An optical system with an entrance pupil, has a first aperture diameter, an exit pupil and a reflective or transmissive filter element spaced at a distance from the entrance pupil, which is designed and arranged such that a second diameter is illuminated on the filter element by a beam passing through the entrance pupil and spreading divergently from this. The second diameter corresponds to n times the first aperture diameter, and n is a number greater than 1, as a result of which the local angular spectrum at each point on the filter element is n times smaller in comparison to the entrance pupil. The filter element selectively reflects or transmits to the exit pupil at each point only a predetermined spectral range. An optical imaging unit comprising the filter element is provided, which images the entrance pupil onto the exit pupil.

A color developing structure that exhibits good color development and ensures a desired transmittance while diffusing reflected light in multiple directions. A color developing structure includes a concave-convex layer in which a first surface has a concave-convex structure, and a reflective layer formed on the first surface to extend along the concave-convex structure. A convex surface of the concave-convex structure has a first pattern composed of a plurality of strip portions in plan view. The strip portion has a width in a first direction and a length in a second direction perpendicular to the first direction. The width is smaller than the wavelength of the incident light, and a standard deviation of the lengths of the plurality of strip portions is larger than a standard deviation of the widths.

A sub-wavelength grating optical film comprises a plurality of one-dimensional periodic grating units repeatedly arranged side by side. Each grating unit with a period of p comprises a first medium, a second medium, a third material, a fourth material, a fifth material, a sixth medium and a seventh medium, wherein the sixth medium serving as a substrate and the seventh medium serving as a covering layer are respectively arranged on bottom and top of each grating unit periodically arranged side by side. By controlling grating period and refractive index, incident blue-violet light meets condition that a diffraction angle in a layer with highest refractive index is smaller than 90 degrees; and by adjusting duty ratio of the grating and the thickness of each layer of material, transmitted light energy of the blue-violet light wave band is the lowest so that harmful blue-violet light is isolated.

A light-emitting device includes: a light guide that includes (i) a light-transmissive member that is light-transmissive at least in a visible light region and (ii) a light control layer that is disposed on at least a part of a surface of the light-transmissive member; and a light source that emits light toward at least one end surface of the light-transmissive member. The light control layer has reflected-wavelength selectivity that makes a wavelength of reflected light dependent on an incident angle of incident light.

A device includes a diffraction element and an optical filter stacked with the diffraction element. The optical filter is configured to forwardly deflect a light from a real-world environment incident onto the optical filter, at an incidence angle greater than or equal to a predetermined angle, toward the diffraction element. The diffraction element is configured to substantially transmit the light forwardly deflected by the optical filter.

A diffractive beam expander device (EPE1) includes a first spectral filter region (C2a) and a second spectral filter region (C2b) to provide a first optical route for blue and green light (B, G), and to provide a second optical router for red light (R). The expander device (EPE1) includes a first Bragg grating region (BRGa) to enhance optical absorption of red light (R) in the first spectral filter region (C2a). The expander device (EPE1) includes a second Bragg grating region (BRGa) to enhance optical absorption of blue light (B) in the second spectral filter region (C2b).

In a method for producing an optical element for an EUV projection exposure apparatus, a shaping layer (22.sub.1) is applied onto a substrate (20) so as to have a surface roughness of at most 0.5 nm rms directly after the application of the shaping layer onto the substrate.

Initiator/mediator chemistry for latent imaging polymers for volume Bragg gratings is provided. Light mediated chemistry including the use of nitroxides allows a first step imaging to occur, where a light induced pattern is recorded in the material, without the grating being apparent. A second bleaching/developing step completes the curing process and reveals the grating.

A laminate, includes: a first layer, a first material of the first layer having a first refractive index, the first layer including a first surface; a first microstructure layer including a first microstructure pattern formed on a first surface of the microstructure layer, a first microstructure material of the first microstructure layer having a first microstructure material refractive index, the first microstructure pattern having first repeating structures with a first predetermined periodicity, the microstructure layer being disposed on the first surface of the first layer; a second layer, a second material of the second layer having a second refractive index, the second layer being disposed adjacent to the first surface of the first microstructure layer; and a third layer, a third material of the third layer having a third refractive index, the third layer being disposed adjacent to the second layer on a side opposite the microstructure layer.

Methods, apparatus, devices, and systems for displaying three-dimensional objects by individually diffracting different colors of light are provided. In one aspect, an optical device includes: a first optically diffractive component including a first diffractive structure configured to diffract a first color of light having a first incident angle at a first diffracted angle, a second optically diffractive component including a second diffractive structure configured to diffract a second color of light having a second incident angle at a second diffracted angle, a first reflective layer configured to totally reflect the first color of light having the first incident angle and transmit the second color of light, and a second reflective layer configured to totally reflect the second color of light having the second incident angle. The first reflective layer is between the first and second diffractive structures, and the second diffractive structure is between the first and second reflective layers.