A digitizer having a pointer or cursor driven by an alternating carrier signal and a grid of sequentially enabled parallel spaced conductors inductively coupled to the cursor in which enabling of the conductors is initiated at an origin conductor and continues with a serial scan of the conductors until a phase change is detected when the cursor is between the origin conductor and an enabled conductor. The grid is sub-divided into overlapping sections which are scanned in sequence until the point...

A bidirectional frequency scan system in which a variable scan control voltage across a variable tuning reactance in the tuning circuitry is determined by the charge on a scan capacitor. Means are provided for selectively increasing or decreasing the charge on the scan capacitor so that when the capacitor is charging the system scans in one direction, and when the capacitor is discharging the system scans in the opposite direction.

Diffractive elements which are reported by acoustical waves in seismic exploration can be defined by a process wherein seismic traces from a plurality of seismic receivers are shifted by T (T = the travel time from a particular acoustical wave source to a diffractive element and thence to a particular seismic receiver), whereupon the seismic traces are added and the summation of the added seismic traces is indicative of the diffractive power of each diffractive element. The invention further com...

A photoerasable scan converter is described for converting digital and/or optical input to a raster signal output for storage in a buffer and subsequent monitoring. In combined image mode, a charge pattern representing a first image is painted on the photoconductive target of a Vidicon tube by an electron beam in directed-beam mode. A modification or modulation of a charge pattern representing a second image is provided on the target by exposing said screen to the second image through an optical...

A first predetermined scan configuration, such as a circular scan for instance, of wave energy is converted into a different second predetermined scan configuration, such as a straight line for instance, of wave energy by means of a plurality of separate holograms.

A digital scan converter is disclosed in an exemplary radar environment where range bin data samples are received in range bin series from successive range sweeps for a moving target indication. A single memory having a read-write cycle capable of reading old data and immediately writing new data for each location addressed, is employed with an address generator that alternates between two modes of operation. The first mode generates a continuous numerical sequence of addresses which scans the m...

An automatic control system for changing aspect ratio in the reproduction of motion pictures, wherein the recorded images are in accordance with an anamorphic or other wide screen process, and the desired reproduction thereof is of standard size or of a different aspect ratio. A typical example is the conversion of images from movie film of one aspect ratio to images on film, video tape or the like of aspect ratio suitable for television usage. Portions of the original images are selected, and a...

A system for accurately reciprocally driving a structural element, such as a flat reflector. The system includes a torque motor for driving the reflector, a position pick-off device for monitoring the position of the reflector, and an electronic unit comprising feedback paths coupling the pick-off device to the torque motor. The electronic unit includes a negative feedback positioning loop enclosed within an outer positive feedback hysteresis loop. The positioning loop comprises a type II (doubl...

A raster scan character generator which forms different sized characters with dot pattern forming nets which are shared by characters employing common dot patterns. The generator includes a timing control which responds to a size code to selectively change the dot signal frequency as well as to perform a size conversion operation on the odd and even scan line signals. A character stroke or dot pattern encoder responds to a selected character to provide dot pattern or stroke identifier signals to...

An improved method and apparatus are shown for selecting and registering data bits from a single scan line which data bits represent only a portion of an alpha-numeric character. Registration is controlled by the location of the data bits representing the portion of the character from each scan and a registration reference signal determined from the location of data bits from previous scans.