The major advantage of CCDs over other detectors is their high efficiency. The wavelength response for the types of CCD currently in use on La Palma is shown in Figure . The best (thinned) devices have a peak efficiency of about 80 per cent, whilst the unthinned ones have a peak efficiency of about 50 per cent.
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Figure: Responsive
Quantum Efficiency (RQE) as a function of wavelength for the
Tektronix and EEV CCD detectors most commonly used on the La Palma Telescopes