Abstract:
An all-reflective imaging spectrometer (10) has a three-mirror anastigmat (12) acting as its objective and a reflective triplet (14) with a dispersive element (18) providing the spectrometer collimator and imager. The system is capable of imaging an object being viewed to provide a plurality of different wavelength images of that object.
Abstract:
The present optical system provides an all-reflective boresight transfer system. A reflective mechanism receives and reflects energy from an incoming collimated beam to focus it upon a target surface. The target surface absorbs and subsequently re-emits as a longer wavelength most of the energy and also reflects a small portion of the energy such that an exit beam comprised of both the re-emitted and reflected energy is reflected through the reflecting mechanism and re-collimated by the reflecting mechanism. The exit beam has the same direction as the input beam except that it is deviated by 180.degree. and laterally offset from the input beam so that the exit beam may be used as a reference for determining or aligning the line of sight of other optical systems.
Abstract:
The present optical system provides an all-reflective continuous zoom optical system. An imaging mechanism including the tertiary mirror (14) of a three-mirror (10, 12, 14) anastigmat is moved to effect a change in the focal length, field of view, or both of the system.
Abstract:
An integrated optic holographic spectrometer (10) for analyzing electromagnetic radiation from a source (12) is disclosed. The holographic spectrometer (10) comprises a substrate (18) having aperture (20) for restricting the receipt of electromagnetic radiation. The spectrometer (10) also includes two optical waveguides (22, 24) for dividing the electromagnetic radiation received through the aperture (20) into at least a first and second portions. A geodesic lens (26) is provided for collimating the first and second portions of the electromagnetic radiation. Finally, the spectrometer (10) includes a linear detector array (28) optically communicating with the geodesic lens (26) to provide an output responsive to the interference between the first and second portions of the electromagnetic radiation received through the aperture (20).
Abstract:
A multi-channel imaging spectrometer and method of use thereof. One example of the multi-channel imaging spectrometer includes a single entrance slit, a double pass reflective triplet and at least a pair of diffraction gratings. The spectrometer is configured to receive and collimate an input beam from the entrance slit, to split the collimated beam into two spectral sub-bands using a beamsplitter, and to direct each sub-band to one of the pair of diffraction gratings. The diffraction gratings are each configured to disperse the received portion of the collimated beam into its constituent colors, and redirect the dispersed outputs through the reflective triplet to be imaged into an image sensor located at a focal plane aligned with the entrance slit.
Abstract:
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.
Abstract:
A spectrometer comprises a detector array and a prism. The prism comprises a first prism element comprising a substantially crystalline crown material, and a second prism element contacting the first prism element, the second prism element comprising a substantially crystalline flint material. The spectrometer further includes optics configured to direct light at least twice through the prism. The prism is configured to disperse light received from the optics at an incident angle therethrough into constituent spectra in visible and infrared wavelength bands that are dispersed from the prism at angles offset from the incident angle. The constituent spectra are directed onto the detector array with approximately equal dispersion across the visible and infrared wavelength bands. Among other things, desirable material selections for the first and second prism elements are also disclosed.
Abstract:
A spectrometer comprises a detector array and a prism. The prism comprises a first prism element comprising a substantially crystalline crown material, and a second prism element contacting the first prism element, the second prism element comprising a substantially crystalline flint material. The spectrometer further includes optics configured to direct light at least twice through the prism. The prism is configured to disperse light received from the optics at an incident angle therethrough into constituent spectra in visible and infrared wavelength bands that are dispersed from the prism at angles offset from the incident angle. The constituent spectra are directed onto the detector array with approximately equal dispersion across the visible and infrared wavelength bands. Among other things, desirable material selections for the first and second prism elements are also disclosed.
Abstract:
An infrared imaging optical system for focusing infrared radiation on an infrared detector, including: a front lens group having a negative optical power to receive infrared radiation and including a first front lens and a second front lens each with at least one aspherical surface; an intermediate lens group that receives the infrared radiation from the front lens group and includes a first intermediate lens, a second intermediate lens, and a third intermediate lens each with at least one aspherical surface; and a rear lens group having positive optical power, wherein the rear lens group receives the infrared radiation from the intermediate lens group and includes a first rear lens and a second rear lens each with at least one aspherical surface, and a third rear lens, wherein the imaging optical system has a stop between the rear lens group and a focal plane at said infrared detector.
Abstract:
An optical system including a first lens group configured to correct for lateral chromatic aberration, and an adjacent second lens group configured to correct for axial chromatic aberration. The optical system includes a detector disposed behind the second lens group, a mechanism for switching the optical system between a narrow field of view configuration and a wide field of view configuration, and a ray path steering system including a pair of counter-rotating grisms disposed in front of the first lens group. The optical system also includes a stabilization system configured to suppress image jitter and including a mechanism for decentering at least one lens in the first or second lens groups orthogonal to an optical axis of the optical system. A pupil of the optical system is located external to the first and second lens groups for location of a cold shield within a cryo-vac Dewar enclosing the detector.