Abstract:
A long wave infrared imaging polarimeter (LWIP) is disclosed including a pixilated polarizing array (PPA) in close proximity to a microbolometer focal plane array (MFPA), along with an alignment engine for aligning and bonding the PPA and MFPA and method for assembly.
Abstract:
The invention concerns a tandem interferometer for temperature sensing. The low coherence interferometry (LCI) system comprises a polarization-based sensing interferometer comprising a birefringent crystal having a sensor temperature sensitivity and a birefringence dispersion, and a readout interferometer being either a Fizeau interferometer using an optical wedge or a polarization interferometer using a birefringent wedge. In one embodiment of the invention, the birefringent crystal has dispersion properties similar to that of the birefringent wedge or that of the optical wedge of the readout interferometer. The present invention also provides a signal processing method for correcting the dispersion effect and for noise filtering in LCI-based optical sensors of the tandem interferometer arrangement.
Abstract:
A method and apparatus for measurement of the brightness, flow velocity and temperature of radiant media. A substantially collimated beam (3) of light is directed to a linear polarizer (5) through an interference filter (4). An electro-optically active birefringent crystal (7) separates the linearly polarized output of the polarizer (5) into two characteristic waves and introduces a final phase delay between the wave. The birefringent crystal (7) is electro-optically modulated to introduce a variable phase delay between the characteristic waves. The resultant characteristic waves are combined to interfere and the combination is sampled to produce a signal from which the emission moment of the radiant media can be determined.
Abstract:
A method and apparatus for measurement of the brightness, flow velocity and temperature of radiant media. A substantially collimated beam (3) of light is directed to a linear polarizer (5) through an interference filter (4). An electro-optically active birefringent crystal (7) separates the linearly polarized output of the polarizer (5) into two characteristic waves and introduces a final phase delay between the wave. The birefringent crystal (7) is electro-optically modulated to introduce a variable phase delay between the characteristic waves. The resultant characteristic waves are combined to interfere and the combination is sampled to produce a signal from which the emission moment of the radiant media can be determined.
Abstract:
A long wave infrared imaging polarimeter (LWIP) is disclosed including a pixilated polarizing array (PPA) in close proximity to a microbolometer focal plane array (MFPA), along with an alignment engine for aligning and bonding the PPA and MFPA and method for assembly.
Abstract:
An infrared detection device, e.g. for the 8 to 14 micrometre waveband, comprises a Langmuir-Blodgett or other very thin film (10) having pyroelectric or other temperature-dependent characteristics. At least one detector element having opposite electrical conductors (21 and 22) is formed in the film (10). The film (10) which may have a support layer (15) is mostly free of contact with a mount arrangement (25) which supports the film (10) in a very low thermally-conductive manner. In accordance with the present invention, the film (10) is very thin, but very efficient absorption of the radiation (31) is obtained in the following manner: the facing surface (26) of the mount arrangement (25) is reflective for the radiation (31); the sum of the optical thicknesses (n.t) of the film (10), (N.T) of any support layer (15) and (d) of a gap (28) forming the multiple layer detector-element structure along the radiation path to the reflector (26) is approximately one quarter of a selected wavelength (e.g. 9.6 micrometres) in the range to be detected; and the conductors (21 and 22) each comprise a resistive layer providing a sufficient resistance per square (Z1 and Z2, e.g. of twice the characteristic impedance of free space) as to absorb a substantial proportion of the incident radiation (31) and reflected radiation (32) in the wavelength range. Spaced supporting elements (252) below the film (10) can support the film (10) over the reflector (26) with a well-defined small gap (28) and carry an electrical connection to the second conductor(s) (22) below the film.
Abstract:
PROBLEM TO BE SOLVED: To provide a method and an apparatus for measuring the temperature of sheet steel suitable for performing online and continuous measurements on the surface temperature of sheet steel heat-treated in an annealing furnace. SOLUTION: A heat-resisting material having a high emissivity in the infrared wavelength region is embedded in part of a furnace wall of the heating furnace. Radiances of a plurality of wavelengths in directions of regular reflection of radiant light from the heat-resisting material at the surface of the sheet steel are measured in each of a plurality of polarization angle components. The emissivity of the sheet steel is computed on the basis of signals of measured radiance each in the plurality of polarization angle components in the plurality of wavelengths and the surface temperature of the heat-resisting material. The surface temperature of the sheet steel is computed on the basis of this emissivity. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
A short wave infrared polarimeter comprising a pixelated polarizer array and an Indium-Gallium-Arsenide (“InGaAs”) focal plane array. The short wave infrared polarimeter optionally includes a micro-lens array and/or an aperture layer.
Abstract:
A long wave infrared imaging polarimeter (LWIP) is disclosed including a pixilated polarizing array (PPA) in close proximity to a microbolometer focal plane array (MFPA), along with an alignment engine for aligning and bonding the PPA and MFPA and method for assembly.