Abstract: A hinge assembly for a deployable mirror includes a base, a mirror segment base coupled to the base, a mirror segment coupled to the mirror segment base by two bearings, and at least one linear actuator secured to the base and capable of adjusting the mirror segment. Other embodiments of the hinge assembly are further disclosed.

Abstract: Reflective optical telescopes and method of observing a scene. One example of a reflective optical telescope includes a primary mirror positioned along a linear axis extending between an entrance aperture and an image plane, configured to receive optical radiation via the entrance aperture, a secondary mirror positioned along the linear axis and configured to receive the optical radiation from the primary mirror and to reflect the optical radiation in a direction of the primary mirror, wherein the optical radiation received by the primary mirror is unobscured by the secondary mirror, a tertiary mirror positioned along the linear axis and configured to receive the optical radiation from the secondary mirror and reflect the optical radiation in a direction of the primary mirror, and a quaternary mirror positioned along the linear axis, configured to receive the optical radiation from the tertiary mirror and reflect the optical radiation to the image plane.

Abstract: Reflective optical telescopes and method of observing a scene. One example of a reflective optical telescope includes a primary mirror positioned along a linear axis extending between an entrance aperture and an image plane, configured to receive optical radiation via the entrance aperture, a secondary mirror positioned along the linear axis and configured to receive the optical radiation from the primary mirror and to reflect the optical radiation in a direction of the primary mirror, wherein the optical radiation received by the primary mirror is unobscured by the secondary mirror, a tertiary mirror positioned along the linear axis and configured to receive the optical radiation from the secondary mirror and reflect the optical radiation in a direction of the primary mirror, and a quaternary mirror positioned along the linear axis, configured to receive the optical radiation from the tertiary mirror and reflect the optical radiation to the image plane.

Abstract: A dual-function optical system including a secondary optical path incorporated, off-axis, within a primary optical path of the system and sharing a single aperture and at least some of the optical components with the primary optical path. In one example, an optical system includes an optical telescope including a plurality of mirrors configured to receive and direct first light rays through an entrance aperture of the optical system along a primary optical path, a detector positioned behind the optical telescope in the primary optical path and configured to receive the first light rays from the optical telescope, and an illuminator positioned behind the optical telescope and configured to produce second light rays and to direct the second light rays to the optical telescope, the optical telescope being further configured to transmit the second light rays along a secondary optical path through the entrance aperture of the optical system.

Abstract: According to various aspects, an optical zoom lens system and a method magnifying an image using an optical zoom lens system are disclosed. In one example, the optical zoom lens system comprises a first lens group including a first focus-tunable lens and a first negative lens, a second lens group, positioned after the first lens group in an optical path, a third lens group, positioned after the second lens group in the optical path, and a fourth lens group, positioned after the third lens group in the optical path, including a second focus-tunable lens and a second negative lens.

Abstract: A hinge assembly for a deployable minor includes a base, a mirror segment base coupled to the base, a minor segment coupled to the minor segment base by two bearings, and at least one linear actuator secured to the base and capable of adjusting the mirror segment. Other embodiments of the hinge assembly are further disclosed.

Abstract: A dual-function optical system including a secondary optical path incorporated, off-axis, within a primary optical path of the system and sharing a single aperture and at least some of the optical components with the primary optical path. In one example, an optical system includes an optical telescope including a plurality of mirrors configured to receive and direct first light rays through an entrance aperture of the optical system along a primary optical path, a detector positioned behind the optical telescope in the primary optical path and configured to receive the first light rays from the optical telescope, and an illuminator positioned behind the optical telescope and configured to produce second light rays and to direct the second light rays to the optical telescope, the optical telescope being further configured to transmit the second light rays along a secondary optical path through the entrance aperture of the optical system.

Abstract: According to various aspects, an optical zoom lens system and a method magnifying an image using an optical zoom lens system are disclosed. In one example, the optical zoom lens system comprises a first lens group including a first focus-tunable lens and a first negative lens, a second lens group, positioned after the first lens group in an optical path, a third lens group, positioned after the second lens group in the optical path, and a fourth lens group, positioned after the third lens group in the optical path, including a second focus-tunable lens and a second negative lens.

Abstract: A hinge assembly for a deployable mirror includes a base, a mirror segment base coupled to the base, a mirror segment coupled to the mirror segment base by two bearings, and at least one linear actuator secured to the base and capable of adjusting the mirror segment. Other embodiments of the hinge assembly are further disclosed.

Abstract: A microporous graphite foam, comprising a matrix of graphite fibers joined by a graphitized graphite-forming precursor, wherein the foam comprises irregular interstitial spaces having an average pore size in the range from about 0.1 to about 10 microns and a void fraction in the range from about 80% to about 95%. A process for producing a microporous graphite foam including a matrix of graphite fibers joined by a graphitized graphite-forming precursor. In its various embodiments, the graphite foam has one or more of pore sizes less than about ten microns, low bulk density, high physical strength and good machinability, while also having the desirable characteristics of graphite, including high thermal conductivity, electrical conductivity and solderability. A cryogenic cooling system including the graphite foam. In one embodiment, the graphite foam is a component of a cooling interface in the cryogenic cooling system.

Abstract: A microporous graphite foam, comprising a matrix of graphite fibers joined by a graphitized graphite-forming precursor, wherein the foam comprises irregular interstitial spaces having an average pore size in the range from about 0.1 to about 10 microns and a void fraction in the range from about 80% to about 95%. A process for producing a microporous graphite foam including a matrix of graphite fibers joined by a graphitized graphite-forming precursor. In its various embodiments, the graphite foam has one or more of pore sizes less than about ten microns, low bulk density, high physical strength and good machinability, while also having the desirable characteristics of graphite, including high thermal conductivity, electrical conductivity and solderability. A cryogenic cooling system including the graphite foam. In one embodiment, the graphite foam is a component of a cooling interface in the cryogenic cooling system.

Abstract: A process for producing a microporous graphite foam including a matrix of graphite fibers joined by a graphitized graphite-forming precursor. In one embodiment, the process includes providing a plurality of graphite fibers; mixing the graphite fibers with a graphite-forming precursor; compressing the mixture; forming a precursor matrix comprising the graphite fiber and the graphite-forming precursor; first heating the matrix to a temperature at which the graphite-forming precursor is carbonized, forming a carbonized matrix; and second heating the carbonized matrix to a temperature at which the carbonized graphite-forming precursor is graphitized, forming the microporous graphite foam. The graphite foam has one or more of pore sizes less than about ten microns, low bulk density, high physical strength and good machinability, while also having the desirable characteristics of graphite, including high thermal conductivity, electrical conductivity and solderability.

Abstract: An adjustable optical mounting includes a mounting support or frame, and multiple adjusters to provide a six-degree-of-freedom adjustment of the support relative to a base. The adjusters include cams with cam surfaces that bear against and engage slots in the support or frame, to translate the support in directions parallel to the base. In addition, threaded devices and resilient (compliant) devices such as springs are utilized to adjust the height of the support relative to the base, at multiple locations. The cams and the threaded devices of the adjusters may be independently adjusted to translate the support relative to the base, and/or to change the height and/or tilt angle of the support.