JPS6037920B2 - X-ray image storage display element - Google Patents

Description

[Detailed description of the invention] The present invention relates to a novel X-ray image storage and display device.

Recently, various X-ray image forming methods that do not use silver halide emulsion films (hereinafter referred to as ray salt films) have been announced.

A representative example of this is xeroradiography, which utilizes the X-ray sensitivity of photosemiconductors.
It has been commercialized as 5. On the other hand, there is something called ionography that uses electromagnetic phenomena in gases and insulating liquids. Both xeroradiography and ionography are development methods that utilize electrophotography, and their characteristic edge effect makes it very easy to distinguish low-contrast areas where conventional silver halide films could not obtain satisfactory images. However, xeroradiography generally has low sensitivity, and ionography requires care to prevent changes in conductivity due to contamination of the insulating liquid, resulting in a large-scale apparatus. Therefore, attempts have been made to seal an insulating liquid in a closed chamber, form a latent image outside the chamber, and develop this latent image either directly or by transfer. That is, as shown in FIG. 1, there is a highly insulating film 3 that is parallel to and opposite to the highly radiolucent electrode 2 with a spacer 4 in between, and the electrode 2 and the highly insulating film 3. A chamber 1 filled with an insulating liquid 5 with high radiation absorption efficiency is arranged between the chambers as shown in FIG. In this method, an electrostatic latent image is formed on the surface of the chamber 1 by charging the chamber 1 with reverse polarity while irradiating radiation through the chamber 1, and this is developed by a conventional electrophotographic method. However, when this chamber 1 is enlarged for practical use and used in a nearly vertical position for chest radiography, the three legs of the highly insulating film are pushed downward by the gravity of the insulating liquid 5, as shown in FIG. It deforms into a crab-shaped protrusion and becomes unusable. Further, development by such electrophotography requires a development process for visualization, and this has the disadvantage of lowering resolution and the like. The present invention has been made in view of the above circumstances, and its object is to provide an X-ray image storage/display element that can store X-ray images, observe them in ambient light, and erase them freely.

Embodiments of the present invention will be described below with reference to FIG. 4 and subsequent figures.

As shown in FIG. 4, the X-ray image storage and display element of the present invention has the following features:
The electrode 11 with high X-ray transparency, the insulating liquid 12 with high X-ray absorption efficiency, the dielectric mirror layer 13, the strong electrolytic layer and the anti-strong electrolytic layer or the normal electrolytic layer have a compositional transformation phase boundary. Coexisting electro-optic ceramic solid solution 14, transparent electrode. 15 are stacked,
The insulating liquid 12 is sealed between the electrode 11 and the dielectric mirror layer 13 at a spacer 16. The ceramic solid body 14 used in the present invention, for example, PLZT, will be explained. PLZT is a Pb(Zr・Ti)03 solid solution containing La.
Ceramics Pb(,★)Lax(ZrkuQ
-y)Tiy), is an abbreviation for 03.

Its manufacturing method: Oxidized powders such as Pb0'TiQ'Zr02 and LA203 are mixed in a ball mill with distilled water for about 2 hours, dried at about 90 oo to solidify, and then 800 to 90 oo
P and T are calcined at 0qC for about 1 hour, and to make them uniform, they are ground, dried, and subjected to secondary calcining. After adding water, the powder is sieved through a 50 to 60 mesh nylon sieve to form a green compact, and then sintered by a hot press method applying a pressure of about 120 mm to obtain a transparent ceramic. The PLZT obtained in this way is
enaelectric, Phase) and Anti-Strong Telephone Minister (
The compositional transformation phase (Morphotropic, PhaseBo) has a phase boundary (Morphotropic, PhaseBo) that does not change much with respect to temperature, and if this transition is primary, the thermal history is large, and when cooling from a high temperature and heating from a low temperature, the composition transformation phase boundary occurs at a different location with respect to temperature or composition, and there is a region sandwiched between the cooling composition transformation boundary and the heating composition transformation boundary. One phase is stable and the other phase is metastable, and both phases can coexist.

When the strong fin phase and the anti-strong fin phase coexist in the temperature range of the thermal history, a double hysteresis curve as shown in FIG. 5 is shown. The above-mentioned P is 0.05 mm x 0.1, 0.6 mm y 0.0. 8 generally has a wide temperature range of thermal history, and PWT7.6/
At 70/30, it reaches about 15 qo. Moreover, this ceramic solid solution 14 is an anti-strong mysterious electric material that does not disturb light;
When a voltage is applied, a strong mysterious electric phase with a different crystal structure is induced and light is scattered violently. Therefore, the X-ray image storage/display element according to the present invention as shown in FIG. 4 is configured as shown in FIG. When X-rays are irradiated through the object 9, the insulating liquid 12 is applied to the
Negative ion pairs or positive ions and electrons are generated and each moves to the corresponding electrode side. CC So3 is an insulating liquid.
, CC-3Br, CC-31, and other molecular mixed compounds containing elements with an atomic number of 17 or more may be used. That is, the insulating liquid 12 that has been irradiated with X-rays becomes conductive, and changes the electric field strength on both sides of the ceramic solid solution layer 14 to induce a strong electromagnetic phase. As can be seen from the double hysteresis curve in FIG. 5, this image-like polarization remains even after the voltage application to the transparent electrode 15 is stopped.
When light is irradiated from the side, the ferroelectric phase is strongly scattered, and the antiferroelectric phase is not scattered. Therefore, the image can be identified as a scattering image. To erase this image, the element can be heated to eliminate the strong electromagnetic phase. If erasing is desired in a short time, electrodes 16 and 17 are provided at both ends of the transparent electrode 15 and connected to the emitters of NPN transistors 18 and 19 respectively, as shown in FIG.
0 and 21, and the electrode 11 is grounded, gates A and B are alternately opened and closed at a period of several milliseconds to several tens of milliseconds, and a pulse voltage of several tens of volts is applied. In this way, current flows alternately in the transparent electrode 15, and the potential on the transparent electrode 15 varies over time and location, but when averaged over time, it acts as a uniform reverse voltage between the two electrodes, At the same time, the image can be completely erased in a fraction of a second because it can be heated to a certain temperature using Joule heat without strong transference. As described above, the X-ray image storage display element according to the present invention includes an insulating liquid 12 having a high X-ray absorption rate, an electrode 11, a dielectric mirror layer 13, and a substrate 1.
It is enclosed in a hard material such as No. 6, so even if it is enlarged and used vertically, a part of it will not deform into a curved shape due to the weight of the insulating liquid 12, and furthermore, the image after shooting is It can be stored for any length of time, the image can be viewed in ambient light, and it can be erased at will when no longer needed.

In addition, since no voltage is required for image storage, it can be carried around not only for fluoroscopy. It can also be used for diagnosis and observation. Furthermore, if you wish to save the image as a hard copy, you can copy it using a mirror surface or the like using a secondary electronic copying machine.

[Brief Description of the Drawings] Figure 1 is a sectional view of a chamber used in conventional ionography, Figure 2 is a diagram explaining its operation, Figure 3 is a diagram explaining its defects, and Figure 4 is a diagram showing the implementation of the present invention. A sectional view showing an example, FIG. 5 is a double hysteresis curve of the ceramic solid solution used in the present invention, and FIGS. 6, 7, and 8 are diagrams explaining its operation. 11 is an electrode, 12 is an insulating liquid, 13 is a conductive specular layer,
14 is an electro-optic ceramic solid melt, 15 is a transparent electrode, 1
6 is subesa. Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 7 Figure 5 Figure 8

Claims (1)

[Claims] 1 An electrode 11 with high X-ray transparency, an insulating liquid 12 with high X-ray absorption efficiency, a dielectric mirror layer 13, an electric current in which a ferroelectric phase and an opposite dielectric phase or a paraelectric phase coexist with a compositional transformation phase boundary. An X-ray image storage and display element characterized in that an optical ceramic solid solution layer 14 and a transparent electrode 15 are laminated, and the insulating liquid 12 is sealed between the electrode 11 and the dielectric mirror layer 13 with a spacer 16.