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

A real-time imaging device for storing and retrieving an imaging signal resulting from incident ionizing radiation bursts, comprising:

• a scintillation layer;
• an array of photosensitive pixel sensors optically coupled to the scintillation layer, each photosensitive sensor having a first semiconductor layer doped to a first conductivity type, a second semiconductor layer doped to a second conductivity type, and an intrinsic second semiconductor layers;
• and
• a plurality of transistors, each having a predetermined resistance, connected to respective of said photosensitive sensors for reading out the stored signal, each photosensitive sensor and the respective transistor connected thereto forming one pixel, wherein the capacitance of each of the photosensitive sensors when multiplied by the resistance of said respective transistor yield a time constant .tau..sub.RC, in .mu.sec which satisfies the following relationship and which thereby permits real-time imaging of said incident radiation bursts, ##EQU5## where P=the pixel-pixel pitch in .mu.m, where .about.25.ltoreq.p.ltoreq..about.10,000,
• L=the length, in cm, of one column of pixels sensors of the array, where .about.2.ltoreq.L.ltoreq..about.60,
• IFPS=instantaneous frame ratio per second which is the effective rate at which the array is being readout, where .about.1.ltoreq.IFPS.ltoreq..about.500, and
• SN=the inverse of the degree of which each pixel sensor needs to be sampled and thus recharged, where .about.10.ltoreq.SN.ltoreq..about.10,000.

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, .tau..sub.RC, in .mu.sec 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 .mu.m, where .about.25.ltoreq.P.ltoreq..about.10,000,
• L=the length, in cm, of one column of pixels sensors of the array, where .about.2.ltoreq.L.ltoreq..about.60,
• IFPS=instantaneous frame rate per second which is the effective rate at which the array is being readout, where .about.1.ltoreq.IFPS.ltoreq..about.500, and
• SN=the inverse of the degree to which each pixel sensor needs to be sampled and thus recharged, where .about.10.ltoreq.SN.ltoreq..about.10,000.

A real-time imaging device having a plurality of arrays one stacked upon the other, with each array of said plurality of arrays having a plurality of sensors arranged in rows and columns, each sensor of each array comprising:

• a scintillation layer to convert incident radiation signals into a visible light signal;
• a photosensitive element comprising 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;
• a thin film field effect transistor, connected to said photosensitive element and formed upon a common substrate with said photosensitive element, for reading out a signal from said element, said transistor and respective photosensitive element forming one pixel, wherein a capacitance of each photosensitive element when multiplied by a resistance of the transistor connected thereto yield a time constant, .tau..sub.RC, in .mu.sec which satisfies the following relationship and which thereby permits real-time imaging of said incident relation signals, ##EQU7## where P=the pixel-pixel pitch in .mu.m, where .about.25.ltoreq.P.ltoreq..about.10,000,
• L=the length, in cm, of one column of pixels sensors of the array, where .about.2.ltoreq.L.ltoreq..about.60,
• IFPS=instantaneous frame rate per second which is the effective rate at which the array is being readout, where .about.1.ltoreq.IFPS.ltoreq..about.500, and
• SN=the inverse of the degree to which each pixel sensor needs to be sampled and thus recharged, where .about.10.ltoreq.SN.ltoreq..about.10,000.