A system and method for internally inspecting a tubular composite part so as to identify and measure adhesive flow therewithin are provided, along with an endpoint adapter assembly of a near infrared (NIR) spectrometer. The system includes an end point adapter that fits within and maintains a consistent cross-sectional position within the tubular composite part. The system also includes a plurality of optical fibers extending radially outward from the end point adapter. The end point adapter moves longitudinally through the tubular composite part and receives light with the plurality of optical fibers following interaction of the light with the tubular composite part. The system further includes a NIR imaging spectrometer configured to disperse the light being collected by the plurality of optical fibers across an NIR spectrum and a NIR camera configured to generate images of the tubular composite part based on dispersed light.

A spectrograph as disclosed includes a housing, wherein a wall of the housing includes first, second and third openings, an entrance slit located at the first opening and configured to direct light along a first light path portion in the interior of the housing, a dispersive element located at the second opening and configured to receive light from the entrance slit along the first light path portion and direct light along a second light path portion in the interior of the housing, a detector located at the third opening and configured to receive light from the dispersive element along the second light path portion. The detector can include first and second groups of light-sensitive regions. A cover can be positioned to separate the first group of light-sensitive regions from the light path, the second group of light-sensitive regions being exposed to the light path.

The invention provides methods and apparatus comprising a multi-wavelength laser source that uses a single unfocused pulse of a low intensity but high power laser over a large sample area to collect Raman scattered collimated light, which is then Rayleigh filtered and focused using a singlet lens into a stacked fiber bundle connected to a customized spectrograph, which separates the individual spectra from the scattered wavelengths using a hybrid diffraction grating for collection onto spectra-specific sections of an array photodetector to measure spectral intensity and thereby identify one or more compounds in the sample.

Microstructured optical fiber (MOF) includes a cladding extending a length between first and second ends. The cladding includes an inner porous microstructure that at least partially surrounds a hollow core. A perimeter contour of the hollow core has a non-uniform radial distance from a center axis of the cladding such that first segments of the cladding along the perimeter contour have a shorter radial distance from the center axis relative to second segments of the cladding along the perimeter contour. The cladding receives and propagates light energy through the hollow core, and the inner porous microstructure substantially confines the light energy within the hollow core. The cladding defines at least one port hole that extends radially from an exterior surface of the cladding to the hollow core. Each port hole penetrates the perimeter contour of the hollow core through one of the second segments of the cladding.

A connector assembly is provided for coupling optical fibers to a spectrometer. The connector assembly includes a plate having a slit defined therein and a ferrule that secures end portions of the optical fibers therein. The ferrule includes a forward end having an aperture that receives the optical fibers. The connector assembly further includes a connector housing having an alignment mechanism with a plate recess dimensioned to receive the plate therein and a ferrule recess dimensioned to receive the forward end of the ferrule therein. The plate recess orients the plate and the ferrule recess orients the ferrule within the connector assembly that includes a spring for imparting a force urging the forward end of the ferrule into contact with the plate to minimize an air gap between the plate and the ferrule. The spring and the alignment mechanism maintain the ferrule in an x-y-z, rotation, and/or an angular orientation.

Disclosed is an apparatus for optical emission spectroscopy which includes a light measuring unit measuring light in a process chamber performing a plasma process on a substrate, a light analyzing unit receiving light collected from the light measuring unit to analyze a plasma state, a control unit receiving an output signal of the light analyzing unit to process the output signal, and a light collecting controller disposed between the process chamber and the light measuring unit so as to be combined with the light measuring unit. The light collecting controller controls the light collected to the light measuring unit.

A connector assembly is provided for coupling optical fibers to a spectrometer. The connector assembly includes a plate having a slit defined therein and a ferrule that secures end portions of the optical fibers therein. The ferrule includes a forward end having an aperture that receives the optical fibers. The connector assembly further includes a connector housing having an alignment mechanism with a plate recess dimensioned to receive the plate therein and a ferrule recess dimensioned to receive the forward end of the ferrule therein. The plate recess orients the plate and the ferrule recess orients the ferrule within the connector assembly that includes a spring for imparting a force urging the forward end of the ferrule into contact with the plate to minimize an air gap between the plate and the ferrule. The spring and the alignment mechanism maintain the ferrule in an x-y-z, rotation, and/or an angular orientation.

Microstructured optical fiber (MOF) includes a cladding extending a length between first and second ends. The cladding includes an inner porous microstructure that at least partially surrounds a hollow core. A perimeter contour of the hollow core has a non-uniform radial distance from a center axis of the cladding such that first segments of the cladding along the perimeter contour have a shorter radial distance from the center axis relative to second segments of the cladding along the perimeter contour. The cladding receives and propagates light energy through the hollow core, and the inner porous microstructure substantially confines the light energy within the hollow core. The cladding defines at least one port hole that extends radially from an exterior surface of the cladding to the hollow core. Each port hole penetrates the perimeter contour of the hollow core through one of the second segments of the cladding.

A fiber optic probe assembly is provided. The probe comprises a first optical system and a second optical system, a delivery light guide comprising one or more than one delivery optical fiber for transmitting excitation radiation from a radiation source disposed at a proximal end of the light guide to the first optical system. The first optical system comprising one or more than one first optical element for forming a substantially collimated illumination beam from the excitation radiation. An optically opaque tubular sleeve is fitted over the first optical system to optically isolate the first optical system and the delivery light guide from the second optical system. The second optical system comprising one or more than one second optical element for gathering optical radiation scattered from a sample and forming the optical radiation into a collection beam. A collection light guide comprising one or more than one collection optical fiber receives the collection beam and transmits the collection beam to an analyzer. The first and second optical systems are disposed within a housing so that an emission cone of the first optical system and an acceptance cone of the second optical system substantially overlap. A spectroscopic measurement system comprising the optic fiber probe is also provided.

The present invention provides a spectral apparatus for spectrally separating light including a predetermined wavelength, including a slit that the light enters, a first optical system configured to collimate the light from the slit, a transmissive type diffraction element configured to diffract the light from the first optical system, and a second optical system including a first mirror configured to reflect the light diffracted by the transmissive type diffraction element, and a second mirror configured to reflect the light reflected by the first mirror and diffracted by the transmissive type diffraction element, and configured to make the light reciprocally travel between the first mirror and the second mirror via the transmissive type diffraction element.