Back to results
US 6,201,257 B1Granted
Semiconductor X-ray photocathodes devices
AssigneeAdvanced Scientific Concepts, Inc.
InventorsRoger Stettner, Howard W. Bailey
Life of this patent
Estimating the term…
Abstract
An energy dispersive x-ray and gamma-ray photon counter is described. The counter uses a photon sensor which incorporates a unique photocathode called Advanced Semiconductor Emitter Technology for X-rays (ASET-X) as its critical element for converting the detected photons to electrons which are emitted into a vacuum. The electrons are multiplied by accelerations and collisions creating a signal larger than the sensor noise and thus allowing the photon to be energy resolved very accurately, to within ionization statistics. Because the signal is already above the sensor noise it does not have to be noise filtered therefore allowing high-speed counting. The photon sensor can also be used as a device to visualize and image gamma-ray and x-ray sources.
Claims39
An energy resolving and counting device for resolving a flux of x-ray or gamma-ray photons, which has an energy spectrum, into one or a plurality of energy bins, for counting the number of photons in each energy bin and for storing and displaying the results comprising
- one or a plurality of sensors for absorbing the photons producing separate electrical signals for each photon representative of the energy of each photon,
- drive electronics to control the integration time of the sensor and control the transfer of signals to output electronics and to data storage and display circuitry
- said output electronics separating the photon signals into the energy bins, digitizing the photon signals and counting the photons in each energy bin,
- data storage and display circuitry storing count information and displaying the count information,
- said sensor(s) comprising
- a photocathode device for absorbing the photon and emitting one or a plurality of electrons,
- amplification means to multiply the number of electrons and
- readout means to convert the electrons into an electrical signal
- said photocathode device comprising
- detector structure means for absorbing the photons and creating one or a plurality of electron-hole pairs,
- voltage means for creating electric fields within and outside the device to separate the electrons from holes and aid in electron emission,
- electrical contacts and shields to create, shape and amplify the electric fields from the voltage means,
- emitter structure means comprising cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device.
10 more elements
An x-ray, gamma-ray, visible or infrared photon sensor comprising
- a photocathode device for absorbing the photon and emitting one or a plurality of electrons,
- amplification means to multiply the number of electrons and
- readout means to convert the electrons into an electrical signal,
- said photocathode device comprising
- detector structure means for absorbing the photons and creating one or a plurality of electron-hole pairs,
- voltage means for creating electric fields within and outside the device to separate the electron from the hole and aid in electron emission,
- electrical contacts and shields to create, shape and amplify the electric fields from the voltage means,
- emitter structure means comprising cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device.
5 more elements
A photocathode device for absorbing a photon and emitting one or a plurality of electrons comprising
- detector structure means for absorbing the photon and creating an electron-hole pair,
- voltage means for creating electric fields within and outside the device to separate the electron from the hole and aid in electron emission
- electrical contacts and shields to create and shape the electric fields from the voltage means,
- emitter structure means comprising
- cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device, wherein the emitter structure means is composed of cone-shaped emitters which are greater than 3 μm and less than 20 μm tall.
2 more elements
A photocathode device for absorbing a photon and emitting one or a plurality of electrons comprising
- detector structure means for absorbing the photon and creating an electron-hole pair,
- voltage means for creating electric fields within and outside the device to separate the electron from the hole and aid in electron emission
- electrical contacts and shields to create and shape the electric fields from the voltage means,
- emitter structure means comprising
- cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device, wherein a layer of material is deposited on all or part of the emitter structure.
2 more elements
A device for imaging a source of x-ray or gamma-ray photons comprising
- one or a plurality of sensors for absorbing gamma-ray or x-ray photons producing amplified light photon signals for each x-ray or gamma-ray photons
- optics to focus the light photons on detector means in output electronics
- said output electronics converting the light photon signals into electrical signals and to digitize the electrical signals,
- drive electronics to control the integration time of the sensor and control the transfer of signals from the output electronics to the data storage and display circuitry,
- data storage and display circuitry to display and store the x-ray or gamma-ray source image,
- said sensors comprising
- a photocathode device for absorbing the photon and emitting one or a plurality of electrons,
- amplification means to increase the photon signal
- said photocathode device comprising
- detector structure means for absorbing the photons and creating one or a plurality of electron-hole pairs,
- voltage means for creating electric fields within and outside the device to separate the electrons from the holes and aid in electron emission
- electrical contacts and shields to create, shape and amplify the electric fields from the voltage means,
- emitter structure means comprising cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device.
10 more elements
A device for imaging a source of x-ray or gamma-ray photons comprising
- one or two sensors for absorbing gamma-ray or x-ray photons producing amplified light photon signals for each x-ray or gamma-ray photon,
- optics to focus the light photons on an eye,
- said sensor comprising
- a photocathode device for absorbing the photons and emitting one or a plurality of electrons,
- amplification means to increase the photon signals
- said photocathode device comprising
- detector structure means for absorbing the photons and creating one or a plurality of electron-hole pairs,
- voltage means for creating electric fields within and outside the device to separate the electrons from the holes and aid in electron emission
- electrical contacts and shields to create, shape and amplify the electric fields from the voltage means,
- emitter structure means comprising cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device.
7 more elements
A photocathode device for absorbing a photon and emitting one or a plurality of electrons comprising
- detector structure means for absorbing the photon and creating an electron-hole pair,
- voltage means for creating electric fields within and outside the device to separate the electron from the hole and aid in electron emission
- electrical contacts and shields to create and shape the electric fields from the voltage means,
- emitter structure means comprising
- cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device,
- wherein the detector structure means is Mercury Cadmium Telluride.
3 more elements
A photocathode device for absorbing a photon and emitting one or a plurality of electrons comprising
- detector structure means for absorbing the photon and creating an electron-hole pair,
- voltage means for creating electric fields within and outside the device to separate the electron from the hole and aid in electron emission
- electrical contacts and shields to create and shape the electric fields from the voltage means,
- emitter structure means comprising
- cone-shaped emitters to transfer the electron from the inside of the device to the outside of the photocathode device,
- wherein the detector structure means is Germanium.
3 more elements
A device for resolving a flux of x-ray or gamma-ray photons, which has an energy spectrum, into one or a plurality of energy intervals, for determining the quantity of flux in each energy interval and for storing and displaying the results comprising
- one or a plurality of sensors for absorbing the flux of photons and for producing separate electrical signals representative of the energy of photons absorbed on said sensors
- drive electronics to control an integration time of a sensor and to control the transfer of signals to output electronics and to data storage and display circuitry
- said output electronics associating the photon signals with energy intervals, and converting the photon signals to digital signals and to count the flux of photons in each energy interval
- data storage and display circuitry to store count information from said output electronics and to display the count information
- said sensor comprising
- a photocathode device for absorbing a portion of the photon flux and emitting one or a plurality of electrons,
- an amplifier to multiply the number of electrons from said photocathode device and
- readout electronics associating the electrons from the amplifier with an electrical signal
- said photocathode device comprising
- a detector structure that absorbs the photon flux and creates one or a plurality of electron-hole pairs,
- one or more voltage sources creating electric fields within and outside the device that separate the electrons from the holes
- electrical contacts and shields to create, shape and amplify the electric fields from the voltage means,
- emitters to transfer the electrons from the inside of the device to the outside of the photocathode device.
10 more elements
Dependencies are inferred from the claim text.