Synchrotron Optics
4C-SR-V2 (Four Crystal Monochromator)
The Xradia 4C-SR-V2 Four Crystal Monochromator delivers monochromatic or white light from an x-ray source such as a synchrotron.
The Xradia 4C-SR-V2 is useful for techniques such as x-ray micro diffraction where it is used in conjunction with our Kirkpatrick-Baez focusing system (described above). In micro x-ray diffraction, the randomly orientated micro sample is first identified by its white light Laue diffraction pattern, followed by illumination with known monochromatic light for determination of 'd' spacing.
The four crystal monochromator is operated in the configuration as shown below. This arrangement has the property of directing the monochromatic x-rays along the same axis as the incoming white light. The Monochromator crystals used are two identical channel-cut crystals mounted so they rotate in opposite directions when scanning photon energy. When set to a Bragg angle of zero, white light is passed. Wavelength adjustment is made by moving a linear slide that drives two counter-rotating high precision bearings. The crystal Bragg angle is measured to one arc second accuracy by an optical rotary encoder.
4C-SR-V2 (Four Crystal Monochromator) Specifications
Bragg angular range |
7º to 70º |
Energy range for silicon (111) |
16222 to 2103 eV (lower energy range determined by window and air absorption. |
Channel cut separation |
4.00 mm matched for both crystals |
Window thickness |
100 micron (for both 'in' and 'out' window) |
Beam size section |
2 x 2 mm |