Abstract-We present a vector modal solution for the evanescent coupler comprising an optical fiber and a slab waveguide. We identify the normal vector ridge modes of the device for different configurations. The dispersion characteristics and the power transmission properties of these modes are presented. Also, the effect of the proximity between the waveguides on the ridge modes is investigated.

In this study, channel waveguides fabricated in photopolymer films by direct-writing using a low-power CW laser, are used as phase objects in a simple plane-wave diffraction setup, and the refractive index modulation profiles of the waveguides are characterized using the recorded diffraction patterns. Index profiles are modeled by piece-wisely combining two Gaussian functions representing the central and the tail regions. Measured diffraction patterns are matched with patterns generated using the model. This simple model makes it possible to design various channel waveguides embedded into polymer substrates. The proposed model is tested on three distinctive waveguide profiles written on the same Acrylamide/Polyvinyl Alcohol based photopolymer with different exposures.

Abstract-A new resonance breaking in-fiber switch as an all-optical network component is investigated and presented. A transient grating is applied to break the transverse resonance of the fundamental waveguide mode and the power coupled into the higher order propagating mode is computed using coupled mode theory (CMT). The coupling of the modes with the grating forming beams in the evanescent region of the waveguide is investigated with four wave mixing (FWM). High conversion efficiency is calculated in the case of perfect phase matching at communication wavelength 1550 nm. The conversion efficiency of the proposed structure is considered in terms of third-order nonlinear susceptibility, and the effect of design and tuning parameters are investigated for grating forming geometry and laser beam intensity, respectively.

In this paper, image-based regulation control of a robot manipulator with an uncalibrated vision system is discussed. To compensate for the unknown camera calibration parameters, a novel prediction error formulation is presented. To achieve the control objectives, a Lyapunov-based adaptive control strategy is employed. The control development for the camera-in-hand problem is presented in detail and a fixed-camera problem is included as an extension.

An all-optical pulse controlled switch/modulator based on evanescent coupling between a polymer slab waveguide and a single mode fiber is demonstrated. Very fast all-optical modulation/switching is achieved via Kerr effect of the nonlinear polymer placed in the evanescent region of the optical fiber. Local refractive index perturbation (Δn=-1.45612×10(-5)) on the thin film leads to 0.374 nW power modulation at the fiber output, which results in a switching efficiency of ≈1.5%.