Waveguide couplers

Figure 15. (a) Index profile for one, two and three layer GRIN waveguide coupler structures and (b) corresponding coupling efficiencies. 

A. J. Sangster and H. Wang, A generalized analysis for a class of rectangular waveguide coupler employing narrow wall slots, IEEE Trans. Microw. Theory Tech., vol. 44, no. 2, pp. 283-290, Feb. 1996.doi 10.1109/22.481578... 

In SPR sensors with angular modulation, the sensor output is the coupling wavelength kt and therefore the instrumental contribution to sensor sensitivity Srii is equal to Skr/Suef. By differentiating the coupling conditions for the prism, grating, and waveguide coupler (see Chap. 1 of this volume [1]) in ef and k, we obtain ... 

In the optical system of an SPR sensor, surface plasmons are optically excited and the SPR signal is encoded into a light wave interacting with the surface plasmons. Based on the method of excitation of surface plasmons, SPR sensors can be classified as SPR sensors based on (i) prism couplers, (ii) grating couplers, and (iii) waveguide couplers (Fig. 4). 

Fig. 4 SPR sensors based on a prism couplers, b grating couplers, and c waveguide couplers...

The research in glass modification by use of short laser pulses is driven by scientific interest and their applications have been demonstrated for the formation of three dimensional optical memories and multicolour images , the direct writing of waveguides, waveguide couplers and splitters, waveguide optical amplifier, and optical gratings" ". 

Fig. 9. Periodically flat-structured grating waveguide couplers and photo-switching behaviors.

Bang,C.-U. Shishido, A. Ikeda, T. (2007). Azobenzene Liquid-Crystalline Polymer for Optical Switching of Grating Waveguide Couplers with a Flat Surface. Macromol. Rapid Commun., 2007,28,1040-1044. 

Microstrip and waveguide realizations of directional couplers are shown in Fig. 4.27(b) and Fig. 4.27(c) where the microstrip coupler couples in the backward direction and the waveguide coupler couples in the forward direction. The powers at the output ports of the hybrids shown in Fig. 4.28 and Fig. 4.29 are equal and so the hybrids serve to spHt a signal into two equal half power signals, as weU as having directional sensitivity. 

Zimba et al. [8] doped thin polymer films on quartz substrates with chromophores. By combining a waveguide coupler to a FT-Raman spectrometer, they were able to detect... 

Zhao, X.M., Smith, S.P., Waldman, S.J., Whitesides, G.M., and Prentiss, M. (1997) Demonstration of waveguide couplers fabricated using microtransfer molding. Appl. Phys. Lett., 71 (8), 1017-1019. 

Tamir T, Beam and Waveguide Couplers, Integrated Optics (Tamir T, ed.), Springer-Verlag, Berlin Chap. 3. pp. 84-119 (1975). 

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