JPH06285055A - X-ray photographing device - Google Patents

Abstract

PURPOSE:To dispense with adjusting and setting a reference value by using a value obtained by the previous operation, that is, an integral value of an output of a photodetector for detecting partial light of an optical image obtained by an image intensifier, as a reference value of X-ray control. CONSTITUTION:In one area of an optical image formed by an image intensifier 13, a photodetector 12 for detecting the quantity of light in this area is arranged, and its output is inputted to an integration circuit 11. Subsequently, an output of the integration circuit 11 is inputted to an automatic exposure device 7, compared with a reference value determined in advance by a comparing circuit 8, and at the time point when it becomes the reference value, a signal of its fact is outputted to an X-ray controller 2. As a result, X-ray irradiation by an X-ray tube ball 1 is cut off by an X-ray cutting-off circuit 6. Also, the output of the integration circuit 11 is stored each time in a memory circuit 10 through a reference value input/output circuit 9, and used as the reference value of the comparing circuit 8. In such a way, automatic proper exposure can be attained without taking a useless time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray imaging apparatus,
In particular, it relates to an X-ray imaging apparatus including an X-ray control device.

[0002]

2. Description of the Related Art An X-ray imaging apparatus having so-called automatic exposure irradiates X-rays with a preset imaging tube voltage and imaging current, and an X-ray image obtained through a subject is converted by an image intensifier. A signal corresponding to the light amount of the light image is detected, and the X-ray irradiation is blocked when the integrated value of the signal reaches a value (reference value) corresponding to an appropriate film density.

The reference value must be adjusted and set in advance based on the type of film or intensifying screen or the sensitivity of the image intensifier.

That is, X is changed while gradually changing the reference value.
The work involved irradiating a line and determining by film development whether or not the film had an appropriate film density.

[0005]

However, the X-ray imaging apparatus constructed as described above must set an appropriate reference value while performing the above-mentioned work. Therefore, until the set reference value is obtained. There was a problem that it took more time than necessary.

Therefore, the present invention has been made based on such a circumstance, and the object of the present invention is to eliminate the need to adjust and set the set reference value, thus wasting time. An object of the present invention is to provide an X-ray imaging apparatus capable of achieving proper automatic exposure without any need.

[0007]

In order to achieve such an object, the present invention basically provides an X-ray tube and an X-ray tube.
An image intensifier for inputting X-rays from a tube from the subject, a light receiving element for detecting at least a part of light of an optical image obtained by the image intensifier, and an output of the light receiving element. In an X-ray imaging apparatus including an X-ray controller that controls the X-ray tube based on a comparison of an integral value with a preset value, a storage device that stores an integral value of the output from the light receiving element. And means for using the integrated value stored in the storage device as the set value.

[0008]

The X-ray radiographing apparatus constructed in this manner uses the value obtained by the previous operation, that is, the integrated value of the output from the light receiving element, as the reference value for X-ray control.

This is recalled because the setting of tube voltage and tube current only sets mAs in the autoexposure device after all.

To this end, in particular, it is provided with a storage device for storing the integrated value of the output from the light receiving element, and means for replacing the integrated value stored in the storage device with a set value set by conventional input. It was done like this.

Therefore, it is no longer necessary to adjust and set the set value as in the conventional case, and proper automatic exposure can be achieved without wasting time.

[0012]

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

In FIG. 1, there is an X-ray tube 1 first. The X-ray tube 1 is controlled by an X-ray controller 2 and is irradiated with X-rays based on the tube voltage and the tube current by the tube voltage setting circuit 3 and the tube current setting circuit 4 in the X-ray controller 2. It has become so.

The X-rays from the X-ray tube 1 are input to the image intensifier 13 as X-ray images transmitted through the subject 14. The image intensifier 12 converts the input X-ray image into a light image, and the light image is input into a television camera (not shown) and converted into an electric signal. The optical image is monitored based on the signal.

The monitor via the television camera is usually used in the perspective stage, and the film (not shown) is irradiated with X-rays during the photographing.

A light receiving element 12 for detecting the amount of light in this area is arranged in one area of the optical image formed by the image intensifier 13, and its output is input to the integrating circuit 11. That is, the integration circuit 11 outputs a signal corresponding to the amount of X-rays irradiated with the passage of time, and thus a signal corresponding to the development density of the film.

The output from the integrating circuit 11 is input to the automatic exposure device 7. A comparison circuit 8 is incorporated in the automatic exposure device 7, and the comparison circuit compares the output from the integration circuit 11 with a predetermined reference value, which is equal to the reference value. When that happens, a signal to that effect is output to the X-ray controller 2.

The reference value is input by an operator, for example, via the input circuit 9, and is a value determined by inputting set values of tube voltage and tube current.

In the X-ray controller 2, when the output is input, the X-ray cutoff circuit 6 is driven, whereby the X-ray irradiation by the X-ray tube 1 is cut off.

On the other hand, in this embodiment, the output from the integrating circuit 11 is stored in the memory circuit 10 via the reference value input / output circuit 9 each time, and further, the output thus stored. Is the automatic exposure device 7 as a reference value.
It is designed to be used as a reference value for the internal comparison circuit.

That is, the information (tube voltage and tube current) corresponding to the reference value can be input through the input / output circuit 7, and the reference value previously stored in the memory circuit 10 can also be input. ing.

In the X-ray imaging apparatus constructed as in the above embodiment, the value obtained by the previous operation as the reference value for the X-ray control, that is, the output from the light receiving element 12 is passed through the integrating circuit 11. The integrated value is used.

This is recalled because the setting of tube voltage and tube current only sets mAs in the automatic exposure device.

For this purpose, in particular, the memory circuit 10 for storing the integrated value of the output from the light receiving element 12, and the means for replacing the integrated value stored in the memory circuit 10 with the set value set by the conventional input. It is equipped with and.

Therefore, it is no longer necessary to adjust and set the set values as in the conventional case, and proper automatic exposure can be achieved without wasting time.

[0026]

As is apparent from the above description,
According to the X-ray imaging apparatus of the present invention, it is not necessary to adjust and set the setting value as in the conventional case, and proper automatic exposure can be achieved without wasting time.

[Brief description of drawings]

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 X-ray tube 10 Memory circuit 11 Integration circuit 12 Light receiving element 13 Image intensifier 17 Automatic exposure device

Claims (1)

[Claims] 1. An X-ray tube and an image intensifier for inputting X-rays from the X-ray tube through a subject.
The X-ray tube based on a comparison between a light receiving element that detects at least a part of the light of an optical image obtained by the image intensifier and a preset set value of the integrated value of the output from the light receiving element. In an X-ray imaging apparatus including an X-ray control device for controlling, a storage device that stores an integrated value of an output from the light receiving element, and a unit that uses the integrated value stored in the storage device as the set value. An X-ray imaging apparatus characterized by being provided.