Line–plane-switching infrared bundle for push-broom sensing fiber imaging

•Line–plane-switching infrared fiber bundle with high-resolution was reported.•Chalcogenide fibers employed possess cladding of 50 μm and error of 1% in diameter.•The fiber bundle format is 64 × 9 to implement 192 × 3 format linear array imaging.•Wide-field IR push-broom image employed fiber bundle was successfully demonstrated.

We reported line–plane-switching infrared (IR) fiber bundle with high-resolution of 0.027 μm−1, small numerical aperture (NA) of 0.20 (±0.02), high filling-factor, and bending radius of around 5.0 mm, i.e. extremely good flexibility. This fiber bundle is made from chalcogenide glass fibers, possessing core (As40S58Se2) of 45 μm, cladding (As40S60) of 50 μm, and error of 1% in diameter. Based on the lens used to demonstrate IR push-broom imaging, the format of matching fiber bundle we chose is 64 × 9 in system to implement 192 × 3 format linear array imaging. By principle-demonstrating system incorporated this fiber bundle coupled with small scale Infrared Focal Plane Array (IRFPA), wide-field and long-array IR push-broom image was successfully demonstrated.