A spatial filter has a plurality of uniformly weighting spatial filters for defining as pixel data of a given pixel a value corresponding to a sum of pixel data in a predetermined square area near the given pixel. The characteristics of these uniformly weighting spatial filters are linearly coupled to obtain substantially circular filter characteristics.

A method and apparatus for processing audio signals utilizing reverberation in combination with directional cues to capture both the temporal and spatial dimensions of a three-dimensional natural reverberant environment. Reverberant streams are generated and directionalized to simulate a selected model environment utilizing pinna cues and other directional cues to simulate reflected sound from various spatial regions of the model environment.

Spatial positioning method and device are disclosed using at least one stationary station means positioned stationary in a field to be measured and providing referent site(s) in an area to be set-out or staked-out, and a portable position sensor means having at least two sensor elements, the position of each sensor element being indicated by a co-operation between the sensor element and said at least one stationary station means. In order to make said spatial positioning system able to measure t...

An interferometer comprises a non-uniform beam splitter (34) which splits an incoming beam (30) of energy into two beams (36, 38). The two beams (36, 38) are taken from parts of the incoming beam (30) which overlap. The two beams (36, 38) are fed spacially separated energy feeds (44, 46) and then fed to a comparator to produce sum and difference channels (54, 58). The sum and difference channels (54, 58) are guided to a means for detecting a difference in phase (60) between the sum and differenc...

An optical communications system for coding, transmitting, receiving, and coding digital message signals is described. A beam from a coherent optical source, such as a laser, is transmitted through an aperture in which there is disposed a random phase screen, e.g., ground glass. One or more isometric bar gratings containing the coded message data in a particular amplitude distribution pattern are disposed adjacent to the ground glass in the optical transmission path. The ground glass, phase scre...

A handheld device includes a motion detection module operable to detect motion of the device within three dimensions and a memory maintaining a spatial signature comprising a particular movement of the device with respect to a reference position. The device also includes a signature detection module operable to determine an input signature by identifying an initial position of the device and tracking movement of the device in reference to the initial position using the motion detection module, t...

A spatial intrauterine contraceptive insert which after being introduced by means of a normal inserter into the uterus cavity takes on by itself the appearance of a spatial body. The insert has two arms 1, 2, the ends of which are connected permanently and formed into two spatial spirals along axes 4, 5 that intersect in an acute angle. In cross-section, the arms 1, 2 take on the shape of a circle. The parts of the arms 1, 2 which are formed as spirals of about 11/2 turns have the appearance of ...

A light spatial modulator typically used with computer holography for modulating incident laser light with respect to two factors of three characteristic factors of a light wave, that is, the amplitude, the phase and the direction of polarization, said modulator consisting of two component modulator means tandemly disposed with respect to the incident light, each for one factor of the light wave to be modulated and each component modulator means including a plate of ferroelectric crystal such as...

A hologram in the form of a hologram disk is constructed from an optical encoder disk containing binary information. The hologram disk may be mounted on a shaft for rotation therewith as in conventional encoders. The hologram disk is illuminated by a reconstruction beam such as a laser beam to form an image of the original optical encoder disk. An array of photodetectors positioned adjacent the reconstructed image reads out the binary information contained in the encoder disk.

In a squint-mode radar data processor, spatial filtering provides spatial frequency resolution in azimuth corresponding to a uniform transverse lineal resolution. For a radar data matrix of range trace versus pulse repetition interval, the read-scan rate at which each range bin is scanned is increased as a direct function of range, whereby the fixed bandpass of an output filter represents a spatial frequency resolution which varies with range and corresponds to a fixed lineal resolution at all r...