| Popis: |
Grating coupling is the waveguide access technology which in principle allows for the integration of the access function together with the integrated optical processing functions on a monolithic planar substrate. The fundamental merit of grating coupling technology is its geometrical and, to a large extent, its technological compatibility with the planar processes which define the integrated signal processing waveguide circuit. However, poor coupling efficiency, highly dispersive character, absence of user friendly modelling tools, fabrication difficulties have long prevented this technology from being implemented into practical sensor and microsystem designs. Most of these difficulties are being overcome and grating couplers are envisaged as part of commercial system applications. This contribution will review the points where recent technological progress are decisive, illustrate for the future users some attractive features of waveguide coupling gratings and also underline for the designer some of the traps that may be encountered. |
