Dünnschichtspektrometer mit Transmissionsgitter

摘要

The invention relates to a spectrometer, comprising a thin light guide layer in a layered structure produced using thin-film technology between two cover layers having a lower refractive index, a light guide layer end face which has a grid and is irradiated through the light guide layer with light to be analysed, and a line-scanning sensor on which the spectrum is displayed. The stair-like stepped grid is configured as having transparent step surfaces and step edges perpendicular to the layer plane and a second medium is adjacent to the step surfaces of the grid whose refractive index is smaller than that of the light guide layer. The invention is characterized in that the grid continuously changes the height and width of its steps in the direction of the stairs in such a way that for two selected wavelengths the total light paths travelling through the light guide layer and the second medium as far as a focal point assigned to the corresponding wavelength for all adjoining front surfaces of the grid have a difference in length which is equal to the same multiple of said wavelength.