Multistep ion exchange processes of gradient refractive index rod lens.

A mathematical model for research on the refractive index profile (RIP) of multistep ion exchange processes (IEPs) of gradient refractive index rod lenses (GRINs) is established by the different initial condition and boundary condition, based on the Fickian diffusion equation. GRIN rod lenses have been fabricated using the three-step IEPs. Research results indicate that the experimental deviations of refractive index (DRI) are in good agreement with the theoretical data.

Nondestructive measurement of refractive index profile of gradient refractive index rod lens.

In this paper, a simple nondestructive method is described to obtain the refractive index profile of a gradient refractive index rod lens by means of optical coherence tomography. The approach exploits the fact that optical coherence tomography provides a direct measurement of the optical path of the light traveled through a gradient refractive index rod lens. The refractive index profile for a gradient refractive index rod lens is retrieved by iterative fitting of the optical path calculated by the ray tracing method with that experimentally measured using optical coherence tomography.

Gradient refractive index square lenses. II. Imaging.

We establish theoretically the relationship between the lateral magnification m and the object distance L(0) for a gradient refractive index (GRIN) square lens and a GRIN rod lens. Through the linear fit of the object distance and the reciprocal of the magnification for different image locations, we use the imaging method to measure the central refractive index n(0) and focusing constant alpha of the GRIN square lens and the GRIN rod lens. The center refractive indices and focusing constant alpha of the GRIN square lens and the GRIN rod lens are 1.