An optical filter in the form of a synthetic hologram of an aggregation of point sources recorded on a photographic plate using a standard two-beam holographic system. The required filter function of the optical filter is established and generalized into a periodic function which is then synthesized by a finite number of harmonics in a spatial frequency domain. Where the filter function has a degree of symmetry, the synthesis process is comparatively simple with only the first several harmonics ...

An electrostatically deflectable plate spatial light modulator with light reflecting plates (106) composed of aluminum alloy and with symmetrically located supporting hinges (108) connecting the plates (106) to support posts (104); this provides a thick stiff plate and a thin compliant hinges with deflection perpendicular to the plane of the plates.

A deflectable beam spatial light modulator formed from a structure of a reflecting layer, typically metal, on a spacer layer, typically photoresist, which in turn is on a substrate containing electronic addressing circuitry is disclosed. Also, the method of fabrication including a plasma etch after dicing of the substrate into chips is disclosed.

A fixed wing airplane having a substantially transparent fuselage, which in straight and level flight permits both the pilot and copilot to see the entire ground and sky in all directions and from nadir to zenith, with the exception of roughly two steradians of solid angle in the quadrant above and behind him. The necessary opaque struts which cross the transparent areas are so oriented and dimensioned that the distant scene as seen through the major areas of the plane appears to be continuous, ...

A digital spatial filter system includes means for separating an image formed of a matrix of pixels into four regularly distributed interleaved subimages from alternate rows and columns of the matrix pixels; means for convolving each of the four subimages with two orthogonal unidimensioanal, vectors of a convolving kernel to produce four filtered subimages; and means for recombining said convolved four filtered subimages into the original image filtered.

A technique for reducing the total storage used in representing data having spatial extents. The data is represented in a tree structure having a plurality of nodes, wherein each of the nodes has parent and child relationship to one or more others of the nodes in the tree structure. An encoded representation of the relation of a child node's extents with respect to its parent is stored in the node. A preorder traversal of the tree structure is performed to store it compactly in an output file.

A signal image is transmitted by write light from a transmission type liquid crystal element 4 to an optically-addressed type parallel-aligned nematic-liquid-crystal spatial light modulator 6. The numerical aperture NA.sub.L of a relay lens 5, the pitch P of the pixel structure of the transmission type liquid crystal element 4, and the wavelength .lambda. of light from the write light source 1 are set with the condition 1/2P<NA.sub.L /.lambda.<1/P. As a result, the signal component caused ...

A modulator of the type including an array of light modulating elements. To afford fast response and thus greater modulation bandwidth these elements, each comprising a pair of electrodes and a reflector, are defined in a sheet layer of electro-optic solids material. In particular, this material may be of PLZT ceramics material or of a similar ceramic having a high electro-optic coefficient (quadratic). To advantage, the electrodes may be embedded in the sheet layer. Each modulating element is a...

An electro-optical device for providing spatial modulation of an incoming electromagnetic wave signal, and preferably a two-dimensional incoming signal applied orthogonally to an input plane of the device, which device includes an array of modulation regions for providing such modulation of portions of the incoming signal. An array of first reflective mirrors are positioned so as to direct the incoming electromagnetic wave signal portions through the interaction layer regions of the modulation r...

Spatial separation of first and second spectral components in magnetic resonance imaging systems is accomplished by causing the first and second spectral components to generate first and second signals of different frequencies which are spatially separated and converting the spatially separated signals to image data for first and second images of said first and second spectral components respectively.