Off-axis three-mirror anastigmat having corrector mirror
AssigneeRaytheon Company
InventorLacy G. Cook
Life of this patent
Estimating the term…
Abstract
A corrector mirror folds the optical path between the objective and relay portions of a three-mirror anastigmat. The corrector mirror is a non-powered mirror having a nominally flat but higher order aspheric surface. By placing the corrector mirror between the objective portion and an intermediate image formed by the objective portion, the field offset of the anastigmat can be significantly increased. A large field offset makes the off-axis anastigmat ideal for use with an on-axis dewar for infrared imaging applications.
Claims19
An infrared imaging system comprising:
- an on-axis dewar having an infrared detector;
- and
- an off-axis anastigmat for focusing infrared radiation on the detector, the anastigmat having a primary mirror, a corrector mirror, a secondary mirror and a tertiary mirror in serial arrangement along an optical path, the primary mirror forming an intermediate image that is relayed by the secondary mirror and the tertiary mirror.
An infrared imaging system comprising:
- an on-axis dewar having an infrared detector, wherein said on-axis dewar further comprises a real unobscured entrance pupil prior to said primary mirror;
- and
- an off-axis anastigmat for focusing infrared radiation on the detector, the anastigmat having a primary mirror, a corrector mirror, a secondary mirror and a tertiary mirror in serial arrangement along an optical path.
An infrared imaging system comprising:
- an on-axis dewar having an infrared detector;
- an off-axis anastigmat for focusing infrared radiation on the detector, the anastigmat having a primary mirror, a corrector mirror, a secondary mirror and a tertiary mirror in serial arrangement along an optical path;
- a final image surface that is substantially flat and located subsequent to said tertiary mirror and is optically conjugate to an intermediate image between said primary and secondary mirrors by the operation of said secondary and tertiary mirrors;
- and
- a real unobscured exit pupil positioned between said tertiary mirror and said final image surface and optically conjugate to an entrance pupil by the operation of said primary, corrector, secondary, and tertiary mirrors.
An infrared imaging system comprising:
- a dewar having an infrared detector;
- a three-mirror anastigmat for focusing infrared radiation on the detector, the anastigmat having exactly three mirrors including a primary mirror, a secondary mirror, and a tertiary mirror in serial arrangement along an optical path;
- and
- a corrector mirror positioned in the optical path between the primary mirror and the secondary mirror, the primary mirror forming an intermediate image that is relayed by the secondary mirror and the tertiary mirror.
An infrared imaging system comprising:
- a dewar having an infrared detector;
- and
- an off-axis anastigmat for focusing infrared radiation on the detector, the anastigmat having a primary mirror, a corrector mirror, a secondary mirror and a tertiary mirror in serial arrangement along an optical path, wherein at least one of the primary mirror, the secondary mirror, and the tertiary mirror has a shape selected from the group consisting of a conic section configuration and a general aspheric configuration, the primary mirror forming an intermediate image that is relayed by the secondary mirror and the tertiary mirror.
Dependencies are inferred from the claim text.