RT Journal Article
T1 Shack-Hartmann centroid detection method based on high dynamic range imaging and normalization techniques
A1 Quiroga Mellado, Juan Antonio
A1 Vargas Balbuena, Javier
A1 González Fernández, Luis M.
A1 Belenguer Dávila, Tomás
AB In the optical quality measuring process of an optical system, including diamond-turning components, the use of a laser light source can produce an undesirable speckle effect in a Shack-Hartmann (SH) CCD sensor. This speckle noise can deteriorate the precision and accuracy of the wavefront sensor measurement. Here we present a SH centroid detection method founded on computer-based techniques and capable of measurement in the presence of strong speckle noise. The method extends the dynamic range imaging capabilities of the SH sensor through the use of a set of different CCD integration times. The resultant extended range spot map is normalized to accurately obtain the spot centroids. The proposed method has been applied to measure the optical quality of the main optical system (MOS) of the mid-infrared instrument telescope smulator. The wavefront at the exit of this optical system is affected by speckle noise when it is illuminated by a laser source and by air turbulence because it has a long back focal length (3017 mm). Using the proposed technique, the MOS wavefront error was measured and satisfactory results were obtained.
PB The Optical Society of America
SN 0003-6935
YR 2010
FD 2010-05-01
LK https://hdl.handle.net/20.500.14352/43969
UL https://hdl.handle.net/20.500.14352/43969
LA eng
NO © 2010 Optical Society of America.We thank the Ministerio de Ciencia e Innovación of Spain for the financial support of this work given by project “Contribución española al instrumento MIRI del JWST: desarrollo del simulador criogénico del telescopio” with reference ESP2004-01049.
NO Ministerio de Ciencia e Innovación of Spain
DS Docta Complutense
RD 6 abr 2025