Abstract: The present invention relates to radiographic imaging apparatus for taking X-ray images of an object. In various two-panel radiographic imaging apparatus configurations, a front panel and back panel have substrates, arrays of signal sensing elements and readout devices, and passivation layers. The front and back panels have scintillating phosphor layers responsive to X-rays passing through an object produce light which illuminates the signal sensing elements to provide signals representing X-ray images. The X-ray apparatus has means for combining the signals of the X-ray images to produce a composite X-ray image. Furthermore, the composition and thickness of the scintillating phosphor layers are selected, relative to each other, to improve the diagnostic efficacy of the composite X-ray image. Alternatively, a radiographic imaging apparatus has a single panel having arrays of signal sensing elements and readout devices and scintillating phosphor layers that are disposed on both sides of a single substrate.

Abstract: Apparatus for acquiring an elongated radiographic image. The apparatus includes a flat panel electronic detector of radiographic images, the detector having a known length; and a transport mechanism for mounting the detector for movement in a direction parallel to the known length so that the detector can be positioned in sequential contiguous partially-overlapping positions to acquire a radiation image greater in length than the detector length. At least one marker is disposed in a region corresponding with each partially-overlapping position of the detector.

Abstract: A wireless, independent digital imaging sensor utilizes an external charge balance capacitor to establish a sense voltage at a common node between the charge capacitor and the pixel intrinsic capacitors in the sensor panel. A variable width pulse train responds to the sense voltage to control injection of charge to the external capacitor to maintain a constant voltage at the common equal to a reference voltage. An increase in pulse width above a threshold level representative of the onset of X-ray exposure is detected to generate an output control signal used to control subsequent image acquisition functions of the imaging sensor.

Abstract: A wireless X-ray detector for a digital radiography system with remote detection of impinging radiation from the system X-ray source onto a sensor panel having amorphous or crystalline silicon photodiodes or metal insulated semiconductor (MIS) sensors. Changes in current in the photodiode bias supply circuit is sensed to generate a signal indicating presence of radiation. Improved detection of X-ray cessation is achieved either by leaving at least one line of sensors connected between the bias supply circuit to a virtual ground during charge accumulation or by using an X-ray presence detector circuit that increases the sensitivity of the detector circuit to bias circuit current changes occurring after onset of the radiation.

Abstract: Apparatus for acquiring an elongated radiographic image. The apparatus includes a flat panel electronic detector of radiographic images, the detector having a known length; and a transport mechanism for mounting the detector for movement in a direction parallel to the known length so that the detector can be positioned in sequential contiguous partially-overlapping positions to acquire a radiation image greater in length than the detector length. At least one marker is disposed in a region corresponding with each partially-overlapping position of the detector.

Abstract: Apparatus for acquiring an elongated radiographic image comprising: a flat panel electronic detector of radiographic images, said detector having a known length; and a transport mechanism for mounting said detector for movement in a direction parallel to said known length so that said detector can be positioned in sequential contiguous positions to acquire a radiation image greater in length than said detector length.

Abstract: An x-ray imaging detector having an x-ray converter layer, a pixellated detection array closely adjoining the x-ray converter layer, and a substrate supporting the detection array, the substrate having a surface nearest said x-ray converter layer, the substrate including one or more elements having atomic numbers greater than 22, said elements having a total concentration in the substrate of greater than about 1 mole percent relative to the total number of moles of elements having atomic numbers of 22 or less, the substrate having a thickness in the same direction as the thickness of the x-ray converter of less than about 0.2 mm.sup.2 divided by the thickness of the converter in millimeters, the substrate having a dimensionless absorption exponent of greater than about 0.5 and less than about 5 for gamma ray emission of Am.sup.241 at about 60 keV;whereinAE(Am.sup.241 60 keV)=t*(k.sub.1 e.sub.1 +k.sub.2 e.sub.2 +k.sub.3 e.sub.3 + . . . )wherein AE(Am.sup.

Abstract: An ionizing radiation imaging detector, for use with a ionizing radiation beam source comprising a pixellated conversion-detection unit, and a substrate supporting the conversion-detection unit. The substrate includes one or more elements having atomic numbers greater than 22, the elements having a total concentration in the substrate of greater than about 1 mole percent relative to the total number of moles of elements having atomic numbers of 22 or less. The substrate has a dimensionless absorption exponent of less than 0.5 for gamma ray emission of Am.sup.241 at about 60 keV;whereAE(Am.sup.241 60 keV)=t*(k.sub.1 e.sub.1 +k.sub.2 e.sub.2 +k.sub.3 e.sub.3 + . . . )and wherein AE(Am.sup.241 60 keV) represents the absorption exponent of said substrate relative to the about 60 keV gamma ray emission of Am.sup.241 ; t represents said thickness of said substrate in the principle direction of propagation of said x-ray beam; e.sub.1, e.sub.2, e.sub.3, . . .