Collimation and focusing properties of a planar waveguide with hyperbolic secant refractive index profile: light deflector and collimator design

Light transmission through an inhomogeneous waveguide whose refractive index profile can be represented by one-dimensional hyperbolic secant function is analysed from a geometrical optics point of view. Focusing and collimation conditions are obtained and the design of a light deflector is proposed. The possibility of obtaining almost perfect collimation for an off-axis point source by polishing the exit face of the waveguide is considered.