Abstract: The present invention, in one form, is an imaging system which, in one embodiment, alters the configuration of a detector array and a data acquisition system to determine degraded component performance and generate fault isolation information. More specifically, by altering the configuration to include different combinations of detector array cells, interconnections, and one or more data acquisition channels, fault isolation information is generated.

Abstract: A cable for a computed tomography system is described. In one embodiment, the cable electrically connects a detector module to a data acquisition system. The cable includes a conductor layer, an insulating layer and a shield layer having a thermal barrier. The thermal barrier reduces the amount of heat which is transferred from the data acquisition system to the detector module.

Abstract: An elastomeric connector apparatus for a computed tomography system is described. In one embodiment, the elastomeric connector apparatus electrically connects a detector module flexible cable to a data acquisition backplane. Flexible cable and backplane connector pads are electrically connected with an elastomeric connector. The elastomeric connector apparatus allows the low level analog outputs from the detector module photodiodes to be transmitted to the backplane without a large pin connector array.

Abstract: A scalable data acquisition system (SDAS) that may be used in connection with both single slice and multislice imaging systems is described. Generally, the SDAS in configured for use in a computed tomography system and converts the low level electrical current signal from the x-ray detector to digital values for image reconstruction, display and archive. The SDAS also includes an anti-alias filter for each cell prior to analog to digital conversion (ADC). More specifically, the analog current signals from the detector are supplied to the SDAS input channels via shielded ribbon or flex cables. The cables are connected to the SDAS at the SDAS backplane. The SDAS Converter boards are also plugged into the SDAS backplane. This interconnection provides several advantages. For example, the backplane enables ganging the detector cells on the outside edges of the fan beam. The backplane also allows a redistribution of the detector cells to appropriate converter boards.

Abstract: A data acquisition filter for a dual beam CT machine uses two spectral filters for alternately receiving the signal from each detector depending on the state of the x-ray beam. When one filter is filtering the detector signal, the other filter is in a "hold" state where its output and internal values are frozen. Each filter effectively filters only the signal occurring during one beam state without being effected by the signal occurring during the other beam state or by the passage of time during the other beam state The output of the filter in the holding state is constant and may be sampled at any time during this period.

Abstract: An autozeroing apparatus is disclosed for correcting the offset error in a computerized axial tomography (CAT) scanner data acquisition subsystem (DAS). The DAS includes a floating point amplifier for applying discrete amplification factors, or gain range segments, to an analog input before conversion to digital in an A/D converter. A digital autozero circuit is connected to the output of the A/D converter and adds a digital offset value to each A/D converter sample during data acquisition to correct for the net offset errors throughout the DAS. Separate storage latches are included for storing offset values corresponding to each gain range segment, and the offset value used for each sample correction corresponds to the gain range segment used for that sample. During an autozero reference interval, a reference voltage is applied to the DAS and the offset values are updated so as to force the corrected A/D converter output to agree with the reference voltage.

Abstract: A processor for use in CAT X-ray systems and NMR systems performs floating point arithmetic operations in parallel to shorten processing time. A single program memory and program sequencing unit operates a set of floating point arithmetic units to carry out parallel operations on data set storeed in respective data memories. An integer processor unit executes logical operations and a shared data memory stores constants and other data which is required by the integer processor unit and which is common to the operations performed by all of the floating point arithmetic units.

Abstract: A high precision composite amplifier for use in a data acquisition subsystem of a Computerized Tomography (CT) scanner provides enhanced high speed response in terms of reduced settling time. The speed improvement is due to a novel compensation network in which a high frequency pole and a zero in the open loop response characteristic for the composite amplifier are forced to cancel despite component and temperature variations. The resulting amplifier exhibits a simple, higher speed, single pole response. An adjustable circuit is provided for adjusting the placement of the zero to assure optimum pole/zero cancellation.

Abstract: Improved data converter circuitry for a CT data acquisition system is disclosed which makes use of a programmable gain amplifier whose gain is set according to the magnitude of a detector input signal by selecting one of several resistor voltage-divider paths at the input of a fixed gain amplifier. An auto-zero loop uses an intergrating op-amp to provide periodic correction to offset voltage of the fixed gain amplifier. In a modified embodiment, an auto-zero loop is provided for correction of both the fixed gain amplifier and a serially-connected A/D converter.

Abstract: A control console has a small and compact array of twenty-seven illuminable push buttons arranged in three continuous groups of nine each. The buttons in the upper group relate to anatomical areas in upper parts of the body, and the buttons in the lower group relate to areas in the lower parts of the body and the extremities. The middle group are control and x-ray technic variation buttons. Different anatomical regions are indicated by pictographs on the push buttons in an organized array in the upper and lower groups. Pressing at least one push button in the middle group and one in the other groups sets up and displays the x-ray exposure parameters corresponding with the equivalent of the user's priority technic, including safe patient exposure and safe x-ray tube operating time, which has been stored in a memory, for the particular anatomical region. The programmed values for tube kV, mA, mAs and time are displayed.