Abstract: A digital camera optically couples a monocentric lens to image sensor arrays, without optical fibers, yet shields the image sensor arrays from stray light. In some digital cameras, baffles are disposed between an outer surface of a monocentric lens and each image sensor array to shield the image sensor arrays from stray light. In other such digital cameras, an opaque mask defines a set of apertures, one aperture per image sensor array, to limit the amount of stray light. Some digital cameras include both masks and baffles.

Abstract: A navigation method includes imaging a first celestial object with an imaging device and calibrating the pointing of the imaging device to position of the first celestial object in the image. A second celestial object and a satellite are imaged and position of the platform determined using position of the conjunction of the second celestial object and the satellite in the image of the second celestial object and satellite. Navigation systems are also described.

Abstract: A large field-of-view (FOV) imaging apparatus includes a monocentric lens, and a plurality of imaging modules comprising digital mirror device(s) (DMD) arranged to form or arranged in proximity to a spherical focal surface in optical communication with the monocentric lens such that the monocentric lens directs light rays that enter the monocentric lens at a surface of the monocentric lens towards the spherical focal surface and into the imaging modules as a function of incident angle of each light ray relative to a reference plane.

Abstract: A method of determining position of an object using an imaging device includes imaging a celestial object using an imaging device. A difference between an expected position of the celestial object and an actual position of the celestial object is determined. Pointing of the imaging device is in-flight calibrated to improve position determining by nulling the difference between the expected position of the celestial object and the actual position of the celestial object. Systems for determining position of an object relative to a vehicle are also described.

Abstract: A large field-of-view (FOV) imaging apparatus includes a monocentric lens, and a plurality of imaging modules comprising digital mirror device(s) (DMD) arranged to form or arranged in proximity to a spherical focal surface in optical communication with the monocentric lens such that the monocentric lens directs light rays that enter the monocentric lens at a surface of the monocentric lens towards the spherical focal surface and into the imaging modules as a function of incident angle of each light ray relative to a reference plane.

Abstract: A method of determining position of an object using an imaging device includes imaging a celestial object using an imaging device. A difference between an expected position of the celestial object and an actual position of the celestial object is determined. Pointing of the imaging device is in-flight calibrated to improve position determining by nulling the difference between the expected position of the celestial object and the actual position of the celestial object. Systems for determining position of an object relative to a vehicle are also described.

Abstract: A navigation method includes imaging a first celestial object with an imaging device and calibrating the pointing of the imaging device to position of the first celestial object in the image. A second celestial object and a satellite are imaged and position of the platform determined using position of the conjunction of the second celestial object and the satellite in the image of the second celestial object and satellite. Navigation systems are also described.

Abstract: A star tracker determines a location or orientation of an object, such as a space vehicle, by observing unpolarized light from one or more stars or other relatively bright navigational marks, without imaging optics, pixelated imaging sensors or associated pixel readout electronics. An angle of incidence of the light is determined by comparing signals from two or more differently polarized optical sensors. The star tracker may be fabricated on a thin substrate. Some embodiments have vertical profiles of essentially just their optical sensors. Some embodiments include micro-baffles to limit field of view of the optical sensors.

Abstract: A star camera system that includes an optical system configured to focus radiation from a star to be imaged onto a collector. Specifically, the collector is in the form of an electron bombarded active pixel sensor (EBAPS) configured to provide high gain. The EBAPS comprising a photocathode disposed in a vacuum is configured to release electron into a vacuum when exposed to radiation focused thereon by the optical system. In addition, the EBAPS includes an active pixel sensor anode disposed distant from the photocathode in the vacuum. An electric field is generated by a voltage source to direct electrons from the photocathode to the active pixel sensor anode to thereby generate an image of the star.

Abstract: Methods and apparatus ascertain a geographic position based on topographic contours of ocean surfaces. Observed ocean topographic contours are matched to predicted ocean topography and/or ocean topographic information stored in a database. Such systems and methods do not necessarily require INS, GPS, RF beacons, optical beacons or celestial sightings. These systems and methods may be used as references to correct INS. These systems and methods may be used to ascertain a geographic location of an aircraft, spacecraft, watercraft, landcraft (vehicle), person or the like. Similarly, these systems and methods may be used as part of a guidance system for guiding a craft to a destination. These systems and methods may be used in tandem with, or as backups for, other types of navigation or guidance systems or as one input to a navigation filter.

Abstract: A star camera system that includes an optical system configured to focus radiation from a star to be imaged onto a collector that is in the form of an electron bombarded active pixel sensor (EBAPS) configured to provide high gain. The EBAPS comprising a photocathode disposed in a vacuum is configured to release electrons into the vacuum when exposed to radiation focused thereon by the optical system. The EBAPS includes an active pixel sensor anode disposed distant from the photocathode in the vacuum. An electric field is generated by a voltage source to direct the electrons from the photocathode to the active pixel sensor anode. Furthermore, the collector is mounted on a translation device configured to move the collector relative to the optical system by a predetermined amount of less than pixel size in the focal plane of the optical system to increase image resolution of a plurality of images.

Abstract: A digital camera optically couples a monocentric lens to image sensor arrays, without optical fibers, yet shields the image sensor arrays from stray light. In some digital cameras, baffles are disposed between an outer surface of a monocentric lens and each image sensor array to shield the image sensor arrays from stray light. In other such digital cameras, an opaque mask defines a set of apertures, one aperture per image sensor array, to limit the amount of stray light. Some digital cameras include both masks and baffles.

Abstract: A star tracker determines a location or orientation of an object, such as a space vehicle, by observing unpolarized light from one or more stars or other relatively bright navigational marks, without imaging optics, pixelated imaging sensors or associated pixel readout electronics. An angle of incidence of the light is determined by comparing signals from two or more differently polarized optical sensors. The star tracker may be fabricated on a thin substrate. Some embodiments have vertical profiles of essentially just their optical sensors. Some embodiments include micro-baffles to limit field of view of the optical sensors.

Abstract: Methods and apparatus ascertain a geographic position based on topographic contours of ocean surfaces. Observed ocean topographic contours are matched to predicted ocean topography and/or ocean topographic information stored in a database. Such systems and methods do not necessarily require INS, GPS, RF beacons, optical beacons or celestial sightings. These systems and methods may be used as references to correct INS. These systems and methods may be used to ascertain a geographic location of an aircraft, spacecraft, watercraft, landcraft (vehicle), person or the like. Similarly, these systems and methods may be used as part of a guidance system for guiding a craft to a destination. These systems and methods may be used in tandem with, or as backups for, other types of navigation or guidance systems or as one input to a navigation filter.

Abstract: A star camera system that includes an optical system configured to focus radiation from a star to be imaged onto a collector. Specifically, the collector is in the form of an electron bombarded active pixel sensor (EBAPS) configured to provide high gain. The EBAPS comprising a photocathode disposed in a vacuum is configured to release electron into a vacuum when exposed to radiation focused thereon by the optical system. In addition, the EBAPS includes an active pixel sensor anode disposed distant from the photocathode in the vacuum. An electric field is generated by a voltage source to direct electrons from the photocathode to the active pixel sensor anode to thereby generate an image of the star.

Abstract: A star camera system that includes an optical system configured to focus radiation from a star to be imaged onto a collector that is in the form of an electron bombarded active pixel sensor (EBAPS) configured to provide high gain. The EBAPS comprising a photocathode disposed in a vacuum is configured to release electrons into the vacuum when exposed to radiation focused thereon by the optical system. The EBAPS includes an active pixel sensor anode disposed distant from the photocathode in the vacuum. An electric field is generated by a voltage source to direct the electrons from the photocathode to the active pixel sensor anode. Furthermore, the collector is mounted on a translation device configured to move the collector relative to the optical system by a predetermined amount of less than pixel size in the focal plane of the optical system to increase image resolution of a plurality of images.