One or more aspects of the present disclosure provide articles of manufacture and components of articles that incorporate an optical element that imparts structural color to the component or the article. The component comprises a cured or curable material, and can include or be made to have a textured surface.

There is provided a head-up display device which has a small size and of which the aberration is small and the range of an eye box in a vertical direction is wide. The head-up display device 10 includes a first optical system that includes at least one concave mirror arranged along an optical path of display light in order from an image display surface 1, and a second optical system that includes at least one concave mirror arranged along the optical path of the display light in order from the image display surface 1 side. An intermediate image is formed between the first and second optical systems on the optical path, and the first optical system includes a double reflection mirror that reflects the display light twice on the optical path.

The teachings of the present disclosure enable a reduction of the refractive index of a material by incorporating an additive selected from air, vacuum, or an inert gas in the material to turn the material into a material foam that is suitable for use in optical systems. A material foam in accordance with the present disclosure is characterized by a porosity that reduces its refractive index from that of the same material as found in nature. The higher porosity also decreases the density of the material from that of the same material as found in nature. Material foams in accordance with the present disclosure are suitable for use in the low-refractive-index layers of a Bragg mirror.

A micro-layered structure for use in an optical projection system is configured to reflect incident light as multiple closely aligned reflections. A first semi-reflective transparent layer of the structure has a first index of refraction, a first front surface and a first rear surface. A second semi-reflective transparent layer of the structure has a second index of refraction different from the first index of refraction, a second front surface and a second rear surface. The second front surface abuts the first rear surface of the first semi-reflective transparent layer. Portions of the incident light are respectively reflected by the first front surface, first rear surface, second front surface and second rear surface as first, second, third and fourth reflections which collectively form a projection of the image perceived by a user of the optical projection system.

A mirror arrangement (30) includes: a substrate (31) with a front side (31a) having a mirror face (32a) reflecting radiation (5), and a rear side (31b) facing away from the front side and on which at least one actuator (27) generating deformations of the mirror face is arranged. A water vapor (36)-sorbing material (33, 42) is formed on the rear side (31b) and forms an adhesive layer (33) for securing the actuator. The layer extends into interspaces (35) between the actuators (27). A surface (33a, 42a) of the water vapor-sorbing material is covered at least partly by a coating (37) which forms a water vapor diffusion barrier.

A mirror having a mirror substrate (12, 32, 52), a reflection layer stack (21, 41, 61) reflecting electromagnetic radiation having an operating wavelength that is incident on the optical effective surface (11, 31, 51), and at least one piezoelectric layer (16, 36, 56), arranged between the substrate and the reflection layer stack and to which an electric field producing a locally variable deformation is applied. A first electrode arrangement (20, 40, 60) situated on the side of the piezoelectric layer faces the reflection layer stack, and a second electrode arrangement (14, 34, 54) is situated on the side of the piezoelectric layer facing the mirror substrate. Optionally, a bracing layer (98) is provided, which limits sinking of the piezoelectric layer (96) into the mirror substrate (92) when an electric field is applied, in comparison with an analogous construction lacking the bracing layer, thereby increasing the piezoelectric layer's effective deflection.

An apparatus comprising a cavity having interior surfaces or reflecting elements, one or more transmitters configured to receive an electrical signal, transform the electrical signal into an electromagnetic wave signal, and introduce the electromagnetic wave signal into an inside of the cavity, and one or more receivers configured to retrieve the electromagnetic wave signal, transform the electromagnetic wave signal to a corresponding electrical signal, and transmit the corresponding electrical signal to the outside of the cavity is disclosed. The electromagnetic wave signal is contained within the inside of the cavity until retrieved by undergoing a series of reflections or traversals between the interior surfaces of the cavity or the reflecting elements within the cavity. The apparatus may further comprise one or more regenerators configured to re-amplify, re-shape, and/or re-time the electromagnetic wave signal traveling within the inside of the cavity.

An optical element (1) includes: a substrate (2); applied to the substrate (2), a multilayer system (3) which reflects EUV radiation (4); and also applied to the multilayer system (3), a protective layer system (5) which comprises a first layer (5a), a second layer (5b) and a third, in particular topmost layer (5c), where the first layer (5a) is disposed closer to the multilayer system (3) than the second layer (5b), and where the second layer (5b) is disposed closer to the multilayer system (3) than the third layer (5c). The second layer (5b) and the third layer (5c) and also preferably the first layer (5a) each have a thickness (d.sub.2, d.sub.3, d.sub.1) of between 0.5 nm and 5.0 nm. A related EUV lithography system having at least one such optical element is also described.

An extreme ultraviolet light condensation mirror includes a substrate, and a multi-layer reflective film provided on the substrate, formed by alternately stacking an amorphous silicon layer and a layer having a refractive index different from a refractive index of the amorphous silicon layer, and configured to reflect extreme ultraviolet light, a layer on a most surface side in the multi-layer reflective film being the amorphous silicon layer containing a silicon atom bonded with a cyano radical.

An optical device includes: a first reflector; a second reflector facing the reflector; a light emitter between the first reflector and the second reflector; a base supporting the second reflector with space between the light emitter and the second reflector; a piezoelectric body configured to, in response to application of drive voltage, deform to cause the second region to deform to drive the second reflector so as to change a distance between the first reflector and the second reflector. The base has a first region and a second region having a lower stiffness than the first region. The second region has the second reflector and the piezoelectric body thereon. The optical device is configured to emit a laser beam whose wavelength is changeable with the distance between the first reflector and the second reflector.