Abstract:
A holographic imaging system is disclosed that includes a spectral electromagnetic field unit for providing a plurality of focal areas of a plurality of wavelengths of electromagnetic fields along a first direction, a lens system for directing the electromagnetic fields having the plurality of wavelengths from an object that may be positioned at least substantially near the plurality of focal areas toward a holographic recording, and a detector surface for receiving electromagnetic fields from the holographic recording.
Abstract:
A direct-view handheld binocular spectrometer for use in a variety of educational settings. The device comprises a holographic transmission diffraction grating and a uniquely curved quantitative wavelength scale for viewing visible-wavelength spectra with both eyes simultaneously. A variable width entrance slit, adjustable illumination for the wavelength scale, and attachable corrective lenses enhance the ease of use and efficiency as compared to traditional monocular spectrometers.
Abstract:
One embodiment of a system includes a sophisticated volume hologram for dispersing an incident optical signal with uniform spectrum over an input plane to an output pattern with non-uniform spatial-spectral information, where the sophisticated volume hologram includes a plurality of holograms that map different input wavelengths into a diverse spatial pattern. The system further includes a detector for receiving and detecting light dispersed by the sophisticated volume hologram. Other systems and methods are also provided.
Abstract:
A field multiplexed dispersive imaging spectrometer (20). The novel system includes foreoptics (22) for receiving incoming electromagnetic energy, a disperser (24) disposed to receive energy from the foreoptics (22), and a focal plane array (28) disposed to receive energy from the disperser (24). The disperser (24) is a computer generated holographic disperser designed to disperse light into several, overlapping diffraction orders. In the preferred embodiment, the disperser (24) is designed with greater energy in the central, undiffracted order than in the other diffracted orders. The system (20) also includes a processor (30) which takes the data detected by the focal plane array (28) and generates a representation of the input image in several color bands using an iterative restoration algorithm (32).
Abstract:
Systems and methods for rapid Raman spectroscopy. The speed is improved by providing light from a sample to a light-dispersive element, such as a holographic grating, in a pattern that inversely complements distortion caused by the grating. For example, if the grating imparts a curve to the spectral lines emanating from the grating, then the light is inserted into the grating in a curve in the opposite direction. Also calibration light guides able to transmit a known, or standard, light to the detection or spectroscopy system. The calibration light guide can be useful both with traditional light transmission guides and with the light transmission guides of the present invention.
Abstract:
A spectrometer has higher resolving power without enlarging a size of the apparatus. This spectrometer has a slit board, a mirror, a collimator lens, a holographic grating, an Echelle grating, a magnifier lens and a line sensor. The holographic grating is arranged to diffract parallel light incident from the collimator lens toward the Echelle grating. The Echelle grating is arranged to reflect the parallel light incident from the holographic grating toward the holographic grating.
Abstract:
A system for automatic color calibration for a color display is provided having an assembly of a member adjacent the outer periphery of the screen of the display and a color measuring instrument coupled to the member. The system is particularly usefull at a site or node of a network of sites or nodes for distributing and controlling color reproduction. The color measuring instrument includes a sensor spaced from the screen at an angle with respect to the screen for receiving light from an area of the screen. Methods are also provided for maintaining calibration of a color display using a color measuring instrument. Apparatuses are further provided for checking the calibration of a color measurement instrument having a spectrograph for measuring color.
Abstract:
A spectrum analyzer providing an integrated calibration function and for providing that calibration function automatically. The injection of light to be analyzed through a central aperture of a scanning grating onto a focusing reflector provides in combination four traversals of the space therebetween. The spectrometer thus is used to separate wavelength information spacially and receive it back at the same or adjacent aperture(s) to be analyzed by a processing system to establish the spectra for the incident light. The light is typically injected from and received back into optical fibers or other light carrying elements. Calibration light is also applied through the same or adjacent apertures in the grating from a known source and spectra such as Argon to use as a calibration reference by detecting the known spectra peaks and correlating it to grating scan angle. The same structure is also used as a telecommunications channel router by injecting light of multi-channel and thus broadband spectral content into the spectrometer through the central aperture(s) and angling the grating so that a selected channel or channels are reflected back after four passages of the spectral separator to output one or more optical fibers or other guides.
Abstract:
This invention comprises a novel apparatus for recording a holographic groove pattern on a diffraction grating blank. The recording apparatus is configured using newly developed groups of analytical equations. The invention further comprises the novel holographic diffraction grating made with the inventive recording apparatus. The invention additionally comprises monochromators and spectrometers equipped with the inventive holographic diffraction grating. Further, the invention comprises a monochromator configured to reduce aberrations using a newly developed group of analytical equations. Additionally, the invention comprises a method to reduce aberrations in monochromators and spectrometers using newly developed groups of analytical equations.
Abstract:
A reflectometer for measuring absorption of light in selected regions of the light spectrum by a diffuse reflector. The reflectometer is adapted to precisely measure absorption resulting from the constituents present in body fluids. The sample to be measured is illuminated by a focussed light source at an angle of 45.degree. to its surface. The light diffusely reflected about the normal to the sample falls on a small round bundle of optical fibers. At the opposite end of the bundle, the fibers are arranged into a narrow rectangle. This rectangle forms the entrance slit for a concave holographic diffraction grating. The grating forms images of this entrance slit spectrally separated over a flat field suitable for recording the spectrum on film or on an array of discrete detectors.