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 three-aspherical-mirror anastigmat telescope comprises means for moving the third mirror linearly along the optical axis of the telescope so as to make the focal length of the telescope change to a plurality of focal lengths between at least a minimum focal length and a maximum focal length, a plurality of aspherical optical components respectively associated with the plurality of focal lengths, the third mirror having a new conicity determined from an initial conicity, the new conicity being determined so that the telescope has, in the absence of the aspherical components and for the minimum and maximum focal lengths, aberrations that are compensable by the aspherical components, the position and the form of the surface of each aspherical component being determined so as to correct the compensable aberrations of the telescope for the associated focal length and to optimize image quality in the first focal plane of the telescope according to a preset criterion.

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.

An image display apparatus including a first light source, a spherical lens configured to receive light output from the first light source, an aspherical lens configured to receive light output from the spherical lens, a first free curved mirror configured to receive light output from the aspherical lens is incident, a second free curved mirror configured to receive light output from the first free curved mirror, a third free curved mirror configured to receive light output from the second free curved mirror, and an image display panel configured to receive light output from the third free curved mirror and configured to display image information, wherein a light path of the light output from the first free curved mirror, a light path of the light output from the second free curved mirror, and a light path of the light output from the third free curved mirror intersect each other.

An inspection device for inspecting a panel, in particular a display, or a PCB, includes a first mirror, a second mirror, a third mirror, and a sensor. The first mirror, the second mirror, and the third mirror are arranged to display a section of the panel to be inspected on the sensor with a magnification factor greater than one. At least two of the group of the first mirror, the second mirror, and the third mirror, have both a first type of curvature, and a remaining mirror has a second type of curvature, opposite to the first type of curvature. The first mirror, the second mirror, and the third mirror form a telecentric system which is telecentric on a panel facing side and/or on a sensor facing side.

An out-of-field rejection filter (OFRF) can be used in optical systems to reject stray light. Such optical systems can include cameras, projectors, star trackers, and virtual reality or augmented reality displays. The OFRF can include a converter to convert randomly polarized light to p-polarized light and an angular selectivity layer to select in-field p-polarized light and reject out-of-field p-polarized light. The converter and the angular selectivity layer are configured so as to filter out-of-field light while passing in-field light within a light bandwidth. The angular selectivity layer can be a multilayer film of interleaved materials having alternating permittivity and magnetic permeability properties.

A cloaking device includes an object-side, an image-side, an object-side curved cloaking region (CR) boundary having an outward facing mirror surface and an inward facing surface, and an image-side curved CR boundary an outward facing mirror surface and an inward facing surface. A cloaked region is bounded by the inward facing surfaces of the object-side curved CR boundary and the image-side curved CR boundary. At least one exterior boundary with an inward facing mirror surface is spaced apart from the object-side curved CR boundary and the image-side curved CR boundary. Light from an object positioned on the object-side of the cloaking device and obscured by the cloaked region is redirected around the cloaked region to form an image of the object on the image-side of the cloaking device such that the light from the object appears to pass through the CR.

A freeform surface off-axial three-mirror imaging system comprising a primary mirror, a secondary mirror, a tertiary mirror, and a detector. The secondary mirror comprises a first freeform surface and a second freeform surface. Each reflective surface of the primary mirror, the first freeform surface, the second freeform surface and the tertiary mirror is an xy polynomial freeform surface. The freeform surface off-axial three-mirror imaging system comprises a first field of view formed by the first freeform surface and a second field of view formed by the second freeform surface.

A freeform surface off-axial three-mirror imaging system comprising a primary mirror, a secondary mirror, a tertiary mirror, and a detector. The secondary mirror comprises a first freeform surface and a second freeform surface. Each reflective surface of the primary mirror, the first freeform surface, the second freeform surface and the tertiary mirror is an xy polynomial freeform surface. The freeform surface off-axial three-mirror imaging system comprises a first effective focal length and a second effective focal length different from the first effective focal length.

A freeform surface off-axial three-mirror imaging system comprising a primary mirror, a secondary mirror, a tertiary mirror, and a detector. The secondary mirror defines a first location and a second location. Each reflective surface of the primary mirror, the secondary mirror and the tertiary mirror is an xy polynomial freeform surface. A working distance of the freeform surface off-axial three-mirror imaging system is greater than 125 mm.