Abstract: A device is provided for receiving a transmission signal and for transmitting an optical beam having an adjustable intensity, wherein the optical beam effects the transmission signal. A transmitter for transmitting the beam has a controller for setting the intensity. A receiver for receiving the transmission signal has an analyzer for outputting a threshold signal if the strength of the transmission signal exceeds a predetermined limit value. A pick-up outputs a start signal for starting the transmission signal. A control unit is connected to the analyzer, the pick-up and the controller. After reception of the start signal from the pick-up, the control unit sets the intensity at the controller to a value which rises continuously from essentially zero until the analyzer outputs the threshold signal, and then leaves the controller unchanged until reception of a new start signal.

Abstract: A method and a device for imaging an object using ultrasound. Transducer elements of a two-dimensional array are interconnected to form sub-arrays. The transducer elements of each sub-array are driven in the transmit mode with the same time delay and read out jointly in the receive mode. In this manner, the number of required time delays is reduced, and parasitic capacitances on the signal lines are diminished.

Abstract: An ultrasonic transducer array in which distances between the array's transducer elements (T.sub.ij) increase in the direction of the rows (x direction) and in the direction of the columns (y direction) from a center of symmetry (S) outward. The integral over a straight-line function f(x) and/or g(y), which steeply decreases on either side of a center of symmetry (S) between the center points (M.sub.ij) of adjacent transducer elements (T.sub.ij), is constant for each row and/or column. Thus, the number of transducer elements (T.sub.ij) is reduced without considerable deterioration of the beam characteristic of the transducer array.