Abstract: A system or method for analyzing a sample include an input light source, a double subtractive monochromator positioned to receive light from the input light source and to sequentially illuminate the sample with each of a plurality of wavelengths, a multi-channel fluorescence detector positioned to receive and substantially simultaneously detect multiple wavelengths of light emitted by the sample for each of the plurality of excitation wavelengths, an absorption detector positioned to receive and detect light passing through the sample, and a computer in communication with the monochromator, the fluorescence detector, and the absorption detector, the computer controlling the monochromator to sequentially illuminate the sample with each of the plurality of wavelengths while measuring absorption and fluorescence of the sample based on signals received from the fluorescence and absorption detectors

Abstract: A spectrometer which in one embodiment including a dispersive element and a concave element. The dispersive element may be a flat or concave grating which receives light and reflects the light in different collimated wavelengths. The concave element being located downstream from the dispersive element and arranged to reflect and focus the light toward a detector. The reflected light from the concave element including astigmatism. A cylindrical lens positioned between the concave element and the detector and configured to simultaneously correct the astigmatism and demagnify the light across the detector. In one embodiment the cylindrical lens varies in thickness progressively along its length.

Abstract: A method of spectrographic measurement is disclosed. The method generates light energy using a solid state low capacitance excitation source, the light energy being caused to fall on a sample to be assayed, causing the sample to output an output optical signal. The method generates a plurality of modulation frequencies, and a plurality of heterodyne frequencies to form a set of heterodyne signals at the heterodyne frequencies. Each of the heterodyne frequencies is associated with one of the modulation frequencies. Coupling the modulation frequencies to the excitation source, causes the excitation source to generate excitation energy modulated in intensity in proportion to the modulation frequencies. A sampling a portion of the substantially incoherent excitation energy forms a reference substantially incoherent excitation signal.

Abstract: A method for identification of a sample of a material is disclosed. The method includes illuminating a sample at a plurality of excitation wavelengths, measuring the intensity at each of the plurality of excitation wavelengths, locating the values of maxima in the three-dimensional intensity contour, comparing the maxima to a library of values of known maxima associated with known species, generating a model of a three-dimensional intensity contour based on maxima values comprising values of likely maxima from the library, comparing the model of an intensity contour to the measured contour to determine residual errors, outputting the species associated with the maxima values used to generate the model as an indicator of species, determining corrections to the model of a three-dimensional intensity contour to generate a corrected model, and returning to the comparison step to test the corrected model.

Abstract: The invention concerns a Raman spectrometry apparatus containing a source of excitation (14), optical means (16) of excitation directing a beam of excitation (15) derived from that source on the sample (17), means (18) for collecting the energy diffused by the sample (17) containing an inlet diffusion slot (19), a spectral dispersion system (20), means for selecting the Raman energy (23), a detector (22), optical detection means (21) directing the Raman energy thus collected and selected to the detector (22). According to the invention, the optical means (16) of excitation cause the beam of excitation (15) to be dispersed by the dispersion system (20), said optical means (16) of excitation containing an inlet slot (24) and an outlet slot of excitation constituted by the inlet diffusion slot (19) and selecting the wavelength of excitation.

Abstract: An optical imager, such as a microscope for performing multiple frequency fluorometric measurements comprising a light source, such as a laser source is disclosed. The system is used to excite a sample into the fluorescent state. Light from the excited sample is collected by a microscope. The microscope utilizes conventional confocal optics optimized to have a very narrow depth of field, thus limiting the information collected to a thin planar region. Measurements are taken over the fluorescence lifetime of the sample simultaneously from the excitation source and from the excited sample. Information is taken in a matrix and comparison of the image matrix and the standard during simultaneous measurements yields output information.

Abstract: A spectrograph with a first concave spectrographic diffraction grating is positioned to receive light from an input light source. The first concave spectrographic diffraction grating is configured to provide a diffracted light output dispersing the components of the input light source in a first dispersion direction with a first angular orientation with respect to the plane of the grating. The dispersion forms the input light into an intermediate spectrum. The intermediate spectrum is formed in a focal surface by the once diffracted light. A slit is substantially positioned on the focal surface. A second concave diffraction grating is positioned to receive once diffracted light from the slit and configured to provide a twice diffracted light output, the second concave diffraction grating dispersing the components of the input light source in a second diffraction direction with a second angular orientation with respect to the plane of the grating.

Abstract: Disclosed is an achromatic spectroscopic ellispometer for analyzing small regions of a sample over a wide range of wavelengths from ultraviolet (UV) to infrared (IR). The spectroscopic ellipsometer contains a light source emitting a light beam which passes through a polarisation state generator section before being focused at an incidence angle q by a first parabolic mirror to a small spot on a sample. A second parabolic mirror collects the reflected beam and connects said beam to an analyzing section. The reflected beam emerges from the analyzing section and is spectroscopically detected and analyzed. The light beam through the polarisation state generator section up to the first parabolic mirror and the light beam from the second mirror through the analyzing section are parallel enabling achromatism. The incidence angle q is largely varied without shifting of the location of the small spot on the sample surface.

Abstract: A forensic light source uses a pair of filter wheels to achieve a combination of the characteristics of filters on different wheels and may include a housing which supports the light, filter wheels and other parts with shock absorbing members such as rubber washers or the like to achieve a shock resistant housing. A light source and a plurality of light filters are contained within the housing. The light source is powered by an external power supply, thus making the light source light weight.

Abstract: An ultraviolet imager for forensic and other purpose, e.g. for detection of fingerprints and other forensic evidence at crime scenes permits live simultaneous viewing, with live focusing adjustments, of an ultraviolet image, converted to visible light, and capture of the ultraviolet image on light sensitive film. A modified SLR camera provides film image capture and is optically coupled with a light intensifier for viewing and focusing. A preferred viewing system employs optical symmetry between the camera and the intensfier. Both the camera and the viewing system are optimized for processing ultraviolet light by employing ultraviolet transmissive lens elements and ultraviolet-reflective mirrors throughout.

Abstract: A Littrow-type spectrometer or monochromator using a folded light path to provide a compact optical instrument is disclosed. Light enters the instrument through an inlet aperture on a planar mirror. The aperture is located at the focus of a parabolic collimator mirror. Collimated light reflected by the parabolic mirror is reflected back to the planar mirror, which is positioned at an angle to the collimated light. The light reflected from the planar mirror is directed at a planar grating that produces diffracted light having all the wavelengths input into the system, including light of a selected wavelength, back towards the planar mirror. Light having the selected wavelength is thus caused to fall on the parabolic mirror. The parabolic mirror then focuses the selected wavelength of light onto a light exit aperture that is juxtaposed to the inlet light aperture. The planar grating can be rotatably mounted to scan the input light spectrum.

Abstract: Spectrofluorometer employing a pair of linear variable spectral filters to produce a three dimensional data output is disclosed. A collimated white light source is used that first passes through a first linear variable spectral filter, then through a sample where fluorescence occurs, then the resultant light passes through a second linear variable spectral light filter that is oriented at ninety degrees from the first filter. The light is then detected by a CCD sensor for conversion into data. This arrangement provides a very simple, rugged and compact instrument that can be used almost anywhere, such as at the scene of a contamination accident.

Abstract: A UV-Imager system includes a camera. The camera includes a first UV coated mirror and a quartz UV transmittive camera lens. The UV-Imager system also includes a second UV coated mirror coupled to the camera, and an intensifier coupled to the second UV coated mirror.

Abstract: Spectrofluorometer employing a pair of linear variable spectral filters to produce a three dimensional data output is disclosed. A collimated white light source is used that first passes through a first linear variable spectral filter, then through a sample where fluorescence occurs, then the resultant light passes through a second linear variable spectral light filter that is oriented at ninety degrees from the first filter. The light is then detected by a CCD sensor for conversion into data. This arrangement provides a very simple, rugged and compact instrument that can be used almost anywhere, such as at the scene of a contamination accident.

Abstract: A modified concentric spectrograph for diffracting light with high stray light rejection without astigmatism is provided. The modified spectrograph includes a grating, a lens, and at least one entrance port and one exit port. The grating has a concave surface and a meridian plane with a first side and a second side. The lens has a substantially planar surface and a convex surface. Preferably, the convex and concave surfaces are substantially concentric. The ports are substantially located on different sides of the meridian plane near a focal plane of the spectrograph. The position of a focal plane may be modified using an optically transmissive triangular prism with a reflective surface, and an optically transmissive block. The position of a focal plane may further be modified with one or more optically transmissive plates. Methods for using the spectrograph are also provided.