A NEW CONCEPT MINIATURE CHARGE-COUPLED-DEVICE CAMERA FOR VACUUM-ULTRAVIOLET AND SOFT X-RAYS SPECTROSCOPY

A very compact, vacuum compatible charge coupled device (CCD) camera h as been developed for vacuum ultraviolet and soft x-ray imaging spectr oscopy. It can house any CCD frame format and two of them have been se lected: 385 x 576 pixels, suitable for normal incidence spectroscopy ( 300-2500 Angstrom), and 256 x 1024 pixels, for grazing incidence appli cations (5-300 Angstrom). Owing to its small and lightweight package, it can be placed at the focus of vacuum spectrometers. A new concept c ooling system is based on a three stage thermoelectric cooler in therm al connection with the CCD through a 30-cm-long flexible conductor, al lowing the detector to have stress-free movements along the focal plan e and a constant temperature. The camera head has been designed to ach ieve a high cooling efficiency, thus the CCD can be operated at -40 de grees C. This detector is well suited for applications that require hi gh sensitivity and signal to noise ratio, wide dynamic range, good spa tial and spectral resolutions. In addition, it overcomes the limits of fixed detectors and lets the optical performances of the spectrometer remain unchanged. The CCD camera has been tested during an experiment of laser produced plasma spectroscopy and some preliminary results ar e reported. (C) 1998 American Institute of Physics.