CSPAD (Cornell–SLAC Pixel Array Detector)

CSPAD (in CXI)

The first detector specifically developed for use at LCLS is the Cornell–SLAC Pixel Array Detector (CSPAD). This detector is the result of a collaboration between Cornell University and SLAC National Accelerator Laboratory.

The CSPAD 140K, 560K, and 2.3M are used for both soft and hard X-ray applications. In instances where the detector needs to cover a large cross sectional area, the CSPAD 2.3M, with its large active sensor area, may be extremely useful. For further expansion of the active area beyond that provided by the 2.3M, multiple CSPADs can be install and read in-sync to cover a large cross section that cannot be covered by a single detector.

CSPAD camera at CXI

Figure 1. CSPAD 2.3 megapixel camera at the CXI instrument.

CSPAD: Camera Specs

  • Total length (tubings, connectors included): 14.5 in (36.8 cm)
  • Weight: 2.4 lb (1.09 kg)
  • Room temperature operation: (nominal range: 5-30 °C)
  • # of Pixels: 140K, 560K, and 2.3M pixels
  • Modules active area: (4 x 4 cm2)
  • Quantum efficiency vs. energy range: See figure

CSPAD Characteristics and Measured Performance

​CSPAD ​High Gain ​Low Gain
​Pixel per ASIC ​194 x 185 ​
​Pixel size (μm) ​110
​Noise r.m.s. (eV) ​1000 ​3500
​Max signal (8 keV 
photons equivalent)
​350 ​2700
​Frame rate (Hz) ​120 ​
​Sensor thickness (μm) ​500 ​

Download CSPAD spec sheet

CSPAD Resources

Analysis Tools for the CSPAD Detectors