title: Quantitative analysis and temperature-induced variations of moiré pattern in fiber-coupled imaging sensors.
abstract: Imaging fiber bundles can map the curved image surface formed by some high-performance lenses onto flat focal plane detectors. The relative alignment between the focal plane array pixels and the quasi-periodic fiber-bundle cores can impose an undesirable space variant moiré pattern, but this effect may be greatly reduced by flat-field calibration, provided that the local responsivity is known. Here we demonstrate a stable metric for spatial analysis of the moiré pattern strength, and use it to quantify the effect of relative sensor and fiber-bundle pitch, and that of the Bayer color filter. We measure the thermal dependence of the moiré pattern, and the achievable improvement by flat-field calibration at different operating temperatures. We show that a flat-field calibration image at a desired operating temperature can be generated using linear interpolation between white images at several fixed temperatures, comparing the final image quality with an experimentally acquired image at the same temperature.
authors.forename: Salman
authors.initials: S
authors.lastname: Karbasi
authors.forename: Ashkan
authors.initials: A
authors.lastname: Arianpour
authors.forename: Nojan
authors.initials: N
authors.lastname: Motamedi
authors.forename: William M
authors.initials: WM
authors.lastname: Mellette
authors.forename: Joseph E
authors.initials: JE
authors.lastname: Ford