Camera for the Large Scale of the Solar Surface Francis Beigbeder, Sylvain Rondi, Nadège Meunier, Michel Rieutord Thierry Roudier, Guy Delaigue, Laurent Pares, René Dorignac. Observatoire Midi-Pyrénées, Laboratoire d’Astrophysique Scientific Detectors Workshop 2005 Taormina, Italy

CALAS is an instrument whose purpose is to observe a large field of view with a very large resolution and a good temporal cadence. The main objective is the study of super-granulation. It will be installed at the Lunette Jean Rösch (a 50 cm diameter refractor) at the Pic du Midi Observatory. The instrument will present two optical paths in parallel, one for simple imaging and the second with a magneto-optical-filter (MOF) for magneto-graphic observations.

16 Mpixel CMOS Image Sensor It has a pixel size of 12 x 12 µm2, and on chip Double Sampling correction circuitry to remove the Fixed Pattern Noise caused by non-uniformities in threshold voltages of the readout electronics. The sensor is read out of through four parallel analog ouputs, 4 x 10 MHz 2,5 frame/second 3950 x 4090 pixels QE x FF40% Full Well 240 ke Noise35 e 6480:1 (76 dB) DETECTOR Fillfactory IBIS16000

To handle the CMOS sensors we have kept the timing board of a classical ARC GenII controller, but associated with customized analog, clock and interface boards. This special architecture allows us to link in parallel (LVDS) the ADCs outputs to the Acquisition System. The DSP code allows to read the detector with global or curtain shutter and windowing. CONTROLLER

The acquisition System is build with a PC under Windows XP equipped with a CORECO X64-LVDS PCI-X frame grabber, a 64 bit image acquisition board for parallel output, digital cameras. It allows image transfer to host memory at 528 MB/s Used here with four 14 bits taps configuration. We plan to have a Network Attached Storage (NAS) of several Tera Bytes capacity to save a run of 2 or 3 days of observation. ACQUISITION SYSTEM