JPH06121231A - X-ray diagnostic device - Google Patents

Abstract

PURPOSE:To improve the resolution by arranging a light receiving means such as a photo sensor at the outside of an optical path of a television camera so as to avoid interruption of an optical path. CONSTITUTION:A picture outputted from an output face 9 of an image intensifier I.I. is picked up by a TV camera optical system 12 via an optical path 5. Then a photosensor 11 is installed at an outside of the optical path 5 to measure a luminous quantity outputted from the output face 9 of the I.I. In this case, since the output face 9 of the image intensifier I.I. is almost a 100% complete diffusion face, the light outputted from the output face 9 is surely made incident in the photo sensor 11. That is, since no light shield is in existence in the optical path 5, the luminous quantity is not decreased and the resolution of an X-ray diagnostic picture is improved. Furthermore, a PMT (photo multiplier tube) or an optical semiconductor element or the like is used for the photo sensor 11 and especially a photo diode is small and effective.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an X-ray diagnostic apparatus, and more particularly to improvement of a lighting means for collecting output light of an image intensifier (II).

[0002]

2. Description of the Related Art Generally, in an X-ray diagnostic apparatus, an image intensifier (hereinafter referred to as I.
I. Is converted to an optical signal, and the I.D. I. The X-ray diagnostic image is obtained by imaging the output surface of the device with a TV camera. At this time, in order to determine the optimum X-ray exposure condition (
BC / AEC), I. I. The output light is collected and this optical signal is fed back.

FIG. 11 shows a conventional example of such an X-ray diagnostic apparatus. I. The output light emitted from I.I. I. An image is taken by the TV camera 4 through the lens 2 and the TV lens 3. In addition, I. I. A mirror 6 for collecting light is arranged on an optical path 5 between the TV camera 1 and the TV camera 4, and the collected light passes through a lens 7 and a photomultiplier tube 8 (hereinafter,
It is taken in by PMT) and supplied to the ABC circuit and the AEC circuit. Then, according to this, I. The brightness of the image No. 1 and the X-ray exposure condition are controlled.

[0004]

However, in such a conventional X-ray diagnostic apparatus, since the light-collecting mirror is arranged on the optical path 5, the amount of light collected by the TV camera 4 is reduced. Therefore, there are drawbacks that the resolution of the X-ray image is reduced and the image is vignetted. Also, since the position of the mirror 6 is constant, the I.D. I. There is a problem that it is not possible to select from which position on the first output surface the light is to be picked up, that is, multi-lighting cannot be performed.

The present invention has been made to solve such a conventional problem, and its purpose is to
An object of the present invention is to provide an X-ray diagnostic apparatus that can perform imaging without reducing the amount of light collected by the V-camera 4 and that is easy to multi-light.

[0006]

In order to achieve the above object, the present invention provides an image intensifier (II) for converting X-rays transmitted through a subject into an optical signal, and the image intensifier (II).
I. An optical system for capturing an image of the output surface with a TV camera;
I. Between the optical system and the optical system. I. In the X-ray diagnostic apparatus having at least a lighting means for collecting the output light of the above, the lighting means is arranged outside the optical path of the TV camera.

[0007]

With the above-mentioned structure, the light collecting means such as the photo sensor is arranged outside the optical path of the TV camera, so that the optical path is not blocked. Therefore, the amount of light taken into the TV camera does not decrease and the resolution of the X-ray diagnostic image is improved. Further, since it is possible to perform multiple lighting by using the photosensor, it is possible to perform accurate lighting according to the inspection site.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. 1 is a block diagram showing an image intensifier I.I. of the X-ray diagnostic apparatus according to the first embodiment of the present invention. I. Output side 9 and T
It is a block diagram which shows the part of the V camera optical system 12.

As shown in FIG. I. The image output from the output surface 9 passes through the optical path 5 and is captured by the TV camera optical system 12. And I. I. A photo sensor 11 is installed outside the optical path 5 to measure the amount of light output from the output surface 9. And according to such a configuration, the I.D.
I. Since the output surface 9 is a nearly 100% perfect diffusion surface, the light output from the output surface 9 is surely emitted from the photo sensor 11.
Will be incident on. In other words, since there is no object that blocks light in the optical path 5 as in the conventional case, the amount of light does not decrease and the resolution of the X-ray diagnostic image is improved. Moreover, since the mechanism can be configured with a simpler structure than the conventional one, the device can be simplified.

The photosensor 11 may be a PMT (photomultiplier tube) or an optical semiconductor device that is generally used. In particular, the photodiode is small and effective.

FIG. 3 is a block diagram showing a second embodiment of the present invention. As shown in the figure, in this example, a collimator 13 is attached to the light incident portion of the photo sensor 11. Collimator 13
Can be constituted by a slender cylindrical tube 14 as shown in FIG. 2 (b) as the simplest one.
As shown in FIG. This allows the photosensor 11 to have a visual field. That is, in the first embodiment shown in FIG. I. Light was collected from the entire output surface 9, but in the second embodiment of FIG. I. It is possible to collect light from only a specific portion of the output surface 9. At this time, the light-collecting field of the photosensor 11 is elliptical as shown by reference numeral 15 in FIG. 4, and the shape of the light-collecting field at this time is determined by the mounting angle of the photosensor 11 and the shape of the collimator 13. In addition, the inside of the collimator 13 needs to be non-reflective coating so as not to unnecessarily increase the lighting field.

FIG. 5 is a block diagram showing an example in which an optical fiber is used as the collimator 13. When an optical fiber is used, the maximum incident angle θ of the incident light is the NA of the fiber
Determined by the number. For example, when a general quartz fiber is used, the NA number is about 0.2, and θ = sin ⁻¹ (NA number) = 11 °
Therefore, it is possible to collect only the light entering from the optical path 5 shown in FIG.

FIG. 6 is a block diagram showing a third embodiment of the present invention. The figure (a) is a side view and the figure (b) is a view seen from above. As shown, three photosensors 11 are provided. Then, each photo sensor 11 is divided into three I.S. I. The amount of light from each part of the output surface 9 is collected and the signal S
1 to S3 are output to the ABC circuit and the AEC circuit.

According to such a configuration, the I.D. I. Since it is possible to arbitrarily select a portion on the output surface 9 for lighting, multiple lighting is possible. Further, the output signals S1 to S3 can be used independently or can be added in an analog manner and used as necessary. Especially if you add the two signals together,
It is equivalent to selecting two areas of the lighting field at the same time.

Although an example in which a photodiode is used as the photo sensor 11 is shown in FIG. 6, a PMT may be used. At this time, the space may be narrowed due to the multi-use, but there is a method in which an optical transmission component such as an optical fiber is installed at a position where the collimator 13 is originally installed and transmission is performed to a plurality of PMTs installed at different places. It is possible.

FIG. 7A is a configuration diagram when an optical fiber is used as the collimator 13. When the light is collected by such a configuration, as shown in FIG. I. The entire output surface 9 can be the lighting field 15. Then, the photo sensor array 17 as shown in FIG. 8 is attached to the other end of the optical fiber. As a result, the area where one channel of the photosensor array 17 collects light is 1 / N of the total number of the photosensor array 17. Then, for example, when lighting is performed in the region 16, a portion h determined by 1 / N and the NA number becomes a lighting field as shown in FIG.

Here, a photodiode array, a linear sensor, or the like can be considered as the photosensor array 17, but it is better to be able to output independently in consideration of signal processing. Also, even if the fiber end is divided into a predetermined width and the PMT is attached to each bundle, the same function can be obtained.

FIG. 10 is a block diagram showing a fourth embodiment of the present invention. As shown, in this example, the drive unit 18 is provided in the photo sensor 11. Then, the drive unit 18 can move the photosensor 11 in three-dimensional directions (vertical, horizontal, front-back), and by using this, it is possible to move the lighting field in accordance with the actual examination site.

[0019]

As described above, according to the present invention, a light collecting means such as a photo sensor is provided outside the optical path between the output surface of the image intensifier (II) and the optical system for imaging the output surface. Therefore, the light is not blocked and the resolution of the X-ray diagnostic image is not reduced. Further, since multi-lighting is easy, the resolution of light amount detection is improved. Furthermore, since a photo sensor is used to detect the amount of light,
The effect that the configuration is simplified is obtained.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a first embodiment of the present invention.

FIG. 2 is an explanatory diagram showing a photo sensor and a collimator.

FIG. 3 is a configuration diagram showing a second embodiment of the present invention.

FIG. 4 is an explanatory diagram showing a daylighting field when a collimator is used.

FIG. 5 is an explanatory diagram showing a lighting angle when an optical fiber is used as a collimator.

FIG. 6 is a configuration diagram showing a third embodiment of the present invention.

FIG. 7 is an explanatory diagram showing a collimator composed of an optical fiber and a lighting field thereof.

FIG. 8 is a configuration diagram showing a photo sensor array.

FIG. 9 is an explanatory diagram showing a daylighting field by a photosensor array.

FIG. 10 is a configuration diagram showing a fourth embodiment of the present invention.

FIG. 11 is a configuration diagram showing a conventional example.

[Explanation of symbols]

 1 image intensifier (II) 5 optical path 9 I.I. I. Output surface 11 Photo sensor 12 TV camera optical system 13 Collimator 15 Lighting field 17 Photo sensor array 18 Driving unit

Claims (1)

[Claims] 1. An image intensifier (II) for converting X-rays transmitted through an object into an optical signal, and the I.I.
I. An optical system for capturing an image of the output surface with a TV camera;
I. Between the optical system and the optical system. I. An X-ray diagnostic apparatus having at least a daylighting means for collecting the output light of the above, wherein the daylighting means is arranged outside the optical path of the TV camera.