Abstract:
A system is provided for semi-active laser designation, the system comprising: a guidance and control system having a plurality of wings disposed at an aerodynamically advantageous angle; a plurality of linear sensor arrays configured to measure location of a target, each the sensor array being disposed on a wing of the plurality of wings; and each the linear sensor array providing independent data to the guidance and control system as to the location of the target.
Abstract:
An imaging system includes a first off-axis illumination source for providing a first illumination field at a surface of an illumination modulator such that when the modulator is in a first non-activated mode a zero-order reflected illumination field is directed toward a first illumination blocking device, and when the modulator is in a second activated mode one first order reflected illumination field is directed toward an imaging surface while another first order reflected illumination field is directed toward a second illumination blocking device.
Abstract:
Apparatus for determining the luminous intensity distribution of an automotive head light employs a curved mirror and a curved screen. A solid state camera is used to obtain a pattern of the head light output from the screen. The system requires a relatively small black box into which the head light output is directed. A beam splitter may be employed to relax the constraints on the positioning of the various components within the box. The setting of the test lamp to first and to second preset lateral angular positions at each of which a pattern is captured and the combining of the two patterns permits the use of components which are practical. The use of a linear CCD array permits economies to be obtained by rotating the test lamp or by scanning the linear array over a sequence of angular positions and by constructing a composite pattern from the patterns so generated. In an alternative embodiment, no beam splitter is used. Instead, the arrangement is an off axis arrangement which employs an aspheric lens at the input to the apparatus to reduce spot size at the screen and to improve the angular resolution measurement capability.
Abstract:
An optical LOS toggle uses two refractive optical elements located in the afocal space of an optical sensor. Optical surfaces of the two elements are shaped appropriately to work in combination with lateral displacements of the two elements such that the LOS angle is shifted. For a prescribed, discrete LOS shift, the optical image quality of the toggle module is corrected by a combination of aspheric shapes and diffractive surfaces on the optical surfaces of the two elements. To maintain performance along any radial direction and simplify fabrication, these aspheric or spheric shapes and diffractive surfaces should be rotationally symmetrical. Image quality is further improved through proper selection of the optical materials used to construct the optical elements.
Abstract:
A pupil/image reversal prism (FIG. 2) forms a pupil at an image location. Such a prism has specific applicability in a DCR scheme for a thermal imaging system (FIG. 3a, 31 and 32) in which a passive DCR source is implemented by a pupil imager that forms a pupil onto the image of a thermal scene, thereby providing scene-average radiation to a thermal detector array. The pupil/image reversal prism including an input reflective surface (A), an output reflective surface (B) , a positive reflective surface (C) and an intermediate folding reflective surface (D). The reflective surfaces A and B use total internal reflection to provide both transmissive and reflective operation.
Abstract:
The invention provides a system having a broadband spectrometer with a fiber optic reformattor for field use in detecting and identifying gas clouds within a field of view. The system includes a grating type spectrometer, a fiber optic reformattor, a focal plane detector array and electronics for background signal subtraction techniques for generating spectral signature data which is analyzed for gas detection and outputting a decision making signal for recognition.
Abstract:
An optical LOS toggle uses two refractive optical elements located in the afocal space of an optical sensor. Optical surfaces of the two elements are shaped appropriately to work in combination with lateral displacements of the two elements such that the LOS angle is shifted. For a prescribed, discrete LOS shift, the optical image quality of the toggle module is corrected by a combination of aspheric shapes and diffractive surfaces on the optical surfaces of the two elements. To maintain performance along any radial direction and simplify fabrication, these aspheric or spheric shapes and diffractive surfaces should be rotationally symmetrical. Image quality is further improved through proper selection of the optical materials used to construct the optical elements.
Abstract:
An optical reimager (20) is formed by combining a two-element optical relay (24) with a single-element imager objective (22). The relay (24) comprises a refractive element (26) that is used twice and a mirror (28) that provides a real stop. The reimager can be made diffraction-limited by configuring the mirror with an aspheric surface to correct spherical aberration introduced by both the refractive element (26) and the objective (22), and configuring the objective with an aspheric surface to correct non-spherical aberrations (principally astigmatism and coma). The reimager (20) is described in connection with a thermal imaging application requiring telecentricity and a remote entrance pupil.
Abstract:
A pupil/image reversal prism (FIG. 2) forms a pupil at an image location. Such a prism has specific applicability in a DCR scheme for a thermal imaging system (FIG. 3a, 31 and 32) in which a passive DCR source is implemented by a pupil imager that forms a pupil onto the image of a thermal scene, thereby providing scene-average radiation to a thermal detector array. The pupil/image reversal prism including an input reflective surface (A), an output reflective surface (B), a positive reflective surface (C) and an intermediate folding reflective surface (D). The reflective surfaces A and B use total internal reflection to provide both transmissive and reflective operation.
Abstract:
Apparatus and methods for modifying existing forward looking infrared systems and for forming new forward looking infrared systems. Generally, the system comprises a Galilean afocal system in combination with a reimaging afocal system. A reimaging afocal lens system is formed with at least first and second lenses and a plane for forming an image therebetween. A thermal reference source is positioned in the imaging plane of the reimaging system. The method for modifying an existing forward looking infrared imaging system includes positioning the reimaging system along the optical path of the system between the Galilean lens combination and the scanning device. According to a method for forming a forward looking infrared system an imaging lens system is arranged along an optical path in combination with a detector array to focus collimated radiation upon the detector array. The detector array subtends the field of view along a first direction. A reimaging afocal system is incorporated along the optical path to provide collimated radiation to the imaging lens system and a scanning device is positioned between the reimaging afocal system and the imaging lens system to vary the field of view along a second direction in order to provide a two dimensional image. A Galilean afocal lens system is positioned to receive radiation from a scene and transmit the radiation to the reimaging afocal system.