A freeform surface off-axial three-mirror imaging system comprising a primary mirror, a secondary mirror, a tertiary mirror, and an image sensor. Each reflective surface of the primary mirror, the secondary mirror, and the tertiary mirror is an xy polynomial freeform surface. A field angle of the freeform surface off-axial three-mirror imaging system is larger than or equal to 60°×1°. An F-number of the freeform surface off-axial three-mirror imaging system is less than or equal to 2.5.

An all-reflective or reflective and cata-dioptric optical system is described including a concave primary mirror having a central aperture and a radius, the primary mirror having one of a parabolic, non-parabolic conical, or aspherical surface, a convex secondary mirror facing the primary mirror, the secondary mirror having an aspherical surface, where an optical axis extends from a vertex of the primary mirror to a vertex of the secondary mirror, a concave tertiary mirror arranged behind the primary mirror, the tertiary mirror having one of a parabolic, non-parabolic conical or aspherical surface, a concave quaternary mirror arranged in the central aperture of the primary mirror or behind the primary mirror, the quaternary mirror having one of a spherical, parabolic, non-parabolic conical or aspherical surface, and/or at least one image plane having one or more aggregated sensors. Additional multispectral imaging may utilize beam splitter(s), folding mirror(s), focal length optimizer(s) and/or additional image planes.

A luminous device for a motor vehicle, said device including a pixelized light source and an optical system that is arranged to project a pixelized light beam emitted by the pixelized light source, the optical system comprising a first mirror arranged to collect and reflect rays of the pixelized light beam emitted by the pixelized light source, a second mirror arranged to reflect the rays reflected by the first mirror, and a third mirror arranged to receive the rays reflected by the second mirror and to reflect these received rays so as to correct field aberrations. The invention enables improved projection of a pixelized light beam by a luminous motor-vehicle device.

The present invention relates to a method for designing a freeform surface reflective imaging system, comprising: selecting an initial system, wherein an FOV of the initial system is X.sub.0×Y.sub.0; selecting an FOV sequence as [X.sub.0, Y.sub.0], [X.sub.1, Y.sub.1], [X.sub.2, Y.sub.2], . . . , [X.sub.n, Y.sub.n], while the FOV of the system to be designed is X.sub.n×Y.sub.n, and X.sub.0<X.sub.1<X.sub.2< . . . <X.sub.n, Y.sub.0<Y.sub.1<Y.sub.2< . . . <Y.sub.n; using point-by-point methods to construct all freeform surfaces of the initial system in the FOV of X.sub.1×Y.sub.1; setting the system obtained in the last step as a second initial system for system construction in the FOV of X.sub.2×Y.sub.2; repeating the last step to execute system construction in the order of the FOV sequence until the final FOV X.sub.n×Y.sub.n is obtained.

A three-aspherical-mirror anastigmat telescope comprises: means for moving the third mirror linearly along the optical axis of the telescope to make the focal length of the telescope change between a minimum focal length and a maximum focal length, a deformable and controllable mirror, means for changing the optical path between the deformable mirror and the detector, the third mirror having a new conicity determined from an initial conicity, the initial conicity determined from the Korsch equations, the new conicity determined so that the telescope has, in the absence of the deformable mirror and for the minimum and maximum focal lengths, aberrations that are compensable by the deformable mirror, the fixed median position of the deformable mirror and the form of its surface, for the minimum focal length and maximum focal length, respectively, being determined so as to correct the compensable aberrations and to optimize image quality in the focal plane of the telescope according to a preset criterion.

The present disclosure relates to a method of designing a freeform surface off-axial imaging system. The method comprises the steps of establishing an initial system and selecting feature fields; gradually enlarging a construction of feature field, and constructing the initial system into a freeform surface system; and expanding a construction area of each freeform surface of the freeform surface system, and reconstructing the freeform surface in an extended construction area.

Systems and methods of the present disclosure are directed to optics used in absorption cell spectrometers. The absorption cell includes a plurality of mirrors arranged in a manner such that a detection light traverses multiple passes through the fluid within the absorption cell. In some implementations, the detection light is reflected by the plurality of mirrors to form optical paths in more than one plane. In some implementations, the orientation of the mirrors are aligned with specific orientations to provide the desired optical path to the detection light. In one or more embodiments, an alignment apparatus can be used to pre-align the mirrors before they are placed within the absorption cell. The alignment apparatus includes an aperture plate and an adjustable mount to mount one or more mirrors. The mirrors are aligned based on reflected images on the aperture plate laser light incident on the mirrors.

An optical element includes a substrate, a first resin portion provided on a first main surface of the substrate and having a linear expansion coefficient larger than a linear expansion coefficient of the substrate, a reflection portion provided on the first resin portion, and a second resin portion provided on a second main surface of the substrate opposite to the first main surface and having a linear expansion coefficient larger than the linear expansion coefficient of the substrate.

The present invention relates to a method for designing a freeform surface reflective imaging system, comprising: selecting an initial system, wherein an FOV of the initial system is X.sub.0Y.sub.0; selecting an FOV sequence as [X.sub.0, Y.sub.0], [X.sub.1, Y.sub.1], [X.sub.2, Y.sub.2], . . . , [X.sub.n, Y.sub.n], while the FOV of the system to be designed is X.sub.nY.sub.n, and X.sub.0<X.sub.1<X.sub.2< . . . <X.sub.n, Y.sub.0<Y.sub.1<Y.sub.2< . . . <Y.sub.n; using point-by-point methods to construct all freeform surfaces of the initial system in the FOV of X.sub.1Y.sub.1; setting the system obtained in the last step as a second initial system for system construction in the FOV of X.sub.2Y.sub.2; repeating the last step to execute system construction in the order of the FOV sequence until the final FOV X.sub.nY.sub.n is obtained.

A freeform surface off-axial three-mirror imaging system is provided. The freeform surface off-axial three-mirror imaging system comprises a primary mirror, a secondary mirror, and a compensating mirror. The primary mirror, the secondary mirror, and the compensating mirror are located adjacent and spaced away from each other. A surface shape of each of the primary mirror and the secondary mirror is a quadric surface. The primary mirror is used as an aperture stop. A surface shape of the compensating mirror is a freeform surface. A light emitted from a light source is reflected by the primary mirror, the secondary mirror, and the compensating mirror to form an image on an image plane.