Interactive computation of holograms using a look-up table

Abstract

Several methods of increasing the speed and simplicity of the computation of off-axis transmission holograms are presented, with applications to the real-time display ofholographic images. The bipolar intensity approach allows for the real-valued linear summation of interference fringes, a factor of 2 speed increase, and the elimination of image noise caused by object self-interference. An order of magnitude speed increase is obtained through the use of a precomputed look-up table containing a large array of elemental interference patterns corresponding to point source contributions from each of the possible locations in image space. Results achieved using a data-parallelsupercomputer to compute horizontal-parallaxonly holographic patterns containing six megasamples indicate that an image comprised of 10,000 points with arbitrary brightness (gray scale) can be computed in under 1 s. Implemented on a common workstation, the look-up table approach increases computation speed by a factor of 43.

A New Architecture of High-Performance Digital Hologram Generator based on Independent Calculation of a Holographic Pixel

“…Imaging Group(지금은 Object-based Media Group)은 고속 CGH를 위한 연구를 가장 먼저 시작한 연구그룹이다 [4] . 여 기서는 HPO(horizontal-parallax-only) 방식의 CGH 기법을 이용해 디지털 홀로그램을 생성하는 연구를 수행하였다.…”

Recent progress in computer-generated holography for three-dimensional scenes

“…Therefore, by pre-calculating the optical fields for every distance and storing them, the LUTs can be constructed. The hologram of a 3D object can be obtained simply by adding the LUTs that are shifted according to the lateral position and multiplied with the complex amplitude of the 3D object points, as shown in Figure 3(a) [21,22]. In the case of a moving 3D scene, the temporal redundancy can also be considered to reduce the computational load.…”

Reconstruction of Computer Generated Holograms by Spatial Light Modulators

“…The generation of CGH is computationally expensive, therefore a number of algorithms have been employed to exploit redundancy and reduce computation time [6]. Lucente et al utilised a bipolar intensity method, described herein, to reduce the computation time of CGH generation [7]. Ito et al further applied this method to reconstruction of CGH holograms onto liquid crystal on silicon (LCoS) spatial light modulators [8,9].…”