A HUD system including a light source projecting p-polarized light towards a glazing, the glazing includes an outer sheet of glass having a first surface and a second surface, and an inner sheet of glass having a first surface and a second surface, and the second surface of the inner sheet of glass has a first coating, where both sheets are bonded by at least one sheet of interlayer material, and the first coating includes at least one high refractive index layer having a thickness from 50 to 100 nm, and at least one low refractive index layer having a thickness from 70 to 160 nm, and the least one high refractive index layer has at least one of an oxide of Zr, Nb, Sn; a mixed oxide of Ti, Zr, Nb, Si, Sb, Sn, Zn, In; a nitride of Si, Zr; or a mixed nitride of Si, Zr.

An aerospace mirror having a reaction bonded (RB) silicon carbide (SiC) mirror substrate, and a SiC cladding on the RB SiC mirror substrate forming an optical surface on a front side of the aerospace mirror. A method for manufacturing an aerospace mirror comprising obtaining a green mirror preform comprising porous carbon, silicon carbide (SiC), or both, the green mirror preform defining a front side of the aerospace mirror and a back side of the aerospace mirror opposite the front side; removing material from the green mirror preform to form support ribs on the back side; infiltrating the green mirror preform with silicon to create a reaction bonded (RB) SiC mirror substrate from the green mirror preform; forming a mounting interface surface on the back side of the aerospace mirror from the RB SiC mirror substrate, and forming a reflector surface of the RB SiC mirror substrate on the front side of the aerospace mirror. Additionally, the method can comprise cladding the reflector surface of the RB SiC mirror substrate with SiC to form an optical surface of the aerospace mirror.

A catadioptric lens includes at least two optical elements arranged along an optical axis. Both optical elements are configured as a mirror having a substrate and a highly reflective coating applied to an interface of the substrate. The highly reflective coating extends from the interface of the substrate along a surface normal. At least one of the highly reflective coatings has one or a plurality of layers. The optical total layer thickness of the one layer of the plurality of layers increases radially from the inner area outward.

The disclosed structure is configured such that it does not support electromagnetic waves having frequencies within a selected band gap; those electromagnetic waves are thus reflected. Some variations provide an omnidirectional infrared reflector comprising a three-dimensional photonic crystal containing: rods of a first material that has a first refractive index, wherein the rods are arranged to form a plurality of lattice periods in three dimensions, and wherein the rods are connected at a plurality of nodes; and a second material that has a refractive index that is lower than the first refractive index, wherein the rods are embedded in the second material. The lattice spacing and the rod radius or width are selected to produce a photonic band gap within a selected band of the infrared spectrum. Methods of making and using the three-dimensional photonic crystal are described. Applications include thermal barrier coatings and blackbody emission signature control.

A delay mirror 1 includes a base 2, and an optical multilayer film 4 formed on a surface R of the base 2. The value of a group delay in a first wavelength band according to the optical multilayer film 4 is different from the value of the group delay in the second wavelength band according to the optical multilayer film 4, and the value of a group delay dispersion in the first wavelength band according to the optical multilayer film 4 and the value of the group delay dispersion in the second wavelength band according to the optical multilayer film 4 are each not less than −100 fs.sup.2 and not greater than 100 fs.sup.2. Further, the delay mirror system includes a delay mirror movement mechanism which moves the delay mirror 1 such that the number of times of reflection is changed.

An optical element includes: a substrate, a reflective coating, applied to the substrate, for reflecting radiation in a first wavelength range (Δλ.sub.1) between 100 nm and 700 nm, preferably between 100 nm and 300 nm, more preferably between 100 nm and 200 nm, and a protective coating applied to the reflective coating. The substrate is formed from a material which is transparent to the radiation in the first wavelength range (Δλ.sub.1). The reflective coating is applied to a rear face of the substrate and is structured to reflect radiation that passes through the substrate to the reflective coating. Also disclosed are an optical arrangement with at least one such optical element and a method of producing such an optical element.

Methods, apparatuses and systems for providing optical coatings for optical components are disclosed herein. An example optical component may comprise an optical coating, the optical coating having a visible light reflective layer disposed adjacent a surface of the optical component; at least a first non-visible light reflective layer disposed adjacent the visible light reflective layer; and at least a second non-visible light reflective layer disposed adjacent the first non-visible light reflective layer.

According to the present disclosure, an optical lens assembly includes at least two optical lens elements and at least one reflective element. The reflective element is made of a plastic material, the reflective element includes a reflective coating membrane, and the reflective coating membrane is disposed on a surface of the reflective element. The reflective coating membrane includes at least three coating layers of different materials, the at least three coating layers are respectively made of a first material, a second material and a third material, the first material mainly includes silver, the second material mainly includes titanium, the third material mainly includes chromium oxides, and the coating layer made of the first material and the coating layer made of the second material are disposed between the coating layer made of the third material and the reflective element.

A film comprises an amorphous transition metal oxide as a main component, and 1.0 at % or more of hydrogen.

A light-receiving element, comprising a plurality of photodiodes formed by stacking in this sequence, a lower reflection mirror, a resonator including a photoelectric conversion layer, and an upper reflection mirror on a semiconductor substrate, wherein the plurality of photodiodes share the semiconductor substrate and the lower reflection mirror, the plurality of photodiodes includes a first photodiode having a resonance wavelength λ1 and a second photodiode having a resonance wavelength λ2 that is larger than the resonance wavelength λ1, and a reflectance of the lower reflection mirror has a first peak corresponding to the resonance wavelength λ1 and a second peak corresponding to the resonance wavelength λ2.