JPS5833366A - Optical diaphragm device of x-ray video device - Google Patents

Abstract

PURPOSE:To use a variable optical diaphragm as a fixed optical diaphragm and to obtain an aperture diameter stable against the disturbance, etc. of the control signal, by setting the aperture diameter by a control signal supplied from outside and at the same time setting manually the aperture diameter in case no control signal is supplied from outside. CONSTITUTION:A lens system is set into an X-ray video device to introduce the incident light given from an image intensifier into an image pickup tube. A set of plural aperture blades 6 of a diaphragm device of the above-mentioned lens system are held between a support plate 7 and a fixing plate. The aperture diameter of the blade 6 is driven by a driving mechanism 10 containing a driving galvanometer, a motor, etc. This mechanism 10 is fixed to a projected part 11 and then driven by the control signal given from outside. When no control signal is available, the aperture diameter is set manually by means of a fan plate 19 of an attachment plate 14 adhered to the mechanism 10. Thus a variable optical diaphragm is used as a fixed optical diaphragm device, and a stable aperture diameter is set to the disturbance, etc. of the control signal.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a variable optical aperture device for controlling the amount of light incident on an X-ray television camera imaging tube.

Conventionally, this type of optical aperture device cannot change the aperture diameter while the X-ray Eirin system is operating, so if the aperture diameter is set to the optimum diameter under fluoroscopy conditions, an excessive amount of light will enter the image pickup tube during imaging. , an X-ray television monitor causes halation,
It becomes difficult to recognize the image when photographing. Additionally, an image intensifier was required, making operation complicated.

For this reason, variable optical diaphragm devices are currently used which can change the aperture diameter by applying external control signals. Since the aperture diameter of the optical aperture device can be changed using an external control signal, the aperture diameter can be set separately for fluoroscopy and imaging, making it possible to obtain the optimal X-ray TV monitor brightness for each condition. can. Further, a decrease in output brightness due to deterioration of the image intensifier can be easily compensated for by an external control signal. However, in the absence of an external control signal, this conventional variable optical diaphragm device is not fixed at a constant aperture diameter due to vibrations of the optical diaphragm device, and the aperture diameter becomes unstable, causing malfunctions.

The present invention has been made in view of the above-mentioned circumstances, and when the aperture diameter of a variable optical diaphragm device cannot be controlled by an external control signal, the aperture diameter is fixed or the aperture diameter is manually controlled. It is an object of the present invention to provide a variable optical diaphragm device having a structure that allows

Next, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory diagram schematically showing an X-ray television system using an optical aperture device according to the present invention.

The image intensifier 1 and the image pickup tube 2 are arranged facing each other. Lens systems 3 and 4 are arranged between the image intensifier 1 and the image pickup tube 2 to allow light emitted from the image intensifier 1 to enter the image pickup tube 2. The lens systems 3 and 4 are image intensifiers 1
It consists of an objective lens 3 placed on the side and an X-ray television camera lens 4 placed on the imaging tube 2 side. An optical diaphragm device 5 is placed between the lenses 3 and 4. According to the X-ray television system configured in this way, the light emitted from the image intensifier 1 is transmitted through the lens 3. Optical aperture device5. The light passes through the lens 4 and enters the image pickup tube 2. The hidden optical diaphragm device 5 limits the amount of light incident on the image pickup tube 2 based on an external control signal (not shown) K.

FIGS. 2 to 4 are explanatory diagrams schematically showing an optical diaphragm device that is an embodiment of the present invention. FIG. 2 is a side view of the main part, FIG. 3 is a front view thereof, and FIG. 4 is a rear view thereof.

In FIGS. 2 to 4, a set of several aperture blades 6 is held at its upper surface by a support plate 7 and a stop plate 8. As shown in FIGS. The aperture blades 6 are driven via a lever 9 by a drive mechanism 10 composed of a driving galvanometer, a motor, or the like so that the aperture diameter changes. The drive mechanism 10
is fixed to a protrusion 11 on the upper surface of the support plate with a screw 12, and is driven by an external control signal (not shown). A latching means 13 for manually fixing the drive part of the drive mechanism 10 when there is no external control signal is attached to the drive mechanism 1.
The mounting fixed at 0 is attached to the plate 14. A guide 17, which has an opening 16 in a part that controls the movement of the drive part of the drive mechanism 10 and is arranged to straddle the lever 9, fixes the drive mechanism 10 to the protrusion 11 on the back surface of the support plate 7. They are commonly fixed by screws 12. Drive mechanism 1
The drive unit 0 includes a drive shaft 18 that protrudes from the drive mechanism 10 and rotates in response to an external control signal, and a sector-shaped fan plate 19 that is arranged parallel to the support plate 7 and fixed to the drive shaft 18. and a guide pin 20 that passes through the opening 16 provided in the support plate 7 and the guide 17 and is fixed perpendicularly to the fan plate 19.
It consists of A manual lever 15 is attached to one end of the fan plate 19.
is fixed. Further, the other end of the fan plate 19 is attached to a hooking means 13.
It extends to the position where it is latched. Guide bin 20
is connected to a lever 9 that drives the aperture blade 6.

Next, referring to FIGS. 2 and 5, details of the structure of the latching means 13 will be described. FIG. 2 shows a case where the drive mechanism 10 is driven by an external control signal, that is, the latching means 1
FIG. 5 shows a state in which the drive mechanism 10 is free from external control signals, that is, the latching means fixes the drive part of the drive mechanism 10 to keep the aperture diameter constant. Indicates the state in which it is being held. A fixed attachment to the drive mechanism 10 is provided in the plate 14 with an aperture 21' at one end. A shaft 22 that rotatably penetrates the opening 21 has a manual knob 23 at one end, a Pane receiver end 24 at the other end, and a locking lever 26 with a hook 25 in the middle. There is. For attachment, a compression spring 27 is interposed between the plate 14 and the end 24 for the spring receiver of the shaft.

The core spring 27 imparts a unidirectional movement habit so that the shaft 22 moves in one direction. For the mounting fixed to the drive mechanism 10, a fixing base 29 having a recess 28 is fixed to the plate 14 in parallel with the shaft 22. The recessed portion 28 has a position and size that exactly engages with a hook 25 provided on the locking lever 26.

Next, the operation of the optical diaphragm device having the above configuration will be described.

A drive mechanism 10 composed of a drive galvanometer, a motor, etc. is driven and controlled by an external control signal (not shown). The drive shaft 18 is given rotational motion by the drive mechanism 10 . Drive shaft 1 is controlled by an external control signal.
8 rotates by a specified amount. This rotation rotates the fan plate 19, and the rotation of the cough fan plate 19 is transmitted to the lever 9 via the guide bin 20. The aperture diameter is set by moving the aperture blades by the movement of the lever 9. The guide pin 20 passing through the opening 16t of the guide 17 is for preventing malfunction of the drive mechanism 10 and controls the movement of the lever 9. Further, in order to maintain a constant aperture diameter in the absence of an external control signal, pull up the knob 23 of the latching means 13. Then, the engaged hook 25 of the locking lever 26 is released from the four parts 28 of the fixing base 290. after that,
When the knob 23 is rotated, the shaft 22 is moved downward by the compression spring 27, and the end 24 of the shaft 22 comes into contact with the fan plate 19, causing the fan plate 197f! : Lock. Therefore, in the absence of an external control signal, the aperture diameter is held constant without being affected by vibrations of the drive mechanism 10 or the like. In addition, when the knob 23 is rotated in this state, the spring receiver 24 and the fan plate 19
Since the tip of the fan plate is in strong contact with the tip of the fan plate, a rotational moment is applied, and the force of the fan plate 19 moves once, thereby making it possible to manually control the diameter of the aperture.

The strength of the compression spring 270 is determined by the strength of the compression spring 270 between the end 24 of the shaft 22 and the fan plate 1.
It is selected according to the frictional force with 9.

In addition, the above embodiment is a car in which the end 24 of the shaft 22 presses the fan plate 19 by means of a compression lever 27, and in another embodiment, the locking lever 26 and the attachment are interposed between the plate 14. A configuration in which the end portion 24 of the shaft 22 presses the fan plate 19 using a tension spring is also possible.

Although one embodiment of the present invention has been described in detail above, the present invention is not limited to the above-mentioned embodiment and includes various modifications without changing the gist of the present invention.

According to the present invention described in detail above, the following effects can be achieved. That is, the aperture diameter can be set by an external control signal, and the aperture diameter can be set manually if there is no external control signal. Therefore, the variable optical diaphragm can also be used as a fixed optical diaphragm, and the diaphragm diameter can be easily fixed using the latching means. It is also possible to obtain the specified aperture diameter with a separator.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram schematically showing an X-ray television system in which an optical diaphragm device according to the present invention is used, and FIG. 2 is a side view of main parts schematically showing an optical diaphragm device that is an embodiment of the present invention.
Figure 3 is a front view of Figure 2, Figure 4 is a rear view of Figure 2, and Figure 5 is an enlarged view of the locking means in Figure 2, where the locking means fixes the aperture diameter. FIG. 5... Optical aperture device, 6... Aperture blade, 9...
- Shibar, 10... Drive mechanism, 13... Latching means, 18... Drive shaft, 19... Fan plate, 2o
...Guide bin. Agent: Patent Attorney Noriyuki Chika (and 1 other person) Figure 1 Figure 3 Figure 4 Figure 5

Claims (3)

[Claims] (1) When installed in an X-ray imaging device consisting of an image intensifier, an image pickup tube disposed opposite to the image intensifier, and a lens system that makes light emitted from the image intensifier enter the image pickup tube, A drive mechanism that drives and controls the aperture aperture formed by a set of several aperture blades and a core aperture blade using a control signal, and when the drive mechanism is free from the control signal, the aperture aperture formed by the aperture blades. 1. An optical aperture device for an X-ray imaging device, comprising means for manually driving and controlling an aperture aperture. (2) The drive/control means for manually controlling the drive part of the drive mechanism is fixed to the optical diaphragm device.The mounting has an opening that rotatably penetrates the plate, with a manual knob at one end and a spring holder at the other end. a compression spring interposed between the spring receiver and the mounting plate; and the mounting has one end fixed to the plate and a recessed part at the other end. and a fixing base having a fixing base, and when the hooking pawl engages with the recess by rotating the shaft, the driving part of the drive mechanism is released, and when the hooking pawl does not engage with the recess. 2. An optical diaphragm device for an X-ray imaging apparatus according to claim 1, wherein the drive portion of the drive mechanism is fixed. (3) The means for manually driving and controlling the drive part of the drive mechanism has a hole in the optical diaphragm device.The mounting means is a locking lever that rotatably penetrates the plate and has a manual knob and a catch claw at one end. a tension spring interposed between the locking lever and the mounting plate; and a fixing base having one end fixed to the mounting plate and a recessed part at the other end, and rotating the shaft. According to the patent, the driving part of the drive mechanism is released when the hooking pawl engages with the recess, and the driving part of the drive mechanism is fixed when the hooking pawl does not engage with the recess. The optical diaphragm device for an X-ray imaging device according to item 1. −