Improvements for determining the modulation transfer function of charge-coupled devices by the speckle method Pozo Molina, Antonio Manuel Ferrero, A. Rubiño López, Antonio Manuel Campos Acosta, Joaquín Pons, Alicia CCD Charge-coupled device Modulation transfer function Speckle imaging We present and evaluate two corrections applicable in determining the modulation transfer function (MTF) of a charge-coupled device (CCD) by the speckle method that minimize its uncertainty: one for the low frequency region and another for the high frequency region. The correction at the low-spatial-frequency region enables attenuation of the high power-spectral-density values that arise from the field and CCD response non-uniformities. In the high-spatial-frequency region the results show that the distance between the CCD and the aperture is critical and significantly influences the MTF; a variation of 1 mm in the distance can cause a root-mean-square error in the MTF higher than 10%. We propose a simple correction that minimizes the experimental error committed in positioning the CCD and that diminishes the error to 0.43%. 2014-07-18T11:42:51Z 2014-07-18T11:42:51Z 2006 info:eu-repo/semantics/article Pozo, A.M.; et al. Improvements for determining the modulation transfer function of charge-coupled devices by the speckle method. Optics Express, 14(13): 5928-5936 (2006). [http://hdl.handle.net/10481/32717] 1094-4087 http://hdl.handle.net/10481/32717 10.1364/OE.14.005928 eng info:eu-repo/semantics/openAccess Optical Society of America