Phase Matching Of The Diffraction Gratings

The manufacturing of large diffraction gratings is always a great task for discussion in the field of grating. And that the technique how to get the large gratings is also a very difficult thing. The overseas grating experts have to search the other ways so as to get them, because it have to face some unovercomed technique problem for setting up the large ruling machine. The appearance of the large mosaic gratings attracts all people who devote themselves to the manufacture of diffaction gratings. Some experts who come from America,Canada,Russia and Japan have been doing a lot of research about the large mosaic gratings. The technique to manufacture the large diffraction gratings have been promoted highly. Based on the former fruits.a method that manufacture the large diffraction gratings by phase matching was brought forward in this disseration.The main works shown as below:1. Retrospect the characteristic.application and development of large diffraction gratings and introduce the overseas fruits in details. Analyze two overseas typical methods of large mosaic gratings. At meantime,some advantages of the large gratings made by the mosaic method were shown out.2. The theory of the phase matching and testing were discussed in details. Some formulas were deduced firstly in this paper by using of the grating space diffraction equation and the method of coordinate transformation. The internal relationship between the diffraction phase difference and the location of the gratings was opened out. At meantime,this relationship was used to direct the virtual mosaic grating course successfully.3.The mathematical model of the mosaic grating's diffraction intensity was set up by using of the Fraunhofer Principle. The diffraction intensity was analog calculated by using of the MathcadT.O program. The calculation result show that the intensity and the spectrum resolution power increase highly.4.The experiment equipment was designed and the phase matching experiment was done too. The course of experiment was discussed and the result photos were given. The result show that this method is feasible.