AR architectures based on TIR waveguides require surface diffraction gratings to couple light in and out. Traditionally, the spectral response of a grating is tuned by blazing, i.e., creating faceted grooves with precise angles. However, blazed facets are difficult to achieve using resist-based techniques such as e-beam lithography. In this talk I will describe a new approach to making blazed AR grating masters by mechanical ruling, in which grooves are created by deforming a metallic surface with a diamond stylus.
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