JPS59221093A - X-ray picture input device - Google Patents

Abstract

PURPOSE:To obtain continuously X-ray pictures from an X-ray TV signal for monitoring by controlling the read-out of electric charge on an image pickup tube from outside synchronously with the X-ray exposure, and storing the X-ray pictures to a memory based the read-out electric charge. CONSTITUTION:A timing control part 41 within a picture display input control part 31 starts reading out the electric charge from a time point when the generation is through with the pulse X rays and outputs the shift pulse to an X- ray TV camera 30. The signal S6 read out of the cameral 30 is stored to a memory part 43 after an A/D conversion 42. While the part 41 outputs a vertical/ horizontal scan signal S8 to an X-ray TV monitor 9 and simultaneously reads out the picture data stored in the part 43 synchronously with the field operation of the monitor 9 to transmit it to the monitor 9. If the number of times of generation of pulse X rays per second is larger than the number of fields of the monitor 9, thinning-out is displayed. While a multiplex display is executed if said generating frequency is smaller than said number of fields.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an image input device that continuously obtains X-ray images from an X-ray television signal of an X-ray television system for a monitor equipped with an Xa cine shadow device. It is.

[Technical background of the invention]

As a direct method for evaluating cardiac function, cardiac angiography images are taken continuously on cine film, and after development, the images are played back and displayed as a movie, the movement of the images is observed, and if necessary, cardiac A widely used method is to manually measure and analyze various feature quantities for quantitatively evaluating functions.

However, with this method, the image must be observed after the film is developed, and manual measurement is required.
The drawback is that it takes a considerable amount of time and effort to produce analysis results.

Currently used X#! One way to solve the above problem using a cine imaging device is to use an X-ray TV signal 4 simultaneously output from an One example is a method in which an X-ray contrast image converted into a television signal is converted into digital data and then input into a computer system for analysis.

However, with X-ray cine imaging equipment, in order to reduce the X-ray exposure dose to the subject, when shooting cine film, Xi is generated intermittently in synchronization with the frame advance of the cine camera. The number of frames per unit time of a cine camera and the number of fields per unit time of an X-ray television system are generally different and are not synchronized. Therefore, the reality is that even if image data is simply input from an X-ray television signal, it is difficult to obtain an image that meets the purpose.

Here, FIG. 1 shows the configuration of a conventional X-ray cine imaging apparatus. In the figure, reference numeral 1 indicates an X-ray controller 5 which performs settings such as X-ray tube current and tube voltage, and X-ray exposure control, and reference numeral 2 indicates an output X-ray generation signal 8 from the X-win controller 1. Xtij is a high voltage generator that generates a high voltage corresponding to the setting conditions of the controller 1 in a pulsed manner in synchronization with the frame advance of the cine camera 7. For synchronization with the cine camera 7, the shutter synchronization output of the cine camera 7 is used. Reference numeral 6 denotes an X-ray tube that receives the high-voltage output of the high-voltage generator 2 and irradiates X-rays, 4 is the object, and 5 is provided facing the X-ray tube B through the object 4, and An image intensifier (hereinafter referred to as 1.1.) 11, which converts the image into a line optical image and outputs it, guides the output image of L1, 5 to the X-ray television camera 8 (it is a lens of an optical system). A half mirror 6 is provided between the optical system lens 11 and the X-ray television camera 8 to divide the guided optical image into two.
．． The output image of 1.5 is also guided to the cine camera 7. Reference numeral 9 denotes an X-ray television monitor that receives a video signal obtained by imaging by the X-ray television camera 8 and displays it as an X-ray television signal, and 10 records the video of the X-ray television camera 8. It is a video tape recorder.

In such a configuration, Xizi TV has cine camera 7
It is provided for monitoring photography. When performing X-ray cine photography, the X,1 controller 1 is activated and the X-ray controller 1 is placed in a standby state for the start of X-ray exposure. Then, when the signal S14 is manually applied to the cine camera 7, the cine camera 7 operates and a signal S2 indicating that the cine camera shutter is opened is output, and in synchronization with this, an X-ray exposure signal S3 is output from the X-ray controller 1. As a result, high voltage is supplied from the high voltage generator 2 to the X-ray tube 6 for the set time width, and this X-ray tube 6
Pulsed X-rays are generated in synchronization with the cine camera 7.

This pulsed X-ray passes through the subject 4 and 1. I.

The X-ray image is incident on the input surface of 5, is amplified and converted into an optical image, and the X-ray image of the subject 4 is output as an optical image on the output surface of 1.1.5. This optical image passes through a lens 11 and is distributed by a half mirror 6 to a cine camera 7 and an X-ray television camera 8. Then, the cine camera 7 captures the image on a cine film, and the X-ray television camera 8 captures the image as a television image, which is displayed on the X-ray television monitor 9 .

Also, if necessary, it is recorded on the video tape recorder 1o.

Since the purpose is cine photography, the operation of generating X-rays and the operation of photographing cine film are completely linked here, but the X# TV system operates independently of these operations. In other words, the number of frames per unit time for cine film and the number of fields per unit time for television are different, and since the purpose is to shoot cine film, they are synchronized for cine film shooting. , Therefore, synchronization with the television system has not been achieved.

As a result, 1. For example, if the number of fields per unit time of the television system is greater than the number of frames of the cine, the period of the vertical beam set in the X-ray television system will be shorter than the period of generating X-rays, and this In this case, the beam scanning in the vertical direction at the target, which is the imaging surface of the image pickup tube of the XM television camera 8, will be performed for more than one cycle for - times of X-ray generation, so only the afterimage will be output. This results in a portion where the level of the interposed signal drops significantly.

In other words, when the image pickup tube forms an optical image, a charge image corresponding to the sight of the optical image is generated on the target, so by field scanning the target with an electron beam, a current corresponding to the amount of charge in the charge image is generated as a video signal. obtained as. Therefore, when the target is scanned by 1) the yield, the charge image disappears, so no video signal can be obtained until the next optical image is formed. In reality, even after one field scan with an electron beam, there is an afterimage, so in the next field scan, the afterimage will be obtained as a signal, but the level will be extremely low. Therefore, when the -th field scan is completed and the second and subsequent field scans are being performed,
When the X-rays are exposed, a phenomenon occurs in which the video signal level increases from the scanning position at the stage where the X-rays were exposed.

In addition, if you use an image pickup tube with almost no afterimage, there will be almost no image after the first field scan is completed until X-ray exposure is completed, and in this case, there will be a black image in the horizontal direction. An image mixed with band-like patterns will be output.

This will be explained in detail using FIGS. 2 and 6. Figure 2 (a
l indicates the timing of generating Xi, and FIG. 2(b) shows the timing of the vertical synchronizing signal to represent the vertical scanning 2 of the X-ray television system.

Figure 2 (
When X-rays are generated and photographed using an X-ray television camera as shown in a), first, in field F1 in the figure, X-rays P
Since the charge images accumulated on the image pickup tube due to the occurrence of 1 are simply read out sequentially, a normal image output can be obtained from the X-ray television camera, and there is no problem.

However, in field F2, reading out the charge image of the image pickup tube starts before the next X-ray P,2 is generated, so X? Since the charge image on the image pickup tube has already been read out until fM P 2 occurs, the output video signal is only the afterimage.

When XdP2 is generated, charges are accumulated on the image pickup tube again, so that the output level of the video signal returns to normal during field scanning. Therefore, the field F of Xi TV thread
2, the image is as shown in Figure 2 (C), and the X-ray P2
The output level decreases in the shaded area, which is the scanning area until the occurrence of the phenomenon.

Similarly, the output in field F3 corresponds to the area where beam scanning has already been completed before the generation of X-rays 220 in field F2, and the beam scanning area after generation of X-rays P2. In the region of m1, the charge image remains intact. Therefore,
In field F3, a normal level of video output is obtained when this area is scanned, but when the latter area is scanned, the level drops because only the afterimage remains.

Since X-rays P3 are generated during scanning in this area, the level of the image output recovers from that point on.6 As a result, the image in field F3 becomes as shown in Figure 2(d). Become.

Because the generation cycle of X-rays and the field scanning cycle of the The processing content in the process of analyzing becomes complicated.

[Purpose of the invention]

The present invention was made in view of the above circumstances, and the present invention
To provide an image input device that can continuously input complete X-ray images using the video output of an X-ray television system for a monitor without making any changes to the basic structure of the g-cine imaging device. The purpose is to

[Summary of the invention]

X White according to this invention to achieve the above object! The outline of the image input device consists of a television camera that can externally control the readout of the charge on the imaging tube based on the X-ray image taken for each X-ray exposure, and a television camera that can control the readout of the charge from the outside. The apparatus is characterized by having a control means that performs the operation in synchronization with the time of radiation, and a storage means that inputs an X-ray image based on the read charges.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 6 is a block diagram of the X-ray image input device, FIG. 4 is a schematic explanatory diagram of the X-ray television camera, and FIG. 5 is a block diagram of the image input/display control section.

In FIG. 6, X-ray controller 1. High voltage generator 2 and X
The i-TV monitor 9 has the same functions as the members shown in FIG. 1 with the same reference numerals. The Xa1 television camera 0 uses a solid-state photographing element whose readout timing of the charge image S6 based on optical image formation can be controlled from the outside. The image input/display control section 1 generates a charge readout signal S5 based on the pulsed X-ray generation signal S6, and inputs a charge image S6 from the X-ray television camera O based on this. The image input/display control unit 61 also controls the X-ray exposure
The image 87 taken at
For the line television monitor 9, the lI! selected along with the horizontal direct scan signal S8! ii image 89 is output. The disk 2 stores the input image S7, and the output image SIQ is inputted to the image analysis section 3B as required.

Next, details of the X-ray television camera 30 will be explained with reference to FIG. 4. FIG. 4 is a schematic explanatory diagram of an interline type CCD area image sensor as an example of the X-ray television camera 60.

In FIG. 4, 51 is a photodiode which performs photoelectric conversion using incident light for a predetermined period of time and accumulates charges. 52
is an electrode, which transfers the charges all at once to the vertical CCD register 5.
A voltage (shift pulse) for shifting is applied to the photodiode 51. The photodiode 51
The vertical CCD registers 56 are arranged in a plurality of columns corresponding to the vertical and horizontal directions of the image. The charges in the vertical CCD register 56 are transferred in parallel to the horizontal register 54 by -horizontal, and the charges transferred to the horizontal CCD register 54 are sequentially transferred to the output section 55. Also,
Terminal P1 is a shift pulse φ for transferring the charge accumulated in the photodiode 51 to the vertical CCD register 5B.
This is the terminal for inputting F.

Terminals P2 to P5 are terminals into which control signals φV to φ■4 are input for transferring charges in the vertical CCU register 56 in parallel to the horizontal CCD register 54 one horizontal line at a time. Terminal P6. P7 is the horizontal CCI) register 54
A control signal φ for sequentially transferring the charges in the output section 55
This is a terminal for inputting H1 and φH2.

Next, the image input/display control section 61 will be explained in detail with reference to FIG. In FIG. 5, the image input and
The display control unit 1 includes an A/D converter for A/D converting an analog signal 86 which is a charge image output from the X-ray television camera 60.
/D converter 42, a timing control unit 41 which is a control means that determines the timing of image display, and a digital image S12 which is the output of the A/D converter 42. : It consists of a memory section 4 which is a storage means for storing data, and a D/A converting section 44 which inputs the digital image 813 read from the memory section 46 and converts it into analog.

The timing control unit 41 outputs the charge readout signal S5 based on the pulsed X-ray generation signal S6 and the A/D.
A signal 814 for operating the converter 42, a horizontal/vertical scanning signal S8 outputted to the X-ray television monitor 10, and an image of - from the memory section 46 marked ω■ in synchronization with the horizontal/vertical scanning signal S8. An image readout signal 811 for reading out the image is generated. The image readout symbol S11 is designed to select the last image stored in the memory section 4 to be read out in synchronization with the horizontal and vertical scanning signals S8.

The memory section 46 includes first to fourth memories 43a to 43d. Each of these memories 43a to 4
3d is configured to input and store images sequentially output from the A/D converter 42.

The operation of the X-ray image input device configured as described above will be explained with reference to the timing charts of FIGS. 6 and 7.

First, the operation of reading out the charge image S6 from the X-ray television camera 60 will be explained with reference to FIG. Figure 6 (a
) to (f) are charge images S6 from the X-ray television camera 60.
3 is a timing chart for explaining a read operation.

FIG. 6(a) shows the pulsed X-ray generation signal S6, at which pulsed X-rays are generated and an X-ray image is taken. The timing control unit 41 starts reading out the charge from the time when the generation of pulsed X-rays ends, and first generates a shift pulse φF shown in FIG. Output.

Based on this shift pulse φF, the photodiode 5
Reading of the charges accumulated in 1 is started. Then, charge transfer is performed within a certain period (see FIG. 6(C)) after the shift pulse φF. Note that the cine shooting speed of the cine camera 7 shown in FIG. 1 is variable.

The charge readout speed is set according to the maximum cine shooting speed. Within the period shown in Figure 6(C) above (
During the charge transfer period), the -horizontal charge is transferred to the vertical CC
The period during which data is transferred from the D register 56 to the horizontal CCD register 54 (see FIG. 6(d)) and the period during which the data is transferred from the horizontal COD register 54
The period in which the charges in the image are transferred and read out one pixel at a time (Fig. 6 (
(see e) is repeated. Then, the timing control unit 41 transmits a charge readout signal S5 based on the standard of the solid-state device of the X-ray television camera 60 to the X-ray television camera 60.
0, and the charge image S8 is read out (sixth
(See figure (f)).

The charge image S8 read out in synchronization with the pulsed X-ray generation signal S6 is A/D converted by the A/D converter 42 and sequentially stored in the memory section 46.

The images in the memory section 46 are then transferred to the disk 62 and subjected to image analysis in an image analysis section 63 as needed.

Next, image display control on the X@television monitor 9 will be explained with reference to FIG. In this invention, since the control of the Xi television camera 8 is performed in synchronization with the generation timing of pulsed X-rays, reading out the electric charge of the X-ray television camera 8 and field scanning of the X-ray television monitor 9 are performed independently. It will be.

Therefore, when displaying an X-ray image on the X-ray television monitor 9, one frame of the image to be displayed is selected for each field, and stable image display is achieved by thinning out or overlapping display.

These 7riIt+a are performed by the timing control section 41. The timing control section 41 generates a vertical/horizontal scanning signal S8' that restricts the beam scanning of the monitor system and outputs it to the X-ray television monitor 9.
The image data 813 stored in the D/A converter 4 is read out in synchronization with the field operation of the X-ray television monitor 9.
4 to convert to analog signal S9 and send it to Xal TV monitor 9
Output to. Here, the image to display in each field is
It is assumed that among the images that have already been stored in the memory unit 4 at the time of generation of the vertical scanning signal, the storage is completed last. As a result, if the number of pulses Xi generated per second is greater than the number of fields on the X-ray television monitor 9, thinning display is performed, and in the opposite case, overlapping display is performed. An example of stiffness will be explained with reference to FIGS. 7(a) to (e).

Is Fig. 7(a) the generation timing of the vertical scanning signal? It shows. On the other hand, if the X-ray image shown in FIG. 7(b) is collected because the pulse XH is generated early, the vertical scanning signal (
7th &: (a) At the time of occurrence, the memory unit 46 is already
The last of the images that have been completely stored in is output and a thinned-out display is performed. On the other hand, if the pulsed X-ray generation timing is later than the vertical scanning signal generation timing, an X-ray image shown in FIG. 7(d) is acquired. In this case, as shown in FIG. 7(e), overlapping display will be performed according to the same operation as described above.

Note that the operation of reading data to be transferred from the memory unit 46 to the disk 62 and the operation of reading data to be displayed on the X-ray television monitor 9 can easily be performed in one time division process. Furthermore, the image data to be displayed on the X-ray television monitor 9 must always be stored in the memory section 46. Is this memory if the cine shooting speed is fast? A4
This is because the image data stored in the X+tJ television monitor 9 may be rewritten faster than the field scanning speed of the X+tJ television monitor 9. Therefore, the memory section 43
requires a plurality of image memories, and even if the cine imaging speed is high, it is necessary to store the image data being displayed on the X-ray television monitor 9.

〔Effect of the invention〕

As described above, according to the present invention, it is possible to provide an X-ray image input device capable of inputting an X-ray image based on pulsed X-rays generated for cine imaging as a complete image. Therefore, compared to an image input method using an Xs television signal of a conventional X-ray imaging apparatus, it is possible to input images with uniform output levels that are easy to analyze. In addition, the present invention can be implemented by simply changing the X-ray television camera of the X-ray imaging device, and most of the existing equipment can be used as is.

[Brief explanation of drawings]

Figure 1 is a block diagram of a conventional X-ray cine imaging device, and Figures 2 (a) to Atsushige\(d) are the generation timing of pulsed X-rays, the field scanning timing of the X-ray television system, and the television during cine imaging. 6 is a block diagram of the XfaJ image development input device according to the present invention; FIG. 4 is a schematic explanatory diagram of an interline type CCU area image sensor as an example of the XfaJ television camera; FIG. 5 is a block diagram of the image input/display control unit, FIGS. 6(a) to (f) are timing charts for explaining the operation of reading out a charge image from an X-ray television camera, and FIG. 7(a) -(e) are timing charts for explaining image display control on an X-ray television monitor. 9...Display unit (X-ray television monitor), 60...
X-ray television camera, 41...control means (timing control section), 4ro...storage means (memory fA). Representative Patent Attorney Kensuke Nori Chika (and 1 other person) Condolences 1

Claims (1)

[Scope of Claims] (A television camera capable of externally controlling the readout of electric charge on a photographing tube based on an X-ray image taken every time 11Xi is exposed; and An Xa image input device characterized by having a control means that performs synchronization, and a storage means that inputs an X-ray image based on the read charge. (2) The control means is arranged perpendicularly to the display section. , outputting a horizontal scanning signal and synchronizing with the vertical scanning signal,
The X-ray image according to claim 1, wherein the X-ray image that has been stored last among the X-ray images that have been completely stored in the storage means is read out and controlled to be output to the display section. Input device.