CN101632591B - Radiograph and image processing program - Google Patents

Abstract

A radiograph is characterized in that the image processing means has acquiring means for acquiring the projection data on the first energy spectrum and the projection data on the second energy spectrum, synthesis image creating means for combining a first image formed from the projection data on the first energy spectrum and a second image formed from the projection data on the second energy spectrum under a predetermined combining condition, and synthesizing a synthesis image and that the display means displays the synthesis image.

Description

Radiographic equipment and image processing program

The present invention's application number that to be applicant Hitach Medical CO LTD propose on May 12nd, 2006 be 200680016705.6, denomination of invention divides an application for " radiographic equipment and image processing program " patent application.

Technical field

The present invention relates to radiographic equipment and image processing program, relate in particular to generating higher meticulous layer image useful technology according to the data that adopt a plurality of X heat inputs to gather.

The application follows based on the patent application of Japan Patent method is special to be willing to 2005-145166 number and to be willing to the application of Paris claim of priority of 2005-232060 number based on the spy, is specially to be willing to 2005-145166 number and specially to be willing to 2005-232060 number interests and to accept to quote the application of reference in order to enjoy.

Background technology

The multipotency CT (multienergy CT) that shines two kinds of X lines with different power spectrums is disclosed in the patent documentation 1.When the X line with spectral width sees through subject, because low-energy X line is absorbed mostly, therefore so-called beam sclerosis (beamhardening) effect that energy peak moves to high lateral deviation can take place.The precision that known beam hardening effect can cause pseudomorphism (artifact) or CT value take place worsens.In multipotency CT, utilize the data of gathering from two kinds of power spectrums, can realize good beam sclerosis correction, therefore think and can reduce the pseudomorphism situation that causes by the beam sclerosis, can expect to improve the precision of CT value.

In addition, in multipotency CT, owing to can obtain to represent the data that decay respectively because of Compton effect and photoelectric effect, therefore think the image that can generate expression atom numbering and density, thereby can expect application such as the bone that in the CT of the type of shining a kind of power spectrum, is difficult to realize and separating of radiography blood vessel.

Patent documentation 1: the spy opens the 2004-188187 communique

When using polyenergetic and have the CT of X line of spectral width, can produce various pseudomorphisms such as obfuscation or striped because of the beam hardening effect.In addition, owing to only use a kind of X line of power spectrum, so there is limit in the correction precision of beam hardening effect.Because in CT based on homogeneous radiation light, the beam hardening phenomenon can not take place, therefore be difficult for producing pseudomorphism, thereby have advantage aspect the precision of CT value and the picture contrast.

But, need expensive and large-scale devices such as cyclotron in order to produce monochromatic x-ray, therefore be difficult to extensive use in clinical, its application is limited in the limited scope.In multipotency CT, wait in expectation according to the data that obtain by a plurality of power spectrums application such as effective correction of correlation beam hardening effect and bone and separating of radiography blood vessel.But, use fully research such as the trial that especially improves picture contrast for other.

Summary of the invention

The objective of the invention is to, a kind of radiographic equipment and image processing program that can generate the higher meticulous and layer image that contrast is excellent according to the data of utilizing a plurality of power spectrum collections is provided.

In order to address the above problem, radiographic equipment of the present invention comprises: the X line source, and it shines the X line of first power spectrum and the X line of second power spectrum; The X thread detector, it detects the X line of described first power spectrum that sees through subject and the X line of second power spectrum, and exports the data for projection of first power spectrum and the data for projection of second power spectrum; Control unit, its action to described X line source and described X thread detector is controlled; Graphics processing unit, it generates desirable image based on the data for projection of described first power spectrum and the data for projection of second power spectrum; And display unit, it shows described image; Wherein, described graphics processing unit comprises: obtain the unit, it obtains the data for projection of described first power spectrum and the data for projection of second power spectrum; With the synthesized image generation unit, its will based on first image of the data for projection of described first power spectrum, with second image based on the data for projection of described second power spectrum, synthesis condition according to the rules synthesizes and generates synthesized image; Described display unit shows the synthesized image after the described generation.

And image processing program of the present invention makes computer carry out following steps: read in step, read in the data for projection of the X line of the data for projection of X line of first power spectrum that has seen through subject and second power spectrum; And synthesis step, synthesis condition according to the rules to synthesizing based on first image of the data for projection of described first power spectrum with based on second image of the data for projection of described second power spectrum, generates synthesized image.

Here, comprise in " based on first image of the data for projection of described first power spectrum " as the projection image of the data for projection of first power spectrum and the reconstructed image that obtains by these data for projection of reconstruct (being projection image).Equally, comprise in " based on second image of the data for projection of second power spectrum " as the projection image of the data for projection of second power spectrum and the reconstructed image that obtains by these data for projection of reconstruct.

And, when definition " first power spectrum ", " second power spectrum ", except at least one of characteristic quantities such as the shape of the power spectrum of utilizing the X line, area, wave height, highest energy, minimum energy defines the situation of power spectrum, also comprise the situation of utilizing the effective energy corresponding to define power spectrum with this power spectrum.And then, when definition " first power spectrum ", " second power spectrum ", can distinguish with other power spectrums and get final product, also comprise above-mentioned characteristic quantity of unfavorable usefulness or effective energy, and only by marking the situation that labelling (for example, first, second etc.) defines.

(invention effect)

According to the present invention, has following effect: in X computer on line tomography, can generate higher meticulous and layer image that contrast is excellent according to the data of utilizing a plurality of power spectrums to gather.

Description of drawings

Fig. 1 is the pie graph of x-ray ct device of the present invention;

Fig. 2 is the key diagram that generates the method for synthesized image according to the reconstructed image that the data for projection by a plurality of power spectrum collections generates;

Fig. 3 is the flow chart of the handling process of explanation the 1st embodiment;

Fig. 4 is the key diagram of definite method of the blending ratio in the 1st embodiment;

Fig. 5 is the flow chart of the handling process of explanation the 2nd embodiment;

Fig. 6 is the key diagram of definite method of the blending ratio in the 2nd embodiment;

Fig. 7 is the flow chart of the handling process of explanation the 3rd embodiment;

Fig. 8 is the summary pie graph of x-ray ct device 1;

Fig. 9 is the pie graph of the image processing part 105 of x-ray ct device 1;

Figure 10 is the curve chart of the Energy distribution of expression X line;

Figure 11 is expression changes the method for imaging that X line effective energy photographs by each scanning figure;

Figure 12 is the figure that is illustrated in the method for imaging that change X line effective energy is photographed in the single pass;

Figure 13 is the irradiation position among Figure 11 and Figure 12 and the graph of a relation of X line effective energy;

Figure 14 is the figure of expression color with respect to the ratio of image;

Figure 15 is the corresponding diagram of X line effective energy (X ray tube voltage) and ratio color frequency (ratio color);

Figure 16 is the figure (combined color image generate handle) of the handling process in the image processing part 105 of expression x-ray ct device 100;

Figure 17 is the flow chart (combined color image generate handle) of action of the image processing part 105 of expression x-ray ct device 100;

Figure 18 is the figure (difference combined color image generate handle) of the handling process in the image processing part 105 of expression x-ray ct device 100;

Figure 19 is the flow chart (difference combined color image generate handle) of action of the image processing part 105 of expression x-ray ct device 100;

Figure 20 is the figure (emphasize that image generate handle) of the handling process in the image processing part 105 of expression x-ray ct device 100;

Figure 21 is the flow chart (emphasize that image generate handle) of action of the image processing part 105 of expression x-ray ct device 100;

Figure 22 is that the existing data operation of expression is handled the figure of (indivedual calculation process);

Figure 23 is that expression data operation of the present invention is handled the figure of (gathering calculation process);

Figure 24 is the curve chart of the relation of expression photon energy and X linear absorption coefficient;

Figure 25 is the curve chart (to the number space) of the relation of expression photon energy and X linear absorption coefficient;

Figure 26 is the figure of the establishing method of expression Filtering Processing parameter;

Figure 27 is the figure of the control of the expression scanning speed corresponding with X line effective energy;

Figure 28 is the irradiation position among Figure 27 and the graph of a relation of X line effective energy and scanning speed;

Figure 29 is the figure of the control of the expression x-ray tube current corresponding with X line effective energy;

Figure 30 is the irradiation position among Figure 29 and the graph of a relation of X line effective energy and x-ray tube current;

Figure 31 is the figure of the control of the several ratio in expression the find a view position (view) corresponding with X line effective energy;

Figure 32 is the irradiation position among Figure 31 and the graph of a relation of the X line effective energy and the positional number of finding a view;

Figure 33 is the figure of expression X spool device 107;

Figure 34 is the approximate three-dimensional map of target 1137;

Figure 35 is the figure of a form (target 1137a) of expression target 1137;

Figure 36 is the figure of a form (target 1137b) of expression target 1137;

Figure 37 is the curve chart of expression Energy distribution of X line when having utilized the different target of material;

Figure 38 is the figure of a form of expression X thread detector 127;

Figure 39 is that the picture of the affirmation picture of parameter, power spectrum and effective energy shows example.

Among the figure: 1-X line CT device; 2-stand (gantry); The 3-X line source; The 4-collimator; The 5-detector array; The 6-detector element; The 7-X line; The 8-center of rotation; The 9-control part; 10-X line traffic control unit; 11-stand control unit; 12-DAS; The 13-graphics processing unit; The 14-reconfiguration unit; The 15-blending ratio is calculated the unit; 16-synthesized image generation unit; 17-preserves the unit; The interim storage element of 18-; The 19-input block; The 20-image-display units; 100-X line CT device; The 103-scanner section; The 105-image processing part; 107-X spool device; The 119-subject; The 127-X thread detector; The 137-control part; The 139-storage device; The 141-display part; 145-input and output portion; The 149-photon energy; The 151-energy intensity; 153,155,157-energy curve; 161,169-scanning (photography); The 163-irradiation position; The 165-X line; The 167-image; The 174-color; The 175-mono-color image; The 177-combined color image; 183-handles image; The 185-difference image; 187-difference mono-color image; 189-difference combined color image; 191-emphasizes image; 193,199-data for projection; The computing of 195-image reconstruction; 197,1101-reconstructed image data; 1107,1120-curve (X linear absorption coefficient); 1115,1127-error; 1129,1131,1133-wave filter; The 1135-scanning speed; 1137,1137a, 1137b-target (anode); The 1138-impingement area; 1139-electron gun (negative electrode); The 1141-deflector; The 1143-electron beam; The 1145-X line; 1149,1151-energy curve; The 1157-X line; The 1159-data for projection.

The specific embodiment

Below, with reference to the accompanying drawings, the preferred implementation of x-ray ct device of the present invention is elaborated.

(the 1st embodiment)

Fig. 1 is the figure of the preferred implementation of expression radiographic equipment of the present invention (hereinafter referred to as " x-ray ct device ").X-ray ct device 1 of the present invention comprises stand 2, and stand 2 has X line source 3, collimator 4 and the detector array 5 on the opposed faces that is positioned at stand 2.Detector array 5 is formed by detector element 6, and this detector element 6 detects the X line that sees through the subject on the not shown pedestal.Detector element 6 is configured to line shape or a plurality of side by side line shape.Each detector element 6 produce the incident X line beam of expression intensity, be the signal of telecommunication of the decay of X line beam when seeing through subject.Under the state of X line source 3 exposures 7, stand 2 is the center rotation with center of rotation 8, can gather X line projection data thus.Stand 2 and X line source 3 are by control part 9 controls of x-ray ct device 1.Control part 9 comprises X line traffic control unit 10, stand control unit 11 and DAS (data collecting system) 12, is transformed to digital signal from the analogue signal of detector element 6 by DAS12.X line data behind the digitized are reconstructed by the reconfiguration units 14 in the graphics processing unit 13, and are stored in the preservation unit in the graphics processing unit 13.Graphics processing unit 13 is arithmetic processing apparatus such as computer, and comprising: blending ratio is calculated unit 15, and its calculating is carried out blended ratio to the reconstructed image based on each power spectrum; Synthesized image generation unit 16, it generates synthesized image based on calculated the blending ratio of calculating the unit by blending ratio; Hard disks etc. are preserved unit 17; Interim storage element 18 such as memorizer; Input block such as mouse or keyboard 19.In addition, also possess among not shown Digital Signal Processor (DSP) or Micro Processor Unit (MPU), the Central Processing Unit (CPU) at least one.Image-display units 20 is and graphics processing unit 13 integrated or independently display devices such as display.In Fig. 1, control part 9 and operation processing unit 13 are separated, but both also can be integrated.In addition, reconfiguration unit 14 also can be independent with graphics processing unit 13.

Fig. 2 is in the embodiment of expression x-ray ct device 1 of the present invention, and the reconstructed image that generates according to the data for projection by a plurality of power spectrum collections generates the sketch map of the method for synthesized image.Based on reconstructed image that generates by the data for projection of the first power spectrum collection (hereinafter referred to as " first reconstructed image ") and the reconstructed image (hereinafter referred to as " second reconstructed image ") that generates by the data for projection of the second power spectrum collection, calculate blending ratio, generate synthesized image based on this blending ratio then.In Fig. 2, calculate blending ratio w according to first reconstructed image, first reconstructed image is mixed with the ratio of (1-w) with the ratio of blending ratio w and to second reconstructed image.Though calculate blending ratio according to first reconstructed image above, blending ratio also can be calculated according to second reconstructed image, also can calculate according to both sides' reconstructed image.In Fig. 2, for the purpose of simplifying the description, represented example, but also can gather by the power spectrum more than three by two power spectrum recording projection datas.

Fig. 3 is in the embodiment 1 of x-ray ct device of the present invention, collects handling process till synthesized image shows from data for projection.

In step S301, recording projection data (S301) at first.X-ray ct device 1 is the CT device of multipotency mode, and for example the repeatedly scanning of moving with a plurality of current potentials such as 80kVp and 120kVp is carried out by continous way or interlacing formula, thus recording projection data.Perhaps, the special wave filter of configuration makes various detector columns gather the data for projection of various power spectrums between X line source 3 and detector element 6.Perhaps, can realize the CT device of multipotency mode by using energy sensing type detector.

In step S302, reconfiguration unit 14 generates reconstructed image (S302) at the data for projection of various power spectrums.DAS12 gathers the data for projection (hereinafter referred to as " second data for projection ") by the X line of the data for projection (hereinafter referred to as " first data for projection ") of the X line of detector array 5 detected first power spectrums and second power spectrum, and sends to graphics processing unit 13.Graphics processing unit 13 is obtained first data for projection and second data for projection, and reconfiguration unit 14 generates first reconstructed image based on first data for projection.Equally, generate second reconstructed image based on second data for projection.

In step S303, blending ratio is calculated unit 15 and is calculated blending ratio (S303).Calculation method to blending ratio will be described later.

In step S304, synthesized image generation unit 16 is calculated pixel value (S304) after synthetic based on the blending ratio that is obtained.Pixel value after synthetic is calculated according to following mathematical expression 1.

[mathematical expression 1]

OIMG＝w·IMG ₁+(1-w)·IMG ₂...(1)

Here, OIMG represents synthesized image, pixel value in second reconstructed image that pixel value in first reconstructed image that IMG1 represents to generate according to the data for projection by the first power spectrum collection, IMG2 are represented to generate according to the data for projection by the second power spectrum collection, w represents blending ratio.In addition, w is the real number between 0～1.Carry out S303～304 repeatedly by each pixel or by each regional area.

In step S305, synthesized image generation unit 16 generates synthesized image (S305) by the pixel value behind synthetic in each pixel of calculating or each regional area is shone upon (mapping).

In step S306, image-display units 20 shows the synthesized image (S306) that is generated.

Below, the calculation method of blending ratio in the embodiment 1 of x-ray ct device of the present invention is described.The CT value generally has because of the different value of tissue.For example, bone has the CT value about 1000HU, and internal organs such as liver and brain have the CT value about 25～80HU, and fat has-CT value about 100HU, and lung field has-CT value about 800HU.Internal organs such as known brain exist the low more tendency that can absorb the X line more better of energy of irradiated X line, and bone etc. exist the energy of irradiated X line and get over the tendency that Gao Yueneng absorbs the X line better.Here, set the effective energy of first power spectrum lower, the effective energy of second power spectrum is set under the condition with higher, have the low more position that can absorb the tendency of X line more better of energy, the composition of the reconstructed image that is generated by the data for projection of the first power spectrum collection is strengthened; Get over the position that Gao Yueneng absorbs the tendency of X line better having energy, the composition of the reconstructed image that is generated by the data for projection of the second power spectrum collection is strengthened, and mix, can obtain the good synthesized image of contrast thus.That is, for example setting blending ratio as shown in Figure 4 generates synthesized image and gets final product.The curve chart of Fig. 4 is by 2 expressions of following mathematical expression.

[mathematical expression 2]

$\left\{\begin{array}{cc}t\&le;\mathrm{TH}1& w=0\\ \mathrm{<figure-callout\; id="1"\; label="TH"\; filenames="H2009101511126E00021.png,H2009101511126E00241.png"\; state="\{\{state\}\}">TH</figure-callout>}1\&le;t\&le;\mathrm{TH}2& w=\mathrm{TH}7/{(\mathrm{TH}2-\mathrm{TH}1)}^2\&CenterDot;{(t-\mathrm{TH}1)}^2\\ \mathrm{<figure-callout\; id="2"\; label="TH"\; filenames="H2009101511126E00241.png"\; state="\{\{state\}\}">TH</figure-callout>}2\&le;t\&le;\mathrm{TH}3& w=\sin (\frac{\mathrm{\&pi;}}{2(\mathrm{TH}3-\mathrm{TH}2)}\&CenterDot;(t-\mathrm{TH}2))\\ \mathrm{TH}3\&le;t\&le;\mathrm{TH}4& w=1\\ \mathrm{TH}4\&le;t\&le;\mathrm{TH}5& w=\cos (\frac{\mathrm{\&pi;}}{2(\mathrm{TH}5-\mathrm{TH}4)}\&CenterDot;(t-\mathrm{TH}4))\\ \mathrm{<figure-callout\; id="5"\; label="TH"\; filenames="H2009101511126E00011.png"\; state="\{\{state\}\}">TH</figure-callout>}5\&le;t\&le;\mathrm{TH}6& w=\mathrm{TH}7/{(\mathrm{TH}5-\mathrm{TH}6)}^2\&CenterDot;{(t-\mathrm{TH}6)}^2\\ \mathrm{TH}6\&le;t& w=0\end{array}\right.\&CenterDot;\&CenterDot;\&CenterDot;\left(2\right)$

Here, wish that TH1 is about-1000, TH2 for about-200, TH3 for about-100, TH4 for about+80, TH5 for about+160, TH6 is about+1000, wishes that TH7 is about 0.1.Blending ratio is not limited to the example shown in Fig. 4 and the mathematical expression 2, as long as the composition according to first reconstructed image that is generated by first data for projection of the first power spectrum collection is strengthened having the low more position that can absorb the tendency of X line more better of energy, getting over the position that Gao Yueneng absorbs the tendency of X line better and make the composition of second reconstructed image that generates according to second data for projection by the second power spectrum collection strengthen such blending ratio having energy, then can be curve shape and mathematical expression arbitrarily.

According to present embodiment, in first reconstructed image and second reconstructed image, can be according to pixels or generate synthesized image by the blending ratio that regional area improves the higher reconstructed image of contrast.

In addition, in the above-mentioned embodiment, in S302, generate after first reconstructed image and second reconstructed image, in S303, calculate blending ratio, in S304, calculate with first reconstructed image and second reconstructed image pixel value after synthetic, but also can generate in accordance with regulations blending ratio with first data for projection and the mixed mixing data for projection of second data for projection, this mixing data for projection is reconstructed the back generate blended synthesized image (reconstructed image).Under this situation, according to the composition of first data for projection of being gathered by first power spectrum being strengthened having the low more position that can absorb the tendency of X line more better of energy, get over the enhanced mode of composition that position that Gao Yueneng absorbs the tendency of X line better makes second data for projection of being gathered by second power spectrum having energy, set blending ratio.

(the 2nd embodiment)

Fig. 5 is in second embodiment of x-ray ct device of the present invention, collects handling process till synthesized image shows from data for projection.

In step S501, recording projection data (S501) at first.Method and the 1st embodiment about data acquisition get final product equally.

In step S502, reconfiguration unit 14 generates first reconstructed image and second reconstructed image (S502) at the data for projection of each power spectrum.

In step S503, blending ratio is calculated effective atom numbering (S503) that concerned pixel or regional area are calculated in unit 15.Blending ratio is calculated unit 15 and is cut apart (segmentation) first reconstructed image and second reconstructed image by the tissue with same living body functional.In multipotency CT, replace as the CT of existing type obtain whole attenuation quotient, and obtain a pair of image that the decay of handling from contrast and photoelectricity is separately represented, thereby can obtain that effective atom is numbered and the information of density.If utilize this character, then can obtain by each tissue or by each concerned pixel, number by effective atom of each regional area.

In step S504, blending ratio is calculated unit 15 based on the effective atom numbering that obtains in S503, obtain X line absorption end (S504).X line absorption characteristic is the inherent characteristic of material, effectively atom numbering and corresponding one by one by the X line absorption end of the material of this atomic building.Therefore, if understand effective atom numbering, then can hold the pairing X line absorption of this material end.In order to finish S504 at short notice, wish to generate in advance the correspondence table of material and X line absorption end, and with reference to this table.

In step S505, blending ratio is calculated unit 15 and is calculated blending ratio (S505).Calculation method to blending ratio will be described later.

In step S506, synthesized image generation unit 16 is calculated pixel value (S506) after synthetic based on the blending ratio that obtains in S505.The calculation method and the 1st embodiment of the pixel value after synthetic get final product equally.Synthesized image generation unit 16 is carried out S503～506 repeatedly by each pixel or by each regional area.

In step S507, synthesized image generation unit 16 generates synthesized image (S507) by the pixel value behind synthetic in each pixel of calculating among the S506 or each regional area is shone upon.

In step S508, image-display units 20 is presented at the synthesized image (S508) that generates among the S507.

Below, utilize Fig. 6, the calculation method of blending ratio in the 2nd embodiment of x-ray ct device of the present invention is described.Here, at setting the effective energy of first power spectrum lower, setting the effective energy of second power spectrum to such an extent that condition with higher describes.If the effective energy of first power spectrum is E _1st, first power spectrum effective energy be E _2ndIn addition, the X line absorption end of establishing material in concerned pixel or the regional area is E _ROIAt this moment, blending ratio w is calculated by following formula.

[mathematical expression 3]

$\left\{\begin{array}{c}w=(1-t)\&CenterDot;{\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009101511126E00021.png,H2009101511126E00241.png"\; state="\{\{state\}\}">E</figure-callout>}}_{1\mathrm{st}}+t\&CenterDot;{\mathrm{<figure-callout\; id="2"\; label="E"\; filenames="H2009101511126E00241.png"\; state="\{\{state\}\}">E</figure-callout>}}_{2\mathrm{nd}}\\ t=\frac{E_{\mathrm{ROI}}-{\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="H2009101511126E00021.png,H2009101511126E00241.png"\; state="\{\{state\}\}">E</figure-callout>}}_{1\mathrm{<figure-callout\; id="1"\; label="st\; E"\; filenames="H2009101511126E00021.png,H2009101511126E00241.png"\; state="\{\{state\}\}">st</figure-callout>}}}{E_{}}\end{array}\right.\&CenterDot;\&CenterDot;\&CenterDot;\left(3\right)$

In the present embodiment, at setting the effective energy of first power spectrum lower, set the effective energy of second power spectrum to such an extent that condition with higher is illustrated, but to those skilled in the art, can easily understand also can be situation in contrast to this.

(the 3rd embodiment)

Fig. 7 is in the 3rd embodiment of x-ray ct device of the present invention, collects handling process till synthesized image shows from data for projection.

In step S701, recording projection data (S701) at first.Get final product equally about the method for data acquisition and the 1st embodiment and the 2nd embodiment.

In step S702, reconfiguration unit 14 generates first reconstructed image and second reconstructed image (S702) at the data for projection of each power spectrum.

In step S703, blending ratio is calculated the local standard deviation of pixel value of calculating the concerned pixel periphery in unit 15 or the local standard deviation (S703) of regional area.

In step S704, blending ratio is calculated the local standard deviation (SD1) of first reconstructed image that the 15 pairs of bases in unit generate by the data for projection of the first power spectrum collection and the local standard deviation (SD2) of second reconstructed image that generates according to the data for projection by the second power spectrum collection compares (S704).When SD1 than SD2 hour, select the first reconstructed image Img1 (S705) that generates according to data for projection by the first power spectrum collection.In addition, in S704, when SD1 is bigger than SD2, select the second reconstructed image Img2 (S706) that generates according to data for projection by the second power spectrum collection.

In step S707, concerned pixel in the reconstructed image that synthesized image generation unit 16 will be selected in S705 and 706 or the pixel value in the regional area are set at the pixel value (S707) after synthesizing.Synthesized image generation unit 16 is carried out S703～707 repeatedly by each pixel or by each regional area.

In step S708, synthesized image generation unit 16 generates synthesized image (S708) by the pixel value behind synthetic in each pixel of calculating among the S707 or each regional area is shone upon.

In step S709, image-display units 20 shows the synthesized image (S709) that is generated.

According to present embodiment, can from first reconstructed image and second reconstructed image, select picture noise image still less to generate synthesized image.Therefore, can generate and the few synthesized image of display image noise, help to improve diagnosis capability.

(the 4th embodiment)

The 4th embodiment is used to illustrate the mode that obtains data for projection from a plurality of X lines with different power spectrums or effective energy.Wherein, will be that example describes with a plurality of X lines with different effective energies, but when a plurality of X lines that utilization has different power spectrums are photographed too.

Fig. 8 is the summary pie graph of x-ray ct device 100.

X-ray ct device 100 is made of scanner section 103 and image processing part 105.

X-ray ct device 100 is devices of taking subject 119 and exporting photographed images.X-ray ct device 100 is taken subject 119 by scanner section 103, carries out Flame Image Process and export photographed images in image processing part 105.

Scanner section 103 possesses: X spool device 107, X thread control device 109, device for generating high voltage 111, high-voltage switch gear unit 113, collimator 115, collimator control device 117, pedestal 121, pedestal control device 123, pedestal traverse measuring device 125, X thread detector 127, preamplifier 129, drive division 131, scan controller 133, central control unit 135 etc.

Scanner section 103 is shootings of carrying out subject 119, and gathers the device that photographed data (the X line sees through data, scan-data) back sends to image processing part 105.

X spool device 107 is the devices that produce the X line.X thread control device 109 is devices of sending to device for generating high voltage 111 based on the control signal of input information.Device for generating high voltage 111 is to produce high-tension device.High voltage switch part 113 is the devices that apply high voltage pulse to X spool device 107.

Collimator 115 is devices of adjusting the irradiation area of X line.Collimator 115 applies restriction along the direction of illumination of X line, makes subject 119 is carried out the required X line of projection to pass through.The action of collimator 115 is by 117 controls of collimator control device.

Pedestal 121 is the devices that support subject 119.Pedestal 121 is by lifting moving and vertically move, and makes subject 119 move to the diagnostic measures position of scanner section 103.The action of pedestal 121 is by 123 controls of pedestal control device.Pedestal traverse measuring device 125 is measured the rate of travel of pedestal 121.

X thread detector 127 is the devices that detect through the X line behind the subject 119.The X thread detector has a plurality of grooves (channel) as the detecting element of X line.Groove can constitute multiple row along the axon direction.Preamplifier 129 is the devices that are transformed to digital signal and send to image processing part 105 after the signal from X thread detector 127 is amplified.

Drive division 131 is the devices that drive X spool device 107, X thread detector 127, preamplifier 129 etc. with respect to subject 119 along the circumference direction.Scan controller 133 is the devices that carry out the action control etc. of drive division 131.

Central control unit 135 is the devices that carry out the action control of X thread control device 109, collimator control device 117, pedestal control device 123, pedestal traverse measuring device 125, scan controller 133 etc.

Fig. 9 is the pie graph of the image processing part 105 of x-ray ct device 100.

For image processing part 105, interconnect control part 137, storage device 139, display part 141, input and output portion 145 etc. by system bus 147.

Image processing part 510 is to see through data according to the X line of sending here from scanner section 103 to carry out Flame Image Process, and generates the device of view data.

Control part 137 has CPU (Central Processing Unit) (not shown), image processor (not shown), background projector (not shown), RAM (Random Access Memory) (not shown), ROM (Read Only Memory) (not shown) etc.

Control part 137 carries out various calculation process, the function of performance restructing operation device, image processing apparatus etc.137 pairs of data for projection of control part carry out image reconstruction process and generate the reconstructed image data, perhaps data for projection or reconstructed image are carried out the Flame Image Process of correcting process etc.

Storage device 139 is devices of storage data, has disk, floppy disk, memorizer, magnetic tape equipment, optical disc apparatus etc.Store program, the program carried out by control part 137 in the storage device 139 and carry out required data, OS (Operating System), Flame Image Process data etc.

Display part 141 is to have the CT image of subject 119 to carry out device shown to shooting, for example is display devices such as CRT monitor, liquid crystal panel.

Input and output portion 145 is the devices that carry out the input and the output of various data.Input/output unit 145 for example is the operating board (not shown) that possesses keyboard, indicating equipment etc., the input/output unit of various medium.

System bus 147 is to carry out the respectively path of giving and accepting of the control signal between device, data signal etc.

If input and output portion 145 input photography conditions (for example pedestal translational speed, tube current, tube voltage, layering (slice) position etc.), reconstruction parameter (for example being concerned about zone, reconstructed image size, contrary projected phase width, reconstruct filter function etc.) from image processing part 105, then x-ray ct device 100 is based on this indication, carry the required control signal of photography from central control unit 135 to X thread control device 109, pedestal control device 123, scan controller 133 etc., and reception photography commencing signal begins photography.

X-ray ct device 100 is then sent control signal by X thread control device 109 to device for generating high voltage 111 if begin photography, applies high voltage to X spool device 107, from X spool device 107 to subject 119 exposures.Simultaneously, x-ray ct device 100 is sent control signal from scan controller 133 to drive division 131, makes subject 119 rotations relatively such as X spool device 107, X thread detector 127, preamplifier 129.

On the other hand, x-ray ct device 100 is by pedestal control device 123, when scanning, circular orbit make mounting have the pedestal 121 of subject 119 static, and, when scanning, helical orbit makes pedestal 121 that mounting has a subject 119 moving around direction of principal axis is parallel along X spool device 107 grades.

The collimated instrument 115 restriction irradiation areas of the X line of irradiation absorb (decay) by each tissue in the subject 119, behind subject 119, are detected by X thread detector 127.Be transformed to electric current by X thread detector 127 detected X lines, amplify, be imported in the image processing part 105 as the data for projection signal by preamplifier 129.

137 pairs of data for projection signals of being imported of the control part of image processing part 105 are reconstructed computing, carry out image reconstruction process.The control part 137 of image processing part 105 is saved in reconstructed image in the storage device 139, as the CT pictorial display to display part 141.In addition, the control part 137 of image processing part 105 is shown to it on display part 141 after reconstructed image has been carried out processed.

Below, utilize Figure 10～Figure 13, x-ray ct device 1 grade of the 4th embodiment of the present invention is described.

With reference to Figure 10, the effective energy of the X line that x-ray ct device 100 is shone describes.

Figure 10 is the curve chart of the Energy distribution of expression X line.

Transverse axis is represented photon energy 149, and the longitudinal axis is represented energy density 151.Wherein, energy intensity 151 is equivalent to (photon energy) * (number of photons).

The Energy distribution of the X line that energy curve 153 expression is shone from X spool device 107 when establishing the X ray tube voltage for " 80kV ".

The Energy distribution of the X line that energy curve 155 expression is shone from X spool device 107 when establishing the X ray tube voltage for " 110kV ".

The Energy distribution of the X line that energy curve 157 expression is shone from X spool device 107 when establishing the X ray tube voltage for " 140kV ".

Shown in energy curve 153, energy curve 155, energy curve 157, change according to the X ray tube voltage from the photon energy and the photon numbers of X linear light of X spool device 107 irradiation.

In the X line shown in the energy curve 153, maximum photon energy and X ray tube voltage 80kV correspond to " 80keV ", but have considered that the X line effective energy after the Energy distribution for example is " 40keV ".

In the X line shown in the energy curve 155, maximum photon energy and X ray tube voltage 110kV correspond to " 110keV ", but have considered that the X line effective energy after the Energy distribution for example is " 45keV ".

In the X line shown in the energy curve 157, maximum photon energy and X ray tube voltage 140kV correspond to " 140keV ", but have considered that the X line effective energy after the Energy distribution for example is " 50keV ".

In addition, if the X ray tube voltage raises, then X line effective energy raises.In addition, as the method that X line effective energy is changed, except the method that makes the variation of X ray tube voltage, the method for the material of the target that also changes (will utilize Figure 33～Figure 37 to describe in the back).Below, " energy difference " conduct " effective energy difference " is described.

With reference to Figure 11～Figure 13, scanning describes to multipotency.

Multipotency scanning is by from the different a plurality of X lines of X spool device 107 irradiation effective energies, thereby (layering position) obtains the image capture method of the different a plurality of tomography pictures of X linear absorption coefficient in same cross section.

To be expression change the figure of the method for imaging that X line effective energy photographs by each scanning to Figure 11.

Figure 13 is the irradiation position among Figure 11 and Figure 12 and the graph of a relation of X line effective energy.

In addition, single pass is represented once to photograph around subject 119.That is, x-ray ct device 100 is obtained data for projection by single pass to each projection angle (position of finding a view) (0 °～360 °), this data for projection is implemented image reconstruction process obtain a tomography picture.

X-ray ct device 100 shines X line 165-1,165-2, the 165-3 of different effective energies respectively in scanning 161-1, scanning 161-2, scanning 161-3.That is, (1 week: the effective energy of the X line of irradiation is fixed 360 ° of rotations) at single pass.

For example, to establish X line effective energy among the 161-1 be 30keV to x-ray ct device 100 for the first time scanning, and 165-1 photographs from each irradiation position 163-1 (" zero ") beginning exposure; To establish X line effective energy among the 163-2 be 50keV for the second time scanning, and 165-2 photographs from each irradiation position 163-2 (" ") beginning exposure; To establish X line effective energy among the 161-3 be 70keV scanning for the third time, and 165-3 photographs from each irradiation position 163-3 (" △ ") beginning exposure.

X-ray ct device 100 generates image 167-1～image 167-3 at carrying out image reconstruction process respectively by each scanning data for projection that 161-1～scanning 161-3 obtains.

Because in each scanning 161-1～161-3, X line effective energy is different respectively, therefore, the tomography picture of same cross section even (layering position), for image 167-1～image 167-3 (distribution of X linear absorption coefficient), CT value contrast distribution (sensitivity) in other words is also different respectively.

Figure 12 is the figure that is illustrated in the method for imaging that change X line effective energy is photographed in the single pass.

X-ray ct device 100 comes the different a plurality of X lines of exposure effective energy according to projection angle (position of finding a view) in single pass 169.That is, (1 week: the effective energy of the X line of irradiation changes single pass 360 ° of rotations).

For example, it is 30keV and from irradiation position 163-1 (" zero ") exposure that x-ray ct device 100 is established X line effective energy, if X line effective energy is 50keV and from irradiation position 163-2 (" ") exposure, establish X line effective energy and be 70keV and from irradiation position 163-3 (" △ ") exposure.

100 pairs of data for projection of obtaining at each irradiation position 163-1 of x-ray ct device carry out image reconstruction process and generate image 167-1, the data for projection of obtaining at each irradiation position 163-2 is carried out image reconstruction process and generates image 167-2, the data for projection of obtaining at each irradiation position 163-3 is carried out image reconstruction process and generates image 167-3.

Because it is different respectively at each the irradiation position 163-1～irradiation position 163-3 X of place line effective energy, therefore, the tomography picture of same cross section even (layering position), for image 167-1～image 167-3 (distribution of X linear absorption coefficient), CT value contrast distribution (sensitivity) in other words is also different respectively.

Like this, in the 4th embodiment of the present invention, because the different a plurality of tomography pictures of contrast distribution (sensitivity) (image 167-1～image 167-3) are obtained in 100 pairs of same cross sections of x-ray ct device (layering position), therefore, the picture of reading by at a plurality of tomography pictures of same cross section (layering position) can look like to discern the information that can't discern from a tomography picture according to other tomographies.

In addition, in Figure 11, repeatedly photograph in 100 pairs of same cross sections of x-ray ct device (layering position).Therefore, the required time of photographing is elongated, but because quantity of information increases, thereby can reduce noise grade.

And in Figure 12, x-ray ct device 100 is obtained a plurality of tomography pictures in same cross section (layering position) by (rotate 1 time, around 1 week) photography once.Therefore, owing to the quantity of information in the tomography picture is limited, thus the noise grade increase, but can shorten the required time of photography.

In addition, in the above-described embodiment, the situation of the different a plurality of X lines of exposure effective energy is illustrated, but the different a plurality of X lines of irradiation power spectrum (at this moment, if in the time of the effective energy difference of each power spectrum), also can obtain the action effect same with above-mentioned embodiment.

More than have been described in detail,, can easily realize multipotency scanning from hardware, software two aspects by present embodiment.In addition, can realize improving visuognosis by colorize, the high-contrastization of the image of multipotency scanning photograph acquisition.

And then, can improve the high speed of multipotency scanning motion itself.

And, restructing operation, the Flame Image Process time of the view data that obtains by multipotency scanning etc. can be shortened, and noise can be reduced, improve the quality.

(the 5th embodiment)

The 5th embodiment is to distribute different monochromatic coloured silks to generate embodiment with these monochromatic color combined color images after synthetic by power spectrum or effective energy.Wherein, will be that example describes with the different situation of effective energy below, but the different situation of power spectrum too.

Utilize Figure 14～Figure 17, the 5th embodiment of the present invention is described.

With reference to Figure 14 and Figure 15, the color-ratio of a plurality of images of obtaining by multipotency scanning is described.

Figure 14 is the figure of expression color with respect to the ratio of image.

Figure 15 is the corresponding diagram of X line effective energy (X ray tube voltage) and ratio color frequency (ratio color).

100 couples of different a plurality of image 167-1～image 167-3 of contrast distribution (sensitivity) that obtain by multipotency scanning (with reference to Figure 11, Figure 12 etc.) of x-ray ct device, the pairing color of effective energy of the X line that distribution is shone in order to obtain this image, generate mono-color image 175-1～mono-color image 175-3, and these mono-color image are synthesized generate combined color image 177.

The color that 100 pairs of images of obtaining with low X line effective energy (low X ray tube voltage) of x-ray ct device distribute low frequency (long wavelength), the color of the image of obtaining with high X line effective energy (high X ray tube voltage) being distributed high frequency (short wavelength).For example, it is image branch that 80kV the obtains 174-1 (" red ") that mixes colours that 100 pairs of x-ray ct devices are established the X ray tube voltage, to establishing the X ray tube voltage is image branch that 110kV the obtains 174-2 (" green ") that mixes colours, and is image branch that 140kV the obtains 174-3 (" indigo plant ") (with reference to Figure 15) that mixes colours to establishing the X ray tube voltage.

It is that 80kV, 110kV, 140kV come the gray level (gray scale) in the image that exposure obtains that gray scale 171-1, gray scale 171-2, gray scale 171-3 represent to establish the X ray tube voltage respectively.Wherein, along with advancing to the direction of arrow 172, brightness increases, and promptly shows to brighten.

Monochromatic gray scale 173-1, monochromatic gray scale 173-2, monochromatic gray scale 173-3 represent respectively to divide mix colours 174-1 (" red " " // "), color 174-2 (" green " “ "), color 174-3 (" indigo plant " " ≡ ≡ ") and the monochromatic gray level that generates to gray scale 171-1, gray scale 171-2, gray scale 171-3.Wherein, along with advancing to the direction of arrow 176, brightness increases.

X-ray ct device 100 is the image 167-1 that 80kV comes exposure to obtain at establishing the X ray tube voltage, divides the 174-1 (" red ") that mixes colours based on gray scale 171-1 and monochromatic gray scale 173-1, generates mono-color image 175-1 thus.X-ray ct device 100 is the image 167-2 that 110kV comes exposure to obtain at establishing the X ray tube voltage, divides the 174-2 (" green ") that mixes colours based on gray scale 171-2 and monochromatic gray scale 173-2, generates mono-color image 175-2 thus.X-ray ct device 100 is the image 167-3 that 140kV comes exposure to obtain at establishing the X ray tube voltage, divides the 174-3 (" green ") that mixes colours based on gray scale 171-3 and monochromatic gray scale 173-3, generates mono-color image 175-3 thus.

100 couples of mono-color image 175-1～mono-color image 175-3 of x-ray ct device synthesize and generate combined color image 177.

Like this, 100 couples of image 167-1 of x-ray ct device～image 167-3 distributes and the corresponding color of X line effective energy.X-ray ct device 100 is for example same with visible light, distribute red to the image that obtains with minimum X line effective energy, the image that obtains with next to the lowest X line effective energy is distributed green, to the image assigned colors blue that obtains with the highest X line effective energy, and with these image overlay.

X-ray ct device 100 can make poor (poor sensitivity) image conversion of the contrast distribution corresponding with each X line effective energy by generating combined color image 177.

In addition, illustrated, but except reconstructed image (reconstructed image data) at processing as the image 167 of reconstructed image, also can be, these data have been implemented data after the predetermined processing etc. carry out same processing for projection image's (data for projection).

Therefore, image 167 not only refers to reconstructed image, also comprises the data for projection that obtained by photography, reconstructed image has been implemented the image after the predetermined processing etc.

With reference to Figure 16 and Figure 17, the action of the image processing part 105 of x-ray ct device 100 is described.

Figure 16 is the figure of handling process in the image processing part 105 of expression x-ray ct device 100.

Figure 17 is the flow chart of action of the image processing part 105 of expression x-ray ct device 100.

100 pairs of subjects of x-ray ct device 119 carry out multipotency scanning (step S1001).The image processing part 105 of x-ray ct device 100 is obtained image 167-1, image 167-2, image 167-3 (step S1002) respectively by the X line of irradiation by the Energy distribution of spectrum curve 153, energy curve 155, energy curve 157 expressions.

Image processing part 105 couples of image 167-1 based on the X line of minimum effective energy divide the 174-1 (" red ") that mixes colours, and generates mono-color image 175-1.Equally, image processing part 105 couples of image 167-2 based on the X line of the second low effective energy divide the 174-2 (" green ") that mixes colours, and generates mono-color image 1175-2.Equally, 105 pairs of image processing parts divide the 174-3 (" indigo plant ") that mixes colours based on the image 167-3 of the X line of high effective energy, generate mono-color image 175-3 (step S1003).

105 couples of mono-color image 175-1～mono-color image 175-3 of image processing part synthesize, and generate combined color image 177 (step S1004).

Through above process, 105 couples of image 167-1～image 167-3 of the image processing part of x-ray ct device 100 distribute different colors respectively, generate mono-color image 175-1～mono-color image 175-3, and generate combined color image 177 by these mono-color image are synthesized.

Like this, in the 5th embodiment, the image processing part 105 of x-ray ct device 100 distributes different colours respectively and synthesizes to the different a plurality of images of contrast distribution, generate a combined color image, can generate the quantity of information more images thus, differential and separating capacity, contrast in tissue and the visuognosis of diagnosis object tissue can be improved, and then diagnostic accuracy can be improved.

In addition, illustrated, but except reconstructed image (reconstructed image data), for projection image's (data for projection), these data have been implemented data after the predetermined processing etc. also can carry out same processing at processing as the image 167 of reconstructed image.

Therefore, image 167, mono-color image 75, combined color image 177 not only refer to reconstructed image, also comprise the data for projection that is obtained by photography.That is, carry out the qualification especially on opportunity of image reconstruction process.X-ray ct device 100 also can carry out image reconstruction process to data for projection after any processing of having carried out step S1002～step S1004.

According to present embodiment, after distributing the color corresponding, show as coloured image with X line effective energy, can improve the visuognosis of the image that obtains by multipotency scanning.

(the 6th embodiment)

The 6th embodiment is the embodiment that generates the difference combined color image.Wherein, be that example is illustrated with the different situation of effective energy below, but under the different situation of power spectrum too.

With reference to Figure 18 and Figure 19, the 6th embodiment of the present invention is described.Figure 18 is the figure of handling process in the image processing part 105 of expression x-ray ct device 100.

Figure 19 is the flow chart of action of the image processing part 105 of expression x-ray ct device 100.

100 pairs of subjects of x-ray ct device 119 carry out multipotency scanning (step S2001).The image processing part 105 of x-ray ct device 100 is obtained image 167-1, image 167-2, image 167-3 (step S2002) respectively by the X line of irradiation by the Energy distribution of spectrum curve 153, energy curve 155, energy curve 157 expressions.

Image processing part 105 becomes the processing image 183 (step S2003) of the benchmark of painted usefulness based on image 167-1, image 167-2, image 167-3.Wherein, the Filtering Processing image that to handle image 183 for example be the average image, utilize median filter etc. to generate.

Image processing part 105 is calculated image 167-1, image 167-2, image 167-3 and is handled the difference of image 183, generates difference image 185-1, difference image 185-2, difference image 185-3 (step S2004).In addition, image processing part 105 also can multiply by the coefficient of regulation to difference value, generates difference image 185-1～difference image 185-3.

Image processing part 105 couples of image 167-1 based on the X line of minimum effective energy divide the 174-1 (" red ") that mixes colours, and generates difference mono-color image 187-1.Equally, image processing part 105 couples of image 167-2 based on the X line of the second low effective energy divide the 174-2 (" green ") that mixes colours, and generates difference mono-color image 187-2.Equally, 105 pairs of image processing parts divide the 174-3 (" indigo plant ") that mixes colours based on the image 167-3 of the X line of high effective energy, generate difference mono-color image 187-3 (step S2005).

105 couples of difference mono-color image 187-1 of image processing part～difference mono-color image 187-3 synthesizes, and generates difference combined color image 189 (step S2006).

Through above process, the image processing part 105 of x-ray ct device 100 generates based on image 167-1～image 167-3 and handles image 183, and generation is handled the difference image 185-1～difference image 185-3 of image 183 at this, distribute different colours to generate difference mono-color image 187-1～difference mono-color image 187-3 then respectively, by synthetic these difference mono-color image, generate difference combined color image 189.

Like this, in the 6th embodiment, because the image processing part 105 of x-ray ct device 100 distributes different colours respectively and synthesizes to the different a plurality of difference images of contrast distribution, generate a combined color image, can generate the quantity of information more images thus, differential and separating capacity, contrast in tissue and the visuognosis of diagnosis object tissue can be improved, and then diagnostic accuracy can be improved.

And, in the 6th embodiment,, therefore, come expanded scope by the coefficient that difference value be multiply by regulation, thereby can emphasize difference because 105 pairs of difference images of image processing part of x-ray ct device 100 are handled.And, because image processing part 105 can be transformed to integer with it by difference value is adjusted, thereby be not by floating-point operation but handle difference value by integer arithmetic, therefore, can alleviate the burden relevant with calculation process.

In addition, illustrated, but except reconstructed image (reconstructed image data), for projection image's (data for projection), these data have been implemented data after the predetermined processing etc. also can carry out same processing at processing as the image 167 of reconstructed image.

Therefore, image 167, processing image 183, difference image 185, difference mono-color image 187, difference combined color image 189 not only refer to reconstructed image, also comprise the data for projection that is obtained by photography.That is, carry out the qualification especially on opportunity of image reconstruction process.X-ray ct device 100 also can carry out image reconstruction process to data for projection after any processing of having carried out step S2001～step S2006.

According to present embodiment, for each X line effective energy with difference image the average image, show as coloured image after distributing the color corresponding, thereby can improve the visuognosis of the image that obtains by multipotency scanning with X line effective energy.

(the 7th embodiment)

The 7th embodiment is that the image that generates the processing image that obtained by the different a plurality of images of X line effective energy, constitute with the pixel of the difference maximum of each image is as the embodiment of emphasizing image.Wherein, be that example is illustrated with the different situation of effective energy below, but under the different situation of power spectrum too.

With reference to Figure 20 and Figure 21, the image processing method in the 4th embodiment of the present invention (emphasize that image generate handle) etc. is described.

Figure 20 is the figure of handling process in the image processing part 105 of expression x-ray ct device 100.

Figure 21 is the flow chart of action of the image processing part 105 of expression x-ray ct device 100.

100 pairs of subjects of x-ray ct device 119 carry out multipotency scanning (step S3001).The image processing part 105 of x-ray ct device 100 is obtained image 167-1, image 167-2, image 167-3 (step S3002) respectively by the X line of irradiation by the Energy distribution of spectrum curve 153, energy curve 155, energy curve 157 expressions.

Image processing part 105 becomes the processing image 183 (step S3003) of the benchmark of painted usefulness based on image 167-1, image 167-2, image 167-3.Wherein, the Filtering Processing image that to handle image 183 for example be the average image, utilize median filter etc. to generate.

Image processing part 105 is calculated image 167-1, image 167-2, image 167-3 and is handled the difference of image 183, generates difference image 185-1, difference image 185-2, difference image 185-3 (step S3004).In addition, image processing part 105 also can multiply by the coefficient of regulation to difference value, generates difference image 185-1～difference image 185-3.

Image processing part 105 extracts and handles the pixel of the difference maximum of image 183 by each coordinate from each difference image 185-1～difference image 185-3, generate and emphasize image 191 (step S3005).

For example, coordinate (x in difference image 185-1, difference image 185-2, difference image 185-3, when pixel value y) is respectively k * Δ a, k * Δ b, k * Δ c, emphasize in the image 191 coordinate (x, pixel value y) be MAX (| k * Δ a|, | k * Δ b|, | k * Δ c|).

Wherein, Δ a, Δ b, Δ c respectively denotation coordination (x, the image 167-1 that y) locates, image 167-2, image 167-3 and handle the pixel difference value of image 183, k represent the predetermined coefficients that multiplies each other with this pixel difference value.In addition, MAX (p, q, the r) maximum of expression p, q, r, | s| represents the absolute value of s.

Through above process, the image processing part 105 of x-ray ct device 100 generates based on image 167-1～image 167-3 and handles image 183, and generating the difference image 185-1～difference image 185-3 that handles image 183 at this, the pixel difference value that extracts the absolute value maximum by each coordinate generates and emphasizes image 191 then.

Like this, in the 7th embodiment,, generate one and emphasize image, therefore can improve the contrast of image because the image processing part 105 of x-ray ct device 100 extracts the pixel difference value of absolute value maximum from the different a plurality of difference images of contrast distribution.

In addition, illustrated, but except reconstructed image (reconstructed image data), for projection image's (data for projection), these data have been implemented data after the predetermined processing etc. also can carry out same processing at processing as the image 167 of reconstructed image.

Therefore, image 167, handle image 183, difference image 185, emphasize that image 191 not only refers to reconstructed image, also comprise the data for projection that obtains by photography.That is, carry out the qualification especially on opportunity of image reconstruction process.X-ray ct device 100 also can carry out image reconstruction process to data for projection after any processing of having carried out step S3001～step S3005.

According to present embodiment, (for example carry out processing image that Flame Image Process obtains by generating when the multipotency scan different a plurality of images of energy of acquisition, the Filtering Processing image of the average image or median filter etc.), and generate the image that constitutes with the pixel of the difference maximum of handling image by in each image, thereby can gather the image of high-contrast.

(the 8th embodiment)

The 8th embodiment is to be used to the more high speed calculation process that gathers of calculation process that image processing part 105 is carried out, is the embodiment that a plurality of data for projection of will repeatedly photograph with different effective energies and obtain and camera positions are reconstructed as 1 data explicitly.Wherein, be that example is illustrated with the different situation of effective energy below, but under the different situation of power spectrum too.

With reference to Figure 22 and Figure 23, the 8th embodiment of the present invention is described.105 pairs of various data of the image processing part of x-ray ct device 100 are carried out various computings.

Data representation image processing part 105 handled various data for example are data for projection, reconstructed image data, calibration (calibration) data etc.The 105 handled various computings of " computing " presentation video handling part, for example image reconstruction computing etc.

In Figure 22 and Figure 23,, be that example describes with image reconstruction computing to data for projection as a mode at " computing " of " data ".

Figure 22 is that the existing data operation of expression is handled the figure of (indivedual calculation process).

X-ray ct device 100 carries out multipotency scanning, obtains the data for projection 193-1～data for projection 193-4 based on different a plurality of X line effective energies.

Wherein, a data for projection 193-1～data for projection 193-4 is assigned with a projection data values respectively.

105 couples of data for projection 193-1～data for projection 193-4 of the image processing part of x-ray ct device 100 independently carry out image reconstruction computing 195-1～image reconstruction computing 195-4 respectively, generate reconstructed image data 97-1～reconstructed image data 97-4.Image processing part 105 carries out image reconstruction computing 195-1～image reconstruction computing 195-4 of four times for four data for projection 193-1～data for projection 193-4 that obtain at same tomographic image.

Figure 23 is that expression data operation of the present invention is handled the figure of (gathering calculation process).

X-ray ct device 100 carries out multipotency scanning, obtains the data for projection 193-1～data for projection 193-4 that obtains based on the different a plurality of X lines of X line effective energy.

Wherein, a data for projection 193-1～data for projection 193-4 is assigned with a projection data values respectively.

The image processing part 105 of x-ray ct device 100 in conjunction with (with reference to Figure 22), generates 64 data for projection 199 (with reference to Figure 23) with 16 data for projection 193-1～data for projection 193-4.

105 couples of data for projection 193-1 of image processing part～data for projection 193-4 in conjunction with after data for projection 199 gather and carry out image reconstruction computing 195, generate reconstructed image data 101.Image processing part 105 is obtained each reconstructed image data 97-1～reconstructed image data 97-4 by cutting apart reconstructed image data 101.

Image processing part 105 carries out an image reconstruction computing 195 for four data for projection 193-1～data for projection 193-4 that obtain at same tomographic image.

Through above process, 105 pairs of a plurality of data that obtain by multipotency scanning of image processing part are carried out combination, and data are distributed a plurality of data values, and next gathering at this binding data carried out calculation process.That is, Flame Image Process is carried out as 1 data explicitly in a plurality of data for projection and the camera positions that obtain repeatedly photographing with different effective energies, has reduced tediously long computing thus.

Like this, in the 8th embodiment, when 105 pairs of a plurality of data based on different X line effective energies of image processing part are carried out same calculation process, can reduce operation times, thereby can shorten restructing operation time and Flame Image Process time.

According to present embodiment, by a plurality of data for projection and the camera positions that obtain of repeatedly photographing with different effective energies are reconstructed as 1 data explicitly, particularly, make a data value (data for projection, reconstructed image data) have a plurality of data values, thereby can shorten the restructing operation time and the Flame Image Process time of multipotency scan-data.

(the 9th embodiment)

Utilize Figure 24 and Figure 25, the 9th embodiment of the present invention is described.In the 9th embodiment, the pairing a plurality of data for projection of different power spectrum (or effective energy) are carried out interpolation, generate power spectrum (or effective energy) the pairing data for projection different with these power spectrums, obtain reconstructed image.Wherein, be that example is illustrated with the different situation of effective energy below, but under the different situation of power spectrum too.

Figure 24 is the curve chart of the relation of expression photon energy and X linear absorption coefficient.In Figure 24, transverse axis is represented photon energy 1103[keV], the longitudinal axis is represented X linear absorption coefficient 1105[cm ²/ g].

The X line effective energy that the inherent X linear absorption coefficient of each material correspondence sees through and have higher non-linearity.The X linear absorption coefficient is represented by the nonlinear function of photon energy.Therefore, if based on this function, between two data, carry out two point interpolations (linear interpolation) and newly-generated data then can produce big error.

If x-ray ct device 100 is obtained in the mensuration of reality by the data of point 1109 expressions and by the data of putting 1111 expressions, then the image processing part 105 of x-ray ct device 100 is based on point 1109 and put 1111 and carry out linear interpolation, newly-generated data by point 1113 expressions.

Non-linear big part in curve 1107, the error 1115 in the X linear absorption coefficient 1105 also increase on respective degrees ground.

Figure 25 is the curve chart of the relation of expression photon energy and X linear absorption coefficient.

In Figure 25, transverse axis is represented photon energy 1103[keV] logarithm value 1117 (log[keV]), the longitudinal axis is represented X linear absorption coefficient 1105[cm ²/ g] logarithm value 1119 (log[cm ²/ g]).

Curve chart shown in Figure 25 is the curve chart after the diaxon to curve chart shown in Figure 24 carries out logarithmic transformation.The curve 1107 of Figure 24 is transformed to the curve 1121 of Figure 25.Curve 1121 compares with curve 1107, and is non-linear very low, the linear raising.

If x-ray ct device 100 is obtained the represented data of point 1109 among Figure 24 and is put 1111 represented data in the mensuration of reality, then the image processing part 105 of x-ray ct device 100 carries out logarithmic transformation to it respectively, is transformed to the point 1121 among Figure 25 and puts 1123 represented data.

In addition, 105 pairs of photon energies 1103 of image processing part and X linear absorption coefficient 1105 carry out logarithmic transformation, are transformed into photon energy logarithm value 1117 and X linear absorption coefficient logarithm value 1119.

Image processing part 105 is based on point 1121 and put 1123 and carry out linear interpolation, newly-generated data by point 1125 expressions.

The curve 1121 of Figure 25 compares with the curve of Figure 24 1107, owing to linearity improves, so the error 1127 in the X linear absorption coefficient logarithm value 1119 also reduces to respective degrees.Therefore, x-ray ct device 100 can be obtained and the actual very approaching value of X linear absorption coefficient.

Like this, in the 9th embodiment, the image processing part 105 of x-ray ct device 100 can be calculated the data such as X linear absorption coefficient of undeterminate X line effective energy accurately by at diaxon interpolation being carried out in the number space.

And the image processing part 105 of x-ray ct device 100 utilizes data such as limited X linear absorption coefficient, can generate the data in the multipotency scanning, thus the data volume that can reduce exposure, photography time, be kept.

According to present embodiment, by in x-ray ct device, the a plurality of data for projection that obtain repeatedly photographing with different X heat inputs are carrying out interpolation to the number space, infer desirable energy attenuation coefficient value (projection data values), thereby can generate the data of different X heat inputs accurately, thus, can reduce light exposure when obtaining the photogram of energy more than three kinds by multipotency scanning, reduce required calibration data quantity, shorten the photography time of calibration data.

(the 10th embodiment)

The 10th embodiment is the embodiment that is used to make the Flame Image Process of noise smoothingization.Wherein, be that example describes with the different situation of effective energy below, but under the different situation of power spectrum too.

Utilize Figure 26, the 10th embodiment of the present invention is described.

Figure 26 is the figure of the establishing method of expression Filtering Processing parameter.

The image processing part 105 of x-ray ct device 100 changes the nuclear size (kernel size) of filtering according to the size of X line effective energy when the data for projection obtained by multipotency scanning or reconstructed image data are carried out Filtering Processing.

For example, 105 pairs of X ray tube voltage of image processing part are the data for projection that 80kV obtains, and carry out the smoothing Filtering Processing with the nuclear size filtering device 1129 with 7 * 7 wave filter on the groove direction and the locality of finding a view; To the X ray tube voltage is the data for projection that 110kV obtains, and carries out the smoothing Filtering Processing with the nuclear size filtering device 1131 with 5 * 5 wave filter on the groove direction and the locality of finding a view; To the X ray tube voltage is the data for projection that 140kV obtains, and carries out the smoothing Filtering Processing with the nuclear size filtering device 1133 with 3 * 3 wave filter on the groove direction and the locality of finding a view.Image processing part 105 carries out the addition average treatment near 9 pixels that comprise subject pixels in smoothing is handled.

Along with X line effective energy increases, obtainable quantity of information increases, and the noise of obtaining in the data reduces.And along with the nuclear size increase of wave filter, smoothing effect and noise reduction increase.

Therefore, image processing part 105 carries out Flame Image Process according to the nuclear size of X line effective energy change wave filter.The nuclear size that data for projection that 105 pairs of image processing parts are obtained with high X line effective energy or reconstructed image reduce wave filter is carried out Filtering Processing, and the nuclear size that the data for projection obtained with low X line effective energy or reconstructed image increase wave filter is carried out Filtering Processing.

Thereby the SN in each image (data for projection or reconstructed image) reduces than the difference of the numerical value of (Contrast to Noise Ratio) than (Signal to Noise Ratio) and CN.

In addition, wish to change the nuclear size of wave filter, make that SN ratio or the CN in each image (data for projection or reconstructed image) is more equal than as far as possible according to X line effective energy.

But if only adjust the nuclear size of wave filter, then SN ratio or CN are than becoming equal value.Therefore, wish the various image processing filters of applied in any combination.

About image processing filter, be not limited to the smoothing wave filter, also can use median filter, weighting summation wave filter, similar degree wave filter, combination that these self adaptation of filter wave filter etc. are arranged.And, to being illustrated in the groove direction of data for projection and the two dimensional filter on the locality of finding a view, but also can comprise column direction and use any one two dimensional filter, also can use the three-dimensional filter of groove direction, the locality of finding a view, column direction.

In addition, the process object of above-mentioned image processing filter is not limited to data for projection, also can be reconstructed image.Under this situation, can carry out Filtering Processing with any dimension that comprises x direction, y direction, z direction.

Like this, in the 7th embodiment, because 105 pairs of images of obtaining by the X line of low effective energy (data for projection or reconstructed image) of the image processing part of x-ray ct device 100 are used the big wave filter of noise reduction, the image of obtaining by the X line of high effective energy (data for projection or reconstructed image) is used the little wave filter of noise reduction, therefore, the difference of the numerical value of SN ratio in each image (data for projection or reconstructed image) that can reduce to obtain and CN ratio by multipotency scanning.

In addition, in the 10th embodiment,, therefore, need not to change the device formation and the action control of scanner section 103 sides owing to make SN ratio and CN than levelized by the software processes in the image processing part 105.

(the 11st embodiment)

The 11st embodiment is the embodiment that changes scanning speed according to the effective energy of X line.Wherein, be that example describes with the different situation of effective energy below, but under the different situation of power spectrum too.

Utilize Figure 27 and Figure 28, the x-ray ct device 100 of the 11st embodiment of the present invention is described.

Figure 27 is the figure of the control of the expression scanning speed corresponding with X line effective energy.

Figure 28 is the irradiation position among Figure 27 and the graph of a relation of X line effective energy and scanning speed.

The scanner section 103 of x-ray ct device 100 changes the speed 1135 of scanning 161 according to X line effective energy from 107 pairs of subject 119 exposures of X spool device the time.That is, scanner section 103 changes X spool device 107 and X thread detector 127 etc. around in 119 1 weeks of the subject required times according to the effective energy of the X line that shines from X spool device 107.

For example, scanner section 103 is 80kV when photographing (scanning 161-1) in the X ray tube voltage, make scanning speed 1135-1 be 1.0 seconds/transfer exposure 165-1 photograph (scanning in 1.0 seconds); In the X ray tube voltage is 110kV when photographing (scanning 161-2), make scanning speed 1135-2 be 0.5 second/transfer exposure 165-2 photograph (scanning in 0.5 second); In the X ray tube voltage is 140kV when photographing (scanning 161-3), make scanning speed 1135-3 be 0.33 second/transfer exposure 165-3 photograph (scanning in 0.33 second).

If other conditions among scanning 161-1～scanning 161-3 are identical, then along with scanning speed 1135 reduces, changeing the quantity of information that was obtained in 1 week increases, and the noise of obtaining in the data reduces.

Therefore, scanner section 103 changes scanning speed according to X line effective energy, carries out roentgen radiation x from X spool device 107.X-ray ct device 100 reduces scanning speed when the low X line of irradiation effective energy photographs, and increases scanning speed and photograph when the high X line of irradiation effective energy.

Therefore, the difference of the numerical value of ratio of the SN in each image (data for projection or reconstructed image) and CN ratio reduces.

In addition, wish to change scanning speed, make that SN ratio or the CN in each image (data for projection or reconstructed image) is more equal than as far as possible according to X line effective energy.

Like this, in the 11st embodiment, because reducing scanning speed when the low X line of irradiation effective energy, the scanner section 103 of x-ray ct device 100 photographs, increasing scanning speed when the high X line of irradiation effective energy photographs, therefore, the difference of the numerical value of SN ratio in each image (data for projection or reconstructed image) that can reduce to obtain and CN ratio by multipotency scanning.

In addition, in the 8th embodiment,, therefore, need not to change the software in the image processing part 105 owing to make SN ratio and CN than normalization by the action control of scanner section 103 sides.

(the 12nd embodiment)

The 12nd embodiment is the embodiment that changes tube current according to X line effective energy.Wherein, be that example describes with the different situation of effective energy below, but under the different situation of power spectrum too.

Utilize Figure 29 and Figure 30, the x-ray ct device 100 of the 12nd embodiment of the present invention is described.

Figure 29 is the figure of the control of the expression x-ray tube current corresponding with X line effective energy.

Figure 30 is the irradiation position among Figure 29 and the graph of a relation of X line effective energy and x-ray tube current.

The scanner section 103 of x-ray ct device 100 changes x-ray tube current in the X spool device 107 according to X line effective energy from 107 pairs of subject 119 exposures of X spool device the time.

Scanner section 103 in the scanning 169 of subject during 119 1 weeks, shines the X line 165 of different effective energies at X spool device 107 and X thread detector 127 etc. by each position 163 of scanning 169.

For example, scanner section 103 is that to make x-ray tube current be that 300mA comes exposure 165-1 the 163-1 place, position of 80kV in the X ray tube voltage, photographs; In the X ray tube voltage is that to make tube current be that 159mA comes exposure 165-2 the 163-2 place, position of 110kV, photographs; In the X ray tube voltage is that to make x-ray tube current be that 99mA comes exposure 165-3 the 163-3 place, position of 140kV, photographs.

If other conditions in the scanning 169 are identical, then along with x-ray tube current increases, changeing the quantity of information that was obtained in 1 week increases, and the noise of obtaining in the data reduces.

Therefore, scanner section 103 changes x-ray tube current according to X line effective energy, carries out roentgen radiation x from X spool device 107.Scanner section 103 increases x-ray tube current when the low X line of irradiation effective energy photographs, and reduces x-ray tube current and photograph when the high X line of irradiation effective energy.

Thereby the difference of the SN ratio in each image (data for projection or reconstructed image) and the numerical value of CN ratio reduces.

In addition, wish to change x-ray tube current, make that SN ratio or the CN in each image (data for projection or reconstructed image) is more equal than as far as possible according to X line effective energy.

And, when in 1 week of commentaries on classics, changing X line effective energy, wish according to this X line effective energy real time altering x-ray tube current.

Like this, in the 12nd embodiment, because increasing x-ray tube current when the low X line of irradiation effective energy, the scanner section 103 of x-ray ct device 100 photographs, reducing x-ray tube current when the high X line of irradiation effective energy photographs, therefore, the difference of the numerical value of SN ratio in each image (data for projection or reconstructed image) that can reduce to obtain and CN ratio by multipotency scanning.

And, in the 12nd embodiment,, therefore, need not to change the software in the image processing part 105 owing to make SN ratio and CN than normalization by the action control of scanner section 103 sides.

In addition, in the 11st embodiment, the multipotency scanning in 1 scanning need be changed scanning speed in 1 scanning, be difficult to control.On the other hand, in the 12nd embodiment, can change x-ray tube current at a high speed, thus the multipotency scanning in 1 scanning of correspondence easily.

(the 13rd embodiment)

The 13rd embodiment is the embodiment that changes the quantity (being equivalent to the range of exposures ratio) of camera positions according to X line effective energy.Wherein, be that example is illustrated with the different situation of effective energy below, but under the different situation of power spectrum too.

Utilize Figure 31 and Figure 32, the x-ray ct device 100 of the 13rd embodiment of the present invention is described.

Figure 31 is the figure that the proportion control of the find a view positional number corresponding with X line effective energy is represented.

Figure 32 is the irradiation position among Figure 31 and the graph of a relation of the X line effective energy and the positional number of finding a view.

The scanner section 103 of x-ray ct device 100 changes the ratio of the quantity (positional number of finding a view) of camera positions according to X line effective energy from 107 pairs of subject 119 exposures of X spool device the time.

Scanner section 103 in the scanning 169 of subject during 119 1 weeks, changes the quantitative proportion of the position 163 of exposure 165 by each X line effective energy at X spool device 107 and X thread detector 127 etc.

For example, for scanner section 103, if the ratio that the position 163-1 that photographs during X ray tube voltage 80kV changeed in 1 week is 54%, if the ratio that the position 163-2 that photographs during X ray tube voltage 110kV changeed in 1 week is 28%, the ratio that the position 163-3 that photographs when establishing X ray tube voltage 140kV changeed in 1 week is 18%.

If other conditions in the scanning 169 are identical, the quantity of information that big more 1 week of commentaries on classics of the ratio of the quantity of the position 163 of then photographing (positional number of finding a view) obtains increases more, and the noise of obtaining in the data reduces.

Therefore, scanner section 103 changes the ratio of the quantity (positional number of finding a view) of the position 163 of photographing according to X line effective energy, carries out roentgen radiation x from X spool device 107.Scanner section 103 increases the ratio of the quantity (positional number of finding a view) of irradiation position when the X line of the low effective energy of irradiation photographs, and the ratio that reduces the quantity (positional number of finding a view) of irradiation position when the X line of the high effective energy of irradiation is photographed.

Thereby the difference of the SN ratio in each image (data for projection or reconstructed image) and the numerical value of CN ratio reduces.

In addition, wish to change the ratio of the quantity (positional number of finding a view) of the position of photographing, make that SN ratio or the CN in each image (data for projection or reconstructed image) is more equal than as far as possible according to X line effective energy.

Like this, in the 13rd embodiment, because the scanner section 103 of x-ray ct device 100, quantity (positional number of finding a view) the ratio increase of shining the position of the X line that hangs down effective energy is photographed, quantity (positional number of the finding a view) ratio of position of the X line of the high effective energy of irradiation is reduced to photograph, therefore, the difference of the numerical value of SN ratio in each image (data for projection or reconstructed image) that can reduce to obtain and CN ratio by multipotency scanning.

In addition, different with the 11st and the 12nd embodiment in the 13rd embodiment, need not to change x-ray tube current and scanning speed.

According to present embodiment, by according to the X heat input that in x-ray ct device, shines, change the ratio of changeing 1 positional number of finding a view in the rotation, can make in each energy noisiness about equally.

(the 14th embodiment)

The 14th embodiment is the target that comprises the impingement area that possesses different collision angles, makes the impingement area of electron beam hits change the embodiment of the effective energy of X line by change.Wherein, below with the change effective energy situation be that example describes, but the change power spectrum situation under too.

Utilize Figure 33～Figure 35, the x-ray ct device 100 of the 14th embodiment of the present invention is described.

Figure 33 is the figure of expression X spool device 107.

X spool device 107 possesses: target (anode) 1137, deflector 1141 and electron gun (negative electrode) 1139.X spool device 107 sends electron beam 1143 from electron gun 1139, adjusts the angle of electron beams 1143 by deflector 1141, makes itself and the impingement area collision of target 1137, thus generation X line 1145.

Figure 34 is the approximate three-dimensional map of target 1137.

Figure 35 is the figure of a form (target 1137a) of expression target 1137.Figure 35 is equivalent to the A direction of arrow of Figure 34 to view.

Target 1137a possesses a plurality of impingement area 1138-1～impingement area 1138-4.Each impingement area 1138-1～impingement area 1138-4 becomes different angles (θ 1～θ 4) with respect to the direction of advance of electron beam 1143 respectively.

The effective energy of X line 1145 changes according to collision angle (direction of advance of electron beam 1143 is with respect to the angle of impingement area 1138).Along with collision angle increases, the effective energy of the X line 1145 that is produced increases, and along with collision angle reduces, the effective energy of the X line 1145 that is produced reduces.

That is, X spool device 107 makes electron beam 1143 collide impingement area 1138-1～impingement area 1138-4 of target 1137a, produces the X line 1145 of different effective energies respectively from each impingement area 1138-1～impingement area 1138-4.

In addition, optionally collide the impingement area 1138 of desirable collision angle, make the direction of advance deflection of electron beam 1143 by deflector 1141 in order to make electron beam 1143.At this moment, for example can utilize and fly focus (flying focal spot) mechanism.

Like this, in the 14th embodiment, because in the X of x-ray ct device 100 spool device 107, comprise the target of impingement area, therefore, can produce the X line of different effective energies to each impingement area by making electron beam hits with different a plurality of collision angles.In addition, can carry out the change of X line effective energy at a high speed.

Therefore, the X spool device 107 of x-ray ct device 100 can shine the different a plurality of X lines of effective energy in multipotency scanning.

In addition, X spool device 107 can change X line effective energy by changing at a high speed the position (by the position of finding a view) that X line effective energy photographs, and can carry out multipotency scanning in single pass.

And, can constitute target by single material, therefore, raise the target raw material easily.

In addition, limit especially, can 2 kinds, impingement area more than 3 kinds or 4 kinds be set on the target about the quantity of the impingement area of target and the size of collision angle.

According to present embodiment, in the X spool with different a plurality of targets angles, for example utilization flies focusing mechanism and makes the position of arriving different collision angles or different target matter from the electron irradiation of negative electrode, thereby can carry out the irradiation of different X heat inputs at a high speed.

(the 15th embodiment)

The 15th embodiment is to utilize multiple unlike material to constitute target, makes the position of electron beam hits change the embodiment of X line effective energy by change.Wherein, below with the change effective energy situation be that example is illustrated, but the change power spectrum situation under too.

Utilize Figure 36 and Figure 37, the x-ray ct device 100 of the 15th embodiment is described.

Figure 36 is the figure of a form (target 1137b) of expression target 1137.Figure 36 is equivalent to the A direction of Figure 34 to view.

Target 1137b is made of a plurality of target structure 1147-1～target structure 1147-4.Target structure 1147-1～target structure 1147-4 is the material difference separately.

Figure 37 is the curve chart of the Energy distribution of the X line of expression when having utilized the different target of material.

Transverse axis is represented photon energy 149, and the longitudinal axis is represented energy density 151.In addition, energy intensity 151 is equivalent to (photon energy) * (number of photons).

The Energy distribution of the X line 1145 when energy curve 149 and energy intensity 151 represent that respectively target 1137 adopted different material A and material B.

Target 1137 having been adopted under the situation of material A,, produce characteristic X line in the position of point 1153 with reference to energy curve 1149.Target 1137 having been adopted under the situation of material B,, produce characteristic X line in the position of point 1155 with reference to energy curve 1151.

Like this, when producing characteristic X line, the effective energy of X line is represented the distinctive value of target matter when the energy intensity of specific photon energy is outstanding.

For example, when target matter is molybdenum, can produce characteristic X line, when target matter can be with the photon energy generation characteristic X line of about 70keV during for tungsten with the photon energy of about 20keV.Compare with the situation that does not produce characteristic X line, the value deflection of X line effective energy produces characteristic X line one side.

Therefore, the effective energy of X line 1145 changes according to the material of target 1137.

That is, the X spool device 107 of x-ray ct device 100 makes electron beam 1143 collide target structure 1147-1～target structure 1147-4 of target 1137b, produces the X line of different effective energies respectively from each target structure 1147-1～target structure 1147-4.

In addition, optionally collide desirable target structure 1147, make the direction of advance deflection of electron beam 1143 by deflector 1141 in order to make electron beam 1143.At this moment, for example can utilize and fly focusing mechanism.

Like this, in the 15th embodiment, because in the X of x-ray ct device 100 spool device 107, possess respectively the target that a plurality of target structures by unlike material constitute, therefore, can produce the X line of different effective energies to each target structure by making electron beam hits.In addition, can carry out the change of X line effective energy at a high speed.

Therefore, the X spool device 107 of x-ray ct device 100 can shine the different a plurality of X lines of effective energy in multipotency scanning.

In addition, X spool device 107 can carry out multipotency scanning by changing position (by the position of finding a view) the change X line effective energy that X line effective energy is photographed at a high speed in single pass.

And, can constitute target by single collision angle, therefore, realize the shaping of target structure easily.

In addition, limit especially, can constitute target by 2 kinds, target structure more than 3 kinds or 4 kinds about the quantity of target structure and target matter.

(the 16th embodiment)

The 16th embodiment is the embodiment that sees through the detection of X line by a plurality of X thread detectors of different sensitivity.

Utilize Figure 38 that the x-ray ct device 100 of the 16th embodiment of the present invention is described.

Figure 38 is the figure of a form of expression X thread detector 127.

X thread detector 127 is made of a plurality of X thread detector 127-1～X thread detector 127-3 by multiple stratification.X thread detector 127-1～X thread detector 127-3 has the different X line detection devices of sensitivity separately.X thread detector 127-1～X thread detector 127-3 for example is the different X thread detector of sensitivity separately such as solid-state detector, detector

X thread detector 127-1～X thread detector 127-3 obtains data for projection 1159-1～data for projection 1159-3 by the X line 1157 of same effective energy respectively.Because the sensitivity of X thread detector 127-1～X thread detector 127-3 is different respectively, therefore, data for projection 1159-1～data for projection 1159-3 is equivalent to the data for projection obtained by the X line of different effective energies respectively.

In addition, X thread detector 127-1～X thread detector 127-3 also can circumference radially, any one party such as the circumferencial direction multiple stratification that makes progress, perhaps separate being provided with.And, but alternate configurations also when on detector face direction, carrying out multiple stratification.At this moment, each element can be used as separator mutually.But, when the reduction of the inhibition of considering X line amount and light exposure, wish in circumference multiple stratification upwards directly.

Like this, in the 16th embodiment, x-ray ct device 100 sees through the detection of X line by different a plurality of X thread detectors of sensitivity separately.Therefore, x-ray ct device 100 can not change X line effective energy, and according to the mode of shining the different a plurality of X lines of effective energy, obtains the view data corresponding with each X line effective energy (data for projection or reconstructed image).

(the 17th embodiment)

The 17th embodiment is parameter that meeting such as the wave filter (hereinafter referred to as wave filter) of tube voltage, band X spool, target matter, collision angle are exerted an influence to power spectrum and effective energy, is mapped with power spectrum or effective energy and carries out the embodiment of picture demonstration.

Figure 39 is that the picture of the 17th embodiment shows example.

The correspondence table 1671 that is showing power spectrum and effective energy and various parameters on the picture 170.In correspondence table 171, as entry " power spectrum ", " effective energy ", " tube voltage ", " wave filter ", " target matter ", " collision angle " are arranged, also can make " power spectrum " or " effective energy " corresponding with in " tube voltage ", " wave filter ", " target matter ", " collision angle " at least one.Also can only distinguish having changed above-mentioned parameter power spectrum or effective energy afterwards as correspondence table 171 by labelling.

And, on picture 170, show curve Figure 172, also can shape, first effective energy, second effective energy of above-mentioned first power spectrum, second power spectrum be illustrated.

In addition, as if input parameter in the correspondence table 171 of picture 170, then also can control X spool device 107 according to the parameter of this input.

According to present embodiment, parameter, power spectrum or effective energy can be mapped and confirm.

More than, with reference to accompanying drawing, the preferred implementation of x-ray ct device of the present invention etc. is illustrated, but the present invention is not limited to above-mentioned example.To those skilled in the art, in the disclosed technological thought scope of the application, be easy to expect various modifications or revise example, should be appreciated that these also belong in the technical scope of the present invention certainly.

And, in the above-described embodiment, utilized x-ray ct device, but be not limited thereto, also can be applicable to utilize in the CT device, X line photographic attachment of neutron ray, positron, gamma ray or light.

In addition, in the present embodiment, adopted to have one group of X spool and the general x-ray ct device of X thread detector, but also can be applicable to have in the multitube ball CT device of many group X spools and X thread detector.

(industrial utilizability)

Above-mentioned radiographic equipment and image processing program, so long as utilize a plurality of x-rays with different power spectrums to come the radiographic equipment of non-invasively internal structure of subject being photographed, then be not limited to medical purpose, also can be applicable to other industry purposes.

Claims (2)

1. radiographic equipment comprises:

The X line source, it shines the X line of first power spectrum and the X line of second power spectrum;

The X thread detector, it detects the X line of described first power spectrum that seen through subject and the X line of second power spectrum, exports the data for projection of first power spectrum and the data for projection of second power spectrum;

Control unit, its action to described X line source and described X thread detector is controlled;

Graphics processing unit, be a kind of data for projection and the data for projection of second power spectrum graphics processing unit of generating desirable image based on described first power spectrum, this graphics processing unit is based on the data for projection of described first power spectrum and the data for projection of second power spectrum, carry out interpolation processing, generate the data for projection of the power spectrum different with described first power spectrum and second power spectrum, and the data for projection that generates is reconstructed, generates and the described different corresponding reconstructed image of power spectrum; With

Display unit, it shows described reconstructed image.

2. radiographic equipment according to claim 1 is characterized in that,

Described graphics processing unit carries out logarithmic transformation to photon energy and X linear absorption coefficient, and photon energy or X linear absorption coefficient after changing based on this logarithm carry out linear interpolation.

Images