Nonlinear scanning to optimize sector scan electro-optic reconnaissance system performance

A method for optimizing long range, sector scan panoramic electro-optical reconnaissance of a scene from an airborne craft comprising the steps of:

• (1) determining a camera scan rate and a focal plane array read rate for a desired level of operational performance;
• (2) determining a non-linear scan velocity if said scan rate is above a threshold level;
• (3) scanning the camera across the scene at said non-linear scan velocity determined in step (2);
• (4) focusing an image of the scene scanned in said step (3) onto a focal plane array and converting the image into an electronic signal that represents the scene;
• (5) processing said electronic signal to generate a digital image of the scene, wherein said processing comprises a step of correcting a pixel aspect ratio of said digital image to remove effects of said non-linear scan velocity.

A system for performing long range, sector scan panoramic electro-optical reconnaissance of a scene from an airborne craft, the reconnaissance performed at increased scan velocities for a given ground resolved distance, and forward overlap, comprising:

• first means for detecting an image of a portion of the scene and converting said image into a digital image data signal, wherein said digital image data signal is a digital representation of said image;
• second means, coupled to said first means, for focusing said portion of the scene onto said first means, and for scanning said portion of the scene across the entire scene at a non-linear scan velocity;
• and
• third means, coupled to said first means, for processing said digital image data signal to provide a visual image data signal representing a corrected image, said corrected image having a pixel aspect ratio corrected to remove the effects of said non-linear scan velocity.