As an appetizer...
The Bragg's law : The Reference Law to calculate the 2d spacing of the crystal according to your need of a wavelength(es) range.
Planck-Einstein equation: To convert the energy (keV) into its wavelength (A°).
Our optics work from a choice of 2d spacing cut from Germanium, Silicon or Quartz crystals.
Single crystal silicon, germanium, quartz ingots
Single crystal Quartz
Single crystal Silicon ingots

Si, Ge and Quartz ingots

Crystal selection
AlpyX has selected Germanium, Silicon and Quartz recognized for the utmost quality of their crystal lattice, their high resistance to the X-ray flux, their mechanical properties for their shapping, as they totally fit with the wavelength range of other conventionnal crystals. 
Alpyx - Crystal selection
Any other crystals (h,k,l) on request.

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