Abstract: For ultrasonic or other mapping systems which use PPI scan, it is desirable to convert the data to a raster scan format for, say, T.V. display. This may be achieved by conversion in a frame store. It is here proposed to time the PPI scan so that points interrogated by the effective receiving beam lie also on line of a cartesian matrix in the mapped region which correspond to the raster lines of the display thus the conversion is directly achieved.

Abstract: A dynamically variable electronic delay line for real time ultrasonic imaging systems is disclosed which controllably phases the signals associated with an array of electromechanical transducer elements and thereby enables selective scanning and dynamic focusing of a target. A controllable variable electronic time delay apparatus is coupled to each of the electromechanical transducer elements of the array having separate write-in and read-out addressing capabilities. The signals associated with a respective ultrasonic transducer element are fed in at selected write-in addresses and subsequently read-out and extracted after an initial time delay interval. The write-in and read-out address pointers of the memory system are continuously sequenced during operation of the device and the time delay interval is a function of the difference between the addresses and the clock rate.

Abstract: The input data format in a single-sector or multi-sector scanner imaging system is chosen such that angulated scan lines intersect a lateral line at equal increments, and along the scan lines the echo signal is sampled at different rates whereby sampling points are along parallel raster lines. Successive scan lines are stored in adjacent columns of a row-column oriented digital memory. Echo data is read out of memory row by row at a variable rate to convert the read-out data back to sector geometry. The image is displayed in real time in a cathode ray tube.

Abstract: A digital electronic system for improving the resolution of dynamic range-handling capacity for received ultrasound in reflection or transmission imaging systems. This system provides a means for preventing loss of structural detail in the display by minimizing the overlapping of signals resulting from the transducer bandwidth and pulse length. It also makes use of a (positive or negative) peak detector to recognize and print as a single point the presence of point targets. With the present technology, a point target may be represented in a B-mode display on several successive scan lines resulting in an abnormally large representation on the display. The actual target is represented by the peak point of the envelope of a series of scan lines in which the point target is displayed. The objective is to print only one point which corresponds with the actual position of the point target with an intensity that corresponds to the intensity of the received signal.

Abstract: An underwater apparatus is described for acoustically inspecting a submerged object at considerable depths such as the lower structural portion of an off-shore drilling rig to determine if the structure has internal defect which cannot be optically detected. The apparatus is intended to operate in depths of up to 500 meters. The apparatus includes an underwater craft for transporting both humans and equipment to the submerged object. The apparatus includes a hand held acoustical and optical probe that is movable by a diver over the surface of the submerged object. The probe includes an array of acoustical transducers that are sequentially activated to acoustically scan the interior of the object. The acoustical transducers are mounted in a flexible support material to accommodate the array to the contour of the surface. The probe additionally includes a real-time display of the acoustical information to assist the diver in effectively inspecting the object.

Abstract: An arrangement is provided for locating and identifying objects using holographic techniques. Improvements are achieved by array configuration and particularly with the use of a plurality of arrays to provide different types of information related to the same object. In one embodiment, a high resolution narrow field-of-view array is provided in combination with a low resolution wide field-of-view array. The low resolution array resolves the ambiguity for object location and the high resolution array permits object identification; wherein the combination of a high resolution narrow field-of-view array and a low resolution wide field-of-view array provides significant advantages over the conventional high resolution wide field-of-view array.A general purpose high resolution wide field-of-view array may be provided for obtaining desired information. In a mode requiring high computational rates, portions of the general purpose array may be selected to provide specific information.

Abstract: This method comprises laying onto the water bottom at least one line of acoustic transducers which are put in energized condition when an iceberg is approaching the location of this line. Acoustic signals are then sequentially transmitted from at least one of said transducers, some of them being reflected by the underwater part of the iceberg and sensed by acoustic receivers located on both sides of the transmitter on the transducer line. The outline of the underwater portion of the iceberg and its draught are determined by automatically drawing the geometrical envelopes of a system of ellipsoids whose foci are the transmitter and the different receivers.

Abstract: 1. In a sonic echo system for classifying objects proud on the ocean floor in which a submarine vehicle moves through the ocean at a constant height above the ocean floor, scanning means for simultaneously deriving separate electric signals corresponding to the sonic reflecting values of parallel strips of the ocean floor extending athwartships of said vehicle, means for simultaneously storing said separate signals on a record medium, and means for serially reproducing the stored signals.

Abstract: A dynamically variable electronic delay line for real time ultrasonic imaging systems is disclosed so as to controllably phase the signals associated with an array of electro-mechanical transducer elements and thereby enable the selective scanning and dynamic focusing of a target. A controllable variable electronic time delay apparatus is coupled to each of the electromechanical transducer elements of the array and in one embodiment thereof constitutes an electronic memory having separate write-in and read-out addressing capabilities. The signals associated with a respective ultrasonic transducer element are fed in at selected write-in addresses and subsequently read-out and extracted after an initial time delay interval. The write-in and read-out address pointers of the memory are continuously sequenced during operation of the device and the time delay interval is a function of the difference between the addresses, as well as the clock rate.