Patent ID: 7586678

Claim:
An optical imaging system for obtaining a multi-field-of-view image of an observation area from a wide field-of-view image and a narrow field-of-view image thereof, said system comprising: a wide field-of-view and a narrow field-of-view Cassegrain-type objectives for respectively forming said wide field-of-view and narrow field-of-view images, each of said objectives comprising a primary mirror defining a concave optical surface and a secondary mirror disposed coaxially with said primary mirror and defining a convex optical surface, said wide field-of-view objective being positioned coaxially to said narrow field-of-view objective rearwardly of the secondary mirror thereof and non-obstructively to light entering said narrow field-of-view objective, the secondary mirror of said narrow field-of-view objective being provided with a light passage extending therethrough at an apex thereof; focussing means for focussing and superposing both of said wide field-of-view and narrow field-of-view images at a same focal plane; a focal plane array generally disposed at said focal plane for detecting said superposed wide field-of-view and narrow field-of-view images, thereby obtaining said multi-field-of-view image.