White beam macroscope for beamline TOMCAT in SLS

A low magnification X-ray system with a continuous magnification change in the range of 2x – 4x was delivered to beamline TOMCAT at the Swiss Light Source synchrotron, Switzerland, at the end of 2010. The system uses a fast scientific CMOS camera and custom developed optomechanics. Changing the magnification, focusing and orientation adjustment of the camera are motorized and operate within the existing beamline control system.

Low magnification white beam system for the TOMCAT beamline on the SLS synchrotron

The fast scientific CMOS camera PCO Dimax is used for various experiments within the beamline TOMCAT on the Swiss Light Source synchrotron(PSI, Switzerland). For the planned experiments it needed to be complemented with optomechanics that would meet the following parameters:

  • large numerical aperture
  • variable magnification in the range of 2x – 4x
  • motorized magnification change, arbitrary value
  • motorised rotation of the camera around the vertical axis due to the alignment of the perpendicularity of the line on the camera and the axis of rotation of the sample
  • universal scintillator holder (use of different scintillator)

The system was designed and built by Elya Solutions Ltd. The design is based on a similar system developed for the ANKA synchrotron, but a large part had to be modified due to dimensional constraints on the TOMCAT beamline and also due to the continuous change of magnification. The system finally consists of:

  • a scintillator holder on a motorized stage (stepper motor), equipped with an independent optical encoder (position readout)
  • mirror with reduced X-ray scattering and optional lead glass filter
  • lens operating at magnifications of 2x – 4x (depending on the relative position of the scintillator, lens and camera)
  • motorised camera table (z-axis, stepper motor), equipped with independent optical encoder (z-axis position reading)
  • motorised rotary table for camera (stepper motor)

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