The conditions of existence and propagation for light in so-called photonic crystals are controlled by the periodic structuring of dielectric materials.
Here, on the one hand, the propagation of light for specific spectral ranges is completely suppressed, important for e.g. realizing color filters, while on the other hand the dispersion and diffraction properties are controlled using these structures. This is possible all the way to the non-diffractive propagation of light rays for specific directions in crystal.
These innovative photonic materials possess diverse application potential and require precisely controlled structuring in the sub-wavelength range. As a result, electron beam lithography is preferably used to produce photonic crystals in various dielectric materials.