A method and a system for interrogating an optical fiber includes a probe signal that has a first frequency comb at a first repetition rate (Δf) injected into the optical fiber. A backscattering signal that includes the probe signal convolved with an impulse response of the optical fiber in reflection which is sensitive to at least one parameter being measured from the optical fiber is gathered. The backscattering signal is beaten with a local oscillator signal to generate a beating signal, the local oscillator signal including a second frequency comb at a second repetition rate that is offset from the first repetition rate (Δf+δf) and being mutually coherent with the first frequency comb. The resulting beating signal is analysed to thereby determine the at least one parameter being measured from the optical fiber.

An optical filter, a spectrometer including the optical filter, and an electronic apparatus including the optical filter are disclosed. The optical filter includes a first reflector including a plurality of first structures that are periodically two-dimensionally arranged, each of the first structures having a ring shape, and a second reflector spaced apart from the first reflector and including a plurality of second structures that are periodically two-dimensionally arranged.

An optical filter, a spectrometer including the optical filter, and an electronic apparatus including the optical filter are disclosed. The optical filter includes a first reflector including a plurality of first structures that are periodically two-dimensionally arranged, each of the first structures having a ring shape, and a second reflector spaced apart from the first reflector and including a plurality of second structures that are periodically two-dimensionally arranged.

An optical filter may include an interference filter that passes at least two channels associated with at least two transmission peaks; and a plurality of blockers, wherein each blocker, of the plurality of blockers, passes a respective channel associated with a respective transmission peak of the at least two transmission peaks and blocks one or more channels other than the respective channel associated with the respective transmission peak.

A system for imaging a scene, includes a plurality of optical sensors arranged on an integrated circuit and a plurality of sets of interference filters, where each set of interference filters of the plurality of sets of interference filters includes a plurality of interference filters that are arranged in a pattern and each interference filter of the plurality of filters is configured to pass light in a different wavelength range, where each set of interference filters of the plurality of interference filters is associated with a spatial area of the scene. The system includes a plurality of rejection filters arranged in a pattern under each set of interference filters, where each rejection filter of the plurality of rejection filters is configured to substantially reject light of predetermined wavelengths. The system further includes one or more processors adapted to provide a spectral response for a spatial area of the scene associated with the set of interference filters.

A system for imaging a scene, includes a plurality of optical sensors arranged on an integrated circuit and a plurality of sets of interference filters, where each set of interference filters of the plurality of sets of interference filters includes a plurality of interference filters that are arranged in a pattern and each interference filter of the plurality of filters is configured to pass light in a different wavelength range, where each set of interference filters of the plurality of interference filters is associated with a spatial area of the scene. The system includes a plurality of rejection filters arranged in a pattern under each set of interference filters, where each rejection filter of the plurality of rejection filters is configured to substantially reject light of predetermined wavelengths. The system further includes one or more processors adapted to provide a spectral response for a spatial area of the scene associated with the set of interference filters.

An optical device includes an optical member having a plurality of first optical layers and a plurality of second optical layers having a refractive index different from that of the first optical layer in which the first optical layers and the second optical layers are laminated, and a layer thickness changing electrode that changes a thickness of the first optical layer in a lamination direction of the first optical layers and the second optical layers, in which the optical member is provided in a pair, and the pair of optical members is disposed to face each other through a gap, and a gap changing driver that changes a dimension of the gap.

An optical device includes an optical member having a plurality of first optical layers and a plurality of second optical layers having a refractive index different from that of the first optical layer in which the first optical layers and the second optical layers are laminated, and a layer thickness changing electrode that changes a thickness of the first optical layer in a lamination direction of the first optical layers and the second optical layers, in which the optical member is provided in a pair, and the pair of optical members is disposed to face each other through a gap, and a gap changing driver that changes a dimension of the gap.

Disclosed are embodiments of an improved apparatus and system, and associated methods for optically diagnosing a semiconductor manufacturing process. A hyperspectral imaging system is used to acquire spectrally-resolved images of emissions from the plasma, in a plasma processing system. Acquired hyperspectral images may be used to determine the chemical composition of the plasma and the plasma process endpoint. Alternatively, a hyperspectral imaging system is used to acquire spectrally-resolved images of a substrate before, during, or after processing, to determine properties of the substrate or layers and features formed on the substrate, including whether a process endpoint has been reached; or before or after processing, for inspecting the substrate condition.

Optical spectrometers may be used to determine the spectral components of electromagnetic waves. Spectrometers may be large, bulky devices and may require waves to enter at a nearly direct angle of incidence in order to record a measurement. What is disclosed is an ultra-compact spectrometer with nanophotonic components as light dispersion technology. Nanophotonic components may contain metasurfaces and Bragg filters. Each metasurface may contain light scattering nanostructures that may be randomized to create a large input angle, and the Bragg filter may result in the light dispersion independent of the input angle. The spectrometer may be capable of handling about 200 nm bandwidth. The ultra-compact spectrometer may be able to read image data in the visible (400-600 nm) and to read spectral data in the near-infrared (700-900 nm) wavelength range. The surface area of the spectrometer may be about 1 mm.sup.2, allowing it to fit on mobile devices.