PANORAMIC OPTICAL POWER AMPLIFIER IN Yb-DOPED MULTI-CORE PHOSPHATE-BASED OPTICAL FIBER

This project focuses on the development of compact, high electrical plug-in efficiency, and high gain panoramic optical amplifiers suitable for image amplification. Laser tracking and pointing of remote targets for space/air surveillance and control applications require a suitable image amplifier covering a wide field of view to improve signal to noise in image detection, leading to longer target range capability and/or stronger immunity to atmospheric disturbance. Our approach centers on a new phosphate glass and fiber technology that enables much higher ytterbium doping than previously possible - resulting in high gain per unit length and short fiber lengths (~10 cm). NP Photonics pre-form and fiber drawing technology makes possible the fabrication of two-dimensional arrays of doped cores embedded in a pump cladding layer -where each core represents a pixel in the image amplifier. Our preliminary calculations with 9 to 19 active cores arranged in a two-dimensional pattern indicate that it is possible for each pixel to have high gain (>20 dB) and large acceptance angle (>10 degrees), and for the amplifier to have high electrical efficiency (>40%) when pumped with commercially available 975nm multimode diodes.