Array of tapered semiconductor waveguides in a fiber for infrared image transfer and magnification

The proof-of-concept of an infrared imaging tip by an array of infrared waveguides tapered as small as 2 μm is demonstrated. The fabrication is based on a high-pressure chemical fluid deposition technique to deposit precisely defined periodic arrays of Ge and Si waveguides within a microstructured optical fiber template made of silica to demonstrate the proposed concept at wavelengths of 10.64 µm and 1.55 µm, respectively. The essential features of the imaging system such as isolation between adjacent pixels, magnification, optical throughput, and image transfer characteristics are investigated. Near-field scanning at 3.39 μm wavelength using a single tapered Ge core is also demonstrated.