The structure and principle of double-channel elliptical crystal spectrometer are presented. The whole process of manufacturing dispersive element with natural Muscovite is specified.

With this new dispersive relationship and solution, the trapped state of photon-atom of single two-level atom in photonic crystal is discussed.

The synchrotron-based energy-dispersive X-ray diffraction method has great advantage and potential for diagnosing the crystal structure of tiny minerals and mineral inclusions.