Abstract:
A steerable-light-path optical device includes a light transceiver having an external light path associated therewith, and a path-steering device that controls the direction of the light path relative to a steering axis. The path-steering device has a first beam-deviation optical element including a first prism structure having a first diffraction grating thereon, and a second beam-deviation optical element including a second prism structure having a second diffraction grating thereon. The steering axis passes through the first and second beam-deviation optical elements. A rotational drive is operable to rotate at least one of the first beam-deviation optical element and the second beam-deviation optical element, and preferably both of the beam-deviation optical elements, about the steering axis.
Abstract:
A system and method for combining a predetermined number of laser beams. The system (30) includes a collimating lens (34) for receiving and collimating the laser beams and a holographic device (36) positioned to receive beams from the collimating lens (34) and output beams which are co-aligned. The holographic device (36) includes a predetermined number of holographic optical elements (46, 48, 50), wherein each holographic optical element (46, 48, 50) is designed for a particular wavelength of the laser beams. In the preferred embodiment, the holographic optical elements are volume holograms, and the system further includes a blazed grating (38) positioned between the collimating lens (34) and the holographic device (36) to account for variations in the wavelengths of the laser beams due to environmental conditions.
Abstract:
An imaging polarimeter sensor includes an achromatic beam-splitting polarizer that receives a polychromatic image beam of a scene and simultaneously produces a first polarized polychromatic image beam and a second polarized polychromatic image beam. The second polarized polychromatic image beam is of a different polarization than the first polarized polychromatic image beam and is angularly separated from the first polarized polychromatic image beam. The achromatic beam-splitting polarizer preferably includes a Wollaston prism through which the polychromatic image beam passes, and at least one grating through which the polychromatic image beam passes either before or after it passes through the Wollaston prism. An imaging detector receives the first polarized polychromatic image beam and the second polarized polychromatic image beam and produces an output image signal responsive to the first polarized polychromatic image beam and the second polarized polychromatic image beam.
Abstract:
A sensor system senses a scene and includes a dual-band imaging infrared detector lying on a beam path, wherein the infrared detector detects infrared images in a first infrared wavelength band and in a second infrared wavelength band; and a two-color cold-shield filter lying on the beam path between the infrared detector and the scene. The cold-shield filter defines a first aperture size for infrared light of the first infrared wavelength band, and a second aperture size larger than the first aperture size for infrared light of the second infrared wavelength band. The first infrared wavelength band has wavelengths less than wavelengths of the second infrared wavelength band.
Abstract:
An imaging optical system includes a first imaging structure having a first optical axis and a first field of view, wherein the first imaging structure forms an image on a common focal plane, and a second imaging structure having a second optical axis parallel to the first optical axis and a second field of view different from the first field of view, wherein the second imaging structure forms an image on the common focal plane. The imaging structures preferably contain identical lens modules, most preferably identical Petzval lenses, and achromatic or apochromatic prisms of different spatial orientations. A planar sensor structure lies in the common focal plane, wherein the first optical axis and the second optical axis pass through the planar sensor structure.
Abstract:
An imaging sensor system images in two different spectral bands a light beam traveling on a light path from a target. The sensor system includes an imaging sensor operable to image light of the two different spectral bands, a common optics having at least one reflective or refractive optical element, and a wavelength-selective beamsplitter on the light path between the target and the imaging sensor. The wavelength-selective beamsplitter splits the light beam into two subbeams, one subbeam for each of the two different spectral bands, that are respectively incident upon two different locations of the imaging sensor. The imaging sensor may be used to detect buried explosive mines.
Abstract:
An imaging optical system includes a subtelescope array, with at least two subtelescopes, each having a single entrance pupil and an exit light beam. Each subtelescope has an optical pointing axis, and the pointing axes for the subtelescopes are parallel. An imager forms an image from the exit light beams at an image surface, where there is a sensor such as a focal plane array. Preferably, a phase shifter array includes a phase shifter for each of the subtelescopes. The phase shifter array receives the exit light beam of each of the subtelescopes and has a capability to adjust the phase of at least one of the exit light beams. The imager receives the phase-shifted exit light beams.
Abstract:
An interrogator identifies an interrogated object using a light transceiver and a dynamic optical tag associated with the interrogated object. The dynamic optical tag receives an output light beam from the light transceiver and controllably reflects the light beam back to the light transceiver as an input light beam. The dynamic optical tag includes a controllable light reflector that is controllable between a reflective state and a non-reflective state and having a modulation signal input, and a controller that provides the modulation signal input to the controllable light reflector. In operation, the interrogator transmits an interrogation light beam from the light transceiver to the dynamic optical tag, the dynamic optical tag reflects a modulated interrogation light beam back to the light transceiver as the input light beam, and the light transceiver receives and analyzes the input light beam to determine an identity of the dynamic optical tag and the interrogated object. A field-of-regard broadening structure such as a volume hologram preferably overlies the controllable light reflector.