Bibcode
Rodríguez Ramos, L. F.; Piqueras Meseguer, J. J.; Martin Hernando, Y.; Oscoz, A.; Rebolo, R.
Referencia bibliográfica
Ground-based and Airborne Instrumentation for Astronomy II. Edited by McLean, Ian S.; Casali, Mark M. Proceedings of the SPIE, Volume 7014, pp. 701449-701449-9 (2008).
Fecha de publicación:
8
2008
Número de citas
0
Número de citas referidas
0
Descripción
Lucky imaging techniques implemented by the FastCam group (see
http://www.iac.es/proyecto/fastcam/) at the Instituto de Astrofisica de
Canarias have demonstrated its ability to obtain spectacular diffraction
limited images in telescopes ranging from 1 to 4.2 m in visible
wavelengths (mainly in the I band), at the expense of using only a small
percentage of the available images. This work presents the development
of a real-time processor, FPGA-based, capable of performing all the
required processing involved in the lucky imaging technique: Bias and
flat-field correction, quality evaluation of images, quality threshold
for image selection, image recentering and accumulation, and finally
sending through Gigabit Ethernet both raw and processed images to a PC
computer. Furthermore, a real time display is generated directly from
FPGA showing both types of images, plus a histogram of the computed
quality values and the threshold used. All processes can co-exist
physically located in separated places inside the FPGA, using its
natural parallel approach, and can easily handle the 512x512 pixels at
30 fps found at the sensor camera output (an Andor Ixon+ DU-897ECSO
EMCCD). Flexibility and parallel processing features of the
reconfigurable logic have been used to implement a novel imaging
strategy for segmented-mirror telescopes, allowing separate evaluation
of every segment and posterior accumulation to achieve the resolution
limit of a single segment with the integration capability of the full
primary mirror.