Ghost imaging with a single detector

Author(s): Yaron Bromberg, Ori Katz, Yaron Silberberg

Abstract:

“We experimentally demonstrate pseudothermal ghost imaging and ghost diffraction using only a single detector. We achieve this by replacing the high-resolution detector of the reference beam with a computation of the propagating field, following a recent proposal by Shapiro [ Phys. Rev. A 78, 061802(R) (2008)]. Since only a single detector is used, this provides experimental evidence that pseudothermal ghost imaging does not rely on nonlocal quantum correlations. In addition, we show the depth-resolving capability of this ghost imaging technique.”

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Publication: Physical Review A
Issue/Year: Phys. Rev. A, Volume 79, Issue 5, 053840 (2009)
DOI: 10.1103/PhysRevA.79.053840

Microdisplays in holographic mastering applications

Author(s): Sven Plöger, Sven Krüger, Stefan Osten, Günther Wernicke

Abstract:

“We demonstrate implementation and performance of microdisplay systems based on liquid-crystal technology in a variety of applications in holographic mastering. These displays can encode 2D objects information in grey scale or address holographic patterns in amplitude or phase. The main advantage is here to address any content dynamically with typically 60 Hz. Furthermore they show a resolution up to 1920×1200 pixels with a pixel size as small as 6.4 microns. Therefore they are extremely suitable for a dynamic or multi-exposure mastering process, to incorporate image content, phase-encode objects or any holographic features. This technology is already being used in holographic security applications as well as in commercial and display holography. We report about a few applications/implementations and show experimental results and performance parameters.”

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Publication: SPIE Proceedings
Issue/Year: Proc. SPIE, Vol. 7358, 73581H (2009);
DOI: 10.1117/12.823474

Poincaré-sphere representation of phase-mostly twisted nematic liquid crystal spatial light modulators

Author(s): V Durán, P Clemente, Ll Martínez-León, V Climent, J Lancis

Abstract:

“We establish necessary conditions in order to build a phase-only wavefront modulation system from a liquid crystal display. These conditions determine the dependence of the polarization state of the light emerging from the display on the addressing gray level. The analysis, which is carried out by means of the coherence-matrix formalism, includes the depolarization properties of the device. Two different types of polarization distributions at the output of the liquid crystal cells are found. This approach is applied to a twisted nematic liquid crystal display. In this case, an optimization algorithm must be designed in order to select the input polarization state that leads to the required distributions. We show that the Poincaré-sphere representation provides a convenient framework to design the optimization algorithm as it allows for a reduced number of degrees of freedom. This feature significantly decreases the computation time. Laboratory results are presented for a liquid crystal on silicon display showing a phase modulation depth greater than 2π rad with an intensity variation lower than 6%. In addition, a hybrid ternary modulation (HTM), an operation regime employed in holographic data storage, is achieved.”

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Publication: Journal of Optics A
Issue/Year: J. Opt. A: Pure Appl. Opt. (2009), Opt. 11 085403
DOI: 10.1088/1464-4258/11/8/085403

Influence of the incident angle in the performance of Liquid Crystal on Silicon displays

Author(s): A. Lizana, N. Martín, M. Estapé, E. Fernández, I. Moreno, A. Márquez, C. Iemmi, J. Campos, and M. J. Yzuel

Abstract:

“In this paper we experimentally analyze the performance of a twisted nematic liquid crystal on silicon (LCoS) display as a function of the angle of incidence of the incoming beam. These are reflective displays that can be configured to produce amplitude or phase modulation by properly aligning external polarization elements. But we demonstrate that the incident angle plays an important role in the selection of the polarization configuration. We performed a Mueller matrix polarimetric analysis of the display that demonstrates that the recently reported depolarization effect observed in this type of displays is also dependant on the incident angle. ”

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Publication: Optics Express
Issue/Year: Optics Express, Vol. 17, Issue 10, pp. 8491-8505 (2009)
DOI: 10.1364/OE.17.008491