An optical system includes a reflective surface, a display adapted to emit image light toward the reflective surface, and a multilayer reflective polarizer disposed proximate the reflective surface. The multilayer reflective polarizer is curved about two orthogonal axes and includes at least one layer that is substantially optically uniaxial at at least one location. The image light is transmitted by the multilayer reflective polarizer after it is first reflected by the multilayer reflective polarizer. A head-mounted display includes a first optical system and a second optical system disposed proximate the first optical system.

Optical systems including an image surface, a stop surface, a partial reflector disposed between the image surface and the stop surface, a reflective polarizer disposed between the stop surface and the partial reflector, and a quarter wave retarder disposed between the reflective polarizer and the partial reflector are described. The reflective polarizer is convex along two orthogonal axes. The reflective polarizer may be a thermoformed multilayer reflective polarizer.

Techniques are disclosed for optical distortion reduction in projection systems for scanning projection and/or lithography. A projection system includes an illumination system configured to generate illumination radiation for generating an image of an object to be projected onto an image plane of the projection system. The illumination system includes a field omitting illumination condenser configured to receive the illumination radiation from a radiation source and provide a patterned illumination radiation beam to generate the image of the object, wherein the patterned illumination radiation beam comprises an omitted illumination portion corresponding to a ridge line of a roof prism disposed within an optical path of the projection system.

An optical system includes a reflective optical system on a magnification side along an optical path of the projection optical system and a refractive optical system on a reduction side along the optical path. The reflective optical system includes one reflective optical element having a power. The refractive optical system includes a front group on the magnification side and a rear group on the reduction side. The front group having, in order from the magnification side toward the reduction side, a first lens group with a positive or negative refractive power, a second lens group, and a third lens group with a positive refractive power. The rear group has a positive refractive power. The first lens group moves to the magnification side, and the second lens group and the third lens group move to the reduction side in a change in focus from a long distance to a short distance.

Methods and apparatus for implementing a camera having a depth which is less than the maximum length of the outer lens of at least one optical chain of the camera are described. In some embodiments a light redirection device, e.g., a mirror, is used to allow a relatively long optical chain with a relatively large non-circular outer lens. In some embodiments the light redirection device has a depth, e.g., front of camera to back of camera dimension, which is less than the maximum length of the aperture of the outer lens in the aperture's direction of maximum extent. Multiple optical chains with non-circular outer lenses arranged in different directions may and in some embodiments are used to capture images with the captured images being combined to generate a composite image.

Optical systems including an image surface, a stop surface, a partial reflector disposed between the image surface and the stop surface, a reflective polarizer disposed between the stop surface and the partial reflector, and a quarter wave retarder disposed between the reflective polarizer and the partial reflector are described. The reflective polarizer is convex along two orthogonal axes. The reflective polarizer may be a thermoformed multilayer reflective polarizer.

A compact, uniaxially-aligned series of lenses are shaped and coated to allow coaxial viewing of two different fields of view on the same focal-plane array by selecting a type of light. The selection can be, for example, by spectrum or polarization. Zonal coatings on the lens surfaces permit for a catadioptric narrow field-of-view light path. The lens assembly accomplishes simultaneous dual field-of-view in a durable package without respective motion of optical elements, without substantial gaps between the lenses, and at lower cost than other assemblies.

An optical stack includes first and second lenses, a partial reflector, a reflective polarizer, and a retarder. The reflective polarizer is curved about two orthogonal axes and includes at least one layer that is substantially optically uniaxial at at least one location. An optical system includes the optical stack disposed between an image surface and an exit surface. The optical system is configured such that substantially any chief ray transmitted from the image surface to the exit surface is first incident on the reflective polarizer at an angle of incidence less than 30 degrees.

A camera including an aperture, an image recording device, a reflective polarizer disposed between the aperture and the image recording device, a partial reflector disposed between the reflective polarizer and the image recording device, and a quarter wave retarder disposed between the reflective polarizer and the partial reflector. The reflective polarizer is curved about two orthogonal axes.

Imaging objectives and inspection systems equipped with such imaging objectives are disclosed. The imaging objective may include a front objective configured to produce a diffraction limited intermediate image. The imaging objective may also include a relay configured to receive the intermediate image produced by the front objective. The relay may include three spherical mirrors positioned to deliver a projection of the intermediate image to a fixed image plane.