Optical waveguide grating

Several techniques can be employed to couple an optical beam propagating in free space into a thin-film optical waveguide. Grating coupling and prism coupling (Fig. 15.4) are briefly outlined here, since these methods are applied in actual reverse waveguide and MCLW configurations, respectively. 

Optical Biosensors Surface Plasmon Resonance and Optical Waveguide Grating... 

Butler, T. M. Igata, E. Sheard, S. J. Blackie, N., Integrated optical Bragg grating based chemical sensor on a curved input edge waveguide structure, Opt. Lett. 1999, 24, 525 527... 

H. Berends, DBR grating spectral filters for optical waveguide sensors, PhD thesis, (University of Twente, The Netherlands, 1997). 

Figure 4. Techniques for coupling an external radiation field into optical waveguides (a) prism coupling, (b) grating coupling, and (c) end-fire coupling.

Peroxide Sensitizers. Poly(methylmethacrylate), PMMA, is the first polymer reported to exhibit an increase in refractive index upon irradiation with uv light (41). Irradiation at either 325 nm (Cd laser) or 365 nm (Hg arc) was found to give an index increase of up to 0.3%, and the resolution, determined from gratings, was shown to be at least 5000 lines/mm. Applications to optical waveguides and holographic elements were suggested. This phenomenon was a serendipitous discovery. The PMMA had been intended for use as an inert matrix for reversible photodimerization when its own photosensitivity was uncovered. 

Lukosz W, Clerc D, Nellen PM, Stamm C, Weiss P (1991) Output grating couplers on planar optical waveguides as direct immunosensors. Biosens Bioelectron 6 227-232... 

Fig. 7 Optical waveguide-coupling methods, (a) end-firing focused beam and end-firing optical fiber (b) prism coupling (c) grating coupling...

An electro-active integrated optical waveguide (EA-lOW) with a separation of 8 mm between the input and output grating couplers was used to experimentally assess the sensitivity of EA-lOW-based measurements on surface-confined films. Measurements performed on adsorbed MB (e = 7,800 M cm at 633 nm) at a... 

Keywords Microarray DNA microarray Carbohydrate microarray Protein microarray Antibody microarray G protein-coupled receptor microarray Cellular microarray Optical biosensor Resonant waveguide grating biosensor Surface plasmon resonance Dynamic mass redistribution... 

Wawro D, Tibuleac S, Magnusson R, Liu H (2000) Optical fiber endface biosensor based on resonances in dielectric waveguide gratings. Proc SPIE 39 86... 

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