General description
The surface diffractometer is equipped with a pixel detector constructed by the SLS detector group. This second-generation PILATUS II detector was installed in October 2005 (see Figure below) and uses photon-counting technology with essentially no background noise. In February 2022, we upgraded our detector to Eiger 500K.
Specifications for Eiger 500 K
| Spec. | Value |
|---|---|
| Active area | 1030 x 514 pixels |
| Pixel size | 75.0 mm x 75.0 mm |
| Field of view | 77.2*38.7 = 2961 mm2 |
| Frame rate | 3000 Hz (continous) |
| Location | 1140.8 +/- 0.25 mm from the centre of the diffractometer (gamma axis) |
| Energy range | 5 keV - 23 keV |
Mounting
The detector is mounted on the delta arm with its center nominally along the nu-rotation axis. The detector can, however, be shifted laterally both up/down and sideways using positioning screws on the detector holding bracket.
The detector flight tube has 3 extension pieces of lengths 200, 100, and 50 mm. When all three pieces are used and a compact detector 4-slit module is mounted on the front, the slit module is approximately 60 mm from the center of the diffractometer.
The flight tube length can be varied in steps of 50 mm between 725 and 1075 mm, using any combination of the three extension tubes (50, 100, and 200 mm).
Shih-Wen Huang viewed by March 2026