VACUUM-ULTRAVIOLET QUANTUM EFFICIENCY OF A PHOSPHOR-COATED CHARGE-COUPLED-DEVICE

The absolute quantum efficiency (QE) of two 1024 x 1024 pixel phosphor -coated (lumigen) charge-coupled devices has been measured in the band from 1216 to 5200 angstrom. It is found that the average QE is 17.7 /- 1.8% for the lot 1 detector and 18.1 +/- 1.8% for the lot 2 detecto r in the band from 1600 to 3800 angstrom. The sensitivity rises on the long-wavelength side of the measurement band to 32% at 5200 angstrom and falls with the wavelength below 1600 angstrom. The two detectors h ave different spatial uniformity characteristics; both have a very uni form response (+/-2%) to 5200-angstrom flat-field illumination, althou gh only one of the devices has a flat ultraviolet response. The read n oise of these devices is 8 electrons (e-).