The present disclosure relates to a dispersion apparatus. The dispersion apparatus may include an optical substrate; a grating layer on a first side of the optical substrate; and a light outlet layer on a second side of the optical substrate, the second side opposite the first side of the optical substrate. The grating layer is configured to perform dispersion of incident light into first-order diffracted beams having target wavelengths and transmit the first-order diffracted beams into the optical substrate, and wherein a diffraction angle of each of the first-order diffracted beams having the target wavelengths is smaller than a total reflection angle between the optical substrate and air. The light outlet layer is configured to extract the first-order diffracted beams having the target wavelengths in the optical substrate.

Techniques for hyperspectral imaging, including a device for hyperspectral imaging including at least one tunable interferometer including a thin layer of material disposed between two or more broadband mirrors. Electrodes placed on either side of the tunable interferometer can be coupled to a voltage control circuit, and upon application of a voltage across the tunable interferometer, the distance between the mirrors can be modulated by physically altering the dimensions of the thin layer of material, which can uniformly load the broadband mirrors. Physically altering the dimensions of the thin layer of material can include one or more of deformation of a soft material, piezostrictrive actuation of a piezostrictrive material, or electrostrictive actuation of an electrostrictive material.

Apparatus for spectrometrically capturing light includes a wavelength-adjustable filter for converting spectral information into location information and an organic photodiode for converting the location information into electrical signals which can be forwarded, wherein the filter and the organic photodiode form a one-piece monolith, the organic photodiode is connected to the filter or the organic photodiode is integrated in the filter, the filter consists of at least one spectrally resolving element in the form of at least one layer-like photonic crystal which constitutes the monolith and in which two layers of variable thickness D are formed along a direction perpendicular to the incidence of light. A resonant layer is arranged between the two layers. The organic photodiode includes: a photoactive layer, a first electrode, and a second electrode sandwiching the photoactive layer, and one of the electrodes is in contact with the photonic crystal.

Disclosed is an optical sensor, including an external cavity laser configured to output sensing light and reference light; and a photodetector configured to detect a beating signal by an interference of the sensing light and the reference light output from the external cavity laser, in which the external cavity laser includes a reflecting filter including a sensing grating, to which a sensing object is attachable, and a reference grating, which is disposed on the same plane as that of the sensing grating, and outputs sensing light reflected from the sensing grating and reference light reflected from the reference grating. Accordingly, the optical sensor does not require a high-resolution spectroscope and has improved resolution and sensitivity.

An electromagnetic radiation detector includes an InP substrate having a first surface opposite a second surface; a first InGaAs electromagnetic radiation absorber stacked on the first surface and configured to absorb a first set of electromagnetic radiation wavelengths; a set of one or more buffer layers stacked on the first InGaAs electromagnetic radiation absorber and configured to absorb at least some of the first set of electromagnetic radiation wavelengths; a second InGaAs electromagnetic radiation absorber stacked on the set of one or more buffer layers and configured to absorb a second set of electromagnetic radiation wavelengths; and an immersion condenser lens formed on the second surface and configured to direct electromagnetic radiation through the InP substrate and toward the first InGaAs electromagnetic radiation absorber and the second InGaAs electromagnetic radiation absorber.

Novel monolithic cyclical reflective spatial heterodyne spectrometers (CRSHS) are presented. Monolithic CRSHS in accordance with the invention have a single frame wherein a flat mirror, roof mirror, and symmetric grating are affixed. The invention contains only fixed parts; the flat mirror, roof mirror, and symmetric grating do not move in relation to the frame. Compared to conventional CRSHS known in the art, the present invention enables much smaller and lighter CRSHS, requires less time and skill for maintenance, and is a better economic option. The disclosed invention may include fixed field-widening optical elements or a fiber-fed assembly.

A spectral camera for producing a spectral output is disclosed. The spectral camera has an objective lens for producing an image, an optical duplicator, an array of filters, and a sensor array arranged to detect the filtered image copies simultaneously on different parts of the sensor array. Further, a field stop defines an outline of the image copies projected on the sensor array. The filters are integrated on the sensor array, which has a planar structure without perpendicular physical barriers for preventing cross talk between each of the adjacent optical channels. The field stop enables adjacent image copies to fit together without gaps for such barriers. The integrated filters mean there is no parasitic cavity causing crosstalk between the adjacent image copies. This means there is no longer a need for barriers between adjacent projected image copies, and thus sensor area can be better utilized.

The arrangement comprises a filter region (10) filtering electromagnetic radiation and a shielding component (20) inhibiting propagation of electromagnetic radiation. The filter region comprises a central filter region (11) and a separate peripheral filter region (13). The shielding component comprises an aperture (21). The aperture is arranged above the central filter region. The central filter region and the peripheral filter region are optimized for different angles of incidence (α, β) and provided for measurements by individual sensor regions (18, 19).

A liquid-crystal based color switch for use with an image sensor having sub-diffraction-limited (SDL) pixels. The color switch may switch between a first mode where green light is passed (and blue and red light is blocked) and a second mode where blue and red light is passed (and green light is blocked). The color switch may include an achromatic switch (such as a liquid crystal switch) and retarder stack filter that are both sandwiched between a first and a second polarizer. The SDL pixels may be distributed so that green subpixels are never adjacent to other green subpixels in the same row or column, so that red subpixels are always adjacent to green subpixels in the same row or column, and so that blue subpixels are always adjacent to green subpixels in the same row or column.

A variable wavelength optical filter module according to the present invention includes a package, a variable wavelength optical filter, and a detector. The package includes a reflection part (reflecting faces) in the inside of the package. The variable wavelength optical filter is disposed in the inside of the package and includes a first reflecting plate and a second reflecting plate facing each other, with a clearance between the first reflecting plate and the second reflecting plate being variable. The detector is disposed in the inside of the package and detects a ray of light having passed through the variable wavelength optical filter. Then, the variable wavelength optical filter and the detector are disposed on the opposite side to the reflection part (reflecting faces). The ray of the light incident into the inside of the package via the variable wavelength optical filter enters the detector via the reflection part (reflecting faces).