A freeform surface off-axial three-mirror image-side telecentric optical system comprises a primary mirror, a secondary mirror, a tertiary mirror and an image sensor. The secondary mirror is the aperture stop. A reflective surface of the primary mirror is a fourth-order polynomial freeform surface of xy. Each of a reflective surface of the secondary mirror and a reflective surface of the tertiary mirror is a sixth-order polynomial freeform surface of xy.

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 displaying system includes a display unit, a projection unit, and a light-transmissive member. The display unit is configured to display an image. The projection unit is configured to reflect rays of light constituting the image toward a reflective member to project the image onto the reflective member to form a virtual image in a target space. The light-transmissive member has a plate shape. The light-transmissive member is located between the reflective member and the projection unit. The light-transmissive member intersects with an optical axis of light traveling from the projection unit toward the reflective member without forming right angles. The light-transmissive member has in-plane retardation and thickness direction retardation larger than the in-plane retardation.

A vehicular display device includes a display that emits, as display light, a display image projected onto a windshield, a transparent cover that blocks an opening of a housing and transmits at least a part of the display light emitted from the display, a plurality of reflecting mirrors, and a quarter wave plate. Using a vibration direction of the display light from the display as a reference vibration direction, the quarter wave plate converts the display light transmitted from the transparent cover toward the reflecting mirror into circularly polarized light vibrating in a direction tilted by 45 degree from the reference vibration direction and converts the circularly polarized light transmitted toward the reflecting mirror from the reflecting mirror into display light vibrating in a direction orthogonal to the reference vibration direction.

A three-mirror anastigmat telescope comprises at least a concave first mirror, a convex second mirror and a concave third mirror, the three mirrors arranged so that the first mirror and the second mirror form, from an object at infinity, an intermediate image situated between the second mirror and the third mirror, the third mirror forming, from this intermediate image, a final image in the focal plane of the telescope. In the architecture of the telescope, at least the surface of the concave third mirror is a -polynomial surface.

A oblique camera lens includes: a primary mirror configured to reflect a light ray to form a first reflected light; a secondary mirror located on a first path of light reflected from the primary mirror and configured to reflect the first reflected light to form a second reflected light; a tertiary mirror located on a second path of light reflected from the secondary mirror and configured to reflect the second reflected light to form a third reflected light; and an image sensor located on a third path of light reflected from the tertiary mirror and configured to receive the third reflected light; wherein each of the first reflecting surface and the third reflecting surface is a sixth order xy polynomial freeform surface; and a field of view of oblique camera lens in an Y-axis direction is greater or equal to 35 and less than or equal to 65.

An image projection device that can effectively use a space to achieve space saving even when projection light from an image projecting unit is reflected by a plurality of freeform curved mirrors to reach a viewpoint is provided. The image projection device includes: an image projecting unit emitting projection light including an image; a first freeform curved mirror reflecting the projection light incident from the image projecting unit; and a second freeform curved mirror reflecting the projection light incident from the first freeform curved mirror and causing the projection light to reach a viewpoint. Only one of an x-axis component and a y-axis component of the projection light reflected by the first freeform curved mirror forms an image between the first freeform curved mirror and the second freeform curved mirror.

An off-axis aspheric three-mirror optical system comprises a primary mirror, a secondary mirror, and a tertiary mirror. Relative to a first three-dimensional rectangular coordinates system in space, a second three-dimensional rectangular coordinates system is defined by a primary mirror location, a third three-dimensional rectangular coordinates system is defined by a secondary mirror location, and a fourth three-dimensional rectangular coordinates system is defined by a tertiary mirror location. The primary mirror in the second three-dimensional rectangular coordinates system, the secondary mirror in the third three-dimensional rectangular coordinates system, and the tertiary mirror in the fourth three-dimensional rectangular coordinates system are all sixth-order polynomial aspheric.

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 601. An F-number of the freeform surface off-axial three-mirror imaging system is less than or equal to 2.5.

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.