Abstract:
An exemplary embodiment includes an apparatus having an energy source for selectively directing a first energy toward a first material. The at least a portion of the first energy excites a preselected second material to an excited state where at least two photons of the first energy are absorbed by the molecule of the second material causing the molecule to emit a second energy at about a predetermined wavelength. The apparatus also includes a control system for directing the first energy toward the first material. The apparatus also includes a detector for detecting at least a portion of the emitted second energy when the detector is more than about 40 meters from the molecule.
Abstract:
An illumination device for use with a product inspection machine inspecting products according to at least one characteristic. The invention also pertains to an illumination device for use in sorting machines that optically sort or separate nonstandard fungible objects from standard objects as they pass a viewing station by viewing such objects illuminated by at least one wavelength. The invention includes a plurality of arrays of semiconductor light sources impinging on passing product and at least one array of semiconductor light sources of wavelength and intensity equal to the plurality of arrays impinging on a background surface for detection and comparison.
Abstract:
In a spectrometer, preferably in a spectrometric microscope, input light is provided from a light source to a specimen via a source objective element (e.g., a Schwarzchild objective), and the aperture of the light source is matched to the aperture of the source objective element to maximize light throughput to the specimen. The light from the specimen is then collected at a collector objective element and delivered to a camera element, which in turn provides the light to a photosensitive detector. The apertures of the camera element and the collector objective element are also matched to maximize light throughput from the specimen to the detector. As a result, light loss from vignetting effects is reduced, improving the intensity and uniformity of illumination and the sensitivity and accuracy of spectral measurements.
Abstract:
In a spectrometer, preferably in a spectrometric microscope, light from a specimen is collected at a collector objective element and delivered to a camera element, which in turn provides the light to a photosensitive detector. A focal plane is provided between the collector objective element and the camera element, and one or more aperture arrays may be situated in the focal plane to restrict the detector's field of view of the specimen to the areas within the apertures. By utilizing aperture arrays with apertures of different sizes and shapes, the spatial resolution of the spectrometer readings may be varied without the need to vary the optics of the spectrometer. As a result, if the optics are optimized to minimize vignetting, spatial resolution may be varied without adverse increases in vignetting.
Abstract:
A spectroscopy system is provided which is optimized for operation in the VUV region and capable of performing well in the DUV-NIR region. Additionally, the system incorporates an optical module which presents selectable sources and detectors optimized for use in the VUV and DUV-NIR. As well, the optical module provides common delivery and collection optics to enable measurements in both spectral regions to be collected using similar spot properties. The module also provides a means of quickly referencing measured data so as to ensure that highly repeatable results are achieved. The module further provides a controlled environment between the VUV source, sample chamber and VUV detector which acts to limit in a repeatable manner the absorption of VUV photons. The use of broad band data sets which encompass VUV wavelengths, in addition to the DUV-NIR wavelengths enables a greater variety of materials to be meaningfully characterized. Array based detection instrumentation may be exploited to permit the simultaneous collection of larger wavelength regions.
Abstract:
A spectral encoder for producing spectrally selected images of a radiation field containing multiple spectral components. An imaging spectrograph defines a first optical path that produces from the input radiation field a spectrally dispersed image comprising multiple spectral components displaced along a dispersion direction. Spectral pass bands are encoded on the dispersed image by a programmable spatial light modulator using one or more spatial masks. The imaging spectrograph further defines a second optical path that reverses the spectral dispersion of the first path and produces a spectrally-encoded polychromatic output image containing only those spectral components encoded by the spatial mask. The first and second optical paths share a common dispersing element. A detector records at least one spatial region of the spectrally encoded output image.
Abstract:
A spectroscopic method and system for the spectral analysis of an optical signal directed to a wavelength dispersive component having two interleaved dispersive devices. For a single wavelength, the optical signal exiting the interleaved dispersive devices includes two wavefronts generally disposed at an angle to one another and producing an interference pattern. The interference pattern is detected and subsequently analyzed via a Fourier transform to produce the optical spectrum of the input beam. The method and system are applicable in a planar waveguide environment, in reflection and transmission geometries.
Abstract:
A spectral encoder for producing spectrally selected images of a radiation field containing multiple spectral components. An imaging spectrograph defines a first optical path that produces from the input radiation field a spectrally dispersed image comprising multiple spectral components displaced along a dispersion direction. Spectral pass bands are encoded on the dispersed image by a programmable spatial light modulator using one or more spatial masks. The imaging spectrograph further defines a second optical path that reverses the spectral dispersion of the first path and produces a spectrally-encoded polychromatic output image containing only those spectral components encoded by the spatial mask. The first and second optical paths share a common dispersing element. A detector records at least one spatial region of the spectrally encoded output image.
Abstract:
An optical spectrum analyzer is implemented with a detector combined with a tunable filter mounted on a stage capable of 360-degree rotation at a constant velocity. Because of the constant rate of angular change, different portions of the input spectrum are detected at each increment of time as a function of filter position, which can be easily measured with an encoder for synchronization purposes. The unidirectional motion of the mirror permits operation at very high speeds with great mechanical reliability. The same improvements may be obtained using a diffraction grating or a prism, in which case the detector or an intervening mirror may be rotated instead of the grating or prism.
Abstract:
In preferred forms of the invention an array of MEMS mirrors or small mirrors inside an optical system operates closed-loop. These mirrors direct external source light, or internally generated light, onto an object—and detect light reflected from it onto a detector that senses the source. Local sensors measure mirror angles relative to the system. Sensor and detector outputs yield source location relative to the system. One preferred mode drives the MEMS mirrors, and field of view seen by the detector, in a raster, collecting a 2-D or 3-D image of the scanned region. Energy reaching the detector can be utilized to analyze object characteristics, or with an optional active distance-detecting module create 2- or 3-D images, based on the object's reflection of light back to the system. In some applications, a response can be generated. The invention can detect sources and locations for various applications.