Taking a look at the calibration of a CCD detector with a fiber-optic taper
Citation
Alkire, R. W., Rotella, F. J., Duke, N. E. C., Otwinowski, Z., & Borek, D. (2016). Taking a look at the calibration of a CCD detector with a fiber-optic taper. Journal of Synchrotron Radiation, 23(2), 438–446.
Keywords
- CCD detectors
- fiber-optic tapers
- flat-field calibration
- data scaling
- anomalous signa
Brief
A series of tests were conducted on an Area Detector Systems Corporation Quantum 210r detector to examine its performance and calibration characteristics, ultimately revealing that while a partial flat-field test showed a consistent, uniform response across the module being tested, the variability of the point-spread function within the detector impacted performance.
Summary
This 2016 article in the Journal of Synchrotron Radiation, authored by R. W. Alkire, F. J. Rotella, N. E. C. Duke, Zbyszek Otwinowski, and Dominika Borek, investigates the calibration and performance of a CCD detector with a fiber-optic taper. The authors found that while the detector demonstrated uniform response consistent with manufacturer calibration in a flat-field test, experiments using a silicon single crystal diffraction peak showed significant intensity fall-off as measurements moved from the module's center to its corner.
Key Findings:
- Intensity Fall-Off: A substantial intensity decrease of up to 30% was observed as measurements shifted from the center to the corner of the detector module.
- Point-Spread Function Variability: This intensity loss is attributed to variations in the point-spread function across the detector, primarily caused by bending in the fiber-optic taper.
- Flat-Field Calibration Limitations: Standard flat-field calibration methods are inadequate for addressing these point-spread function variations.
- Software Correction: Data processing software like Scalepack can correct for this intensity loss by comparing symmetrically equivalent reflections and modeling the observed variability.
The article highlights the limitations of traditional calibration methods for CCD detectors with fiber-optic tapers and underscores the crucial role of software correction in achieving accurate intensity measurements.
Origin: https://europepmc.org/backend/ptpmcrender.fcgi?accid=PMC4815871&blobtype=pdf