Optical device for correcting geostationary satellite imagery for earth curvature effects

摘要

An optical adapter for an imaging system correcting images of spherical or near spherical bodies such as the earth during satellite image collection. An imaging system includes an image collector that collects a two-dimensional image of the body from a distance above the body such as from a satellite in geostationary orbit. The collected image is disk shaped and includes distortion due to earth curvature, primarily in the form of a loss of resolution due to the foreshortening of earth features in a radial direction extending outward from the center of the image disk. The optical adapter receives the collected image, transforms the collected image to correct the distortion, and outputs a corrected image with essentially uniform spatial resolution across the areas for which the correction is applied. An image sensor such as charge-coupled device array senses the corrected image and creates a digital representation of the corrected image.