Thin-film, flat panel, pixelated detector array for real-time digital imaging and dosimetry of ionizing radiation

Claim 1

A real-time imaging device for use with an incident ionizing radiation beam, comprising: signal conversion means including an array of pixel sensors, each having a predetermined capacitance, for converting the incident ionizing radiation beam into an electron hole-pair signal and storing said signal at the plurality of pixel sensors; and switching means including a plurality of transistors, each having a predetermined resistance, wherein each of said plurality of transistors reads out the signal stored by an associated one of said plurality of pixel sensors, wherein the capacitance of one of the plurality of pixel sensors when multiplied by the resistance of an associated transistor yield a time constant, τ RC , in μsec which satisfies the following relationship, which thereby permits real-time imaging of said radiation beam, ##EQU4## where P=the pixel-pixel pitch in μm, where ˜25≦P≦˜10,000, L=the length, in cm, of one column of pixels sensors of the array, where ˜2≦L≦˜60, IFPS=instantaneous frame rate per second which is the effective rate at which the array is being readout, where ˜1≦IFPS≦˜500, and SN=the inverse of the degree to which each pixel sensor needs to be sampled and thus recharged, where ˜10≦SN≦˜10,000.

Claim 29

A device for storing and retrieving an imaging signal obtained as result of diagnostic X-rays for purposes of realizing real-time images, comprising: an array of a plurality of photosensitive pixel sensors arranged in rows and columns; each of said sensors having a first semiconductor layer doped to a first conductivity type, a second semiconductor layer doped to a second conductivity type, and an intrinsic layer sandwiched between said first and second semiconductor layers; an upper electrode layer transparent to visible light connected atop said first semiconductor layer of each of said sensors; a lower electrode layer connected below said second semiconductor layer of each of said sensors; and a plurality of thin film field effect transistors each having a predetermined resistance, each of which is connected to a respective of said plurality of sensors for reading out an imaging signal stored in said respective sensor upon irradiation by said diagnostic X-rays, each combination of sensor connected to a respective transistor corresponding to one pixel, wherein the capacitance of each sensor when multiplied by the resistance of the respective transistor to which said sensor is connected yield a time constant, τ RC , in μsec which satisfies the following relationship and which thereby permits real-time imaging of said diagnostic X-rays, ##EQU6## where P=the pixel-pixel pitch in μm, where ˜25≦P≦˜10,000, L=the length, in cm, of one column of pixels sensors of the array, where ˜2≦L≦˜60, IFPS=instantaneous frame rate per second which is the effective rate at which the array is being readout, where ˜1≦IFPS≦˜500, and SN=the inverse of the degree to which each pixel sensor needs to be sampled and thus recharged, where ˜10≦SN≦˜10,000.

Claim 30

A device for storing and retrieving an imaging signal obtained as result of diagnostic X-rays for purposes of realizing real-time images, comprising: an array of a plurality of photosensitive pixel sensors arranged in rows and columns; each of said sensors having a first semiconductor layer doped to a first conductivity type, a second semiconductor layer doped to a second conductivity type, and an intrinsic layer sandwiched between said first and second semiconductor layers; an upper electrode layer transparent to visible light connected atop said first semiconductor layer of each of said sensors; a lower electrode layer connected below said second semiconductor layer of each of said sensors; and a plurality of thin film field effect transistors each having a predetermined resistance, each of which is connected to a respective of said plurality of sensors for reading out an imaging signal stored in said respective sensor upon irradiation by said diagnostic X-rays, each combination of sensor connected to a respective transistor corresponding to one pixel, wherein the capacitance of each sensor when multiplied by the resistance of the respective transistor to which said sensor is connected yield a time constant, τ RC , in μsec which satisfies the following relationship and which thereby permits real-time imaging of said diagnostic X-rays, ##EQU6## where P=the pixel-pixel pitch in μm, where ˜25≦P≦˜10,000, L=the length, in cm, of one column of pixels sensors of the array, where ˜2≦L≦˜60, IFPS=instantaneous frame rate per second which is the effective rate at which the array is being readout, where ˜1≦IFPS≦˜500, and SN=the inverse of the degree to which each pixel sensor needs to be sampled and thus recharged, where ˜10≦SN≦˜10,000.