Optical imaging system including generally conical, transparent protective dome and optically refractive fixed corrector for reversing conical deformation created by viewing through the dome

摘要

A camera (40) is mounted on a gimbal (44) inside a missile (30) and views forwardly through a transparent, generally conical front dome or ogive (70). An optically refractive corrector (72) is mounted in front of the camera lens (42) for integral movement therewith. The corrector (72) has a least one conical surface segment (74a,74b) which is dimensioned to reverse optical conical deformation created by the dome (70). The conical deformation includes little or no refractive power in a plane defined by the axis (38) of the dome (70) and the look axis (46) of the camera (40) and gimbal (44), and progressively varying one-dimensional refraction perpendicular to this plane. Variables including the apex angles ( alpha 1, alpha 2) of cones (76,78) which define the surfaces (74a,74b), the angle ( alpha 3) between the axes (76b,78b) of the cones (76,78), the distances (D1,D2) between the apices (76a,78a) of the cones (76,78) and the center (74c) of the corrector (72), the tilt angle ( alpha 5) and the index of refraction of the corrector (72) provide sufficient degrees of freedom to enable a best fit solution which substantially reverses the conical deformation created by the dome (70). IMAGE