DOI: 10.17863/cam.121345
title: Research data supporting "Fourier-plane wavefront and SLM aberration characterization via iterative scanning of beam deflector segments"

description: The dataset contains the experimental research data collected for the “Fourier-plane wavefront and SLM aberration characterization via iterative scanning of beam deflector segments” research paper. The purpose of the experiment was to measure incident wavefront (phase and amplitude) and to include this data in hologram generation to reduce aberrations and improve quality of the reconstructed images. The holograms were generated using the Gerchberg-Saxton algorithm. The holograms were displayed on the Santec SLM-200 spatial light modulator, and the images were captured by Zelux CS165MU CMOS camera in a focal plane of the projection (Fourier) lens of 6cm focal length. The code to generate the data is available on GitHub: https://github.com/antoni-wojcik/hololab_wavecorr. The experiment was repeated in three configurations: 1. CMOS sensor placed in the focal plane of the lens: “f6cm_exact” subdirectories. 2. CMOS sensor displaced from the focal plane by a few mm: “f6cm_large_offset_inwards” subdirectories. 3. CMOS sensor placed in the location where the images generated with wavefront correction data from Santec (the SLM manufacturer) appear in focus: “santec_correction_dist” subdirectories. This dataset is divided into two directories, each containing the three subdirectory types (for each experiment) listed above: 1. Wavefront measurement (“wavefront_measurement” directory): This contains data collected when measuring the incident wavefront. This includes “log.txt” which is the log information outputted by the program to check if the operation was successful; “tile_gradients.npy” are the raw measured gradients at each tile; “segment_gradients.png” is the visualisation of the gradients; “phase_wavefront.npy” and “amp_wavefront.npy” are the computed phase and amplitude of the wavefront (the latter is computed from “amp_wavefront_raw_intensity.npy” raw intensity data); “phase_wav.png” and “amp_wav.png” are the visualisations of these. The directories contain also “roi_reference” files which show the location of the reference point used in calculating the gradients and “roi##” subdirectories containing more files of the same type showing how the location of points from selected patches shift as the program optimises the gradients. In these subdirectories “#.txt” files contain specific information about the location and gradients for each of the spots. 2. Image correction (“wavefront_measurement” directory): This contains data collected when generating and projecting the holograms. This includes “info.txt” explaining the configurations tested in the experiment; “log.txt” which is the log information outputted by the program to check if the operation was successful; “holo_#” (holograms) and “capture_#” data (images), where # corresponds to the different configurations. Additionally, “target” data (image), “target_proj” data which is the target image corrected from a projection distortion; “aft_matrix”, which is the affine transform matrix data to transform the captured images to compare them to the target pattern; and “santec_backplane_correction” which is the wavefront correction data (grayscale values) provided by Santec.