Optic device comprising a plurality of resonant cavities of different lengths associated with different wavelengths

摘要

The device comprises several resonant cavities of different lengths, in order to emit over several different wavelengths, depending on the length of the corresponding cavity. Each resonant cavity comprises a convex cap, preferably hemispherical, of transparent material for the emitted wavelengths. The convex cap defines, at one end of the cavity, an excessive thickness, of length li, which enables to vary the length of the corresponding cavity. The caps are, preferably, obtained by remelting cakes of preset dimensions, for example of selenium, on the material forming the cavities.