Abstract:
A hyperspectral/multispectral imager comprising a housing is provided. At least one light source is attached to the housing. An objective lens, in an optical communication path comprising originating and terminating ends, is further attached to the housing and causes light to (i) be backscattered by the tissue of a subject at the originating end and then (ii) pass through the objective lens to a beam steering element at the terminating end of the communication path inside the housing. The beam steering element has a plurality of operating modes each of which causes the element to be in optical communication with a different optical detector in a plurality of optical detectors offset from the optical communication path. Each respective detector filter in a plurality of detector filters covers a corresponding optical detector in the plurality of optical detectors thereby filtering light received by the corresponding detector from the beam steering element.
Abstract:
A system for obtaining spectral images from polarized light comprising a polarization sensitive filter; the polarization sensitive filter being configured to receive light at at least one predetermined polarization orientation; and an achromatic waveplate operatively associated with the polarization sensitive filter; the achromatic waveplate being rotatable; whereby rotation of the achromatic waveplate enables light to enter the polarization sensitive spectral filter at at least two predetermined polarization orientations. A method comprising providing a polarization sensitive filter; the polarization sensitive filter being configured to receive light at at least one predetermined polarization orientation; providing an achromatic waveplate operatively associated with the polarization sensitive filter; the achromatic waveplate being rotatable; whereby rotation of the achromatic waveplate enables light to enter the polarization sensitive spectral filter at the at least two predetermined polarization orientations.
Abstract:
A method and a system for measuring an optical asynchronous sample signal. The system for measuring an optical asynchronous sampling signal comprises a pulsed optical source capable of emitting two optical pulse sequences with different repetition frequencies, a signal optical path, a reference optical path, and a detection device. Since the optical asynchronous sampling signal can be measured by merely using one pulsed optical source, the complexity and cost of the system are reduced. A multi-frequency optical comb system using the pulsed optical source and a method for implementing the multi-frequency optical comb are further disclosed.
Abstract:
A pseudo-active chemical imaging sensor including irradiative transient heating, temperature nonequilibrium thermal luminescence spectroscopy, differential hyperspectral imaging, and artificial neural network technologies integrated together. The sensor may be applied to the terrestrial chemical contamination problem, where the interstitial contaminant compounds of detection interest (analytes) comprise liquid chemical warfare agents, their various derivative condensed phase compounds, and other material of a life-threatening nature. The sensor measures and processes a dynamic pattern of absorptive-emissive middle infrared molecular signature spectra of subject analytes to perform its chemical imaging and standoff detection functions successfully.
Abstract:
A spectrometer for measuring a spectral signature of an object comprises fringe generating optics for use with a camera and a processor. The fringe generating optics are formed of front optics and birefringent optics. The front optics comprises a diffuser adapted to receive light from the object. The birefringent optics is adapted to receive light from the diffuser and to generate interference fringes. The camera is adapted to receive the interference fringes and the processor generates the spectral signature of the object. This spectrometer is an improved Fourier transform spectrometer suitable for use with digital cameras, such as cameras found in mobile devices.
Abstract:
A method and a system for measuring an optical asynchronous sample signal. The system for measuring an optical asynchronous sampling signal comprises a pulsed optical source capable of emitting two optical pulse sequences with different repetition frequencies, a signal optical path, a reference optical path, and a detection device. Since the optical asynchronous sampling signal can be measured by merely using one pulsed optical source, the complexity and cost of the system are reduced. A multi-frequency optical comb system using the pulsed optical source and a method for implementing the multi-frequency optical comb are further disclosed.
Abstract:
A multispectral imaging system and method in which the zero-mode channel is used to provide imaging of any of a variety of optical properties. In one example an imaging method includes spectrally dispersing received electromagnetic radiation into its spectral components with a dispersive element to produce spectrally dispersed electromagnetic radiation, transmitting the electromagnetic radiation through the dispersive element to produce non-dispersed electromagnetic radiation corresponding to a zero order diffraction mode of the dispersive element, imaging the non-dispersed electromagnetic radiation to produce a zero-mode image, and simultaneously imaging the spectrally dispersed electromagnetic radiation to produce a spectral image.
Abstract:
A hyperspectral/multispectral imager comprising a housing is provided. At least one light source is attached to the housing. An objective lens, in an optical communication path comprising originating and terminating ends, is further attached to the housing and causes light to (i) be backscattered by the tissue of a subject at the originating end and then (ii) pass through the objective lens to a beam steering element at the terminating end of the communication path inside the housing. The beam steering element has a plurality of operating modes each of which causes the element to be in optical communication with a different optical detector in a plurality of optical detectors offset from the optical communication path. Each respective detector filter in a plurality of detector filters covers a corresponding optical detector in the plurality of optical detectors thereby filtering light received by the corresponding detector from the beam steering element.
Abstract:
A single-shot real-time spectropolarimeter for use in astronomy and other sciences that captures and encodes some or all of the Stokes polarization parameters simultaneously using only static, robust optical components with no moving parts is described. The polarization information is encoded onto the spectrograph at each wavelength along the spatial dimension of the 2D output data array. The varying embodiments of the concept include both a two-Stokes implementation (in which any two of the three Stokes polarization parameters are measured) and a full Stokes implementation (in which all three of the Stokes polarization parameters are measured), each of which is provided in either single beam or dual beam forms.