1. A method of enhancing image quality and providing tissue composition information by analysis of energy discrimination data, the method comprising:
determining a radiation dosage at one or more energy spectrum levels based on patient parameters and user selected parameters.
2. The method of claim 1, wherein the determining step comprises:
acquiring patient parameters;
receiving user selected parameters;
selecting system acquisition settings based on the patient parameters and the user selected parameters;
acquiring image data from the patient based on the selected settings; and
processing the image data.
3. The method of claim 2, wherein the patient parameters are representative of estimates of patient size, shape, and anatomy being imaged.
4. The method of claim 2, wherein the user selected parameters are representative of image diagnostic exam type and visualization mode.
5. The method of claim 2, wherein the selecting step further comprises determining system acquisition settings from multi-dimensional look-up tables based on the patient parameters and the user selected parameters.
6. The method of claim 5, wherein the system acquisition settings comprise a desirable scan rate, a source filter material and thickness, a tube voltage, a current, or combinations thereof.
7. The method of claim 5, further comprising estimating incident flux for each view and each energy bin.
8. The method of claim 2, wherein the processing step comprises:
correcting the acquired image data;
weighting energy bin values to achieve higher contrast-to-noise or composition information;
reconstructing an image using corrected image data to generate a reconstructed image;
correcting image data using the reconstructed image;
applying post-processing algorithms to the reconstructed image to generate a final image; and
presenting the final image to user.
9. The method of claim 8, where the correcting the acquired image data step comprises:
acquiring image data from a first region of a pixel, wherein the first region has a first area;
acquiring image data from a second region of the pixel, wherein the second region has a second area; and
combining image data from the first and second regions to obtain composite image data for the pixel.
10. The method of claim 9, wherein each of the first and second regions is configured to count photons received and associate an energy bin to each photon counted.
11. The method of claim 9, further comprising calibrating the image data from each of the first and second regions to generate calibrated data.
12. The method of claim 11, wherein calibrating the image data comprises:
measuring detected charge as a function of input X-ray flux; and
fitting the detected charge to a polynomial function.
13. The method of claim 12, wherein the fitting step comprises correcting pile-up effects, non-ideal detector response characteristics or both in the image data acquired from each of the first and second regions.
14. The method of claim 9, wherein the combining step comprises combining the image data from the first and second regions weighted inversely by associated noise variance.
15. A system for enhancing image quality and providing tissue composition information by analysis of energy discrimination data, the system configured to determine a radiation dosage at one or more energy spectrum levels based on patient parameters and user selected parameters, wherein the system is configured to:
acquire patient parameters;
receive user selected parameters;
select system acquisition settings based on the patient parameters and the user selected parameters, by determining the system acquisition settings from multi-dimensional look-up tables based on the patient parameters and the user selected parameters, and wherein the system acquisition settings comprise a desirable scan rate, a source filter material and thickness, a tube voltage, a current or combinations thereof;
acquire image data from the patient based on the selected settings; and
process the image data.
16. A system for enhancing image quality and providing tissue composition information by analysis of energy discrimination data, the system configured to determine a radiation dosage at one or more energy spectrum levels based on patient parameters and user selected parameters.
17. The system of claim 16, wherein the system is configured to:
acquire patient parameters;
receive user selected parameters;
select system acquisition settings based on the patient parameters and the user selected parameters;
acquire image data from the patient based on the selected settings; and
process the image data.
18. The system of claim 17, wherein the patient parameters are representative of estimates of patient size, shape, and anatomy being imaged.
19. The system of claim 17, wherein the user selected parameters representative of image diagnostic exam type and visualization mode.
20. The system of claim 17, wherein the system acquisition settings comprise a desirable scan rate, a source filter material and thickness, a tube voltage, a current, or combinations thereof.
21. The system of claim 17, wherein the control system is further configured to determine system acquisition settings from multi-dimensional look-up tables based on the patient parameters and user selected parameters.
22. A computer readable medium comprising one or more tangible media, wherein the one or more tangible media comprise:
code adapted to determine a radiation dosage at one or more energy spectrum levels based on patient parameters and user selected parameters.
23. The computer readable medium, as recited in claim 22, wherein the code adapted to determine a radiation dosage comprises:
code adapted to acquire patient parameters;
code adapted to receive user selected parameters;
code adapted to select system acquisition settings based on the patient parameters and the user selected parameters;
code adapted to acquire image data from the patient based on the selected settings; and
code adapted to process the image data.
24. A radiographic imaging system comprising:
a radiation source configured to emit a stream of radiation toward a patient to be scanned;
a control system configured to enhance image quality and providing tissue composition information by analysis of energy discrimination data by determining a radiation dosage based on patient parameters and user selected parameters;
a detector assembly configured to detect the stream of radiation and to generate one or more signals responsive to the stream of radiation, wherein the detector assembly comprises one or more detectors configured to absorb radiation;
a system controller configured to rotate the radiation source and the detector assembly and to acquire one or more sets of projection data from the one or more detectors via a data acquisition system; and
a computer system operationally coupled to the radiation source and the detector assembly, wherein the computer system is configured to receive the one or more sets of projection data.
25. The system of claim 24, wherein the control system is configured to:
acquire patient parameters;
receive user selected parameters;
select system acquisition settings based on the patient parameters and the user selected parameters;
acquire image data from the patient based on the selected settings; and
process the image data.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An optical module comprising:
an amplification optical fiber amplifying light to be amplified by supply of pumping light, said amplification optical fiber including:
a core extending along a predetermined axis and being doped with an amplification dopant for amplifying the light to be amplified;
a first cladding provided on an outer periphery of said core and having a refractive index lower than that of said core;
a second cladding provided on an outer periphery of said first cladding and having a refractive index lower than that of said core; and
a third cladding provided on an outer periphery of said second cladding and having a refractive index lower than those of said first and second claddings, whereby said amplification optical fiber allows light to be amplified to propagate in a single-mode in said core thereof and allows the pumping light to propagate in a multi-mode in said core, said first cladding, and said second cladding thereof;
an optical coupler optically connected to one end of said amplification optical fiber, said optical coupler supplying at least the pumping light into said amplification optical fiber; and
an absorption optical fiber optically connected to the other end of said amplification optical fiber and absorbing the pumping light having passed through said amplification optical fiber, said absorption optical fiber including:
a core extending along a predetermined axis so as to be optically connected to said core of said amplification optical fiber;
a first cladding provided on an outer periphery of said core of said absorption optical fiber so as to be optically connected to said first cladding of said amplification optical fiber, and having a refractive index lower than that of said core of said absorption optical fiber;
a second cladding provided on an outer periphery of said first cladding of said absorption optical fiber so as to be optically connected to said second cladding of said amplification optical fiber, and having a refractive index lower than that of said core of said absorption optical fiber, said second cladding of said absorption optical fiber being doped with an absorption dopant for absorbing the pumping light; and
a third cladding provided on an outer periphery of said second cladding of said absorption optical fiber and having a refractive index lower than those of said first and second claddings of said absorption optical fiber, whereby said absorption optical fiber allows light to be amplified to propagate in a single-mode in said core thereof and allows the pumping light to propagate in a multimode in said core, said first cladding, and said second cladding thereof.
2. An optical module according to claim 1, wherein said first cladding of said amplification optical fiber is a region in which no amplification dopant is intentionally doped.
3. An optical module according to claim 1, wherein the amplification dopant includes Yb and the absorption dopant includes Er.
4. An optical module according to claim 3, wherein an Er doping concentration in said second cladding of said absorption optical fiber is 1000 wt.ppm or more but 8000 wt.ppm or less.
5. An optical module according to claim 1, wherein said core of said absorption optical fiber is comprised of pure silica.
6. An optical module according to claim 1, wherein said first cladding of said absorption optical fiber is a region in which no amplification dopant is intentionally doped.
7. An optical module according to claim 1, wherein said core of said absorption optical fiber is a region in which no absorption dopant is intentionally doped.
8. An optical module according to claim 1, wherein one end of said absorption optical fiber is connected to one end portion, from which the pumping light is outputted, of both end portions of said amplification optical fiber, and
wherein a single-mode optical fiber is disposed on a propagation path of the light to be amplified having passed through both of said amplification optical fiber and said absorption optical fiber, said single-mode optical fiber including:
a core allowing the light to be amplified to propagate in a single-mode; and
a cladding provided on an outer periphery of said core and having a refractive index lower than that of said core, said cladding preventing the pumping light from propagating.
9. An optical module according to claim 1, wherein said first cladding of said absorption optical fiber is doped with the absorption dopant.
10. A method of processing a predetermined target using an optical module according to claim 1, said method comprising the steps of:
setting the target in a predetermined position;
supplying the pumping light via said optical coupler into said amplification optical fiber through which the light to be amplified propagates; and
irradiating the target with amplified light taken out from said optical module via an optical system for condensing the amplified light.
11. A method according to claim 10, wherein said amplification optical fiber and said absorption optical fiber are disposed in sequence along the traveling direction of the light to be amplified, and said optical coupler is disposed to said amplification optical fiber such that the light to be amplified and the pumping light propagate in the same direction; and
wherein visible light obtained by upconversion of the pumping light in said absorption optical fiber is irradiated onto the target via said optical system.