Dispersion design in gradient index elements using ternary blends.

We show that a gradient-index element designed from a blend of three materials allows a designer to specify independently the element's refractive index and its change in refractive index with respect to wavelength. We show further the effectiveness of this approach by comparing modeled chromatic performance of deflectors consisting of a single material, a binary blend of materials, and a ternary blend.

Ultrafast Z-scan measurements of nonlinear optical constants of window materials at 772, 1030, and 1550 nm.

Femtosecond Z-scan measurements have been performed on six window materials at 772, 1030, and 1550 nm. Measurements of the nonlinear refractive index are presented for reference materials, fused silica and BK7 and four near-infrared window materials, multispectral ZnS (CLEARTRAN), aluminum oxynitride (AlON), spinel (MgAl2O4) ceramic, and barium gallogermanate (BGG) glass.

Chromatic analysis and design of a first-order radial GRIN lens.

From the expression for optical power of a radial first-order graded-index (GRIN) lens with curved surfaces, we derive an expression for chromatic aberration. Our expressions for optical power and chromatic aberration are valid under the paraxial approximation. By applying a series of further simplifying assumptions, namely a thin lens and thin GRIN, we derive a set of equations with which one can design an achromatic GRIN lens.

Spatially-resolved Rayleigh scattering for analysis of vector mode propagation in few-mode fibers.

We use high-resolution imaging of Rayleigh scattered light through the side of few-mode optical fibers to measure the local spatial structure of propagating vector fields. We demonstrate the technique by imaging both pure modes and superpositions of modes in the LP01 and LP11 families. Direct imaging not only gives high-resolution beat length measurements, but also records the local propagation dynamics including those due to perturbations.

Rapid complex mode decomposition of vector beams by common path interferometry.

We have used common path interferometry for rapid determination of the electric field and complex modal content of vector beams, which have spatially-varying polarization. We combine a reference beam with a signal beam prior to a polarization beam splitter for stable interferograms that preserve intermodal phase shifts even in noisy environments. Interferometric decomposition into optical modes (IDIOM) provides a direct, sensitive measure of the complete electric field, enabling rapid modal decomposition and is ideally suited to single-frequency laser sources.

Achromatic GRIN singlet lens design.

Gradient refractive index (GRIN) materials are attractive candidates for improved optical design, especially in compact systems. For GRIN lenses cut from spherically symmetric GRIN material, we derive an analogue of the "lens maker's" equation. Using this equation, we predict and demonstrate via ray tracing that an achromatic singlet lens can be designed, where the chromatic properties of the GRIN counterbalance those of the lens shape.

A bio-inspired polymeric gradient refractive index (GRIN) human eye lens.

A synthetic polymeric lens was designed and fabricated based on a bio-inspired, "Age=5" human eye lens design by utilizing a nanolayered polymer film-based technique. The internal refractive index distribution of an anterior and posterior GRIN lens were characterized and confirmed against design by µATR-FTIR. 3D surface topography of the fabricated aspheric anterior and posterior lenses was measured by placido-cone topography and exhibited confirmation of the desired aspheric surface shape.