{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:40:38Z","timestamp":1760244038236,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2009,12,24]],"date-time":"2009-12-24T00:00:00Z","timestamp":1261612800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper we show a fast, specialized hardware implementation of the wavefront phase recovery algorithm using the CAFADIS camera. The CAFADIS camera is a new plenoptic sensor patented by the Universidad de La Laguna (Canary Islands, Spain): international patent PCT\/ES2007\/000046 (WIPO publication number WO\/2007\/082975). It can simultaneously measure the wavefront phase and the distance to the light source in a real-time process. The pipeline algorithm is implemented using Field Programmable Gate Arrays (FPGA). These devices present architecture capable of handling the sensor output stream using a massively parallel approach and they are efficient enough to resolve several Adaptive Optics (AO) problems in Extremely Large Telescopes (ELTs) in terms of processing time requirements. The FPGA implementation of the wavefront phase recovery algorithm using the CAFADIS camera is based on the very fast computation of two dimensional fast Fourier Transforms (FFTs). Thus we have carried out a comparison between our very novel FPGA 2D-FFTa and other implementations.<\/jats:p>","DOI":"10.3390\/s100100001","type":"journal-article","created":{"date-parts":[[2009,12,25]],"date-time":"2009-12-25T04:53:37Z","timestamp":1261716817000},"page":"1-15","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["An Efficient Pipeline Wavefront Phase Recovery for the CAFADIS Camera for Extremely Large Telescopes"],"prefix":"10.3390","volume":"10","author":[{"given":"Eduardo","family":"Magdaleno","sequence":"first","affiliation":[{"name":"Departmento de F\u00edsica Fundamental y Experimental, Electr\u00f3nica y Sistemas, University of La Laguna, Avd. Francisco Sanchez s\/n, 38203 La Laguna, Spain"}]},{"given":"Manuel","family":"Rodr\u00edguez","sequence":"additional","affiliation":[{"name":"Departmento de F\u00edsica Fundamental y Experimental, Electr\u00f3nica y Sistemas, University of La Laguna, Avd. Francisco Sanchez s\/n, 38203 La Laguna, Spain"}]},{"given":"Jos\u00e9 Manuel","family":"Rodr\u00edguez-Ramos","sequence":"additional","affiliation":[{"name":"Departmento de F\u00edsica Fundamental y Experimental, Electr\u00f3nica y Sistemas, University of La Laguna, Avd. Francisco Sanchez s\/n, 38203 La Laguna, Spain"}]}],"member":"1968","published-online":{"date-parts":[[2009,12,24]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2100","DOI":"10.1364\/JOSAA.19.002100","article-title":"Fast wave-front reconstruction in large adaptive optics systems with use of the Fourier transforms","volume":"19","author":"Poyneer","year":"2002","journal-title":"J. Opt. Soc. Am. A"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1325","DOI":"10.1364\/AO.30.001325","article-title":"Wavefront reconstruction using iterative Fourier transforms","volume":"30","author":"Roddier","year":"1991","journal-title":"Appl. Opt"},{"key":"ref_3","first-page":"123","article-title":"Modal Fourier wavefront reconstruction using graphics processing units","volume":"16","author":"Rosa","year":"2007","journal-title":"J. Electron. Imaging"},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Rodr\u00edguez-Ramos, J.M., Femen\u00eda, B., Montilla, I., Rodr\u00edguez-Ramos, L.F., Marichal-Hern\u00e1ndez, J.G., L\u00fcke, J.P., L\u00f3pez, R., and Mart\u00edn, Y. (2009, January June). The CAFADIS camera: a new tomographic wavefront sensor for adaptive optics. Paris, France.","DOI":"10.1051\/ao4elt\/201005011"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1364\/JOSAA.22.000117","article-title":"Wave-front sensing from subdivision of the focal plane with a lenslet array","volume":"22","author":"Clare","year":"2005","journal-title":"J. Opt. Soc. Am. A"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"701539","DOI":"10.1117\/12.789312","article-title":"2D-FFT implementation on FPGA for wavefront phase recovery from the CAFADIS camera","volume":"7015","author":"Magdaleno","year":"2008","journal-title":"Proc. SPIE"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1402","DOI":"10.1016\/j.sigpro.2006.12.004","article-title":"Novel design of multiplier-less FFT processors","volume":"87","author":"Zhou","year":"2007","journal-title":"Signal Process"},{"key":"ref_8","unstructured":"Chang, T.S., and Jen, C.W. (, January May). 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