Pointable optical system with coude optics having a short on-gimbal path length

摘要

A coude gimbal structure includes a two-axis gimbal system having an outer gimbal pivotable about a first rotational axis, and an inner gimbal supported on the outer gimbal and pivotable about a second rotational axis which intersects the first rotational axis at an intersection point. A folded afocal three-mirror anastigmat has a positive-optical-power primary mirror, a negative-optical-power secondary mirror, and a positive-optical-power tertiary mirror, and a first flat fold mirror, and a second flat fold mirror. A beam path incident upon the primary mirror is reflected from the primary mirror to the secondary mirror. The tertiary mirror lies on the second rotational axis, the first flat fold mirror redirects the beam path reflected from the secondary mirror to the tertiary mirror, and the second flat fold mirror lies at the intersection point and redirects the beam path reflected from the tertiary mirror along the first rotational axis.

主权项

1. A coude gimbal structure comprising:
a two-axis gimbal system including an outer gimbal pivotable about a first rotational axis, and an inner gimbal supported on the outer gimbal and pivotable about a second rotational axis which is perpendicular to the first rotational axis and which intersects the first rotational axis at an intersection point; and a reflective coude optical system including a positive-optical-power primary mirror mounted to the inner gimbal, wherein the primary mirror is directed along a third axis passing through the intersection point and lying perpendicular to the first rotational axis and perpendicular to the second rotational axis, and an intersection flat fold mirror at the intersection point, wherein the positive optical power primary mirror has a primary mirror aperture diameter, and wherein a coude path length of the reflective coude optical system is about ½ of the aperture diameter of the primary mirror.