An optical system of the present disclosure includes: a first optical system including a polarization conversion element aligning a polarization direction of light including color light beams with a predetermined polarization direction, and generating illumination light including the color light beams; a first polarization rotation element disposed at a first pupil position inside the first optical system, including first and second divided regions, in which the first and second divided regions have different polarization characteristics with respect to a first color light beam outputted from the polarization conversion element; a polarizer disposed between the polarization conversion element and the first polarization rotation element, and reducing light in a polarization direction other than the predetermined polarization direction included in light outputted from the polarization conversion element; and light valves each illuminated by at least the first color light beam included in the illumination light generated by the first optical system.

An optical device includes a reflector-section that includes a light-ingress surface for receiving light from a light source, a reflector surface for reflecting the light based on total internal reflection, and a light-egress surface through which the reflected light exits the optical device. When the light source is at a predetermined position with respect to the optical device, an angle of incidence (θ.sub.i) of the light at the light-egress surface is a polarization angle at which a p-polarized component of the light is transmitted through the light-egress surface without being reflected by the light-egress surface. Thus, unwanted reflections at the light-egress surface can be reduced and thereby unwanted scattering of light is reduced while having good transmitting efficacy.

A projection exposure apparatus for semiconductor lithography comprises an optical element and a temperature recording device for detecting a temperature on a surface of the optical element via electromagnetic radiation emanating from the surface of the optical element. The temperature recording device can comprise a filter for filtering the electromagnetic radiation.

A reflective polarizing imaging lens includes at least one optical film having an active area that is curved in two orthogonal directions. Edges of the optical film are arranged to form seams between segments of the optical film in the active area of the reflective polarizing imaging lens.

Polarization-based optical angle-filters disclosed herein can be engineered to transmit a prescribed amount of light as a function of incidence angle and azimuth. Such filters can transmit light without introducing artifacts, making them suitable for the image-path of an optical system. One example may include an angle-filter having an input circular polarizer, an analyzing circular polarizer, and a retarder positioned between the circular polarizers, the retarder having a thickness-direction retardation. The thickness-direction retardation of the retarder (R.sub.th) is selected to produce a prescribed angle-of-incidence dependent transmission function, and the circular polarizers reduce the amount of azimuth-dependence in the transmission function.

An optical system includes a display including an active display region configured to emit an image. The active display region includes a predetermined region including a display center. A windshield of a vehicle includes an embedded reflective polarizer. The reflective polarizer reflects between about 20% to about 40% of incident light polarized along a first direction, and transmits at least 60% of the incident light polarized along a second direction. The reflective polarizer receives the image emitted by the active display region and reflects a portion toward the eye. For at least one first location within the predetermined region, the emitted image includes an image cone having an emitted central image ray emitted from the first location. The emitted central image ray is polarized along a third direction when incident on the windshield in an incident plane. The first and third directions are substantially parallel to the incident plane.

An optical system includes a display system including a display having first and second display pixels interspersed with each other across the display. The first and second display pixels emit superimposed different respective first and second images polarized along the first direction. The display system includes a patterned retarder having pluralities of first and second retarder pixels aligned and registered with the respective first and second display pixels in one-to-one correspondence. The first retarder pixels are configured to receive and transmit the first emitted image as the first output image polarized along the first direction. The second retarder pixels are configured to receive, change the polarization direction, and transmit the second emitted image as the second output image polarized along the second direction. A reflective polarizer is configured to receive the first and second output images and substantially transmit the first output image and substantially reflect the second output image.

An optical device can include: an incident light polarizer positioned to receive incident light and configured to polarize incident light such that polarized incident light is directed to a cornea of a subject; at least one corneal light polarizer, wherein the at least one corneal light polarizer is positioned to receive reflected light from the cornea of the subject and polarize the reflected light to a second polarization; at least one rotating mechanism; and at least one receiver. The receiver can be at least one viewing port optically coupled with the at least one corneal light polarizer or an imaging device (e.g., optical detector). The at least one rotating mechanism is: coupled with the incident light polarizer; coupled with the at least one corneal light polarizer; or coupled with the incident light polarizer and the at least one corneal light polarizer.

A heads-up display includes a windshield (10) with a standardized wedge profile and an embedded reflective polarizer (20) for p-polarised light and a display (40). The reflective polarizer is disposed between, and spaced apart from, opposing outermost first and second major glass surfaces (11, 12) of the windshield. The heads-up display forms a virtual image for viewing by the eye of a passenger. An image emitted by the display may include a first image ray emitted from a predetermined region of the display and incident on the outermost first major glass surface of the windshield at an angle of incidence greater than about 60 degrees, with at least 90% of the incident first emitted image ray polarized in a plane of incidence of the first emitted image ray. A heads-up display includes windshield (10) with a standardized wedge profile and an embedded reflective polarizer (20) for p-polarised light and a display (40). The reflective polarizer is disposed between, and spaced apart from, opposing outermost first and second major glass surfaces (11, 12) of the windshield. The heads-up display forms a virtual image for viewing by the eye of a passenger. An image emitted by the display may include a first image ray emitted from a predetermined region of the display and incident on the outermost first major glass surface of the windshield at an angle of incidence greater than about 60 degrees, with at least 90% of the incident first emitted image ray polarized in a plane of incidence of the first emitted image ray.

A projection arrangement for a head-up display, including a composite pane, including an outer pane and an inner pane, which are joined to one another via a thermoplastic intermediate layer, having an upper edge and a lower edge and an HUD region; an electrically conductive coating on the surface of the outer pane or the inner pane facing the intermediate layer or provided within the intermediate layer; and a projector that is aimed at the HUD region; wherein the light of the projector has at least one p-polarised portion and wherein the electrically conductive coating has, in the spectral range from 400 nm to 650 nm, only a single local reflection maximum for p-polarised light, with this maximum in the range from 510 nm to 550 nm.