Side-Polished Coherent Fiber Bundle Assemblies: A Pathway to Large Imaging Arrays

Current state-of-the-art coherent fiber bundles, with core densities as high as 65,000 (65 k) cores/mm
²
, are limited to a maximum number of 100 k cores. To address this limitation, this work presents a new fabrication approach for increasing the core count. This approach involves mechanically reshaping multiple existing circular bundles into hexagonal- like shapes and assembling them to form a large imaging array, with minimal dead-space ( non-imaging region). The reshaping and assembly process is only applied to one end of the fiber bundles for reducing image dead-space, while the remaining length is untouched for retaining mechanical flexibility. Through applying this process to three existing 1 m length, 100 k core count fiber bundles, a combined imaging array consisting of 254 k (
$\pm$
5%) cores over a total cross-sectional area of 3.94 mm
²
was fabricated. This core count is extremely close to the video graphics array (VGA) imaging standard consisting of 0.3 Megapixels. With this new approach, achieving flexible, high density imaging arrays with core counts approaching 1 million pixels, the high definition (HD) standard, is a real possibility in the upcoming decade.