JPS62122488A - X-ray machine - Google Patents

Abstract

PURPOSE:To improve the quality of a picture by arranging a television system and an automatic control system respectively on a different optical path separated by a luminous quantity distributing member to prevent vignetting by a luminous quantity detector in an angle type optical system from being caused. CONSTITUTION:Light from a light image on an output fluorescent screen I.I5 is made incident on an I.I lens 6a, where the light is collimated and the parallel ray is divided into an optical path reflected in a direction of a TV camera 7 by a half mirror 6f and an optical path going straightfoward through the half mirror 6f as it is. The light going straightforward through the half mirror 6f is made incident on the luminous quantity detector 6c, and converted to an electric signal by a photomultiplier 6c6 and sent to a controller 9 as a detection signal to control the X-ray exposure condition automatically. The light from the screen I.I is reflected by the half mirror in this way and since no hindrance exists on the path until it is made incident on the TV camera, no vignetting due to the luminous quantity is caused and the image sent to the TV camera is brought into high quality.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an imaging device that performs X-ray photography by controlling the exposure conditions of X-rays emitted from an X-ray tube, such as a medical X-ray device. is.

[Technical background of the invention and its problems] A conventional medical X-ray apparatus is shown in FIGS. 4 to 7.

Fig. 4 is a schematic diagram of a medical X-ray device combined with an overtube table type X-ray TV bed, Fig. 5 is a block diagram of a conventional medical X-ray device, and Fig. 6 is a diagram of a conventional medical A structural diagram of the optical system, and FIG. 7 is a schematic diagram of the m-detector. In the figure, 1 is an X-ray tube, 2 is an X-ray diaphragm, 3 is a subject (patient), 4 is a bed, 5 is an image intensifier (hereinafter referred to as I-I), 6 is an optical system consisting of a light intensity detector 6C, etc. system, 7 is a TV camera, 8 is a TV monitor, 9 is a control device that adjusts the amount of X-ray exposure, 10 is an
This is a high pressure generator that supplies high pressure to be applied to the wire tube.

The automatic exposure control and automatic brightness control of X-rays in conventional medical X-ray equipment configured as described above are
After the line is converted into an optical image by 1-15, the light from the optical image is detected by a light quantity detector 6G, and the X-ray exposure (2) is adjusted based on the electrical signal obtained by photoelectrically converting this.

In this case, in the conventional medical X-ray apparatus shown in FIG. 4, the I/I 5, optical system 6, and TV camera 7 must be placed between the subject 3 and the floor FL due to its mechanical structure. In addition, since the medical X-ray device is used in conjunction with a stretch V- (not shown) for moving a bedridden patient and another medical machine, such as an endoscope device, ergonomically, there is a gap between the subject 3 and the floor FL. The distance is inevitably fixed at a certain value. For this reason, TV camera 7 is installed! If it is placed opposite to the jl pipe 1, it will interfere with the floor FL. To prevent this interference,
The camera 7 is mounted in a direction bent by 90 degrees with respect to the X-ray irradiation direction (in the direction of the head of the subject 3 in FIG. 4). Due to these circumstances, the conventional medical XPi! The apparatus uses a tandem lens optical system shown in FIG.

Here, the tandem lens system is a well-known technology in the optical field, in which lenses are arranged so that the light rays between two sets of lenses become parallel rays.
! As shown in FIG. 6, the tandem lens type optical system 6 in the apparatus includes a mirror 6b, a light amount detector 5c, and a light amount detector 5c within a tandem interval that forms a parallel beam of light between an I-lens (objective lens) 6a and a TV lens 6e. A lens aperture 6d and the like are arranged to detect, adjust, and distribute the amount of light into two parts.

Note that 5a is the output phosphor screen of I-1, and 7a is the face plate of the tube. In addition, the light amount detector 6G is the seventh
As shown in the figure, the lighting field lens 6C1 and the prism 6C
2, a filter 6C3, a field diaphragm 6C4, a condenser lens 6Cs, and a photomultiplier 6Ca. The direction of the scene incident on the light field lens 6Ct is changed by a prism 602, the light amount is adjusted by a filter 603, and an image is formed on the field diaphragm 6C4 surface. The field stop 6C4 allows only the necessary amount of light to enter the condenser lens 6C5. The amount of light converged here enters the 7 otomaru 6C6 and is converted into an electrical signal.

By the way, the optical system (hereinafter referred to as an angle type optical system) in which the TV camera 7 is bent 90 degrees with respect to the X-ray irradiation direction as described above includes the T- and I lenses 6a and the TV lens 6.
mirror 6 between the tandem spacing that creates parallel rays between e and
b. A light amount detector 6c and a lens aperture 6d must be provided. This tandem interval becomes long because the mirror 6b is used, and the number of apertures of the lens is likely to occur. To prevent this, F1a of the I-I lens 6a should be made small (
The aperture of the lens must be increased (larger), making lens manufacturing difficult (if the focal length of the lens is the same, F
If the value is small, the curvature of the lens increases, making it difficult to correct lens aberrations.) If optical glass with a large refractive index is used to facilitate lens production, it has the disadvantage that it becomes expensive.

In addition, a light amount detector 6C for automatically controlling the tube voltage, tube current, and imaging time required under the X-ray exposure conditions during fluoroscopy and imaging is
Since the insertion position is determined by the lighting field, in order to remove it from the observation range on the TV monitor 8, the F number must be reduced, or in other words, the aperture of the lens must be increased.

For this reason, there are disadvantages in that the lens becomes expensive, the lens becomes large, and the device itself becomes large.

Furthermore, the light intensity detector 6G for automatically controlling the X-ray exposure conditions must be placed at a fixed position due to the lighting field.
You have to pull it. As a result, vignetting (a phenomenon in which the average light intensity within a certain range is partially damaged) occurs in the light intensity detector 6C, and a portion of the image on the TV monitor 8 is missing, resulting in an image with poor image quality and reliability. The disadvantage was that it resulted in a low value.

[Object of the Invention] The present invention has been made in view of the above circumstances, and provides an X-ray imaging device that can improve image quality by preventing the occurrence of vignetting caused by a light amount detector in an angled optical system. The purpose is to provide

Summary of the Invention 1 The summary of the present invention for achieving the above object is to convert an image of a subject by X-rays emitted from an In an X-ray imaging apparatus having a television system that displays on a monitor and an automatic control system that detects the light m of the optical image with a light amount detector and controls the @sword condition of the X-ray, the light amount of the optical image is A light amount distribution member is provided that distributes the light into a plurality of optical paths,
The television system and the automatic control system are arranged on different optical paths separated by the optical fiber distribution member.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. FIG. 1 shows the first embodiment of the present invention.
FIG. 2 is a schematic enlarged view of the optical system of the X-ray apparatus, and FIG. 3 is a schematic enlarged view of the optical system of the medical X-ray apparatus according to the second embodiment of the present invention.

Components having the same functions as those of the conventional medical X-ray apparatus shown in FIGS. 4 to 7 will be denoted by the same reference numerals, and detailed explanation thereof will be omitted.

In the figure, 6f is a half mirror, which has the property of reflecting half of the amount of incident light and transmitting the other half. This half mirror 6f is provided at an angle of 45 degrees with respect to the parallel light beam of the tandem lens type optical system. and,
A TV camera 7 is placed on the optical path reflected by the half mirror 6f, and a light amount detector 6C is placed on the optical path transmitted through the half mirror 6f.

Next, the operation of the present invention will be described. X-rays emitted from the X-ray tube 1 pass through the subject 3 via the X-ray diaphragm 2,
It reaches l-l5. The image formed by this X-ray is l-l
5, it is converted into an optical image and simultaneously amplified. Then, the optical image output from the output phosphor screen 5a of the l-l5 is reduced by two sets of lenses, the I-I lens 6a and the TV lens 6e of the optical system 6, and transmitted to the TV camera 7.
Observe and diagnose. At this time, as shown in FIG. 2, the light from the light image on the output phosphor screen 5a of I-15 is
It enters the lens 6a and becomes a parallel ray, and the half mirror 6
The light path is divided into an optical path that is reflected toward the TV camera 7 by f, and an optical path that passes straight through the half mirror 6f. The light beam distributed in the direction of the TV camera 7 is adjusted in light intensity by the lens diaphragm 6e, and enters the TV lens 6e n=+t, and enters the 7 eighth plays 1 to 7a of the IM picture tube built in the TV camera 7. form an image on top.

On the other hand, the light m that has passed through the half mirror 6f and gone straight is incident on the photodetector 6c and then converted into an electrical signal by the photomultiplier 60B, which is then used as a detection signal for automatically controlling the X-ray exposure conditions in the control device. Sent to 9.

According to the first embodiment of the present invention, the light from ■ and ■ is reflected by the half mirror and there are no obstacles on the path until it enters the TV camera, so Unlike photographing devices, vignetting due to the light amount detector does not occur, and the image transmitted to the TV camera can be of high quality.

In addition, since the optical path that passes through a half mirror separate from the optical path in which the TV camera is placed, there is no need to consider the occurrence of vignetting on the TV monitor due to the light amount detector, and the light amount Freely select the insertion position of the detector7
At the same time, there is no need to prevent the occurrence of vignetting due to the light intensity detector, so the I-I lens can be
You can choose the one with the highest value or lowest price.

Therefore, according to this embodiment, an inexpensive X-ray imaging apparatus can be provided.

Furthermore, since the light amount detector is located behind the half mirror, there is no problem of interference between the light amount detector and the half mirror, and the half mirror can be placed close to the I-luns side. As a result, the tandem distance between the ■/■ lens and the TV lens becomes shorter, making it possible to downsize the spectroscopic system.

Next, a second embodiment of the present invention will be described with reference to FIG. The half mirror 6fl is provided at an angle of 45 degrees with respect to the light from the optical image of l-l5 (which becomes a parallel beam of light due to the tandem lens type optical system). A TV is placed on the first optical path A1 reflected by the half mirror 6fz.
This is where the camera is placed. On the other hand, a mirror 6q is placed on the second optical path A2 where the light from the optical image passes through the half mirror 6fx.
is arranged perpendicularly to the optical path, and the reflected light from the mirror 6g is reflected again by the half mirror 6ft.
A second half mirror 6f2 is disposed on the third optical path A3 in the opposite direction to the optical path.

Then, a light amount detector 6G is arranged on the fourth optical path reflected by the second half mirror 6f2, and further,
The fifth optical path A transmitted through the second half mirror 6f2
5, an indirect camera lens 11 and an X-ray film 12 are provided for recording the optical image on film. The other configurations are the same as those of the first embodiment.

According to the second embodiment with the above configuration, since the light amount detector is disposed on a different optical path from the indirect camera, it is possible to obtain an X-ray photograph without vignetting due to light amount detection. Other functions and effects are similar to those of the first embodiment.

Note that the present invention is not limited to the above embodiments, and various modifications can be made within the scope of the gist of the invention. For example, by using a combination of a half mirror and a mirror, an indirect camera or a light amount detector can be placed at an arbitrary position.

[Effects of the Invention] As explained above, according to the present invention, the light amount detector and the TV
By placing the camera on a different optical path 2F, it is possible to provide an X-ray imaging device that can prevent the occurrence of vignetting due to the light amount detector attached to the angled optical system and improve the image quality. .

[Brief explanation of drawings]

FIG. 1 is a block diagram of a medical X-ray apparatus according to a first embodiment of the present invention, FIG. 2 is a schematic enlarged view of its optical system, and FIG. 3 is a medical X-ray apparatus according to a second embodiment of the present invention. FIG. 4 is a schematic enlarged view of the optical system of the X-ray device; FIG. 4 is a schematic diagram of a medical X-ray device combined with an overtube table type X-ray TV bed; FIG. FIG. 6 is a structural diagram of an optical system in a conventional medical X-ray apparatus, and FIG. 7 is a schematic diagram of its light amount detector. 1... X-ray tube, 2... X-ray aperture, 5... Image intensifier (I-I) 6.
...Optical system, 6f...Half mirror-16g...Mirror, 7...TV camera. Agent Patent Attorney Nori Chika Same as 1
Ogo Qufu l2 Funeral Figure 3 Figure 4 5 PJs Figure

Claims (3)

[Claims] (1) A television system that converts the image of a subject by X-rays emitted from an X-ray tube into an optical image, photographs this optical image with a television camera, and displays it on a television monitor; An X-ray imaging apparatus having an automatic control system that controls the exposure conditions of the X-rays by detection by a light amount detector, further comprising a light amount distribution member that distributes the light amount of the optical image to a plurality of optical paths, An X-ray imaging apparatus characterized in that a system and an automatic control system are respectively arranged on different optical paths separated by the light amount distribution member. (2) The scope of the present invention is that the light amount distribution member is a half mirror, the television system is provided on the optical path through which the light from the optical image is reflected, and the automatic control system is provided on the optical path through which the light is transmitted. The X-ray imaging device according to item 1. (3) the light amount distribution member is a combination of two half mirrors, and the television system is provided on the optical path where the light from the optical image is reflected by the first half mirror;
The X-ray imaging apparatus according to claim 1, wherein the automatic control system is provided on the optical path reflected by the second half mirror, which is provided on the optical path transmitted through the first half mirror.