Large aperture CCD x-ray detector for protein crystallography using a fiberoptic taper

Large aperture CCD x-ray detector for protein crystallography using a fiberoptic taper

Citation

The full citation for the article, using the format found in the provided source excerpt, is below:

M.G. Strauss, E.M. Westbrook, I. Naday, T.A. Coleman, M.L. Westbrook, D.J. Travis, R.M. Sweet, J.W. Pflugrath and M. Stanton, "CCD-Based Detector for Protein Crystallography with Synchrotron X Rays," Nucl. Instr. and Meth., vol. A297, pp. 275-295, 1990.

Keywords

  • CD-based detector
  • Protein crystallography
  • Synchrotron X-ray
  • Fiberoptic taper
  • Image intensifier
  • Detective quantum efficiency (DQE)
  • Spatial resolution
  • Dynamic range
  • Diffraction images
  • Lysozyme crystals
  • Myosin head cryst

Brief

The article focuses on the design and performance of a CCD-based X-ray detector for protein crystallography using synchrotron X-ray sources, and does not mention fiber optic plate coupled Pb-free Perovskite X-ray cameras, low-dose-rate imaging, or dental diagnosis. The article describes a detector that converts X-rays to visible light using a phosphor screen, demagnifies the light image with a fiber optic taper, intensifies it with an image intensifier, and finally focuses it on a CCD for data acquisition. The authors report that the detector was tested at a synchrotron facility, achieving a detective quantum efficiency (DQE) of 0.36 and a dynamic range of 10,000.

Summary

Scientists developed a new x-ray detector for protein crystallography that uses a charge-coupled device (CCD). This detector was tested at the National Synchrotron Light Source (NSLS) and showed promising results in recording high-quality diffraction data from protein crystals.
How the Detector Works: The detector uses a fiberoptic taper to focus x-rays onto a CCD. This design allows for a large aperture, which is necessary for resolving closely spaced Bragg spots. The detector also incorporates an image intensifier to increase sensitivity.
Key Findings:

  • The detector achieved a detective quantum efficiency (DQE) of 0.36, meaning it could detect 36% of the incident x-ray photons.
  • It had a dynamic range of 10,000, allowing it to measure a wide range of x-ray intensities.
  • The spatial resolution was about 160 µm, which was limited by the pixel size of the CCD.
  • The detector was successfully used to collect diffraction data from crystals of chicken egg-white lysozyme and myosin.
Limitations and Future Improvements:
  • The fiberoptic taper and lens system introduced some distortion and nonuniformity in the images. Future designs could use an array of larger CCDs to reduce or eliminate the need for demagnification.
  • The researchers also identified the need to improve the light yield of the phosphor and the precision of the analog-to-digital converter (ADC).

Origin: https://www.osti.gov/servlets/purl/5992273

 

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