Spatially-variant photonic crystals (SVPCs), in which the orientation of the unit cell changes as a function of position, are shown to be capable of abruptly controlling light beams using just low index materials and can be made to have high polarization selectivity. Multi-photon direct laser writing in the photo-polymer SU-8 was used to fabricate three-dimensional SVPCs that direct the flow of...

In this paper we continue the study of the edge intersection graphs of single bend paths on a rectangular grid (i.e., the edge intersection graphs where each vertex is represented by one of the following shapes: x, p, y, q). These graphs, called B1-EPG graphs, were first introduced by Golumbic et al (2009) [5]. We consider the natural subclasses of B1-EPG formed by the subsets of the four singl...

C ouplers (or power divider/combiners) with outputs that differ in phase by 90 degrees are an important part of RF/microwave design. This tutorial provides an overview of various types of 90-degree combiners, using both lumped element and transmission line structures. Our intention is to introduce the subject to engineers who may be unfamiliar with these couplers, and perhaps offer some reminde...

We proposed and designed novel arrayed-waveguide gratings (AWGs) for time-to-space (T-S) conversion-based high-speed optical signal processing. Recently, the frequency selectivity of AWGs has been considerably improved, offering the possibility of powerful tool for the manipulation of optical spectra. An arrayed-waveguide grating was fabricated, integrated with a 90 degree deflecting mirror. Mo...