This PDF file contains the front matter associated with SPIE Proceedings Volume 9006, including the Title Page, Copyright information, Table of Contents, Introduction (if any), and Conference Committee listing.

Manipulating light with optical gratings based on volume Holographic Optical Elements (vHOEs), also known as volume Bragg gratings, has the advantage to reconstruct only the first diffraction order and hence provide high diffraction efficiencies and angular selectivity. In addition, they offer the further benefit to be fully transparent in the off- Bragg condition like it is required in optical combiners. We present the latest status of our instant-developing photopolymer film technology (Bayfol® HX) and show beneficial recording parameters - specifically we discuss the challenges to record transmission vHOEs and how to overcome them. Experimental results on color transmission recordings are shown and it is demonstrated that those match perfectly to Kogelniks coupled wave theory. It is recommended to adopt the dynamic range of the recording media by proper choice of recording dosage, recording power, beam ratio and photopolymer film type to the desired transmission vHOE design.

Recent improvements in key foundation technologies are set to potentially transform the field of Display Holography. In particular new recording systems, based on recent DPSS and semiconductor lasers combined with novel recording materials and processing, have now demonstrated full-color analogue holograms of both lower noise and higher spectral accuracy. Progress in illumination technology is leading to a further major reduction in display noise and to a significant increase of the clear image depth and brightness of such holograms. So too, recent progress in 1-step Direct-Write Digital Holography (DWDH) now opens the way to the creation of High Virtual Volume Displays (HVV) - large format full-parallax DWDH reflection holograms having fundamentally larger clear image depths. In a certain fashion HVV displays can be thought of as providing a high quality full-color digital equivalent to the large-format laser-illuminated transmission holograms of the sixties and seventies. Back then, the advent of such holograms led to much optimism for display holography in the market. However, problems with laser illumination, their monochromatic analogue nature and image noise are well cited as being responsible for their failure in reality. Is there reason for believing that the latest technology improvements will make the mark this time around? This paper argues that indeed there is.

Direct write digital holography technique (DWDH) using single pulsed exposures of 440nm pulsed laser has been applied to record master holograms on commercially available photoresists (ma-P1200 and Shipley 1800 series) of different thickness. Method for numerical evaluation of hologram quality, based on diffraction intensity measurement (reflected beam), was proposed and verified. It was found that all investigated photoresists: ma-P1205, ma-P1225 and S1805, were sensitive enough to record holographic structures at low single pulse laser exposures from the range 3.3 ÷ 19.5 mJ/cm² . Best quality holograms with well – structured holopixels (hogels) were observed on 0.67 μm thick ma- P1205 photoresist exposed to 11.4 mJ/cm² and on 0.65 μm thick S1805 photoresits exposed to 13 mJ/cm², where corresponding measured diffraction intensity had its maximum value. In the case of thicker photoresists (ma-P1225, 3.33 μm), comparable quality of the hogel structure was found in the interval 9.8 – 13 mJ/cm².

Investigation has shown a potential of single pulsed laser exposures to record good quality master holograms on commercially available photoresists applying at least 5 times lower exposures values as compared to CW laser exposures usually used to expose photoresist materials in holographic applications. That opens a possibility to use pulsed lasers for quick origination of master-originals for embossed holograms applying DWDH technique or analogue methods.

Various superimposed chirped relief gratings, acting as diffracting holographic lenses, were photo-inscribed on azopolymer films upon exposure to the interference pattern of a plane and a curved laser light wavefronts. Depending on the configuration used, this resulted in incident light being focused independently of polarization along the 0th or 1st diffracted order of the grating. The focal point and focalization angle of the resulting holographic lenses were easily tuned during the fabrication process.

Almost all current collinear holographic storage systems record and reproduce the amplitude information but ignore the phase information. To utilize phase information as the useful data is a significant study. Instead of amplitude modulation, using phase encoding and decoding to get phase information is one way to raise storage density. By adding phase encoding to the amplitude encoding, we realized the phase modulation. To reduce the computation load we simplified multilayer phase-scale model to binary 0 and π phase model. By controlling the proportion of 0 and π phase, different phase modulation models can be represented. In the simulation, we use the angular spectrum theory to build the system mathematical model. We got an effective range of the phase modulation called degree of freedom curve of phase encoding, which can promise both low bit-error-rate (BER) and high code rate. Using this curve, we can make phase encoding more efficiently. Once the dynamic response range of the materiel, the gray levels of phase encoding, and the demanded BER determined, we can calculate the degree of freedom curve to prepare for the followed phase encoding.

Polymers that undergo to photo-Fries reaction show a remarkable modulation of the refractive index that makes them interesting in the field of volume holography. In order to understand the mechanism of the change in the refractive index we performed theoretical calculations (DFT) on model molecules. The results show that the modulation can be ascribed to a change in the polymer density upon photo-reaction whereas the contribution due to a change in molecular polarizability is small. The theoretical conclusions have been supported by experimental results on two polymers: Polyformyloxide styrene (PFS) and polyacetoxystyrene (PAS).

The realization of a commercial holographic data storage device has remained elusive for many decades. The most recent efforts were by InPhase Technologies between 2001 and 2009 resulting in 52 functioning prototypes capable of 300GB/disk and 20MB/s transfer rates. Despite being the world’s first fully functional holographic drives, the primary competitor to holographic archive storage at that time, LTO, had already achieved 800GB and 120MB/in 2008; and by 2010, LTO had achieved 1.5TB and 140MB/s. This left InPhase at a competitive disadvantage to LTO archive solutions despite other strengths such as robustness, random access, and longer-term archive lifetime.

Looking into the future, holographic data storage must be highly competitive with tape in three critical areas: cost/TB, capacity/footprint, and transfer rate. If this can be achieved, holographic data storage would become a superior solution given the low latencies and overall robustness to propel it into being the archive storage front-runner. New technology advancements by Akonia Holographics have enabled the potential for ultra-high capacity holographic storage devices that are capable of world record bit densities of over 2Tbit/in², 200-300MB/s transfer rates, and a media cost less than $10/TB in the next 5 years. A demonstration platform based on these new advances has been designed and is currently being built by Akonia to progressively demonstrate bit densities of 2Tb/in², 4Tb/in², and 8Tb/in² over the next year.

We describe imaging capabilities of a 0.2 m membrane diffractive primary (DOE) used as a key element in FalconSat-7, a space-based solar telescope. Its mission is to take an image of the Sun at the H-alpha wavelength (656nm) over a narrow bandwidth while in orbit. In this case the DOE is a photon sieve which consists of billions of tiny holes, with the focusing ability dependent on an underlying Fresnel zone geometry. Uniform radial expansion/contraction of the substrate due to temperature or relative humidity change will result in a shift in focal length without introducing errors in phase of the transmitted wavefront and without a decrease in efficiency. We will also show that while ideally the DOE surface should be held flat to within 5.25 microns, an opto-mechanical analysis showed that local deformations up to 32 microns are possible without significantly degrading the image quality.

Electronic speckle pattern interferometry (ESPI) is a powerful technique for differential shape measurement with submicron resolution. Using spatial phase-shifting (SPS), no moving parts are required, allowing frame acquisition rates limited by camera hardware. We present ESPI images of 1 megapixel resolution at 500 fps. Analysis of SPS data involves complex, time-consuming calculations. The graphics processing units found in state-of-the-art personal computers have exceptional parallel processing capabilities, allowing real-time SPS measurements at video frame rates. Deformation analysis at this frame rate can be used to analyze transient phenomena such as transient temperature effects in integrated circuit chips or during material processing.

Progress has been made towards the development of a flexible true color holographic imaging device for direct optical biopsy. This can potentially be used for surgical techniques employing direct visualization, including endoscopy and laparoscopy. A novel panchromatic ‘ultrahigh precision’ recording media, with a thin layer of ultrafine grain of silver halide crystals of 10-20 nm average diameter, has been utilized. The significance of the development so far, has been the ability to emulate ‘color optical biopsy’ providing useful information of ‘medical relevance’.

Adaptive optics (AO) in astronomical imaging is a technique to improve the quality of image by compensating aberrations induced by atmospheric turbulence. Digital holographic AO (DHAO) is one attractive option to implement AO scheme because it is capable of directly measuring the phase profile of aberration without complicated calculation or loss of resolution of CCD. Hence, if applicable, DHAO is expected to have advantages over traditional AO systems. Recent development of self-interference incoherent digital holography (SIDH) makes it possible to apply the concept of DHAO for an astronomical application where the illumination is incoherent and cannot be controlled. We have investigated the image characteristics according to various parameters of SIDH AO to derive optimum condition or design of the system. We observe not only well-known super-resolution property of SIDH but also interesting and significant improvement of noise behavior by aberration compensation. Because of many beneficial features, we expect that SIDH AO will be a useful tool for astronomical imaging.

In this work multiwavelength digital holography, originally applied to calculate the volume displacement of various macroscopic topographic surface features, is now extended to the case of microscopic objects. Accurate measurements of volume displacement for macroscopic surface features has been achieved using long synthetic wavelengths up to several millimeters, generated via tunable IR laser sources. Microscopic volume measurements are performed via digital holographic microscopy using HeNe and Ar⁺ ion lasers to generate very short synthetic wavelengths. Practical methods of implementation are considered, including wavelength selection error and the geometric effects of both Michelson and Mach-Zehnder recording configurations on phase measurement. Results include comparisons to standard metrology tools, including 1D profilometry and white light interferometry.

Unplanned images recorded within holographic space are of candid interest that can reshape audience definition crossing intellectual boundaries. This paper details three examples of off-axis Pulsed Laser transmission holograms that involve holographic portraits. These are movie director Martin Scorsese, former Royal Photographic Society President Mike Austin and a unique recently discovered early pulsed recording of Nick Phillips together with Anton Furst recorded in 1977. Each example was made when operating conditions for the pulsed ruby lasers were optimum, offering a coherence of several meters time-compressed into 25 ns. This gave rise to not only the portrait capture but also others present during the recording session inside the room. This optimum condition captured more than was intended resulting in images that, until now, have remained un-documented.

In this series of digital art holograms and lenticulars, we are examining different kinds of movement inside the digital holographic space explored by Elizabeth Sandford-Richardson, a visual performance artist. During the process of capturing the image, we used the HoloCam Portable Light System, equipped with Canon and Nikon cameras positioned at different heights and angles, in order to improve the rendering of the holographic space. Based on the “Performativity of Performance Documentation” a notion introduced by Philip Auslanderi we revisit some authors that have been working in the “theatrical” practise, mainly in photography, adding the possibility of movement in 3D space. We must realise that the movement of the viewer in front of a digital holographic image creates the performance that he/she is looking at. We should consider the physical space, outside the hologram, and this kind of “performance acts”, also part of the work. In summary, we propose a reflection on the digital holographic space, time, movement and its place in contemporary art.

Only nature can create, whereas humans can only re-create. This article is an exploration of synergies between art and science in digital holography in relation to art practice and the making of holograms as art works. This is achieved through involvement in the re-creation of a real object (a telescope) as a case study. A digital three-dimensional model suitable for holographic hard copy re-creation is produced. To explore special and immersive environment, real geographical landscape background from Google Earth is added to the model. After a brief introduction to visual art within the context of two and three-dimensional imaging in the form photography and holography, the whole process of producing the three-dimensional model and the environment in which it should be presented, ready for holographic printing is explained.

Most existing holographic display methods concentrate on real object reconstruction, but there is a lack of research on object stories (revealing and presenting histories). To address this challenge, we propose a method, called 4 ‘ER’ (leader, manager, implementer, presenter) to experience and respond objects in a special immersive environment. The key innovation of the 4’ER’ method is to introduce the stories (political, historical, etc.) into hard copy holography, so as to synergy art and science for museum objects display. The hologram of an imitation of a blue and white porcelain jar from The Palace Museum, Beijing, China has been made, showing good performance and reflecting different pathway to knowledge.

A holographic stereograms generation technique based on multi-view displays does not require diffraction calculation when generating holographic stereograms from multiple perspective projections of real objects. However, a viewing area was limited when the spatial frequency of the quadratic phase distribution exceeds the Nyquist frequency determined by the pixel pitch of the spatial light modulator. In this study, we improved the technique by introducing a spherical lens on the hologram display plane to provide a quadratic phase distribution to wavefronts. Because of random phase distributions that were added to the parallax images to obtain smooth motion parallax, speckle noise was observed in reconstructed images. To reduce the speckle noise, the spatial bandwidths of the wavefronts were limited. The proposed technique was verified experimentally.

In computer-generated holograms (CGHs), various methods to generate holograms of actual objects have been proposed. One method uses the 3D information of actual objects obtained by one range sensor to generate a hologram. However, this method is unable to express occlusion because the 3D information is measured from only one viewpoint. Therefor, re-capturing 3D information is necessary to make CGHs from another viewpoint in this method. To overcome these problems, we have proposed a method that generates models of actual objects in a computer using two or more range sensors. In this method, CGHs are calculated by using multi-view images (MVIs) rendered from object models, which enables the occlusion to be expressed correctly. However, determination brightness values is unable to be performed on the whole object model because the luminance images are insufficient. This makes it difficult to generate CGHs from arbitrary viewpoints at one time. In this paper, we propose a method using additional digital cameras with range sensors to generate CGHs of actual objects from arbitrary viewpoints. This method determines the brightness values of the whole model using pictures taken by the additional cameras. The proposed method is advantageous in that re-capturing 3D information is unnecessary when CGHs are generated from another viewpoint. This method calculates CGHs with MVIs rendered from the model having brightness values. Results of computer simulations and optical reconstruction showed that it was possible to generate CGHs of actual objects with occlusion from arbitrary viewpoints.

Holography is one of the three-dimensional technology. Light waves from an object are recorded and reconstructed by using a hologram. Computer generated holograms (CGHs), which are made by simulating light propagation using a computer, are able to represent virtual object. However, an enormous amount of computation time is required to make CGHs. There are two primary methods of calculating CGHs: the polygon-based method and the point-based method. In the polygon-based method with Fourier transforms, CGHs are calculated using a fast Fourier transform (FFT). The calculation of complex objects composed of multiple polygons requires as many FFTs, so unfortunately the calculation time become enormous. In contrast, in the point-based method, it is easy to express complex objects, an enormous calculation time is still required. Graphics processing units (GPUs) have been used to speed up the calculations of point-based method. Because a GPU is specialized for parallel computation and CGH calculation can be calculated independently for each pixel. However, expressing a planar object by the point-based method requires a signi cant increase in the density of points and consequently in the number of point light sources. In this paper, we propose a fast calculation algorithm to express planar objects by the point-based method with a GPU. The proposed method accelerate calculation by obtaining the distance between a pixel and the point light source from the adjacent point light source by a difference method. Under certain speci ed conditions, the difference between adjacent object points becomes constant, so the distance is obtained by only an additions. Experimental results showed that the proposed method is more effective than the polygon-based method with FFT when the number of polygons composing an objects are high.

We proposed a fast scheme for computer-generated holography (CGH) to mix 3D scenes. The objects in the proposed include the real and virtual objects. Make a point cloud model of real object, and then converted to a triangular mesh model. And mix the triangular mesh model with virtual 3D object mesh models. Using the angular spectrum method to generated hologram, and it is convenient to accelerating with GPU.

An analytic examination of 3D holography under a 90° recording geometry was carried out earlier in which 2D spatial Laplace transforms were introduced in order to develop transfer functions for the scattered outputs under readout [1,2]. Thereby, the resulting reconstructed output was obtained in the 2D Laplace domain whence the spatial information would be found only by performing a 2D Laplace inversion. Laplace inversion in 2D was attempted by testing a prototype function for which the analytic result was known using two known inversion algorithms, viz., the Brancik and the Abate [2]. The results indicated notable differences in the 3D plots between the algorithms and the analytic result, and hence were somewhat inconclusive. In this paper, we take a closer look at the Brancik algorithm in order to understand better the implications of the choices of key parameters such as the real and imaginary parts of the Bromwich contour and the grid sizes of the summation operations. To assess the inversion findings, three prototype test cases are considered for which the analytic solutions are known. For specific choices of the algorithm parameters, optimal values are determined that minimize errors in general. It is found that even though errors accumulate near the edges of the grid, overall reasonably accurate inversions are possible to obtain with optimal parameter choices that are verifiable via cross-sectional views. Further work is ongoing whereby the optimized algorithm is to be applied to the 3D holography problem.

The MIT Mark IV holographic display system employs a novel anisotropic leaky-mode spatial light modulator that allows for the simultaneous and superimposed modulation of red, green, and blue light via wavelength-division multiplexing. This WDM-based scheme for full-color display requires that incoming video signals containing holographic fringe information are comprised of non-overlapping spectral bands that fall within the available 200 MHz output bandwidth of commercial GPUs. These bands correspond to independent color channels in the display output and are appropriately band-limited and centered to match the multiplexed passbands and center frequencies in the frequency response of the mode-coupling device. The computational architecture presented in this paper involves the computation of holographic fringe patterns for each color channel and their summation in generating a single video signal for input to the display. In composite, 18 such input signals, each containing holographic fringe information for 26 horizontal-parallax only holographic lines, are generated via three dual-head GPUs for a total of 468 holographic lines in the display output. We present a general scheme for full-color CGH computation for input to Mark IV and furthermore depict the adaptation of the diffraction specific coherent panoramagram approach to fringe computation for the Mark IV architecture.

Compressive sensing is a new alternative to the conventional Fresnel approach for digital holographic reconstruction for sparse objects, and can show improved performance with respect to image quality and the depth of focus. In this work, we experimentally investigate the performance of the compressive sensing reconstruction approach and compare it with the Fresnel transform and the non-paraxial and paraxial transfer function back-propagation approach. The compressive sensing technique used is the so-called Two-Step Iterative Shrinkage/Thresholding algorithm. A He-Ne laser of 543.5 nm is used as the light source and a Gabor holographic recording system is used as the experimental setup. The test object comprises a dandelion seed parachute with few wings. We capture the holograms at several recording distances and then reconstruct the image using each method. Over the range of recording distances used, the non-paraxial and paraxial transfer function back-propagation approach yields identical results. We evaluate the depth resolution of the compressive sensing algorithm and compare it with that of the Fresnel approach and the non-paraxial back-propagation approach.

We have recently developed an electronic holography reconstruction system by tiling nine 4Kx2K liquid crystal on silicon (LCOS) panels seamlessly. Magnifying optical systems eliminate the gaps between LCOS panels by forming enlarged LCOS images on the system’s output lenses. A reduction optical system reduces the tiled LCOS images to the original size, returning to the original viewing zone angle. Since this system illuminates each LCOS panel through polarized beam splitters (PBS) from different distances, viewing-zone-angle expansion was difficult since it requires illumination of each LCOS panel from different angles. In this paper, we investigated viewing-zone-angle expansion of this system by integrating point light sources in the magnifying optical system. Three optical fibers illuminate a LCOS panel from different angles in time-sequential order, reconstructing three continuous viewing-zones. Full-color image reconstruction was realized by switching the laser source among R, G, and B colors. We propose a fan-shaped optical fiber arrangement to compensate for the offset of the illumination beam center from the LCOS panel center. We also propose a solution for high-order diffraction light interference by inserting electronic shutter windows in the reduction optical system.

In digital holography, computing a focused image of an object requires a prior knowledge of the distance of the object from the camera. When this distance is not known, it is necessary to repeat the image reconstruction at a range of distances followed by evaluation of each image with a sharpness metric to determine the in-focus distance of the object. Here, we present a method to nd the focus distance by processing the image transverse to the object plane instead of the processing in the image plane as it is usually done. Since the reconstructed hologram image is spatially symmetric around the focus point along the propagation axis, simply nding the symmetry points in the image cross-section speci es the focus location, and no other sharpness metrics are necessary to use. Also with this method, it is possible to nd the focus distances of multiple objects simultaneously, including the phase only objects without any staining. We will present the simulations and the experimental results obtained by a digital holographic microscope.

In three dimensional display technologies, studies on measuring accommodation and convergence responses to reconstructed images have been reported. However, the physiological characteristics of responses to reconstructed electro-holographic images are not clearly known. In this research, static responses to holographic images and real targets were measured. In addition to measuring responses, tests were conducted to evaluate the depths of reconstructed images in comparison with those of real targets, subjectively. A measurement system consisting of an electro-holographic display, real targets, and an auto refractometer was fabricated to measure accommodation and convergence responses. The display for reconstructing holographic images was a binocular eyepiece - type electro-holographic display based on a Fourier transform optical system. It was confirmed by a camera in which images were located at correct depth and had correct parallax. The target was shaped like a Maltese cross and presented in positions that were 0.5, 1.0, 1.5 and 2.0 diopters from the subjects’ eyes. To avoid the influence of objects except targets, all experimentations were done in a dark room. Regarding the results of the measurements, it was confirmed that accommodation and convergence responses to holographic images varied depending on the position of the targets, and the behaviors of holographic images were similar to those of real targets. In addition, results of subjective evaluation showed that holographic images were recognized at nearly the same positions as real targets. Therefore, subjects were able to perceive holographic images at nearly the same positions as real objects in stereoscopic vision.

In this paper we present the method for fast computer generation hologram (CGH) of the long depth object using multiple wavefront recording planes (WRP). The wavefront recording planes are placed between object plane and hologram plane. Each WRP records the wavefront from a section of object. For a long depth object, multiple WRPs can reduce the calculation time and also enhance the quality of reconstruction object in comparison with those ones of single WRP. The hologram of object can be real time generated by out proposed method.

In general, digital holography means a technology to measure an object wave by using a focal plane array (FPA) sensor. Since the limitation of the dimension of the FPA sensor, the field of view obtained by the FPA sensor is usually very narrow. Many methods have been proposed to increase the field of view of measurement. One simple solution is the synthesis of the holograms with small apertures, where each of them is measured by the FPA sensor respectively. If we imagine specific applications such as 360-degree table-top digital holographic display, the large field of view of the object is required to present the three-dimensional contents to the observer who may change his position dynamically. In this paper, we use two-axis rotation stage for acquisition of the object wave with large field of view. In our system, the optics including a laser and a CCD sensor are fixed and the object is mounted on the rotation stage. During the rotation of the object, the holograms are taken sequentially and the object wave over the hemispherical surface in k-space is obtained. The increase of solid angle of the measured hologram means the increase of acquired angular spectrum of interested objects. The resolution of the measurement is closely related with the numerical aperture and the data with fine resolution is expectable. But since it is not easy to match the relative phases of the each hologram, unfortunately the enhancement of the resolution in the reconstructed object wave is negligible.

Numerical results are presented from the behavior of diffraction gratings through micro-holographic spatially localized areas, which consist of micro-coded areas with sinusoidal profile gratings. The random distribution of the micro areas, introduces diffracted orders a random modulation, we observed a characteristic profile of randomness. This is a study of the behavior of the random distribution as a function of the micro-area form where the gratings are generated.

Phase liquid crystal spatial light modulators (LC SLM) are widely used in optical applications such as real-time imaging of holograms and diffractive optical elements, which require high stability and linearity of phase modulation. However state of the art LC SLM with high resolution use digital voltage addressing scheme which, unfortunately, leads to phase fluctuations in time period of one frame. Fluctuations characteristics depend on SLM voltage addressing sequence used. We report results of measurement of phase characteristics of LC SLM “HoloEye PLUTO VIS”. This SLM is supplied with three different addressing sequences: “18-6”, “5-5” and “0-6”. Dynamics of phase fluctuations were measured for all signal values (0-255) with temporal resolution of 0.5 ms in time period of one frame for available addressing sequences. Default sequence “18-6” provided phase deviation 0.24 pi. Lowest deviation 0.07 pi was achieved with sequence “0-6”. Due to high periodicity of fluctuations it is possible to implement synchronization of SLM and registering camera or light source to reduce fluctuation effects. This was experimentally implemented using DVI video signal for synchronization of SLM and camera. With its application minimum phase deviation 0.013 pi was achieved with sequence “18-6” which is 5 times lower than achievable without synchronization.

Holographic gratings recorded in photoresist, are used by common techniques of lithography, for writing on glass. We present a study of the technique used to erode the glass using hydrofluoric acid and copy the holographic element on the glass. We observe that holograms written in glass are very strong and durable. The behavior of the dispersion caused by the glass erosion also is studied.

Although various 3-D head mounted displays (HMDs) using stereograms have been implemented, extended usage of those systems cause discomfort, fatigue and tiredness because stereogram do not satisfy all 3-D visual cues: accommodation, vergence, and parallax. On the other hand, electro-holography enables observers to view natural 3-D images with minimal discomfort due to satisfying these necessary cues. This time, we fabricated a small sized full-color holographic display system with a type of binocular eyepiece for the base of the wearable system. In this paper, we describe the structure of our system and the proposed calibration method for the arrangement of the optical parts. This calibration plays an important role in the accuracy of the reconstructed images. The main optical parts are combined to a single component to keep the exact arrangement, so this system is semi-portable and can be used everywhere with only a little adjustment. The system has the slide structure between left and right view point like binoculars to eliminate the influence of individual interpupillary distances (PDs). The field sequential color method enables the system to reconstruct full-color images by this display system. The light source is a full-color LED covered with a sharpened fiber and the tip of the fiber works as an almost ideal point light source. The results of the subjective experiments show that reconstructed full-color images are statistically located at the correct depths and satisfy correct accommodation and vergence without the influence of individual PDs.

The preparation of photosensitive films of quail albumen (protein), applying as oxidizing agent, green iron ammonium citrate. Exposed to a He-Cd laser, λ = 442nm, transmission holograms were recorded. We obtained the diffraction patterns reconstructed with He-Ne laser, λ=632.8nm and measuring diffraction efficiencies for first order as a function of exposure energy. Holographic gratings made with these materials exhibit behaviour of self develop. We analyse the experimental results.

We describe fluorescent holograms were made with photosensitive films of albumin (protein) quail, used as modified matrices. Albumin is mixed with acrylamide and eosin Y. Therefore, prepare a photosensitive emulsion and solid hydrated with the ability to phase transmission holograms and volume (VPH). Eosin Y is a fluorescent agent that acts as a photo-sensitizing dye which stimulates the polymerization of acrylamide. To record the interference pattern produced by two waves superimposed on the modified matrix, we use a He-Cd laser. To reconstruct the diffraction pattern is observed with He- Ne laser, λ = 632.8nm, the material is self-developing properties. Measure the diffraction efficiency of the diffracted orders (η_{[-1, +1]}) as a function of exposure energy. We work with various thicknesses and measure the variation of the refractive index using the coupled wave theory of Kogelnik, the holographic gratings meet Bragg condition.

One of the natural most employed within the food industry are pigments of betalains by their solubility in water to give desired colorations in processed foods such as beverages, dairy, meat. However, this research shows that this type of pigments can be used as photosensitizing agents in the field of holographic recording materials.

Carotenoids pigments presents in pineapple can be more than just natural dyes, which is one of the applications that now at day gives the chemical industry. In this research shown that can be used in implementing of holographic recording Films. Therefore we describe the technique how to obtain this kind of pigments trough spay drying of natural pineapple juice, which are then dissolved with water in a proportion of 0.1g to 1mL. The obtained sample is poured into glass substrates using the gravity method, after a drying of 24 hours in laboratory normal conditions the films are ready. The films are characterized by recording transmission holographic gratings (LSR 445 NL 445 nm) and measuring the diffraction efficiency holographic parameter. This recording material has good diffraction efficiency and environmental stability.

We have investigated the floating full color image display with the computer-generated hologram (CGH). The floating image, when utilized as a 3D display, gives strong impression to the viewer. In our previous study, to change the CGH shape from the flat type to the half cylindrical type, the floating image from the output CGH has the nearly 180 degrees viewing angle. However, since the previous CGH does not have wavelength-selectivity, reconstructed image only has a single color. Also, the huge calculation amount of the fringe pattern is big problem. Therefore, we now propose the rainbow-type computer generated alcove hologram. To decrease the calculation amount, the rainbow hologram sacrifices the vertical parallax. Also, this hologram can reconstruct an image with white light. Compared with the previous study of the Fresnel type, the calculation speed becomes 165 times faster. After calculation, we print this hologram with a fringe printer, and evaluate reconstructed floating full color images. In this study, we introduce the computer-generated rainbow hologram into the floating image display. The rainbow hologram can reconstruct full color image with white light illumination. It can be recorded by using a horizontal slit to limit the vertical parallax. Therefore, the slit changes into the half cylindrical slit, the wide viewing angle floating image display can reconstruct full color image.

Holographic data storage (HDS) is a next-generation optical storage that uses the principles of holography. The multiplex holographic recording method is an important factor that affects the recording capacity of this storage. Various multiplex recording methods have been proposed so far. In this study, we focus on shift multiplexing with spherical waves and propose a method of shift multiplex recording that combines the peristrophic multiplexed recording. Simulation and experimental verification shows that the proposed method is effective in principle.

Holographic data storage (HDS) is a promising technology that has a huge capacity. A multiplexing method plays a significant role in increasing the data capacity. Various multiplexing methods have been researched so far. In this paper, we proposed shift-peristrophic multiplexing using spherical reference beam and experimentally verified that this method is efficiently increase the data capacity. A series of holograms was recorded with shift multiplexing and peristrophic multiplexing with the rotation of the material's surface. This method can realize more than 1 Tbits/inch² data density recording..

The wavefront printer is an equipment to produce computer-generated holograms (CGH) as a volume hologram. This printer records the wavefront generated by spatial light modulator (SLM). We propose a novel technique for applying phase-only SLM to the wavefront printer without losing the advantage of the wide space-band product of phase modulation. The phase-only SLM commonly has the problem of degradation of generated wavefronts because of coding noise due to phase only modulation. To reduce the noise, a technique is presented in order to partially modulate amplitude of recording light in phase-only SLM.

High-definition computer holography based on the polygon-based method commonly uses the silhouette method to shield light behind objects for hidden surface removal. However, the light-shielding is not perfect and causes leakage light passing through many gaps between silhouette-shaped masks. Although we have proposed the principle of more rigorous technique to remove the leakage light, the technique has never been applied to the actual high-definition computer holography because of its long computation time. We propose some techniques to reduce the computation time and apply the rigorous technique to high-definition computer holography. A CGH created by the proposed method is demonstrated.

Viewing angle of the conventional flat hologram is not very large (less than 180°) attributed to their planar observation surface. If we want to synthesize a wide view computer generated hologram, a numerical simulation of the diffraction on the non-planar observation surfaces is required, computer generated cylindrical hologram (CGCH) can be a solution. Approximately 2,500 object points were used for this research. We have realized a CGCH that is viewable in 360°. However, the heavy computation load is one of the issues. Therefore, we propose a fast calculation method for a computer generated cylindrical hologram by the use of wave-front recording surface. The wave-front recording surface is placed between the object data and a CGCH. When the wave-front recording surface is placed close to the object, the object light passes through a small region on the wave recording surface. Therefore the computational complexity for the object light is very small. We can obtain a CGCH to execute diffraction calculation from the wave-front recording surface, propagating the recorded optical field of the wave-front recording surface to the cylindrical hologram surface using only two FFT operations and hence is much faster.

In this paper, we present the development of full color holographic optical element for light-emitting diodes display application using a photopolymer. The reflection HOE was evaluated by measuring the diffraction efficiencies of holographic volume gratings recorded individually at 633 nm, 532 nm, and 473nm wavelengths. The spectral characterization of the holographic optical element, recorded using a combined single beam, and recorded using sequential beam, was carried out. Practical methods for fabrication of high efficiency holographic optical element by single layer photopolymer were developed. As the reconstruction light source of the hologram, light-emitting diodes of 632nm, 523nm and 465nm in wavelength was used. The results represent a strong confirmation that the special recording method using photopolymer can be employed in future commercial holographic applications.

In this work we describe an experimental technique to measure the birefringence of the cellophane film that has good behavior as half wave retarder. This technique is achieved when the film is placed in a polariscope that consists of a light source and properly arranged polarizing elements and a system of fringes is observed. Using Jones formalism for the system the birefringence appears in the phase term of harmonic functions. Some experimental results are shown.

In this work we propose a phase material based on fish gelatin from Norland Products© mixed with ammonium dichromate deposited on a glass substrate. The photosensitive film has 110 mm thickness. In this material we record low frequency (264 lines/mm) holographic gratings using a λ=532 nm from an Ar laser and reconstruct the image with λ=594 nm from a He-Ne laser. The diffraction efficiency is approximately15% for the first order. The material no requires developing process and is very easy to make. Experimental results are shown.

A new approach for fast generation of computer-generated-holograms (CGHs) by combined use of the N-LUT method and block matching motion compensation technique is proposed. Here, we apply block matching-based motion compensation algorithm to N-LUT-based CGH generation method by which a higher similarity between adjacent frames can be obtained. In the proposed method, the input video images are divided into blocks of fixed size and the CGHs of every block in reference frames are pre-calculated with the N-LUT method. The motion vectors of every block in the reference frame are extracted between reference frame and current frame, and a compensated frame image can be obtained by shifting every block’s position according to the motion vectors. Through this process, 3-D objects data to be calculated for its video holograms are dramatically reduced leading to the greater reduction of the calculation time compared with the conventional temporal redundancy-based N-LUT (TR-N-LUT) method. The experiments have found that the average number of calculated object points for one frame and the average calculation time for one object point of the proposed method are reduced by 30.05% and 21.23% respectively compared to those with the conventional TRNLUT method.

In this paper, a novel approach for fast generation of video holograms of three-dimensional (3-D) moving objects using compensated principal fringe patterns (C-PFP)-based novel-look-up-table (N-LUT) method is proposed. If the object point is changed between frames, two calculations are needed in conventional temporal redundancy-based N-LUT (TRN- LUT) method, but only one calculation is needed by compensating the difference in intensity and depth values using C-PFP. That is, hologram patterns for moving 3-D object can be calculated by simply multiplying the C-PFP to hologram pattern by difference of depth value. Experimental results with test 3-D video having camera panning reveal that the average number of calculated object points and the average calculation time for one object point of the proposed method, have found to be reduced down to 47.3%, 41.7%, and 40.5%, 32.9%, respectively compared to those of the conventional N-LUT and TR-N-LUT methods.