JPH08163441A - X-ray radiographing device - Google Patents

Abstract

PURPOSE: To measure nonlinearity of a sensitivity characteristics with high accuracy by using a sensitivity characteristic curve representing the camera operation mode and the multiplication factor so as to correct a camera output signal in a way that image density and intensity of X-ray have a linear relation. CONSTITUTION: The device is provided with a sensitivity characteristic measurement light source 5 to set optionally radiation light intensity in a noticed area of a camera image pickup pattern and with a sensitivity characteristic evaluation device 9 which measures plural combinations of intensity of the light source 5 and camera signal output when the camera operation mode and the multiplication factor are designated and uses the measurement data to record the sensitivity characteristic curve of the device to be calculated by using the measured data to a recording medium 10. The camera output signal is corrected in a way that the image density and the intensity of X-ray have a predetermined relation by using the sensitivity characteristic curve between the camera operation mode and the multiplication factor among sensitivity characteristic data. Then the sensitivity characteristic measurement light source 5 is controlled by a light source controller 8 and the sensitivity characteristic is evaluated while adjusting the light quantity made incident on the image pickup element to evaluate the nonlinearity with high accuracy.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray fluoroscopic / imaging device, and more particularly to an X-ray fluoroscopic / radiographic device using an X-ray television camera as a detector.
Regarding an imaging device.

[0002]

2. Description of the Related Art An apparatus of this type can convert an X-ray transmission image transmitted through a subject into a visible light image by an X-ray fluorescence multiplier, and can pick it up by a TV camera and collect it as digital image data. In this case, the X-ray sensitivity of the device is linear as shown in FIG. Further, in order to control the afterimage characteristic of the X-ray television camera, a bias light whose emission is controlled may be provided in the photographing sequence. The obtained digital image is used for diagnosis or the like in the image display device. At that time, for the purpose of improving the diagnostic ability, the image level with respect to the image density can be arbitrarily changed as shown in FIG.

As another technique using an X-ray television camera, for example, an X-ray three-dimensional image photographing method such as the rotary photographing method described in pages 113 to 118 of Volume 10 (1992) of Medical Imaging Technology. There is a device. FIG. 12 is an example schematically showing the same system. X-ray source 12
1 and the X-ray television camera 122 are rotated around the subject 123, and two-dimensional images are taken at certain angles and collected as digital images. Image distortion correction, density distortion correction, and the like are performed on the captured data, and an X-ray three-dimensional image of the subject is obtained by a three-dimensional image reconstruction algorithm.

In the above apparatus, the dynamic range of the X-ray television camera is smaller than that of the X-ray film or the photostimulable phosphor, and therefore, the dynamic range of the apparatus is insufficient. Here, the dynamic range of the device is an X that can be photographed by one fluoroscopy and photographing.
It is defined as the ratio of the maximum and minimum values of quantity. As a technique for solving this problem, for example, Japanese Patent Laid-Open No. 05-1
As disclosed in Japanese Patent No. 53496, an image pickup device using an avalanche multiplication function is used as an image pickup device of a television camera to increase the light receiving sensitivity and to expand the dynamic range of the apparatus, thereby increasing the range of X-ray intensity that can be taken. There is an X-ray fluoroscopy / imaging device that enables enlargement. In the invention of this application, the dynamic range of the apparatus is defined as the X-ray latitude.

Further, in the technique disclosed in the invention of this application, the information of the X-ray transmission image is stored in the data collecting / processing device as a digital value as an output video signal of the X-ray television camera device, and the stored function. The function to display the image data by performing image processing such as sensitivity correction on the image data is described.

[0006]

In the X-ray fluoroscopic / imaging apparatus having such a structure, the image level with respect to the image density is arbitrarily changed as shown in FIG. 11B for the purpose of improving the diagnostic ability. In order to realize the above, it is necessary that the relationship between the density of the image data to be changed and the X-ray intensity of the transmission image at the time of capturing is linear or capable of being linearly corrected. . In addition, in the energy difference processing and the three-dimensional image reconstruction processing using the two-dimensional image data in the X-ray three-dimensional image capturing apparatus, the density of the target image data and the X-ray intensity of the transmission image at the time of imaging are The relationship must be linear and equal between the image data used.

In the technique disclosed in the above-mentioned Japanese Patent Laid-Open No. 05-153496, by controlling the multiplication factor of the avalanche multiplication and the diaphragm of the optical system, the light receiving sensitivity and the dynamic range of the device can be adjusted according to the condition of the subject. It is possible to select. However, the X-ray sensitivity of the device changes non-linearly depending on the camera operating conditions and the multiplication factor. This is because the sensitivity of the image sensor has a non-linear characteristic. In FIG. 13, the camera operating conditions / multiplication factors are (a) 1050 scanning lines: 15 frames per second / multiplication 32 times, and (b) 1050 scanning lines: 30 frames / second / multiplication 32 times, ( c) 1050 scanning lines: sensitivity characteristics of the camera in the case of 30 frames per second / multiplication 16 times.

The state of density distortion also depends on the camera operating conditions and the multiplication factor of the device. The reason is as follows. The density distortion in the present technology occurs due to the synthesis of the following four main factors. (1) due to the spatial distribution of generated X-rays, (2) due to uneven sensitivity of the X-ray fluorescent multiplier or X-ray fluorescent plate, (3) due to an optical lens system,
(4) Due to the image sensor. Among these, the density distortion caused by (1) to (3) can be corrected by the conventional density distortion correction method. However, the density distortion due to (4) largely depends on the camera operating conditions and the multiplication factor,
Generally, the larger the multiplication factor, the larger the density distortion.

For these reasons, when the relationship between the image density and the intensity of X-rays is linearly corrected or the density distortion is corrected for the image data stored in the data collection / processing device, the image is corrected. The camera operating condition for capturing the data, the multiplication factor, and the sensitivity characteristic of the device under the condition are required as information, and the amount of information to be recorded as one set of image data is large, which is extremely difficult in practice. Therefore, a more practical correction means is needed.

Further, it has been found that the sensitivity of the image pickup device of this apparatus and the dependency of density distortion on the camera operating conditions and the multiplication factor largely depend on the individual difference of the image pickup device. This is because the avalanche multiplication effect of the image pickup device depends on the amorphous Se layer or Sb.
_This is due to the fact that it is very sensitive to the stacking state of ₂ S ₃ layers, which is characteristically shown in FIG. There is an individual difference of about 10% in the slope in the doubled region (d). Therefore, in order to be able to perform the above correction, means for accurately evaluating the above characteristics is required for each individual imaging element.

Further, in the X-ray television camera using the avalanche multiplication type image pickup device, the sensitivity and the afterimage characteristic differ depending on the multiplication factor, so that it is necessary to control the bias light in consideration of the difference in the characteristic.

[0012]

Of the inventions disclosed in the present application, a representative one will be briefly described below.
It is as follows.

Means 1. It has an X-ray generator, an X-ray TV camera, an imaging controller, and an image acquisition / processing device,
An X-ray fluoroscope / radiograph configured so that sensitivity and dynamic range for X-rays can be set by adjusting the multiplication factor and an optical diaphragm as an image pickup device of the X-ray television camera, which uses an avalanche multiplication function. In the device, a sensitivity characteristic measuring light source that arbitrarily sets the irradiation light intensity in the region of interest on the camera image pickup surface, and a combination of a plurality of combinations of the above light source intensity and camera signal output when the camera operation mode and multiplication factor are specified And a sensitivity characteristic evaluation device that records the sensitivity characteristic curve of the device calculated using the measured data in a storage medium, and the sensitivity characteristic curve of the camera operation mode and the multiplication factor of the sensitivity characteristic curve data. And a sensitivity correction means for correcting the camera output signal so that the image density and the X-ray intensity have a linear relationship. .

Means 2. In the configuration of the above means 1, a uniform light source in which the irradiation light intensity on the camera imaging surface is uniformly distributed, a light source control device for controlling the light source, and a density distortion image measured according to the camera operating conditions and the multiplication factor. And a density distortion evaluation means for storing the density distortion correction coefficient calculated from the result in the storage medium, and a camera at that time among the density distortion correction coefficients when performing fluoroscopy and photographing. It is characterized in that a density distortion correcting means for correcting the density distortion of the fluoroscopic image and the photographed image is provided by using the density distortion correction coefficient of the operation mode and the multiplication factor.

[0015]

According to the structure shown in the means 1, the light source for controlling the sensitivity characteristic is controlled by the light source control device, and the sensitivity characteristic is evaluated while adjusting the amount of light incident on the image pickup device, whereby the camera operation mode and the multiplication factor are increased. It is possible to accurately evaluate the non-linearity of the sensitivity characteristic of the device that depends on the individual difference of the image pickup device. Also,
The sensitivity characteristic of the device can be recorded by obtaining the sensitivity characteristic curve from the result and recording it in the storage medium.

Further, during fluoroscopy or photographing, the sensitivity correction means using the sensitivity characteristic curve can correct the camera output signal to an arbitrary sensitivity characteristic according to the camera operation mode and the multiplication factor.

Further, according to the configuration of the means 2, the uniform light source in which the irradiation light intensity is uniformly distributed on the image pickup surface of the camera is controlled by the light source control device, and the density distortion of the image is evaluated. By performing the above-described sensitivity correction, the density distortion of the image sensor can be evaluated, and it becomes possible to perform the density distortion correction according to the camera operation mode and the multiplication factor by using the density distortion correction coefficient during fluoroscopy or photographing. .

[0018]

1 is a block diagram showing an embodiment of an X-ray fluoroscopic / imaging apparatus according to the present invention.

As shown in the figure, this apparatus comprises an image pickup controller 1, an X-ray generator 2, an X-ray grid 3, an X-ray fluorescence multiplier 4, a light source 5, a lens system 6 including an optical diaphragm 6, and a television. It comprises a camera 7, a light source control device 8, a sensitivity characteristic evaluation device 9, a storage medium 10, a sensitivity correction device 11, an image acquisition / processing device 12, and an image display device 13. The image pickup device of the television camera 7 is an avalanche multiplication type image pickup tube, the light incident surface of which is an amorphous selenium photoconductor, and its multiplication factor is controlled within a certain range by the voltage value applied to the photoconductive film. it can. The imaging control device 1 generates the X-rays in the X-ray generation device 2,
The image pickup field size selection of the X-ray fluorescence multiplier tube 4, the operating conditions and the multiplication factor of the lens system 6 including the optical diaphragm, the bias light 61, and the television camera 7 are controlled. The X-ray transmission image is
It is converted into a visible light image by the X-ray fluorescence multiplier tube 4. In addition,
Instead of the X-ray fluorescence multiplier tube 4, it is also possible to use an X-ray fluorescence plate.

The light source 5 is, for example, an LED as shown in FIG.
21 and the light diffusing glass 22, the emission intensity can be controlled by the output voltage of the light source control device 8 or the like. If the wavelength of the emitted light is similar to the wavelength of the output light of the X-ray fluorescence multiplier 4, the primary quantum efficiency of the photoelectric effect in the photoconductive film is the same as in the case of capturing an X-ray transmission image. Because,
It is easy to evaluate and becomes good. The light source 5 can be removed at times.

The light source control device 8 stores the relationship between the incident light intensity of the camera and the output voltage in advance, and has the function of reproducing the desired incident light amount of the camera by adjusting the output voltage. The sensitivity characteristic evaluation device 9 evaluates the sensitivity characteristic of the device by controlling the light source control device 8, the photographing control device 1 and the television camera 7, and records it in the storage medium 10 as a sensitivity characteristic curve. The output of the TV camera 7 is
It is digitized in the processing unit 12 and recorded as digital information. During the digitization process, the sensitivity correction device 11 uses the camera operating conditions at the time of imaging and the sensitivity characteristic of the multiplication factor among the sensitivity characteristic curve data of the device stored in advance in the storage medium to determine the image density and the X-ray intensity. It also has a function of correcting the camera output signal so as to have a linear relationship. The image display device 13 has a function of correcting the image output for the image data to be displayed in response to the user's request when displaying the captured image.

The sensitivity characteristic of the device is recorded in the storage medium 10 as a sensitivity characteristic curve shown in FIG. 3 as an example. As an example, description will be made using a case where the camera operation mode is 1050 scanning lines, 15 frames per second scanning, and multiplication 32 times.

First, preset parameters: Imax, Imi
Set n and Ns. This setting parameter is determined as follows according to the camera operation mode and the multiplication factor.
First, Imax is the maximum signal current amount of the television camera 7. Next, Imin is a minimum signal current amount for evaluating the sensitivity characteristic, and since the sensitivity of the avalanche multiplication type imaging device shows a linear characteristic in a region where the signal current is sufficiently low, a certain signal current in this linear region is shown. Use quantity for Imin.
Ns is the total number of sample points for measuring the sensitivity characteristic.

Then, such a sensitivity characteristic curve is obtained by the following method. FIG. 4 shows the flow of means for evaluating the sensitivity characteristic and storing the sensitivity characteristic curve. First, the television camera 7 is set to a camera operation mode to be evaluated and a multiplication factor (step 1), and setting parameters given to the storage medium are: maximum signal current amount Imax, minimum signal current amount Imin, total number of sampling points Ns. (Step 2). Next, the maximum value L in the light amount region for measuring the sensitivity characteristic
max is determined by the following method. The maximum signal current amount Imax of the television camera 7 is, for example, Imax = 2.5 (μA). The light quantity of the light source 5 is scanned, the light quantity incident on the camera that reproduces the maximum signal current Imax is measured, and this light quantity is adopted as the maximum value Lmax in the light quantity region for measuring the sensitivity characteristic. Next, the minimum value Lmin in the light amount region for measuring the sensitivity characteristic is determined by the following method. For example, the minimum signal current amount Imin =
It is set to 20 (nA). The light quantity of the light source 5 is scanned, the light quantity incident on the camera that reproduces this minimum signal current Imin is measured, and this light quantity is used as the minimum value Lmin in the light quantity region for measuring the sensitivity characteristic.
To adopt.

By the above procedure, the light amount region for measuring the sensitivity characteristic can be determined (step 3). In this region, the sensitivities of several sample points are measured, and the sensitivity characteristic curve of the apparatus as shown in FIG. 3 is determined by the interpolation using the sensitivities of those sample points as the basic data (step 4) (step 5). The result is stored in the storage medium 10 (step 6).

Here, the sample points for measuring the sensitivity can be determined by the following method. First, for example, assume that the total number of sample points given in advance is Ns = 5. The sample point is determined by dividing the logarithm into equal parts in a light amount region for measuring the sensitivity characteristic. White circles in FIG. 3 are examples of sample points determined by equal division. Further, since the sensitivity of the avalanche multiplication type imaging device becomes non-linear as the signal current increases, it is effective to determine so that the density of the sampling points becomes higher as the signal current increases. The black squares in FIG. 3 are examples of sample points determined by this method. From the above, the sensitivity characteristic curve is obtained.

The total number Ns of sample points determines the accuracy of the sensitivity characteristic obtained by interpolation. Since the nonlinearity of the sensitivity of the avalanche multiplication type imaging device increases as the multiplication factor increases, it is necessary to increase the total number Ns of sampling points as the multiplication factor increases. Therefore, the method of determining the total number Ns of sample points so as to increase as the multiplication factor increases becomes extremely effective.

The sensitivity is corrected by using the sensitivity characteristic curve shown in FIG. When using this device with fixed camera operating conditions and multiplication factors, only the sensitivity characteristics of the device under those conditions are required, so image data is recorded without sensitivity correction.
There is a method of performing sensitivity correction during image display and image processing. However, in general, it is effective to use the sensitivity correction device 11 in the image collection / processing device 12 to perform sensitivity correction on the image data and then record the image data as image data. Based on this, an example of sensitivity correction of a captured image will be described below. When the subject 51 shown in FIG. 5 is photographed under the conditions of camera operation: 1050 scanning lines and a multiplication factor of 32, the image density distribution on the line segment a-b in FIG. This is the case as shown in 7. The figure shows that, although the steps of the stairs of the subject 51 are the same, they are not photographed as they are, but they are photographed while being sequentially narrowed in one direction. When the image density is corrected using the sensitivity characteristic curve of the apparatus of FIG. 3, the image density on the line segment a-b of FIG.
And the non-linearity can be corrected.

Here, the sensitivity characteristic curve shown in FIG. 3 and FIG.
The relationship between the image density distribution before correction shown in FIG. 8 and the image density distribution after correction shown in FIG. 8 will be described.

First, a linear correction line 31 is set based on the sensitivity characteristic curve shown in FIG. Then, the camera output when the subject 51 is photographed is as shown in FIG. 7, and in this case, the camera output for the X stage is x.

Again, from the characteristic of the correction line 31 shown in FIG. 3, the output x'for the input x is obtained. This x'is the camera output in the image density distribution of the correction line to which it corresponds.

When the sensitivity correction is not linear and is corrected as desired by the operator, it is performed as follows.

In FIG. 3, the correction line 32 desired by the operator.
Set. For its input x, obtain its output x ″.
This x "is the camera output on the correction line 32 desired by the operator. The corrected image density distribution is shown in FIG.

Although the above description is for some pixels, the same processing is performed for all pixels by, for example, computer processing to obtain the corrected image density distribution as shown in FIG. .

An example of the control method of the bias light 61 in this apparatus will be described. The amount of light emitted from the bias light 61 has an optimum value depending on the camera operating conditions and the multiplication factor, and is therefore controlled by the photographing control device 1 through the light source control device 8. When the bias light 61 is used, the image collection / processing device 12 uses the sensitivity correction device 11 to perform sensitivity correction on the image data as described above, and then subtracts the image output by the bias light output from the image data. Record as image data. The light source 5 can also be used as a bias light.

Next, an embodiment of density distortion correction according to the present invention will be described. FIG. 9 illustrates a method of density distortion correction. FIG. 9A shows the original concentration distribution. When density distortion exists in the device as shown in FIG.
By multiplying by the correction coefficient of (c), the correction is performed as shown in FIG. Here, it is important to obtain the correction coefficient of FIG. As described above, the density distortion in this apparatus occurs due to the synthesis of the following four main factors.
(1) due to spatial distribution of generated X-rays, (2) due to uneven sensitivity of the X-ray fluorescent multiplier 4 or the X-ray fluorescent plate,
(3) by the optical lens system 6 and (4) by the image sensor. Of these, (1) and (2) are X-ray imaging such as the distance between the X-ray generator 2 and the X-ray fluorescence multiplier 4, the tube voltage / tube current, and the field size of the X-ray fluorescence multiplier 4. It depends on the condition, (3) depends on the diameter of the optical diaphragm, and (4) depends on the camera operating condition and the multiplication factor. Therefore, the density distortion correction in this apparatus is performed by the following procedure. First, the density distortion of (3) is evaluated by the lens system alone while changing the optical aperture diameter, and the density distortion correction coefficient of (3) alone is stored in the storage medium as a function of the optical aperture diameter. Hereinafter, this correction coefficient is referred to as Kl. Next, (4) independent image distortion is evaluated. Device Configuration In FIG. 1, the light source 5 is designed so that the light incident on the camera is uniform. There is also an example in which a uniform light source for evaluating density distortion and a light source for sensitivity characteristic measurement are prepared separately, and in this case, the light source for sensitivity characteristic measurement may be a point light source.

An image of the light source 5 is taken under certain camera operating conditions and multiplication factors. The above-described sensitivity correction is applied to the image pickup result, and the density distortion correction coefficient Kc of the image pickup element alone under the camera operating condition and the multiplication factor is obtained from the result and Kl and stored in the storage medium. Finally, the density distortion of the entire X-ray apparatus was evaluated, and from Kl and Kc,
The density distortion correction coefficient Kx of (1) and (2) is obtained.
The overall density distortion correction coefficient is the integration of Kl, Kc and Kx.

According to the present method, once Kx is obtained, it is not necessary to measure the density distortion again when the optical diaphragm system of the apparatus, the camera operating condition and the multiplication factor are changed within a range where the X-ray photographing condition does not change thereafter. Therefore, it is effective when the dynamic range of the device is changed and used. In addition,
For simplification, it is possible to omit the optical aperture diameter dependency of (3) as an approximation.

An embodiment in which the present invention is applied to an X-ray three-dimensional image capturing apparatus will be described. FIG. 10 is an example of a configuration diagram of this embodiment. In this apparatus, the sensitivity characteristic and the density distortion correction coefficient of the apparatus are stored in advance by the method of the present invention, and after capturing a two-dimensional image of the subject 101, the image data is linearly corrected by the sensitivity correction to obtain the density distortion. Is corrected, the bias light component is subtracted, and logarithmic conversion is performed. In addition, the image distortion is corrected by using a conventional method. The above processing is applied to each captured image data, and an X-ray three-dimensional image is obtained by three-dimensional reconstruction processing. It should be noted that in the present method, the above image data can be corrected even when the multiplication factor is changed for each shooting direction with respect to the subject 101.

[0040]

As is apparent from the above description,
According to the X-ray fluoroscopic / imaging apparatus of the present invention, it becomes possible to accurately measure the non-linearity of the sensitivity characteristic, which is a problem when an avalanche multiplication type imaging device is used.

Further, based on the result, the sensitivity characteristic can be arbitrarily corrected.

Further, the image density distortion can be corrected.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing an embodiment of an X-ray fluoroscopic / imaging apparatus according to the present invention.

FIG. 2 is a diagram showing an embodiment of a light source for sensitivity characteristic measurement used in the present invention.

FIG. 3 is a diagram showing an operation condition of a camera: the number of scanning lines is 1 in the present invention.
9 is a graph showing a result of obtaining a sensitivity characteristic curve under the condition of 050 lines / 15 frames / sec scanning and multiplication 32 times.

FIG. 4 is a flow chart showing the flow of an embodiment in which the sensitivity characteristic of the X-ray fluoroscopic / imaging apparatus according to the present invention is evaluated and the sensitivity characteristic curve is recorded.

FIG. 5 is an explanatory diagram showing an example of a subject used in the present invention.

FIG. 6 is a diagram showing an image obtained as a result of photographing an object in which the X-ray transmission amount changes stepwise with equal intervals using the X-ray fluoroscopic / imaging apparatus of the present invention.

7 is a diagram showing an image density distribution on a line segment ab in FIG.

8 is a diagram showing an image density distribution on a line segment ab when the image of FIG. 6 is subjected to sensitivity correction by the method of the present invention.

FIG. 9 is an explanatory diagram showing an image distortion correction method in an X-ray fluoroscopic / imaging apparatus according to the present invention.

FIG. 10 is a diagram showing an embodiment in which the present invention is applied to an X-ray three-dimensional image capturing apparatus.

FIG. 11 is a diagram illustrating a sensitivity characteristic of a conventional X-ray device and a conventional technique of density correction performed when an image is displayed.

FIG. 12 is a diagram illustrating a conventional technique of an X-ray three-dimensional image capturing apparatus.

FIG. 13 is a diagram showing an example of sensitivity characteristics of an X-ray apparatus using an avalanche multiplication type imaging device.

14 is a diagram showing an image density distribution on line ab when the image of FIG. 6 is subjected to sensitivity correction by the method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Imaging control device, 2 ... X-ray generator, 3 ... X-ray grid, 4 ... X-ray fluorescence multiplier, 5 ... Light source, 6 ... Lens system including an optical diaphragm, 7 ... Television camera, 8 ... Light source control Equipment, 9
... sensitivity characteristic evaluation device, 10 ... storage medium, 11 ... sensitivity correction device, 12 ... image collection / processing device, 13 ... image display device.

Claims (9)

[Claims] 1. An X-ray generator, an X-ray television camera,
The image pickup control device and the image acquisition / processing device
In an X-ray fluoroscopic / imaging apparatus configured to be capable of setting sensitivity and dynamic range for X-rays by using an avalanche multiplication function as an imaging element of a line television camera and adjusting the multiplication factor and an optical diaphragm. , Sensitivity characteristics measurement light source that arbitrarily sets the irradiation light intensity in the area of interest on the camera imaging surface, and when the camera operation mode and multiplication factor are specified Measure the relationship between the above light source intensity and camera signal output for multiple combinations Then, using the sensitivity characteristic evaluation device for recording the sensitivity characteristic curve of the device calculated using the measurement data in the storage medium, and the sensitivity characteristic curve of the camera operation mode and the multiplication factor of the sensitivity characteristic curve data, An X-ray transparent apparatus having a sensitivity correction means for correcting the camera output signal so that the image density and the X-ray intensity have a predetermined relationship. Vision / shooting device. 2. The X-ray fluoroscopic / imaging apparatus according to claim 1, wherein the predetermined relationship is a linear relationship. 3. A pre-stored setting parameter is read from the selected camera condition, a sensitivity characteristic sample point is determined from this setting parameter, and each sample point is measured and data interpolation is originally performed. The X-ray fluoroscopic / imaging apparatus according to claim 1, wherein the sensitivity characteristic curve data is obtained by: 4. A uniform light source in which the intensity of irradiation light on a camera imaging surface is uniformly distributed, a light source control device for controlling the light source, and a density distortion image measured according to a camera operating condition and a multiplication factor. A density distortion evaluation unit that performs sensitivity correction using a sensitivity characteristic curve and stores the density distortion correction coefficient calculated from the result in a storage medium, and a camera operation mode of the density distortion correction coefficient at that time during fluoroscopy and photographing. 4. An X-ray fluoroscope according to claim 1, further comprising a density distortion correction means for correcting the density distortion of the fluoroscopic image and the picked-up image by using the density distortion correction coefficient of the multiplication factor. / Imaging device. 5. The X-ray fluoroscopic / imaging apparatus according to claim 4, wherein the uniform light source is used as the light source for measuring the sensitivity characteristic. 6. The light emission wavelength of either or both of the sensitivity characteristic measuring light source and the uniform light source is approximate to the output wavelength of the fluorescent portion of the X-ray television camera. 5. The X-ray fluoroscopic / imaging apparatus according to any one of 5. 7. A bias light provided in the lens system, and a light source control device for controlling the light emission of the bias light according to a camera operating condition and a multiplication factor during fluoroscopy or photographing. 6. The X-ray fluoroscopic / imaging apparatus according to any one of 6. 8. The X-ray fluoroscopic / imaging apparatus according to claim 7, wherein the bias light is used as the light source for measuring the sensitivity characteristic or the uniform light source. 9. A means for capturing a two-dimensional transmission image of a subject at an arbitrary angle while the X-ray generator and the X-ray television camera rotate around the subject, and a plurality of obtained two-dimensional images. 9. An X-ray fluoroscopic / imaging apparatus according to claim 1, further comprising means for performing three-dimensional image reconstruction from the above.