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- Engström, David, 1976, et al.
(författare)
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Grid-free 3D multiple spot generation with an efficient single-plane FFT-based algorithm
- 2009
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Ingår i: Optics Express. - 1094-4087. ; 17:12, s. 9989-10000
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 2. |
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| 3. |
- Engström, David, 1976, et al.
(författare)
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Rapid SLM Design for Grid-Free Multispot Positioning in 2D and 3D with a Modified Gerchberg-Saxton Algorithm
- 2009
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Ingår i: Digital Holography and Three-Dimensional Imaging, OSA Technical Digest (CD). - Washington, D.C. : OSA. - 2162-2701. - 9781557528711 ; , s. DWB13-
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Konferensbidrag (refereegranskat)abstract
- A single-plane FFT-based algorithm which optimizes a defocused field corresponding to a desired spatial configuration of focused spots is presented. The defocused target field allows for grid-free spot positioning in 2D and 3D.
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| 4. |
- Persson, Martin, 1979, et al.
(författare)
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Computer Generated Holograms Designed to Reduce Intensity Fluctuations During SLM Update
- 2009
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Ingår i: Digital Holography and Three-Dimensional Imaging, OSA Technical Digest (CD). - Washington, D.C. : OSA. - 2162-2701. ; , s. DWC3-
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Konferensbidrag (refereegranskat)abstract
- We have investigated design criteria for calculation of computer generated holograms, aiming to reduce the deterioration of the spot pattern during SLM updates. A modified Gerchberg-Saxton algorithm that efficiently minimizes unwanted intensity fluctuations is introduced.
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| 5. |
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| 6. |
- Persson, Martin, 1979, et al.
(författare)
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Minimizing intensity fluctuations in dynamic holographic optical tweezers by restricted phase change
- 2010
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Ingår i: Optics Express. - 1094-4087. ; 18:11, s. 11250-11263
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Tidskriftsartikel (refereegranskat)abstract
- We present a method for reducing intensity fluctuations that typically occur when a spatial light modulator is updated between consecutive computer generated holograms. The method is applicable to most iterative hologram generating algorithms and minimizes the average phase difference between consecutive holograms. Applications with high stability requirements, such as optical force measurement with holographic optical tweezers, should benefit from this improvement. (C) 2010 Optical Society of America
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