Open AccessGrid-free 3D multiple spot generation with an efficient single-plane FFT-based algorithm
Author(s) -
David Freeman Engstrom,
Anders Frank,
Jan Backsten,
Mattias Goksör,
Jörgen Bengtsson
Publication year - 2009
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.17.009989
Subject(s) - fast fourier transform , computer science , spatial light modulator , holography , algorithm , optics , projection (relational algebra) , sample (material) , grid , field (mathematics) , mathematics , chemistry , physics , geometry , chromatography , pure mathematics
Algorithms based on the fast Fourier transform (FFT) for the design of spot-generating computer generated holograms (CGHs) typically only make use of a few sample positions in the propagated field. We have developed a new design method that much better utilizes the information-carrying capacity of the sampled propagated field. In this way design tasks which are difficult to accomplish with conventional FFT-based design methods, such as spot positioning at non-sample positions and/or spot positioning in 3D, are solved as easily as any standard design task using a conventional method. The new design method is based on a projection optimization, similar to that in the commonly used Gerchberg-Saxton algorithm, and the vastly improved design freedom comes at virtually no extra computational cost compared to the conventional design. Several different design tasks were demonstrated experimentally with a liquid crystal spatial light modulator, showing highly accurate creation of the desired field distributions.