Fiber optic interface for optical probes with enhanced photonic

Abstract

Fiber optic interfaces that can readily reject the collection of stray light while efficiently collecting desired light that has interacted with the subject media. These fiber optic interfaces may be incorporated into optical probes and probe tips for enhanced photonic efficiency, light manipulation, and stray light rejection. These probes are particularly well suited for use in instrumentation including spectral analysis and the light-scattering branches of spectroscopy. Specifically, the optical probes exhibit benefits for spectral analyses including those referred to as Raman, fluorescence, Rayleigh, luminescence, and diffuse reflectance. A typical probe includes a center emitter fiber surrounded by collection fibers. These fibers are arranged into a bundle and positioned behind a window. The end faces of the emitter fiber and the collection fibers are shaped to form an optical interface with desired optical characteristics. The outer and inner faces of the window may also be shaped to enhance the desired characteristics of the optical interface. In one configuration, the window's outer face is formed into a convex face so that specular reflections arising from the window's outer face are directed back toward the emitter. In another configuration, the fiber assembly is encapsulated in a low refractive index window. The window's inner face is in intimate contact with the fiber end face. In this configuration, the low refractive index encapsulent facilitates light manipulation while providing protection, isolation, and other benefits.