Abstract: The invention relates to a process for the formation of an image obtained from an array of detector pixels comprising at least one detector pixel, the image formed constituted by at least one set of P image pixels for each detector pixel, characterized in that it successively comprises: a stage (E2) making it possible to create N elementary pixels from one detector pixel, N being an integer equal to or lower than P and a stage (E3) of the random distribution of events received by a detector pixel in the N elementary pixels corresponding thereto. The invention applies to the field of medical imaging.

Abstract: A compact detection device for a gamma camera comprises: several detectors (4a, 4b, . . . ) adjacent to each other to form a detection plane (4); a first ceramic substrate (1); a second substrate (3) on which the detectors are arranged; means (10b) of polarizing the detection plane and the signal processing means (10c) for the signal detected by the said detection plane, located in the first substrate; and a ground plane (2) placed between the first and the second substrates.

Abstract: A device for collection, digital encoding, and processing of signals from plural photo-detectors in a camera. The device includes plural digital encoding units, each digital encoding unit in the plural encoding units being associated with one individual photo-detector in the plural photo-detectors, and including a summation device and an analog-digital converter. A digital processing unit is connected to each encoding unit. Such a device may find particular application to gamma-cameras.

Abstract: A semiconductor detector including at least one block of detector pixels, each detector pixel being composed of a semiconductor element with a first face covered by a first armature and a second face covered by a second armature. The detector pixels are assembled side by side such that the first armatures define a detector plane. The first armatures are covered by a plane conducting structure that connects them together electrically. The detector does not have any dead area in which detection is impossible. The semiconductor is particularly applicable to detection of ionizing radiation (gamma rays, X-rays, etc.

Abstract: A micro gamma camera having several gamma radiation detection devices adjacent to each other. The detection devices are laid out above an information processing device that processes information output by the detection devices. Each of the detection devices includes: a plurality of detectors positioned adjacent to each other to form a detection plane; a first substrate including a detection plane polarizer and a first signal processor for processing the signal detected by the detection plane; a second substrate placed between the detection plane and the first substrate; a ground plane placed between the first and second substrates; and a third substrate including second and third signal processors.

Abstract: A detection head and collimator for a gamma camera. The detection head includes several elementary detectors with semiconductors adjacent to each other to form a detection plane. The collimator is placed in front of the detection plane and includes a number of ducts laid out in a repetition pattern. The shape of the elementary detectors and the repetition pattern are rectangular in the detection plane.

Abstract: A system for processing signals from a radiation detector with semiconductors. A plurality of elementary detectors are placed side-by-side along a detection surface or a detection volume in which radiation referred to as incident radiation is capable of giving up its energy in at least one interaction. The device includes the supplying in response to each incident ray, an amount of energy corresponding to the sum of the energies given up during each interaction induced by the incident radiation. This device may be used in medical imaging.

Abstract: Process for real time sorting of signals from several semi-conductor detection elements in which: a) during a calibration phase: amplitude data and signal rise time data are established for each event signal, a biparametric detection spectrum with amplitude and rise time data is acquired, a biparametric acceptance window corresponding respectively to an amplitude-rise time correlation is established, and b) during an examination phase: an amplitude, rise time data pair is established in real time for each event signal detected, the events are sorted in real time, selecting the signals according to whether their amplitude and rise time data are or are not within the window.

Abstract: Method and apparatus for determining a position of an event. The system processes signals from an assembly of N photodetectors and includes a signal generator for producing a signal representing the value of the maximum, or the energy, of a pulse delivered by the photodetector and is digitized. It also includes a signal generator for producing a threshold-exceeded signal for each photodetector when the amplitude of the signal representing the value of the maximum, or the energy, of the digitized pulse is greater than the threshold. It also includes a signal generator common to the photodetectors, for delivering a signal representing a position of an event as a function of the threshold-exceed signals. This device can be used with gamma cameras.

Abstract: A nuclear detection process and an apparatus therefore, including base potential correction and corresponding apparatus in which the base potential is measured by establishing a histogram of the values of the detected pulses and the value of the abscissa of the first peak of the histogram is determined and is subtracted from the values of the detected pulses.

Abstract: A nuclear detection device, especially a gamma-camera type device which features deconvolution filters. In a gamma-camera variant, the device includes digital filters for deconvoluting electric measuring signals. A transfer function of these filters is opposite that of a circuit having formed the electric signals. It is then possible to separate any pulses which would overlap. Such a system finds particular application in nuclear physics and in particular in the medical field.

Abstract: To take account of the decrease time constant of the intensity of the light scintillation and the statistical fluctuation of the scintillation, which is a resolution deterioration factor, it is appropriate to integrate the electric pulse resulting from the detection of an event by photomultiplier tubes. If, during this integration, a stacking phenomenon occurs, a second pulse is superimposed on the first and falsifies the calculation of the scintillation coordinates. This stacking is eliminated by validating the calculation of these coordinates by checking the value reached by the scintillation energy at the end of said integration. The value of this energy is measured by integrating the signal representing the intensity of the light scintillation.

Abstract: The invention relates to a method for processing locating pulses supplied by a gamma camera and to a gamma camera utilizing this method. In accordance with the invention, locating pulses (X.sup.+,X.sup.-,Y.sup.+,Y.sup.-) are taken into account by a calculator circuit (12) which performs the standardization of an (X,Y) coordinate signal proportional to the difference of two locating pulses (X.sup.+ -X.sup.-) along an axis by the sum of these same two locating pulses (X.sup.+ +X.sup.-) along this axis.

Abstract: In a gamma camera utilizing a collimator, a scintillator, a network of photomultiplier tubes and an array of matrices of resistors, the balanced pulses supplied by this array are measured by integration in an integrator stage which supplies locating pulses. These locating pulses serve the purpose of generating coordinate signals applied to a visual display device. Prior to integration, the direct interference components affecting the balanced pulses are eliminated by capacitive coupling of the array of matrices to the integrator stage. In order to prevent this coupling introducing means direct components at high counting rates, the output of this coupling means is periodically forced to assume the value of a base potential.