Abstract: A digital conversion circuit with a convergence deviation correcting circuit. A coefficient storing circuit stores coefficients of fundamental correction waves. By weighting these fundamental correction waves using the coefficient storing circuit, a correction data storing circuit is provided with correcting data. Controlling means controls this entire operation. Using the correction data, the convergent deviation of a scanning line of a scanning picture is corrected. By weighting each fundamental correction wave with a weighting coefficient, a synthesized wave is produced. This synthesized correction data is read from a correction data storing circuit in synchronism with deflection scanning and is supplied to a convergence deviation correcting circuit.

Abstract: A data collector for use with a scintillation camera or the like where the camera includes (a) a radiation detector which generates X and Y position signals at least each time a detection event occurs (b) an A/D converter respectively converting the X and Y position signals to digital signals, (c) a converter responsive to the X and Y position signals for respectively converting the position signals to X and Y address signals in accordance with at least a predetermined ratio, (d) X and Y address registers for respectively receiving the X and Y address signals, and (e) a two-dimensional image storage memory responsive to the X and Y address signals for storing data corresponding to the detected event at a memory location within the image storage memory determined by the X and Y address signals. The converter comprises at least one memory matrix responsive to one of the A/D converters for storing conversion data where the memory matrix comprises at least 2.sup.

Abstract: A frequency discriminating circuit for readily discriminating between two signals having closely adjacent frequencies in which the effects of drift of circuit elements are eliminated. A frequency mixer receives the signals to be discriminated which have closely adjacent frequencies f.sub.1 and f.sub.2 and a reference signal with a frequency of f.sub.m. A first low-pass filter coupled to an output of the mixer produces an output signal containing only frequency difference components .vertline.f.sub.1 -f.sub.m .vertline. and .vertline.f.sub.2 -f.sub.m .vertline. between the signal to be discriminated and the reference signal. The output of the first low-pass filter is passed through a second low-pass filter. A phase comparator receives the output signals from the first and second low-pass filters and discriminates the input signals in accordance with a phase difference between the output signals from the first and second low-pass filters.