An optical device includes a substrate and a stack of layers including metal oxides. Another optical device includes a stack of layers including metal oxides and a surface treating agent. A method of making an optical device is also disclosed.

An optical device formed of a mirror wafer, a cap wafer, and a glass wafer. The mirror wafer includes a first layer of electrically conductive material, a second layer of electrically conductive material, and a third layer of electrically insulating material between the first layer and the second layer. A mirror element is formed of the second layer of the mirror wafer, and has a reflective surface in the bottom of a cavity opened into at least the first layer. A good optical quality planar glass wafer can be used to enclose the mirror element when the mirror wafer, cap wafer, and glass wafer are bonded to each other.

An optical device includes a substrate and a coating applied to the substrate, wherein the optical device has a first side exposed to an environment and a second side that is unexposed.

A bandpass filter may include a set of layers. The set of layers may include a first subset of layers. The first subset of layers may include hydrogenated germanium (Ge:H) with a first refractive index. The set of layers may include a second subset of layers. The second subset of layers may include a material with a second refractive index. The second refractive index may be less than the first refractive index.

There is provided a filter for filtering electromagnetic radiation, wherein said filter is arranged to transmit electromagnetic radiation of a first predetermined wavelength and to block transmission of electromagnetic radiation of a second, different predetermined wavelength; said filter comprising a first metamaterial. Optionally, the metamaterial may be formed of a plurality of material elements wherein each material element is at least one-dimensional and the size of the material element along each dimension is no greater than the size of the second predetermined wavelength. The filter comprises a second metamaterial arranged to provide second filtering of electromagnetic radiation.

A bandpass filter may include a set of layers. The set of layers may include a first subset of layers. The first subset of layers may include hydrogenated germanium (Ge:H) with a first refractive index. The set of layers may include a second subset of layers. The second subset of layers may include a material with a second refractive index. The second refractive index may be less than the first refractive index.

A dielectric mirror is provided that, on the one hand exhibits a high destruction threshold when being irradiated with ultrashort high-power laser pulses, and on the other hand has a large bandwidth of group delay dispersion. The dielectric mirror includes a layer stack with a sequence of layers having different refractive indices, which act as a reflecting interference filter, wherein the layers are formed of at least three different materials exhibiting different destruction thresholds.

A bandpass filter may include a set of layers. The set of layers may include a first subset of layers. The first subset of layers may include hydrogenated germanium (Ge:H) with a first refractive index. The set of layers may include a second subset of layers. The second subset of layers may include a material with a second refractive index. The second refractive index may be less than the first refractive index.

Devices are provided, including a housing defining at least one window, a broadband UVC light source, and a multilayer article positioned within the housing. The multilayer article includes an absorbent layer and an ultraviolet mirror containing at least a plurality of alternating first and second optical layers. The absorbent layer absorbs and/or scatters ultraviolet light having a wavelength between at least 230 nanometers (nm) and 400 nm. The ultraviolet mirror reflects ultraviolet light in a wavelength range from 190 nm to 240 nm. Methods of disinfecting a material are also provided, including obtaining a device and directing ultraviolet radiation through the window, and exposing the material to the ultraviolet radiation for a time sufficient to achieve a desired degree of disinfection of the material. Systems and computing devices including the device are also provided.

A protective material that includes a dielectric mirror having at least one layer, each layer of the dielectric mirror being configured to reflect at least a portion of incident energy of a predetermined wavelength; and a photonic, crystal array of periodic structures disposed within the dielectric mirror, the photonic crystal array of periodic structures being configured to disperse non-reflected incident energy of the predetermined wavelength transmitted through the dielectric mirror across the photonic crystal array of periodic structures in a direction parallel to a plane of the dielectric mirror.