JPS61107341A - X-ray television photographing device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention belongs to the technical field of diagnostic medical devices, and in particular,
The technical field lies in the field of X-ray television imaging devices, such as digital fluorography devices and X-ray fluoroscopy devices.

[Technical background of the invention and its problems] Conventionally, in the xII television photographing device, Ili! XI regarding the target part of the subject to be imaged! Transparent images can be displayed on a display device, such as a mo2! Display 1: It is common to confirm the target area by looking at the target area. For example, as shown in ff131m, the digital Norologranoi device
The Xn image obtained when the X-rays emitted from the X-ray tube 12 pass through the subject P is fluoresced on the input phosphor screen of the image intensifier (hereinafter also referred to as ■ and ■) 1. This fluorescent image is appropriately amplified to produce an I.
11 output phosphor screen as an optical image, and this optical image is sent to a television camera 3 via an optical system (tandem lens system) 2.
The video signal output from the television camera 3 is sent to the camera controller 4 (stored in the memory in the digital fluorography processor 5, and then sent to the digital 70
The signal-processed video signal and the ruby scanning signal are output from the log graph live setza 5 to the television monitor 6, and an X-ray fluoroscopic image is displayed on the television monitor 6.
It is configured to record an X-ray fluoroscopic image, or to record an X-ray fluoroscopic image on an X-ray film using a multi-format camera 8.

Furthermore, the digital fluorography apparatus is capable of continuously transmitting X-rays from the X-ray tube 12 in both a simple fluoroscopic imaging mode and a fluoroscopic imaging mode in which digital signal processing is performed on a video signal obtained by continuous XSL irradiation. Exposure is performed as follows. That is, from the digital fluorography processor 5, the continuous XI! 1 liter of radiation
A control signal for LD is output to the X-ray controller 10, and a high voltage is continuously applied from the high voltage generator 11 to the Xsl is continuously irradiated from 12.

In addition, in digital fluorography equipment, intermittent
Fluoroscopy III requiring radiation exposure and digital signal processing
In the case of the X-ray mode, intermittent X-ray irradiation is performed as follows. That is, the f digital fluorography processor 5 intermittent Xllll1il! The control signal that controls the
By intermittently applying air pressure from the am pressure generator 11 to the XII tube 12 according to the rate signal output from the X-ray controller 10 and from the X-ray controller □゛・10, The X-rays are 111 intermittently! l) 1.

Furthermore, in the digital fluorography apparatus,
As shown in Figure 4, like the conventional X-ray fluoroscopic imaging device,
! I-■ indirect photography may be performed using the -1-direction spot camera 15 and the I-■ indirect cine camera 14,
Even during this 1.1 indirect @shadow period, a transparent image is observed by the television camera 3 and the television monitor 6.

Therefore, in the above-mentioned digital Norologranoy device, there is a simple fluoroscopic mode, a fluoroscopic 81 projection mode during indirect photography, and a continuous XI! The amount of light incident on the television camera 3 per unit RFI differs depending on the radiation exposure mode or the fluoroscopy mode requiring intermittent XM radiation and digital signal processing, etc., and therefore the video output level from the television camera 3 also differs. becomes.

Furthermore, the amount of light incident on the television camera 3 per unit time also differs due to variations in the conversion coefficients of I and ■ of the same model, or differences in the conversion coefficients of 1'-1 of different models. Furthermore, the amount of light incident on the television camera 3 per unit time also changes due to a decrease in the conversion coefficient due to secular change in ■ and ■, and a change in the conversion coefficient due to switching of the input field of view diameter in ■ and ■.

In order to perform optimal monitoring, the output level of the video signal from the television camera 3 must always be constant. However, since the optimal Xa irradiation conditions are determined depending on the surgical procedure, it is not preferable to fine-tune the XI irradiation conditions in order to maintain the output of the television camera 3 at a constant level.

Therefore, in a conventional digital fluorography device or an X-ray fluoroscopic imaging device, as shown in FIG. Aperture controller 1 that controls 16
3 (indicated by the same number in FIG. 3), the diaphragm controller 13 adjusts the diaphragm 16 so that the amount of light incident on the television camera 3 per unit time is constant. This method has been proposed by the same applicant (see Japanese Patent Laid-Open No. 149743 of 1982).

However, in the above method, the aperture diameter of the aperture 16 is
When the secondary lens 19 of the optical system is opened close to the aperture diameter,
Peripheral light (
There is a problem that the ratio of 6) is significantly reduced. Also, the aperture diameter of the diaphragm 16 is set to 1/2 of the aperture diameter of the secondary lens 19.
When reduced to below, the primary lens IF3 and the secondary lens 19
The problem is that the absorption and scattering of light by the photopic I tube 20, which is inserted between the There are also points.

In addition, semi-transparent mode is used as a positive means for transmitting light amount w1 to the TV camera 3 when switching from the transparent perspective mode to the transparent mode using indirect photography. There is 1117.

However, the light transmittance to the 7Levy camera 3 is 1
Since it is limited to one type per semi-transparent It17,
Even if it is possible to correct the amount of light by switching modes using the semi-transparent 'A' mirror 17, each It is not possible to correct the amount of light incident on the television camera 3 per unit time based on the difference. Therefore, even if multiple or several semi-transmissive mirrors 17 are arranged to make it possible to correct or correct the amount of incident light, it is impractical due to the limited capacity of the X-ray optical system, and the semi-transmissive mirrors 17 are The maximum number of 17 cards that can be used is two.

In addition, in digital fluorography equipment,
Correction of the amount of light incident on the television camera 3 per unit time for the fluoroscopy mode using continuous X-ray irradiation, which requires digital signal processing, and the fluoroscopic m-shadow mode, using intermittent X-ray irradiation, which requires digital signal processing, is conventional. , semitransparent vA
This was done by attaching a light attenuation filter to 17.

However, such a correction means has the drawback that the correction of the amount of light incident on the television camera 3 per unit time during the (1)/I indirect W award must be sacrificed.

In addition, variations in conversion coefficients in 1 and ■ of the same model,
The unit for the TV camera 3 according to the difference in the conversion coefficient between different models of I-1, the decrease in the conversion coefficient due to aging of ■ and ■, and the change in the conversion coefficient due to switching of the field of view diameter of I-■. The amount of incident light per hour is corrected using an auto iris control method.

However, in a 1-digital NO logrono device, if the aperture diameter is set close to the upper or lower limit of the usable range of the aperture diameter by varying the aperture 15 using the auto iris control method in conjunction with switching between the two modes, ]・1
It becomes impossible to perform appropriate light amount correction corresponding to changes in the conversion coefficient.

[Object of the Invention] This invention has been made in view of the above-mentioned circumstances, and is an object of the present invention.
WA TV Fisho device, surgical procedure.

Transmission, Transmission 81 Despite the differences in MrJ shadow [-] and the 1.1 conversion coefficient due to various causes, it is possible to improve the video output of the television camera by adjusting the amount of light incident on the television camera per unit time. It is an object of the present invention to provide an X-ray television display device having an optical system that can always operate in a constant state.

[Summary of the Invention 1] The outline of the present invention for achieving the above object is to control the ability to enter and exit parallel light rays formed by a primary lens,
And, when the light transmittance of the optical filter having the maximum light transmittance is 8, the light transmittance of the other optical filters is A2'' (
m is a positive integer. That is.

[Embodiment of the Invention] FIG. 1 shows the configuration of an X-ray television commemorative device, such as a digital 70 Logranoi device, which is an embodiment of the present invention.

The digital fluorography apparatus shown in FIG. 1 differs from the digital fluorography apparatus shown in FIG. 3 in the following points.

That is, the primary lens 18 and ■・1 of the primary lens 18
In addition to the photo pickup 20 which is arranged on the opposite side of the lens 1 and which detects the amount of light transmitted through the primary lens 18, and the secondary lens 19, there is also a diaphragm 21 which changes the amount of light of the optical image.
and a plurality of optical filters "-1°F-2, . . . , F-n, which can enter and exit the parallel rays formed by the primary lens 18 and attenuate the amount of the parallel rays. 2
3., an aperture control W unit 24 which outputs an aperture drive signal which controls the aperture diameter of the aperture 16 according to a control signal output from the digital fluorography processor 5, and an output from the digital fluorography processor 27. ,
Transparent mode, digital signal processing J1! Depending on the difference between the fluoroscopic image mode using continuous X-ray exposure which requires 1.
A filter drive control unit 25 outputs a -C noiler drive control signal in synchronization with a command signal for moving F-2, -, f-n into and out of a parallel beam, and a filter drive control unit 25 outputs a -C noiler drive control signal. The optical filters F-1, F-2゜..., F-n are alternately driven by the noilter drive i1J fllJ signal.
Or a filter drive bag that moves multiple sheets in and out of parallel light beams at once! 26-1゜26-2. ..., 26-n and
- Outputs the command signal to the filter drive control section 25 and the aperture control section 24 according to various modes specified by a console box (not shown), and also outputs the command signal to the automatic exposure control section 9
It also has a function of outputting the command signal to the aperture controller 24 based on information about the amount of light transmitted through the primary lens 18 detected by the photo pickup 20 and input via the X-ray controller 10. digital shift 00
A graphics processor 27 is also provided.

The optical filters F-1, F-2, . . . F-n are each in the following III category. The t-line is also in a relationship with the maximum (m is a positive integer) of the optical filters F-1, F-2,...l''-n. Considering the range, for example, the attenuation rate is set equal to the ratio of the minimum value to the maximum value of the attenuation rate adjustable by the aperture 21. That is, the optical filters F-1, F-2, . . .
・The light transmittance decreases in the order of F−n, and
Variable attenuation rate W by the twill 21! If the angle is set from 1.9 (open aperture) to 0°1 (1/10 of the open aperture), the light transmittance of the optical noirter F-1 will be 0.1, and the optical filters F-2 and F- The light transmittance of optical noirters F-3, F-4, etc. represented by n is n A 2″, respectively.
From the relationship, 0.12 and 0.14.0.1"...

In this way, optical filters F-1, F-2,...F-
If the light transmittance is set to n, it is possible to continuously attenuate the rays of the parallel light beam using the minimum number of optical filters and the diaphragm 21, as will be described in detail later.

In FIG. 1, the same reference numerals as those in FIG. 3 have the same functions as shown in FIG. 3, so the explanation thereof will be omitted.

Next, the above effects will be described.

First, the aperture 21 and optical filters F-1, F-2 and F-
The variable range of the optical attenuation rate in combination with a total of three optical noilers of F-3 represented by F-3 will be explained with reference to FIG.

FIG. 2 is an explanatory diagram showing the variable range of the optical attenuation rate that can be realized by the aperture and the optical filter.

Note 1. Optical filter F-1. The light transmittance of F-2.1-3 is 0.1, 0.12, and 0.14, respectively.

Com1 in the figure is a variable range of the light attenuation rate by only the aperture 21, and has a variable range of attenuation rate from 1.0 to 10-1. Further, GO11+2 is a variable range of the optical attenuation rate that can be realized by the combination of the filter 21 and the optical filter F-1, and has a variable range of the optical attenuation rate from 10 to 10-2. Similarly, Com3
Com4 is the variable width of the optical attenuation rate that can be realized by the combination of the aperture 21 and the optical filters F-1 and F-2, C0115 is the aperture 21 and optical filter F-3
GO11, a variable range of optical attenuation rate that can be realized in combination with
16 is a variable width of the optical attenuation rate that can be realized by the combination of the diaphragm 21 and the optical filters F-1 and F-3, and Cova7 can be realized by the combination of the aperture 21 and the optical filters F-2 and F-3. The variable width of the optical attenuation rate, C0Il18, is comparatively 21 and the optical filter F~1. This is the variable range of the optical attenuation rate that can be realized by any combination of l-2 and F-3. Therefore, the optical filters 91-1. The optical attenuation rate varies from 1.0 to 10- depending on the combination of the three optical filters r-2, 1-3 and the aperture 21.
It can be changed continuously up to 8.

Control of the aperture diameter of this diaphragm 21 and the optical filter F
-1, F-2, and F-3 are inserted into the parallel light beam by the aperture control unit 2II 24. For example, the filter drive illumination device 25 performs the following operation.In the digital fluorography apparatus shown in FIG. 1, and by appropriately arranging the light attenuation noiler 22 within the parallel light beam, the output level of the output video signal of the television camera 3 is set to 1 with respect to the light ai oo transmitted through the primary lens 18. Suppose that

In the case of fluoroscopy with 161% continuous X-rays which requires digital signal processing @shadow mode, when the amount of light passing through the primary lens 18 is 10 times that of the optimum state, or 1000, an optical noilter F with a light transmittance of 0.1 A command signal for inserting -1 into the parallel beam is sent to the digital fluorography processor 2.
7, the filter drive controller 25 outputs a filter drive control signal to the filter drive device 26-1, and an optical filter F-1 with a light transmittance of 0.1 is placed within the parallel beam. be done. For this reason, 1
Even if the amount of light transmitted through the next lens 18 is 1000, it is attenuated to 1/10 by the optical filter F-1 with a light transmittance of 0.1. A video signal with a level of .

In addition, due to the aging of ■・11, the change
If the number drops to 415, the photo pickup 20
In this case, the light 9 passing through the primary lens 18 changes from 100O to 80O
When the detection signal is output to the digital fluorography processor 27 via the automatic exposure control unit 9 and the X-ray control unit 10, the digital fluorography processor 27 issues a command signal. is output to the diaphragm control unit 24, and the aperture diameter of the diaphragm 21 is set to an intermediate value between the upper and lower limits, and is opened to 1.25 times the specified value by the diaphragm drive signal output from the diaphragm control unit 24. , the amount of light passing through the aperture 21 is set to 1000, and then the photons are reduced to 1000 by the optical filter F-1 with a light transmittance of 0.1.
As a result, the television camera 3 outputs a video signal of level 1, as in the case of the optimum state.

In addition, ■・11 has two types of input field of view diameter (9 inches and two-inch) and the conversion coefficient has changed to 415 due to aging.
Digital flow equipped with dual r-t reduced to
] In the graphic equipment, when the visual field is switched from the input field of view of 9 inches to the manual field of view of the two-way camera in the shadow mode, the conversion coefficient of l-11 is 49/81, so the photo pickup 20 uses the primary lens 1.
When it detects that the amount of light passing through 8 has decreased to 800 x 49/81 and outputs the detection signal to the digital fluorograph processor 27, the command signal output from the digital fluorograph processor 27 is input. The aperture diameter of the aperture 21 is set to a value between the upper and lower limits by the aperture drive signal output from the aperture control unit 24.
By opening the aperture to 607 times, the light passing through the aperture 21 is set to ff11000, and then the light amount is attenuated to 100 by the optical filter F-1 with a light transmittance of 0.1, and as a result,
The television camera 3 outputs a level 1 video signal.

Note that the ratio of the maximum intensity to the minimum intensity of the optical image on the output surface of I.11 under various photographing conditions is usually 108:1, but as mentioned above, the ratio of the maximum intensity to the minimum intensity of the optical image on the output surface of I.
1, F-2, and F-3, the input level to the television camera 3 becomes the optimum level.

In this way, in the device of this embodiment, for example, the R shadow [-
The input level to the TV camera 3 can be adjusted to the optimum level regardless of the difference in the code, the radiation conditions, the difference in the part of the image, the type of subject or specimen, etc., so diagnosis without deterioration is possible. , it is possible to obtain transparent images with excellent performance. In addition, as the width of the attenuation m that requires adjustment increases, an optical filter with a small light transmittance is required, which inevitably increases the number of optical filters. The aperture 21 has a ratio of the minimum value to the maximum value of 0°1, and its light transmittance is 0°1, 0.12, respectively.
Three optical noirters F-1, F-2, F- with a value of 0.14
3, it is possible to continuously change the optical attenuation rate from 1°0 to 1.0−8. That is, when the light transmittance of the optical filter having the maximum light transmittance is A,
The light transmittance of other optical filters is A2. Δ4. All,・
... A2″1,, (m is a positive integer), the optical filter (=I is not wasted, and the minimum number of optical filters and aperture 21
This allows the amount of parallel light to be continuously attenuated. Therefore, the optical system 23 is made smaller.

This is extremely advantageous in equipment strikes, etc.

Although one embodiment of the present invention has been described above, it goes without saying that the present invention is not limited to the above-mentioned embodiment, and can be modified as appropriate within the scope of the gist of the present invention.

For example, in the above embodiment, the optical filter with the maximum light transmittance is F-1, and this optical filter F-
Although the light transmittance of 1 is set equal to the ratio of the minimum value to the maximum value of the attenuation rate adjustable by the aperture 21, it may be set to be slightly larger than this ratio. If set in this way, for example, C0Il11 to Co
An overlapping portion can be provided in the variable width of the optical attenuation rate for each combination of m8. In an actual device, in order to more reliably adjust the amount of light, it is preferable to slightly increase the overlap in the variable width of the optical attenuation rate for each combination as described above.

Note that there is no restriction on the order in which the plurality of optical filters are arranged.

In addition, the mode switching in the above embodiment was from a simple fluoroscopic mode to a fluoroscopic imaging mode using continuous X-ray exposure; ! Even when switching to fluoroscopic photography mode etc. by exposure, fine adjustment of the amount of light and optical filters F-1, F by using optical filters F-1, F-2°..., F-n or by using aperture 21 are performed.
-2,...

By coarsely adjusting Fn, the output level of the video signal from the television camera 3 can be made constant.

[Effects of the Invention] According to the invention described in detail above, in an X-ray television imaging device such as a digital radiographic device or an ? 52 shadow mode, continuous X requiring digital signal processing
Clairvoyance through 16-hour shooting! ! i2 shadow mode, 'rB viewing mode with intermittent X-ray irradiation that requires digital signal processing, by switching between radiography modes with significantly different X-ray exposure conditions, or by converting between different models of ■ and I. 1 due to differences in coefficients, a decrease in the conversion coefficient due to aging of r-1, and changes in the conversion coefficient due to switching of the input field of view diameter of I-f.
Even if the amount of light passing through the lens changes, the amount of light incident on the image pickup tube in the television camera per unit time is kept constant, thereby making it possible to keep the video output of the television camera constant. By keeping the video output of the television camera constant, digital image processing in the digital fluorography processor can be performed appropriately, and fluoroscopic images without deterioration can be obtained, which greatly contributes to improving medical diagnostic performance. be able to.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an X-ray television photographing device that is an embodiment of the present invention, and FIG. 2 is an explanatory diagram showing the variable range of the light attenuation rate that can be realized by the aperture and optical filter included in the device of this embodiment. , Figure 3 shows the conventional digital
FIG. 4 is a block diagram showing the main parts of a conventional digital fluorography device that performs IF indirect VRI imaging, and FIG. 5 is a block diagram showing the optical system of a conventional X-ray television imaging device. . 1... Image intensifier, 3... Television camera, 12... X-ray tube, 18... Primary lens, 1
9...Secondary lens, 21...Aperture, F-1, F-2,..., F-n...Optical filter,
23...Optical system. '(7 Agent Patent Attorney Masayoshi Misawa: ;,%1 r
・ 1 (1-2- Fig. 4

Claims (4)

[Claims] (1) An image intensifier that converts the X-ray image obtained when the X-rays emitted from the X-ray tube pass through the subject into an optical image, and the optical image from this image intensifier. In an X-ray television photographing apparatus having a secondary lens and a television camera that photographs through an optical system having a secondary lens, the parallel light beam formed by the primary lens can enter and exit according to changes in the light amount of the optical image. When the light transmittance of the optical filter that is controlled and has the maximum light transmittance is A, the light transmittance of the other optical filters is A.
An optical system that includes a plurality of optical filters having a relationship of ^2^^m (m is a positive integer) and an aperture that is arranged within a parallel beam of light and whose aperture diameter is varied according to photoelectric changes in an optical image. An X-ray television imaging device comprising: (2) The plurality of optical filters are controlled to be able to move in and out of the parallel light beam in response to a change in the light amount of an optical image due to switching of the operation mode of the X-ray television imaging device. X-ray television imaging equipment. (3) The X-ray television photographing apparatus according to claim 1, wherein the diaphragm and the optical filter operate in response to a change in the light amount of the optical image due to a change in the conversion coefficient of the image intensifier. (4) The iris according to claim 1, wherein the diaphragm finely adjusts the amount of light that passes through the primary lens, and the optical filter roughly adjusts the amount of light that passes through the primary lens. line television photography equipment.