Abstract: A variable focus system that includes an electrovariable optic (EVO) and a controller operatively configured for changing the focal configuration of the EVO. The EVO includes a plurality of movable optical elements that may be moved substantially in unison with one another so as to change either the focal length of the EVO, the direction of the focal axis of the EVO, or both, depending upon the needs of a particular application. The variable focus system may be used in conjunction with an image source to construct a 3D floating image projector that projects a series of 2D image slices of a 3D image onto corresponding respective image planes in succession rapidly enough that a 3D floating image is perceived by a viewer.

Abstract: A variable focus system (100) that includes an electrovariable optic (EVO) (108) and a controller (112) operatively configured for changing the focal configuration of the EVO. The EVO includes a plurality of movable optical elements (164) that may be moved substantially in unison with one another so as to change either the focal length (f) of the EVO, the direction of the focal axis (132) of the EVO, or both, depending upon the needs of a particular application. The variable focus system may be used in conjunction with an image source (116) to construct a 3D floating image projector (500, 540, 560, 600) that projects a series of 2D image slices (IS1–IS7) of a 3D image onto corresponding respective image planes (IP1–IP7) in succession rapidly enough that a 3D floating image (120) is perceived by a viewer (104).

Abstract: A system and method generate lenticular slides or cards which are optimized for optical imaging by compatible optical systems such as lenticular viewers to generate images which may be reimaged without loss of desirable lenticular image properties. Such systems include optics positioned at a predetermined optical distance from such an optimized lenticular component, to reimage a plurality of images from the lenticular component without loss of desirable lenticular image properties. In one embodiment, a lenticular viewer includes an optical element providing a viewing distance of less than about 18 inches from the lenticular component. The lenticular viewer may also incorporate a virtual baffling method to enhance image contrast by eliminating undesirable background reflections.

Abstract: A flat display panel arrangement including crossed patterns of parallel electrode wires and a reflective layer for increasing panel luminous intensity.

Abstract: Dual radome arrangement (15) comprising inner and outer layers (14,16) respectively transmissive to both modes of radiation operable in a detection system (11), and only one of the modes of radiation, and the outer layer (16) being selectively removable.

Abstract: In a multimode or multispectral electromagnetic detection system (11), a pair of rotatable scanning prisms (13' and 13"), each of said prisms comprising at least a pair of cooperative subprisms (13'a, 13'b, 13"a and 13"b), and the cooperative materials of the subprism being selected so as to ensure that electromagnetic radiation passing through the pair of rotatable prisms is equally deviated in a transverse direction.

Abstract: A multimode, multispectral antenna system (14) for detecting radiation from selected target regions in each of at least a pair of selected spectrum bandwidths through collimating lens (35), and rotatable, cooperative prisms (21) effective for collimating and scanning beams of radiation controllably with respect to said target regions.

Abstract: A radar antenna arrangement with at least a pair of feeds, said arrangement including a corresponding at least a pair of lens elements, the element closest to said feeds effective for collimating the output beam of each of said feed, and the remaining ones of said elements each being associated with a different one of said feeds, whereby at least a pair of separate antenna beams are capble of projection toward a target region.

Abstract: A method of constructing rotatable scanning prisms (13' and 13") for a multimode detection system (13), each including first and second subprisms (respectively 13'a, 13'b and 13"a, 13"b); the method including the steps of chosing an apex angle for one of said subprisms, determining therefrom apex angles at first and second wavelengths for each of said subprisms, and evaluating whether the differences of apex angles at said several wavelengths are acceptably small.

Abstract: A compact reflective head-up display incorporating first and second cooperative and converging mirror elements (34,18) one of which has a rear surface reflector (18), and the other of which (34) is partially transmissive and includes a central reflective portion (33), said first converging mirror (34) combining a remote image viewed by a pilot with a display image provided to said first converging mirror (34) by said second converging mirror (18).

Abstract: A sealing glass composition having a thermal coefficient of expansion (from room temperature to 300.degree. C.) of about 90.times.10 -7/.degree.C. and a softening temperature of about 406.degree. C. is provided and consists essentially of the following ingredients in the following proportions: PbO, 66%; B.sub.2 O.sub.3, 18%; ZnO, 15%; and Fining Agent, 1%.

Abstract: An aiming point locating system has a single LED mounted on the helmet of a pilot in an aircraft and can be used to designate a point on a cockpit display, or the like, without touching the display. An optical device located in front of the LED tapers the energy pattern from the LED so that a sufficiently varying energy field reaches photodiodes located adjacent the display. The photodiodes are oriented toward the pilot so that they respond directly to the tapered energy field thus allowing greater accuracy in electrically identifying the pilot's aiming point on the display. A two stage switch actuated by the pilot has a partially depressed stage causing a visible aiming reticle to appear on display and a fully depressed stage activating the emitter to obtain an electrical output from the photodiodes. Monopulse processing of the signals from the photodiodes is used to create varying X-Y signals which directly correspond to the coordinates of the point on the display viewed by the pilot.

Abstract: An optical system having a spherical mirror is used to collect light from the surface of a turbine blade or the like which is to be contoured. The spherical mirror is located at an equal optical distance from both the test specimen and the linear diode array so that it operates at a one-to-one magnification ratio. The linear diode array is positioned behind the spherical mirror and it receives light focused by the mirror and reflected by a beam splitter through an opening in the center of the mirror. None of the optical elements of the inspection system are located in the plane of movement of the test specimen so that even particularly long items such as a helicopter rotor blade can be contoured. Indentical upper and lower optical systems allows both surfaces of the test specimen to be contoured simultaneously and each system is independently operable and oriented to prevent optical interference.

Abstract: An optical system having a single spherical mirror for collecting light from two directions combined by a beam splitter after the light has been scattered from the surface of a turbine blade or the like. The spherical mirror is located at an equal optical distance from both the surface of the test specimen and a linear detector array so that it operates at a one-to-one magnification ratio. The linear detector array receives light focused by the mirror along a path folded by the beam splitter. This arrangement is helpful in contouring the surface of a turbine blade near a vertical obstruction such as a shroud of a turbine blade since the collection axes of the pickup legs view the incident spot from different directions. None of the optical elements of the inspection system are located in the plane of movement of the test specimen so that even particularly long items such as a helicopter rotor blade can be contoured.