Application of the differential method to diffraction gratings that utilize total internal reflection facets

• Main Author: Smith, Michael Sean Dyck
• Language: en_US
• Published: 2007
• Online Access: http://hdl.handle.net/1993/1496

Integrated optical grating devices with facets designed to take advantage of total internal reflection have recently been demonstrated. To date, analysis of these total internal reflection (TIR) gratings has been limited to an elementary ray optics approach. This thesis presents the first analysis of these gratings based on the full electromagnetic theory of light. The validity of designing diffraction gratings with total internal reflection facets is demonstrated. Results indicate that the efficiency of the retro-reflected order of 20$\rm\sp{th}$ order gratings etched in silica glass is enhanced by more than 11 dB for the TE mode when the TIR grating design is used in place of a similar echelle grating without facet metalization. Comparisons are made between results found using the full electromagnetic theory of light and simple scalar wave approximations, qualitative agreement is found for the retro-reflected order, particularly for grating orders 15-25.