A holographic weapon sight with a housing that has a viewing end and an opposing target end. The viewing path is defined from the viewing end to the target end. The sight has a light source that projects a light beam along a path. The sight also has a diffractive optical element (DOE) disposed in the path of the light beam, and the DOE reconstructs an image of a reticle. The sight includes a parabolic reflector that reflects the image of the reticle. The parabolic reflector may be disposed in the viewing path such that a user views a target along the viewing path through the parabolic reflector from the viewing end.

A holographic weapon sight with a housing that has a viewing end and an opposing target end. The viewing path is defined from the viewing end to the target end. The sight has a light source that projects a light beam along a path. The sight also has a diffractive optical element (DOE) disposed in the path of the light beam, and the DOE reconstructs an image of a reticle. The sight includes a parabolic reflector that reflects the image of the reticle. The parabolic reflector may be disposed in the viewing path such that a user views a target along the viewing path through the parabolic reflector from the viewing end.

Optimal field mappings that provide the highest contrast images for back-scanned and time delay integration (TDI) imaging are given. The mapping can be implemented for back-scanned imaging with afocal optics including an anamorphic field correcting assembly configured to implement a non-rotationally symmetric field mapping between object space and image space to adjust distortion characteristics of the afocal optics to control image wander on a focal plane array. The anamorphic field correcting assembly can include one or more mirrors or lenses having non-rotationally symmetric aspherical departures. For optimal TDI imaging, anamorphic optics are also employed.

Optimal field mappings that provide the highest contrast images for back-scanned and time delay integration (TDI) imaging are given. The mapping can be implemented for back-scanned imaging with afocal optics including an anamorphic field correcting assembly configured to implement a non-rotationally symmetric field mapping between object space and image space to adjust distortion characteristics of the afocal optics to control image wander on a focal plane array. The anamorphic field correcting assembly can include one or more mirrors or lenses having non-rotationally symmetric aspherical departures. For optimal TDI imaging, anamorphic optics are also employed.

To maximize the light capturing and imaging resolution capability of an imaging satellite while minimizing weight, the primary reflector and other elements of the optical path have a shape optimized to the shape of the satellite. For a nanosatellite with a square cross-section, the first mirror and other elements of the telescope section in the optical path have a square cross-section, as does the sensor array of the camera section.

A cata-dioptric optical system for high resolution imaging in visible and infrared bands. The system includes a concave primary mirror, a convex secondary mirror, at least one beam splitter, a first folding mirror, a first group of lenses, a second group of lenses, and at least two image planes. The image planes have one or more aggregated sensors, where a first image plane receives rays from the first group of lenses and a second image plane receives rays from the second group of lenses, and at least one image plane is positioned behind the primary mirror and at a radial distance from the optical axis that is no more than the radius of the primary mirror.

In some embodiments, optical systems with a reflector and a lens proximate a light output opening of the reflector provide light output with high spatial uniformity and high efficiency. The reflectors are shaped to provide substantially angularly uniform light output and the lens is configured to transform this angularly uniform light output into spatially uniform light output. The light output may be directed into a light modulator, which modulates the light to project an image.

In one embodiment, an optical system includes: a first lens configured to receive incoming light from an object; a first mirror comprising a central aperture, the first mirror configured to refract the light from the first lens, reflect the light, and refract the light reflected from the first mirror; a second mirror configured to receive the light from the first mirror, wherein the light is refracted towards a first surface of the second mirror where the light is reflected back and refracted upon exiting the second mirror; a negative corrector lens configured to refract the light from the second mirror through the central aperture of the first mirror; and a positive corrector lens configured to receive the light through the central aperture of the first mirror and refract the light to an imaging surface.

In one embodiment, an optical system includes: a first lens configured to receive incoming light from an object; a first mirror comprising a central aperture, the first mirror configured to refract the light from the first lens, reflect the light, and refract the light reflected from the first mirror; a second mirror configured to receive the light from the first mirror, wherein the light is refracted towards a first surface of the second mirror where the light is reflected back and refracted upon exiting the second mirror; a negative corrector lens configured to refract the light from the second mirror through the central aperture of the first mirror; and a positive corrector lens configured to receive the light through the central aperture of the first mirror and refract the light to an imaging surface.

An automatic astronomical observation system includes an astronomical telescope (1), a star finding servo motor (2) for driving the astronomical telescope (1), and a control system (4). A focusing servo motor (3) is connected to a lens regulation mechanism of the astronomical telescope (1); a CMOS sensor (5) used for obtaining a starry sky image is disposed on the astronomical telescope (1); the control system (4) includes a control chip, a gyroscope, a memory, and a WIFI communication interface; the control chip is electrically connected to the CMOS sensor (5), the gyroscope, the memory, and the WIFI communication interface; a handheld device provided with a WIFI communication interface is disposed by being fitted to the control system (4); and a GPS module is disposed in the control system (4) or the handheld device. Also provided is an automatic astronomical observation method.