Position sensitive detectors (PSD) have been around for many years and their successful application to X-ray diffraction experiments has been well documented. Early PSD detector designs are based on fragile wire anode technology, problematic due to the fact that they are easily damaged by over exposure to X-rays and are often microphonic. To overcome these problems, we have pioneered a new technology in which the fragile wire anode has been replaced by an indestructible alloy "knife edge " blade anode which is non microphonic, does not suffer from over exposure to the X-ray beam and is very rugged. 

Inel curved position sensitive detectors enable diffraction experiments to be made on powders, solids and liquids in real time.

The detectors are curved about a segment of a circle allowing the user to select a detector that provides optimum resolution for each and every experiment including XRD, SAXS, WAXS, etc. When used as part of an X-ray  experiment Equinox  detectors will measure the entire diffraction pattern simultaneously.

Inel curved PSD detectors

The detectors have no moving parts and eliminate the need for mechanical scanning devices such as complex scanning goniometers used in conventional diffraction instruments. They do not require routine maintenance.

 







                                Principle of a CPS detector                                                   Principle of conventional point detector
                    Real-Time simultaneous data acquisition                                       Step-wise time-dependent acquisition

Description (linear and curved position sensitive detector)
Equinox PSD detectors are either a linear or curved chamber into which a solid blade anode and segmented cathode is mounted. Within the chamber there is also a cathode assembly and with the addition of argon / ethane gas, the detector can be defined as a proportional type detector.  When an X-ray photon becomes incident on the detector anode an electrical charge develops on the cathode at a position that is spatially coincident with the incident photon. This electrical charge can be measured in terms of its intensity and position about the anode / cathode by way of a delay line. This signal is digitized and then stored in an electronic card. The desired S:N is achieved by multiscan accumulation. In practice an excellent diffraction pattern can be recorded in just a few seconds and at very high resolution.
 
Resolution (linear and curved position sensitive detector)
Equinox PSD detectors are essentially spatial detectors used in such a way that they are made to directly intersect the diffracted, reflected or transmitted X-ray beam. The length or radius of the detector determines its spatial or angular position about the X-ray beam or 2 theta and the distance to the sample determines resolution. This unique design also provides an opportunity in diffraction experiments to limit the incident X-ray beam width on the sample to less than 100 microns with a conventional X-ray source and to less than 20 microns with a micro X-ray source and so provides a superb opportunity for micro diffraction experiments. To meet the needs of today's diffraction requirements we have designed detectors with differing lengths and curvatures providing a choice of resolutions from 0.04 to 0.1 degrees FWHM. There are many experiments that require linear detectors as an alternative to curved and to meet this need we have designed a range of detectors with varying anode lengths.

Applications (linear and curved position sensitive detector)