Optical Properties of Diamond Films

The optical properties of diamond films have been studied quite extensively, too. In the spectral range from about 220 to 1000 nm pure diamond does not show any absorption at aU. This transparency renders it an attractive material for spectroscopic appUcations Uke as windows or lens systems in spectrometers. 

The luminescence characteristics of diamond films are also strongly affected by the presence of defects. Although it requires considerable energies, an excitation across the entire bandgap is possible. It may be effected by (laser) light, by an 

Furthermore, there are broad bands that can each be assigned to a range of transitions. Particularly worth mentioning among them are the so-called blue band A at ca. 435 nm (-2.85 eV) that arises from dislocations, and the green band A at about 563 nm ( 2.2eV) presumably originating from boron doping. 

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