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PubMed · 11779944

High-sensitivity CCD-based X-ray detector.

Walter C Phillips·Alexander Stewart·Martin Stanton·Istvan Naday·Charles Ingersoll
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Abstract

The detector is designed for imaging measurements requiring relatively high sensitivity and high spatial resolution. The detector can discriminate single X-ray photons, yet has the wide dynamic range ( approximately 10000:1) associated with integrating detectors. A GdO2S2 phosphor screen converts the incoming X-ray image into an optical image. The optical image is coupled (without demagnification) to the CCD image sensor using a fiber optic faceplate. The CCD (Philips Semiconductors) has an area of 4.9 x 8.6 cm with 4000 x 7000 12 microm pixels. A single 12 keV X-ray photon produces a signal of 100 e-. With 2 x 2 pixel binning, the total noise per 24 microm pixel in a 100 s image is approximately 30 e- the detective quantum efficiency is >0.6 at 1 X-ray photon per pixel, and the full image can be read out in <4 s. The spatial resolution is 50 microm. The CCD readout system is fully computer-controlled, allowing flexible operation in time-resolved experiments. The detector has been characterized using visible-light images, X-ray images and time-resolved muscle diffraction measurements.

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Actin CytoskeletonAnimalsCalibrationEquipment DesignImage Processing, Computer-AssistedMuscle ContractionMuscle, SkeletalMyosinsPlant StructuresRadiometryRanidaeSoftwareTemperatureX-Ray DiffractionX-RaysJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Walter C Phillips, Alexander Stewart, Martin Stanton, Istvan Naday, Charles Ingersoll. 2001-12-24. High-sensitivity CCD-based X-ray detector.. https://doi.org/10.1107/s0909049501020143

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