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

Abstract From the Canadian patent

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 …