e imersividade que oferece. Contudo, o estudo TUI recebeu pontuações mais altas em alguns parâmetros chave, e deve ser considerados para a implementação de futuros estudos. Comparando com uma experiência de realidade aumentada, o estudo HMD recebeu uma avaliação ligeiramente menor, mas por uma margem mínima, e ultrapassando a AR em alguns parâmetros. Várias abordagens foram deliniadas e avaliadas, com diferentes métodos para a criação de experiências de Realidade Holográfica. Apesar da pouca maturidade da tecnologia holográfica, podemos concluir que a mesma é comparável e consegue acompanhar outros tipos de realidade artificial, que são muito mais desenvolvidos, o que suporta a necessidade da existência do conceito de Realidade Holográfica

HoloBeam: Paper-Thin Near-Eye Displays

An emerging alternative to conventional Augmented Reality (AR) glasses designs, Beaming displays promise slim AR glasses free from challenging design trade-offs, including battery-related limits or computational budget-related issues. These beaming displays remove active components such as batteries and electronics from AR glasses and move them to a projector that projects images to a user from a distance (1-2 meters), where users wear only passive optical eyepieces. However, earlier implementations of these displays delivered poor resolutions (7 cycles per degree) without any optical focus cues and were introduced with a bulky form-factor eyepiece (50 mm thick). This paper introduces a new milestone for beaming displays, which we call HoloBeam. In this new design, a custom holographic projector populates a micro-volume located at some distance (1-2 meters) with multiple planes of images. Users view magnified copies of these images from this small volume with the help of an eyepiece that is either a Holographic Optical Element (HOE) or a set of lenses. Our HoloBeam prototypes demonstrate the thinnest AR glasses to date with a submillimeter thickness (e.g., HOE film is only 120 um thick). In addition, HoloBeam prototypes demonstrate near retinal resolutions (24 cycles per degree) with a 70 degrees-wide field of view.Comment: 15 pages, 18 Figures, 1 Table, 1 Listin

Hardware implementations of computer-generated holography: a review

Computer-generated holography (CGH) is a technique to generate holographic interference patterns. One of the major issues related to computer hologram generation is the massive computational power required. Hardware accelerators are used to accelerate this process. Previous publications targeting hardware platforms lack performance comparisons between different architectures and do not provide enough information for the evaluation of the suitability of recent hardware platforms for CGH algorithms. We aim to address these limitations and present a comprehensive review of CGH-related hardware implementations

A Survey of Signal Processing Problems and Tools in Holographic Three-Dimensional Television

Cataloged from PDF version of article.Diffraction and holography are fertile areas for application of signal theory and processing. Recent work on 3DTV displays has posed particularly challenging signal processing problems. Various procedures to compute Rayleigh-Sommerfeld, Fresnel and Fraunhofer diffraction exist in the literature. Diffraction between parallel planes and tilted planes can be efficiently computed. Discretization and quantization of diffraction fields yield interesting theoretical and practical results, and allow efficient schemes compared to commonly used Nyquist sampling. The literature on computer-generated holography provides a good resource for holographic 3DTV related issues. Fast algorithms to compute Fourier, Walsh-Hadamard, fractional Fourier, linear canonical, Fresnel, and wavelet transforms, as well as optimization-based techniques such as best orthogonal basis, matching pursuit, basis pursuit etc., are especially relevant signal processing techniques for wave propagation, diffraction, holography, and related problems. Atomic decompositions, multiresolution techniques, Gabor functions, and Wigner distributions are among the signal processing techniques which have or may be applied to problems in optics. Research aimed at solving such problems at the intersection of wave optics and signal processing promises not only to facilitate the development of 3DTV systems, but also to contribute to fundamental advances in optics and signal processing theory. © 2007 IEEE

3D Capture and 3D Contents Generation for Holographic Imaging

The intrinsic properties of holograms make 3D holographic imaging the best candidate for a 3D display. The holographic display is an autostereoscopic display which provides highly realistic images with unique perspective for an arbitrary number of viewers, motion parallax both vertically and horizontally, and focusing at different depths. The 3D content generation for this display is carried out by means of digital holography. Digital holography implements the classic holographic principle as a two‐step process of wavefront capture in the form of a 2D interference pattern and wavefront reconstruction by applying numerically or optically a reference wave. The chapter follows the two main tendencies in forming the 3D holographic content—direct feeding of optically recorded digital holograms to a holographic display and computer generation of interference fringes from directional, depth and colour information about the 3D objects. The focus is set on important issues that comprise encoding of 3D information for holographic imaging starting from conversion of optically captured holographic data to the display data format, going through different approaches for forming the content for computer generation of holograms from coherently or incoherently captured 3D data and finishing with methods for the accelerated computing of these holograms