We disclose an on-chip photonic spectroscopy system capable of dramatically improving the signal-to-noise ratio (SNR), dynamic range, and reconstruction quality of Fourier transform spectrometers. Secondly, we disclose a system of components that makes up a complete on-chip RF spectrum analyzer with low-cost and high-performance.

An optical characteristics measuring method for measuring optical characteristics of a subject, the optical characteristics measuring method including: a step of acquiring one or more captured images including the subject, using an image capturing apparatus that is located at a predetermined distance from the subject, and is configured to be displaceable relative to the subject, while maintaining the predetermined distance; and a step of creating, based on the one or more captured images thus acquired, a virtual image including the subject and acquired from one or more analysis points each located at a position other than a position on a plane that includes the trajectory of the image capturing apparatus.

A light detection device includes: a Fabry-Perot interference filter provided with a light transmission region; a light detector configured to detect light transmitted through the light transmission region; a package having an opening and accommodating the Fabry-Perot interference filter and the light detector, and a light transmitting unit arranged on an inner surface of the package so as to close an opening, the light transmitting unit including a band pass filter configured to transmit light incident on the light transmission region. When viewed from a direction parallel to the line, an outer edge of the Fabry-Pert interference filter is positioned outside an outer edge of the opening, and an outer edge of the light transmitting unit is positioned outside the outer edge of the Fabry-Perot interference filter.

An embodiment of a laser induced breakdown system is described that comprises a portable device that includes: a laser configured to produce a beam comprising a plurality of repeating pulses; a processor configured to open a data acquisition window after a delay period, wherein the delay period begins upon production of one of the pulses; one or more optical elements configured to direct the beam at a sample and collect emitted light from a plasma continuum; and an optical detector configured to produce a plurality of signal values from the emitted light from the plasma continuum collected during the data acquisition window, wherein the processor is configured to identify an element from the signal values.

A terahertz wave spectroscopic measurement device includes a light source that emits a terahertz wave and probe light having a wavelength different from that of the terahertz wave, an internal total reflection prism including an incidence surface of the terahertz wave, a placement surface on which a measurement target is placed, and an emission surface of the terahertz wave, the internal total reflection prism internally totally reflecting the terahertz wave incident from the incidence surface by means of the placement surface and emitting the terahertz wave from the emission surface, and a terahertz wave detection unit that indirectly detects the terahertz wave emitted from the emission surface using the probe light. The internal total reflection prism includes an avoidance portion on which incidence of the probe light on the measurement target on the placement surface is avoided.

A light detection device includes: a Fabry-Perot interference filter provided with a light transmission region; a light detector configured to detect light transmitted through the light transmission region; a package having an opening and accommodating the Fabry-Perot interference filter and the light detector; and a light transmitting unit arranged on an inner surface of the package so as to close an opening, the light transmitting unit including a band pass filter configured to transmit light incident on the light transmission region. When viewed from a direction parallel to the line, an outer edge of the Fabry-Perot interference filter is positioned outside an outer edge of the opening, and an outer edge of the light transmitting unit is positioned outside the outer edge of the Fabry-Perot interference filter.

A light detection device includes: a Fabry-Perot interference filter provided with a light transmission region; a light detector configured to detect light transmitted through the light transmission region; a package having an opening and accommodating the Fabry-Perot interference filter and the light detector; and a light transmitting unit arranged on an inner surface of the package so as to close an opening, the light transmitting unit including a band pass filter configured to transmit light incident on the light transmission region. When viewed from a direction parallel to the line, an outer edge of the Fabry-Perot interference filter is positioned outside an outer edge of the opening, and an outer edge of the light transmitting unit is positioned outside the outer edge of the Fabry-Perot interference filter.

Filter wheel assemblies with a single actuation point to control positioning of front and rear optical filter elements simultaneously and to provide high channel density with a plurality of selectable optical filter pairs. A filter wheel assembly may include a plurality of optical filter element pairs arranged around a common axis, wherein each of the plurality of optical filter element pairs includes a first filter element and a complementary filter element, wherein each first filter element and each complementary filter element has a surface having a normal component directed toward an inner portion of the filter wheel assembly.

A direct absolute spectrometer includes: a first light source; a second light source; an optical combiner that produces dual light; an optical cell that receives the dual light; an electromagnetically induced transparent medium that is optically transparent to single photon light in a presence of pump light, such that output light is produced; and a filter that filters output light and provides EIT light free from, wherein electromagnetically induced transparent EIT light is a direct and absolute metric of a linewidth and a wavelength of single photon light such that the direct absolute spectrometer provides direct and absolute determination of the linewidth of the single photon light and direct and absolute determination of wavelength at a maximum of intensity of the single photon light.

An infrared (IR) imaging system for determining a concentration of a target species in an object is disclosed. The imaging system can include an optical system including a focal plane array (FPA) unit behind an optical window. The optical system can have components defining at least two optical channels thereof, said at least two optical channels being spatially and spectrally different from one another. Each of the at least two optical channels can be positioned to transfer IR radiation incident on the optical system towards the optical FPA. The system can include a processing unit containing a processor that can be configured to acquire multispectral optical data representing said target species from the IR radiation received at the optical FPA. One or more of the optical channels may be used in detecting objects on or near the optical window, to avoid false detections of said target species.