Advanced CCD-based x-ray image sensor system

A method for operating an x-ray system, comprising the steps of:

• providing a solid state x-ray image sensor system within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels, the sensor system being electrically coupled to a controller;
• operating an x-ray source to provide a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed;
• binning together a plurality of the pixels so as to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose;
• calculating, with the controller, a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• applying the second dose of x-rays to the object;
• and
• binning together a plurality of pixels to provide an effectively larger pixel.

A method for operating an x-ray system, comprising the steps of:

• providing a solid state x-ray image sensor system within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels, the sensor system being electrically coupled to a controller;
• operating an x-ray source to provide a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed;
• binning together a plurality of the pixels so as to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose;
• calculating, with the controller, a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• applying the second dose of x-rays to the object;
• and
• detecting an occurrence of a start of the x-ray exposure by the steps of:
• clocking the CCD-based radiation detector to read out a dark signal in a line-by-line format, the step of clocking including a step of generating more clock pulses than there are pixels within a line for overscanning a radiation-responsive CCD read-out register with the additional clock pulses;
• summing charge packets output from the read-out register in response to the additional clock pulses;
• and
• monitoring the summed charge packets to detect an increase in magnitude in the summed charge packets, the increase in magnitude being indicative of an occurrence of a start of an x-ray exposure.

A method for operating an x-ray system, comprising the steps of:

• providing a solid state x-ray image sensor system within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels, the sensor system being electrically coupled to a controller;
• operating an x-ray source to provide a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed;
• binning together a plurality of the pixels so as to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose;
• calculating, with the controller, a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• placing the image sensor system into a low-power state;
• detecting an occurrence of an activity that is a precursor to making an x-ray exposure;
• placing the image sensor system into a higher power operational state;
• flushing dark signal from the pixels of the CCD-based radiation detector while monitoring for a start of an x-ray exposure;
• at the start of the x-ray exposure, terminating the flushing of dark signal and accumulating charge within the pixels;
• and
• at a termination of x-ray exposure, reading out the accumulated charge and forming an image therefrom.

A method for operating an x-ray system, comprising the steps of:

• providing a solid state x-ray image sensor system within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels, the sensor system being electrically coupled to a controller;
• operating an x-ray source to provide a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed;
• binning together a plurality of the pixels so as to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose;
• calculating, with the controller, a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• prior to an occurrence of an X-ray exposure, clocking both first and second readout registers so as to remove dark current from the array;
• at the start of an X-ray exposure, terminating the clocking of both the first and second readout registers;
• and
• after the occurrence of the X-ray exposure, clocking both the first and second readout registers so as to remove X-ray image signal current from the array.

A method for operating an x-ray system, comprising the steps of:

• providing a solid state x-ray image sensor system within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels, the sensor system being electrically coupled to a controller;
• operating an x-ray source to provide a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed;
• binning together a plurality of the pixels so as to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose;
• calculating, with the controller, a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• outputting data from the controller to the solid state x-ray image sensor system, the data specifying at least one operational parameter of the image sensor system including at least one of a duty cycle of at least one clock signal, a level of at least one clock signal, and a bias potential;
• monitoring, from the controller, an output of the image sensor system when operating with the at least one operational parameter;
• and
• varying the at least one operational parameter and executing the steps of outputting data and monitoring until the output of the image sensor system is in agreement with a desired output.

An x-ray system, comprising:

• a solid state x-ray image sensor system disposed within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels;
• and
• a controller electrically coupled to said sensor system, said controller being responsive to an x-ray source providing a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed, for operating said CCD-based radiation detector so as to bin together a plurality of the pixels to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose, said controller further operating to determine a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• wherein the first x-ray dose is approximately 1/(X times Y), where X is a number of pixels binned horizontally and Y is a number of pixels binned vertically within an area of interest.

An x-ray system, comprising:

• a solid state x-ray image sensor system disposed within an enclosure, the sensor system comprising a CCD-based radiation detector comprised of a plurality of radiation responsive pixels;
• and
• a controller electrically coupled to said sensor system, said controller being responsive to an x-ray source providing a first x-ray dose that is significantly less than a normal dose, the first x-ray dose being applied to an object to be x-rayed, for operating said CCD-based radiation detector so as to bin together a plurality of the pixels to develop an output signal that is indicative of an amount of x-ray flux reaching the pixels due to the first x-ray dose, said controller further operating to determine a magnitude of a second dose in accordance with the output signal, the magnitude of the second dose being calculated to obtain an optimum x-ray exposure time for the object;
• wherein said CCD-based radiation detector is comprised of:
• a two dimensional array of charge coupled devices;
• a first readout register disposed along one edge of said array;
• and
• a second readout register disposed along an opposite edge of said array;
• wherein said first and second readout registers are each electrically configurable by said controller for operation as one readout register that transports array output signals in one direction or as two smaller readout registers that transport array output signals in two directions.