Full parallax three-dimensional computer generated hologram with occlusion effect using ray casting technique

Author(s):

Hao Zhang, Qiaofeng Tan and Guofan Jin

Abstract:

“Holographic display is capable of reconstructing the whole optical wave field of a three-dimensional (3D) scene. It is the only one among all the 3D display techniques that can produce all the depth cues. With the development of computing technology and spatial light modulators, computer generated holograms (CGHs) can now be used to produce dynamic 3D images of synthetic objects. Computation holography becomes highly complicated and demanding when it is employed to produce real 3D images. Here we present a novel algorithm for generating a full parallax 3D CGH with occlusion effect, which is an important property of 3D perception, but has often been neglected in fully computed hologram synthesis. The ray casting technique, which is widely used in computer graphics, is introduced to handle the occlusion issue of CGH computation. Horizontally and vertically distributed rays are projected from each hologram sample to the 3D objects to obtain the complex amplitude distribution. The occlusion issue is handled by performing ray casting calculations to all the hologram samples. The proposed algorithm has no restriction on or approximation to the 3D objects, and hence it can produce reconstructed images with correct shading effect and no visible artifacts. Programmable graphics processing unit (GPU) is used to perform parallel calculation. This is made possible because each hologram sample belongs to an independent operation. To demonstrate the performance of our proposed algorithm, an optical experiment is performed to reconstruct the 3D scene by using a phase-only spatial light modulator. We can easily perceive the accommodation cue by focusing our eyes on different depths of the scene and the motion parallax cue with occlusion effect by moving our eyes around. The experiment result confirms that the CGHs produced by our algorithm can successfully reconstruct 3D images with all the depth cues.”

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Publication: Journal of Physics: Conference Series
Issue/Year: J. Phys.: Conf. Ser. 415 012048
DOI: 10.1088/1742-6596/415/1/012048

Implementation of phase-shift patterns using a holographic projection system with phase-only diffractive optical elements

Author(s): Wei-Feng Hsu, Yu-Wen Chen, and Yuan-Hong Su

Abstract:

“We proposed a method to implement spatial phase-shift patterns with subdiffraction limited features through a holographic projection system. The input device of the system displayed phase-only diffractive optical elements that were calculated using the iterative Fourier-transform algorithm with the dummy-area method. By carefully designing the target patterns to the algorithm, the diffractive optical elements generated the Fourier-transformed images containing the phase-shift patterns in which the widths of dark lines were smaller than the diffraction limit. With these demonstrations, we have successfully shown that the near-field phase-shift lithographic technique can be realized through an inexpensive maskless lithographic system and can still achieve subdiffraction limited images.”

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Publication: Applied Optics
Issue/Year: Applied Optics, Vol. 50, Issue 20, pp. 3646-3652 (2011)
DOI: 10.1364/AO.50.003646

The Applications and Technology of Phase-Only Liquid Crystal on Silicon Devices

Author(s): Collings, N.; Davey, T.; Christmas, J.; Chu, D.; Crossland, B.

Abstract:

“An introduction to the technology of liquid crystal on silicon (LCOS) devices leads on to a discussion of the application areas which have been and are being opened up by the development of phase-only devices.”

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Publication: Journal of Display Technology
Issue/Year: Journal of Display Technology, Vol. 7, Issue 3, pp. 112-119 (2010)
DOI: 10.1109/JDT.2010.2049337

Wide viewing angle holographic display with a multi-spatial light modulator array

Author(s):

Finke, Grzegorz; Kozacki, Tomasz & Kujawi{‘{n}}ska, Ma{l}gorzata

Abstract:

“In the paper we present the design of a wide viewing angle display system capable of displaying digital holograms captured in a rotary CCD configuration. We have discussed the two possible configurations of multi LC SLMs system: with a normal LC SLM illumination and with tilted LC SLMs and parallel illumination. The second system was selected and the tilted plane algorithm, necessary for recalculation of displayed holograms was tested. Finally we have presented and discussed different means of visual perception of holographic images: with an asymmetric diffuser and with an eyepiece.”

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Publication: SPIE Proceedings, Volume 7723
Issue/Year: Proc. SPIE 7723, Optics, Photonics, and Digital Technologies for Multimedia Applications, 77230A , 2010
DOI: 10.1117/12.855778

Speed-up of hologram generation using ClearSpeed Accelerator board

Author(s): Noriyuki Tanabe, Yasuyuki Ichihashi, Hirotaka Nakayama, Nobuyuki Masuda and Tomoyoshi Ito

Abstract:

“We have sped up the calculation of a computer-generated hologram by parallel computing using ClearSpeed Advance Dual CSX600 PCI-X Accelerator Board by ClearSpeed Technology plc. By using two boards in parallel, our system was able to perform the calculation 50 times as fast as a personal computer.”

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Publication: Computer Physics Communications
Issue/Year: Computer Physics Communications, Volume 180, Issue 10, October 2009, Pages 1870-1873
DOI: 10.1016/j.cpc.2009.06.001

Superhydrophobic surface structures in thermoplastic polymers by interference lithography and thermal imprinting

Author(s): Christian W.J. Berendsen, Marek Škereň, David Najdek and František Cerný

Abstract:

“We present a method to produce superhydrophobic surfaces in thermoplastic polymer substrates. The method involves the creation of a nickel stamp using a customized laser interference lithography technique and electroplating processes. This stamp is used to emboss sub-micrometer periodic structures into the thermoplastic. The modified surface is coated with a hydrophobic plasma-polymerized hexafluoropropene layer. Surfaces with different periodicity and relief depth were created. On the surface with the highest aspect ratio, advancing water contact angles of 167° were measured with a water contact angle hysteresis of below 5°.”

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Publication: Applied Surface Science
Issue/Year: Applied Surface Science, Volume 255, Issue 23, 15 September 2009, Pages 9305-9310
DOI: 10.1016/j.apsusc.2009.07.001

Color translucent head-up display based on a segmented Fourier hologram

Author(s):

Jaroslaw Suszek, Maciej Sypek, Andrzej Siemion, Agnieszka Fajst, Michal Makowski and Andrzej Kolodziejczyk

Abstract:

“The paper presents the numerical and experimental results of reconstructing images from a spatially segmented Fourier hologram with additional carrier frequencies, acting as a translucent head-up display (HUD). Successful reconstructions of colorful images visible at the infinity were achieved. The design procedure is described and some limitations of the method are discussed, like the appearance of ghost images. Exemplary results from numerical and real experiments are given. In order to obtain color images three beams of primary colors were successfully utilized to create a color mixture.”

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Publication: Photonics Letters of Poland
Issue/Year: Vol 1, No 3 (2009)
DOI: 10.4302/plp.2009.3.02

A novel three-dimensional holographic display system based on LC-R2500 spatial light modulatora

Author(s): Huadong Zheng, Yingjie Yu, Cuixia Dai

Abstract:

“A novel holographic display system is proposed in this paper. The system takes LC-R2500, a kind of reflective liquid crystal spatial light modulator, (LC-SLM) as the core display unit, which can meet the requirement of real-time reconstruction of three-dimensional (3D) objects from holograms in free space. The relationship between hologram recording and image reconstruction is discussed, and the parameters associated with the magnification of reconstructed image over original object are determined. Experimental results of holographic display using the system are also given in the end.”

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Publication: Optik – International Journal for Light and Electron Optics
Issue/Year: Optik – International Journal for Light and Electron Optics, Volume 120, Issue 9, May 2009, Pages 431-436
DOI: 10.1016/j.ijleo.2007.11.002

Phase Contrast Projection Display Using Photopolymer

Author(s): Piao, Mei-Lan; Kim, Nam; Park, Jae-Hyeung

Abstract:

“We propose a phase contrast filter using photopolymer, for the phase contrast projection display. The photopolymer has high photosensitivity such that its optically induced refractive index change has a linear dependency on the illuminating light intensity. We implemented a phase contrast projection display using photopolymer as a phase contrast filter. By controlling the refractive index change of the photopolymer, we successfully convert an input phase image into a high contrast intensity image. We also investigated the effect of the photopolymer illumination condition on the quality of the displayed intensity image. As a projector, we achieved 82% phase to intensity conversion efficiency, which implies that the proposed method can potentially have much higher light efficiency than conventional projection display.”

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Publication: Journal of the Optical Society of Korea
Issue/Year: Journal of the Optical Society of Korea, Volume 12, Issue 4, December 2008, pp.319-325
DOI: 10.3807/JOSK.2008.12.4.319

Structured illumination in total internal reflection fluorescence microscopy using a spatial light modulator

Author(s): Reto Fiolka, Markus Beck, and Andreas Stemmer

Abstract:

“In wide-field fluorescence microscopy, illuminating the specimen with evanescent standing waves increases lateral resolution more than twofold. We report a versatile setup for standing-wave illumination in total internal reflection fluorescence microscopy. An adjustable diffraction grating written on a phase-only spatial light modulator controls the illumination field. Selecting appropriate diffraction orders and displaying a sheared (tilted) diffraction grating allows one to tune the penetration depth in very fine steps. The setup achieves 91 nm lateral resolution for green emission.”

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Publication: Optics Letters
Issue/Year: Optics Letters, Vol. 33, Issue 14, pp. 1629-1631
DOI: 10.1364/OL.33.001629