JPH055738B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a conveying device for a stimulable phosphor sheet, and more particularly to a device for recording and/or reading radiation image information of a subject by conveying a stimulable phosphor sheet. / and a stimulable phosphor that enables image information obtained from the stimulable phosphor sheet to be made even clearer and more accurate by suitably eliminating static electricity charged on the stimulable phosphor sheet in a reading device. The present invention relates to a sheet conveying device.

Certain types of phosphors are exposed to radiation (X-rays, α-rays, β-rays,
When irradiated with γ-rays, electron beams, ultraviolet rays, etc., a part of the energy of this radiation is accumulated in the phosphor, and when the phosphor is then irradiated with excitation light such as visible light, it reacts with the accumulated energy. The phosphor emits stimulated light. A phosphor exhibiting such properties is called a stimulable phosphor.

Using this stimulable phosphor, radiation image information of a subject such as a human body is stored and recorded on a sheet of stimulable phosphor, and this sheet is scanned with excitation light to cause stimulated luminescence. A radiation image information recording and reproducing method has been proposed in which light is read photoelectrically to obtain an image signal, and this image signal is processed to obtain a radiation image of a subject with good diagnostic suitability (for example, Japanese Patent Application Laid-Open No. 12429/1983). , No. 56-11395, No. 55-163472
No. 56-104645, No. 55-116340, etc.). In this method, the final image may be reproduced as a hard copy or reproduced on a display device such as a CRT. In any case, in this radiation image information recording and reproducing method, the phosphor sheet does not ultimately record image information, but only temporarily carries image information, so this phosphor sheet is designed to be used repeatedly. You can also
Moreover, if it is used repeatedly in this way, it is extremely economical.

A radiation image information recording and reproducing system applying the radiation image information recording and reproducing method as described above mainly includes an image information recording unit for irradiating a subject with radiation and recording the image information on a stimulable phosphor sheet, and the storage device. An image reading unit that irradiates excitation light onto a phosphor sheet to obtain stimulated luminescence light, converts the radiation image of the subject from an optical signal to an electrical signal, and records the image, and an image storage unit that records the image after reading is completed. and an erasing section for irradiating the radiation image remaining on the stimulable phosphor sheet with erasing light so that the stimulable phosphor sheet can be reused. The feeding of the stimulable phosphor sheet to these parts or the transportation of the stimulable phosphor sheet between these parts is carried out, for example, by
As shown in Japanese Patent Laid-Open No. 59-11240 and Japanese Patent Application No. 59-220740, this is carried out by a conveying system using rollers, endless belts, etc.

Incidentally, as shown in FIG. 1, the stimulable phosphor sheet used in the radiation image information recording and reproducing system generally consists of a support a, a phosphor layer b provided thereon, and a phosphor layer b provided thereon. It consists of a protective layer c for protecting the surface of the phosphor layer b, and a back layer d provided on the back surface of the support a. In this case, the protective layer c is formed of a film of polyethylene terephthalate, polyethylene, polyvinylidene chloride, polyamide or a cellulose derivative, and the back layer d is preferably made of polypropylene or the like.

The stimulable phosphor sheet A constructed in this manner is conveyed within a radiation image information recording/reading system by being held between rollers, an endless belt, etc. that constitute a conveyance system, but generally, the rollers and endless belt rubber are The stimulable phosphor sheet A is made of a rubber material or a phenolic resin material, and therefore, static electricity is often generated between the stimulable phosphor sheet A and this roller during transportation. That is,
When the protective layer c is made of polyethylene terephthalate, the protective layer c is charged between it and the roller, and a negative charge appears on the protective layer c. On the other hand, the backing layer d made of polypropylene is Positively charged.

Therefore, when attempting to obtain image information by feeding the storage layer phosphor sheet A charged in this way to the image reading section, the charge may appear as white streaks etc. in the radiation image information of the subject. and for this reason,
For example, when the subject is a patient, there is a problem in that the affected area cannot be accurately confirmed.

The present invention has been made in order to overcome the above-mentioned disadvantages, and is provided with a pair of charge eliminating means in close proximity to the photographing section, the image information reading section, etc. in the conveyance system, and the stimulable phosphor sheet is By passing through the static eliminating means in contact or in a non-contact state, the electric charge induced in the stimulable phosphor sheet is suitably removed, and unnecessary streaks etc. caused by static electricity do not appear, and therefore, the image is extremely clear. Another object of the present invention is to use a stimulable phosphor sheet conveying device that makes it possible to obtain accurate image information.

In order to achieve the above object, the present invention provides a transporting device for a stimulable phosphor sheet that transports the stimulable phosphor sheet by sandwiching it between a roller and an endless belt, or between rollers or endless belts, comprising: The present invention is characterized in that at least one pair of charge eliminating means is provided facing both sides of the phosphor sheet and facing each other.

Next, preferred embodiments of the stimulable phosphor sheet conveying apparatus according to the present invention will be described in detail in relation to a radiation image information recording and reproducing system incorporating the apparatus, with reference to the accompanying drawings.

Therefore, FIGS. 2 and 3 show a radiation image information recording and reproducing system for obtaining radiation image information using a stimulable phosphor sheet as described above.

In FIG. 2, reference numeral 10 indicates a standing type radiation image information recording/reading device, and the device 10 has a first housing 12 extending in the vertical direction and a second housing 14 extending in the horizontal direction. including. A photographing section 16 is disposed above the front surface of the first housing 12, and an operating section 18 is disposed above the side wall thereof.

FIG. 3 shows the internal structure of the first casing 12 and the second casing 14. That is, a pair of receiving rollers 20 that are in pressure contact with each other and are slightly displaced from the vertical direction are disposed below the photographing section 16, and a first guide member 22 that is inclined downwardly of this pair of rollers 20 and a first guide member 22 that is inclined downward and A second guide member 24 is provided that faces the guide member 22 and extends in the vertical direction. A pair of rollers 26 is further provided below the first and second guide members 22 and 24, and a length longer than the stimulable phosphor sheet A is provided below the pair of rollers 26. A slightly shorter third guide member 28 is provided. Note that a pair of rollers 32 is pivotally supported between the third guide member 28 and a fourth guide member 30 provided below. Further, a pair of rollers is provided below the fourth guide member 30.

Next, the first housing 12 is placed below the roller pair 34.
A conveyor belt 36 is provided at an internal corner of the conveyor belt 36 . In this case, a first roller group 38 consisting of three rollers is disposed at the bent portion of the conveyor belt 36, as shown in the figure, and a fifth guide member 40 is disposed above the first roller group 38. will be placed. The conveyor belt 36 terminates at the lower central portion of the second housing 14 .
Next, an endless second conveyor belt 42 is disposed at a slight distance from the terminal end of the conveyor belt 36. This second conveyor belt 42 is connected to the second housing 1
It is bent upward at the corner of 4, and a second roller consisting of four rollers is installed at the inner bend.
A roller group 44 is provided. Further, a pair of endless third conveyor belt 46 and fourth conveyor belt 48 extend horizontally at a distance from the terminal end of the conveyor belt 42 . The third conveyor belt 46 and the fourth conveyor belt 48 are arranged at a predetermined distance from each other, and a small-diameter roller 50 is rotatably arranged at the spaced apart portion. The rollers 52 and 54 located on the upper surface of the conveyor belts 46 and 48 have a pressing function to reliably hold the stimulable phosphor sheet A conveyed together with the small diameter roller 50.

On the other hand, an endless fifth belt 56 is provided which slides into contact with the terminal end of the fourth conveyor belt 48 and bends further upward. A third roller group 58 consisting of three rollers is provided on one side of the belt 56. A pair of opposing sixth guide members 60 is disposed above the fifth conveyor belt 56 and the third roller group 58.
A seventh guide member 64 is disposed above the guide member 64 via a pair of rollers 62 that are in contact with each other. As can be easily understood from FIG. 3, the seventh guide member 64 is shorter than the sixth guide member 60, and above the seventh guide member 64 is an eighth guide member. 66 are arranged. The eighth guide member 66 is formed by a pair of rollers 68 and 70 arranged above and below the eighth guide member 66 in relation to each other. That is, the distance between the roller pair 68 and the roller 70 is set to be much shorter than the vertical length of the stimulable phosphor sheet A to be conveyed.

By the way, another pair of rollers 74 is disposed above the pair of rollers 70 via a shorter ninth guide member 72, and between this pair of rollers 74 and the conveyor belt 76 of the next stage, Sixth guide member 6
A tenth guide member 78 having substantially the same length as 0 is provided. The end portion of the tenth guide member 78 is provided with an endless conveyor belt 76 that is close to the end portion of the tenth guide member 78 and is itself bent. As can be understood from the figure, the conveyor belt 76 is located approximately at the top of the first housing 12. As described above, since the conveyor belt 76 has a bending structure, a fourth roller group 80 consisting of seven rollers arranged on substantially the same circumference is provided inside the conveyor belt 76 . Note that the conveyor belt 76 and the fourth
Below the roller group 80 is a pair of rollers 82, 8.
4 is provided.

Here, in this conveyance system, a plurality of pairs of static eliminating means 86a to 86f are arranged at predetermined positions, respectively, as shown in the figure. First of all,
The static eliminating means 86a includes a conveyor belt 76 and a pair of rollers 82.
The static eliminating means 86b is provided below the roller pair 84. Furthermore, a static eliminating means 86c is provided between the roller pair 34 and the conveyor belt 36, and a static eliminating means 86d is provided between the conveyor belt 36 and the conveyor belt 42. Further, the conveyor belt 42 and the conveyor belt 46
A static eliminator 86e is provided between the guide member 60 and the roller pair 62, and a static eliminator 86f is provided between the guide member 60 and the roller pair 62. In this case, although the static eliminators 86a to 86f are used in this embodiment, it is easily understood that their number, placement location, etc. can be selected as necessary.

Next, details of the static eliminating means 86a will be explained with reference to FIGS. 4 and 5. A pair of static eliminating means 86
a has at least approximately the same length as the horizontal direction (direction perpendicular to the conveying direction) of the stimulable phosphor sheet A, and is made of aluminum, and holder members 88a and 88b, respectively.
A plurality of carbon brushes 90a and 9 are respectively fixed to b.
0b. In this case, the plurality of carbon brushes 90a and 90b are arranged to face each other, and their tips are spaced apart by a predetermined length _H1 , and this length _H1 is equal to the length H1 of the stimulable phosphor sheet A. The thickness is selected slightly larger than H ₂ . In other words, in this embodiment,
Although the stimulable phosphor sheet A is passed between the carbon brushes 90a and 90b in a non-contact state, the stimulable phosphor sheet A may also be passed in contact with the carbon brushes 90a and 90b. It is possible. Furthermore, the respective holder members 88a, 8
8b is grounded. Further, the other static eliminators 86b to 86f are configured similarly to the static eliminator 86a described above, and therefore detailed description thereof will be omitted.

The above is the basic configuration of the stimulable phosphor sheet conveyance system in the radiation image information recording/reading apparatus 10. Next, the image information reading section, erasing section, and imaging section arranged in relation to this will be explained.

First, the reading section 92 will be explained. Reading section 9
2 is disposed above the third conveyor belt 46 and the fourth conveyor belt 48, and the reading section 92 includes a laser light source 93. On the laser light output side of this laser light source 93, there is a mirror 95 and a galvanometer mirror 9 for scanning the laser light 94 onto the sheet.
6 and a condensing reflection mirror 97 are provided.
Further, a condensing optical element 98 is disposed along the main scanning line at the scanning position of the laser beam 94 on the sheet.
A photomultiplier 100 is attached to the top of the condensing optical element 98.

Next, the erasing unit 102 will be explained. Erase section 1
02 is a housing 10 provided opposite to the guide member 66
4, and the inside of this housing 104 includes a group of erase lamps 106 consisting of a large number of light sources, such as fluorescent lamps, tungsten lamps, halogen lamps, xenon lamps, and the like. In addition, the erasing light group 106
The casing 10 is
4. It is preferable to provide light shielding members 108 and 110 surrounding the lower end sheet inlet and upper end sheet outlet of the guide member 66 and the pair of rollers 68 and 70.

Furthermore, the photographing section will be explained. First housing 1
The internal space 11 of the photographing section 16 is bulged from 2.
2, a first plate 16 and a second plate 118 are provided oppositely, and the upper end of the first plate 116 is fixed, while the second plate 118 is attached to the photographing surface 158.
It is movable so as to come into close contact with the plate body 116, and is configured such that its upper end extends below the roller pair 84 when expanded. The lower ends of the first plate 116 and the second plate 118 are mutually supported by a shaft (not shown), and an opening defined at the lower end is opened and closed by a lid member (not shown). The opening is then adjacent to the roller pair 20 in the position shown in FIG.

Therefore, in the above configuration, the erasing section 1
The stimulable phosphor sheet A, from which the radiographic image information accumulated up to that point has been erased by the erasing lamp group 106 arranged at 02, passes through a pair of rollers 70, 74 and a guide member 78, and is bent by a conveyor belt 76 and a group of rollers 80. leading to. Further, the sheet A is held between the conveyor belt 76 and the roller group 80 and curved at a predetermined curvature, and then reaches the roller pair 82 . At this time, since the stimulable phosphor sheet A passes through a roller group 80 consisting of a plurality of rollers, a considerable amount of static electricity is generated in the stimulable phosphor sheet A, and the static electricity is retained on the sheet A. However, the stimulable phosphor sheet A passes through the static eliminating means 86a and is suitably neutralized.

That is, as shown in FIG. 5, the protective layer c of the stimulable phosphor sheet A is negatively charged;
The back layer d is positively charged. Then, when this stimulable phosphor sheet A enters the static eliminating means 86a,
Self-discharge occurs between the protective layer c and the plurality of carbon brushes 90a, while the plurality of carbon brushes 90a
Discharge development occurs between b and back layer d. As a result, this stimulable phosphor sheet A can be easily neutralized. In this case, for example, it has been proven that if the static eliminating means is provided only on the side of the protective layer c, the attractive force between the charges of the protective layer c and the backing layer d is large, so that a suitable static eliminating effect cannot be obtained. However, in the device of the present invention, as described above, it is possible to perform the static elimination action extremely effectively using the paired static elimination means.

Further, the stimulable phosphor sheet A passes through a pair of rollers 82 and 84, and then reaches a static eliminating means 86b. This static eliminating means 86b also performs a discharging action similar to that of the static eliminating means 86a described above.
The stimulable phosphor sheet A reaching the photographing section 16 can be completely neutralized. At this time, the first sensor 1 is placed between the roller pair 82 and the roller pair 84.
56, the photographing section 1 of the sheet A
You can easily confirm that you have reached 6.

Then, a motor (not shown) is driven and rotated to integrally displace the plates 116 and 118 toward the erasing section 102 side. That is, the plates 116 and 118 have their lower ends closed and their upper ends expanded. In this state, the stimulable phosphor sheet A is dropped and supplied to the holding member constituted by the plates 116 and 118. Next, the motor (not shown) is further driven, whereby the plate 11
6 and the plate 118 are displaced toward the photographing surface 158 while sandwiching the stimulable phosphor sheet A, and are held still in close contact with the photographing surface 158. That is, both plates 116 and 118 face the imaging surface 158 with the stimulable phosphor sheet A sandwiched between them, and are firmly positioned there.

At such a position, a subject (not shown) is irradiated with radiation, and a radiation image is photographed on the stimulable phosphor sheet A. When the photographing is completed, the motor which was in a stationary state is driven again to displace the plates 116 and 118 so that their upper ends are open. Then, when the plate 118 comes into contact with a pin member (not shown), the lower lid that had closed the lower ends of the plates 116 and 118 is opened, and the photographed sheet A falls downward. , and will be caught by the roller pair 20.
Note that a second roller is provided between the roller pair 20 and the roller pair 26.
If the sensor 160 is provided, the fall can be easily detected.

Next, this photographed sheet A is transferred to the guide member 2.
8, is conveyed to the static eliminator 86c via the roller pair 32, further passes through the roller group 38, and then reaches the static eliminator 86d. Then, the sheet A whose charge has been neutralized by the respective charge removal means 86 c and 86 d reaches the charge removal means 86 e via the roller group 44 and is conveyed to the reading section 92 via the conveyor belt 46 . Here, by leading the laser light 94 from the laser light source 93 and repeatedly vibrating the galvanometer mirror 96, the laser light 94 is main-scanned over the sheet A on which the radiation image has been accumulated and recorded. Further, a part of the stimulated luminescent light emitted from the sheet A irradiated with the laser beam 94 and the stimulated luminescent light reflected by the reflecting mirror 97 are transmitted from the incident end face of the condensing optical element 98 to the condensing optical element. 98
The light is guided through the light by total reflection and is received by the photomultiplier 100, where the stimulated luminescence light is read photoelectrically. At the same time that the main scanning of the laser beam 94 is performed as described above, the sheet A is moved by the conveyor belts 46 and 48 in the direction of arrow B in the figure (i.e., a direction substantially perpendicular to the main scanning direction).
The sheet A is conveyed to perform sub-scanning, and the radiation image information accumulated over the entire surface of the sheet A is read. Note that the image signal read by the photo multiplier 100 is transmitted to a signal processing circuit (not shown).

After the image information reading operation is completed in this way, the stimulable phosphor sheet A reaches the static eliminator 86f via the roller group 58, where the static electricity is removed, and then conveyed to the erasing section 102. Ru.

As described above, according to the present invention, a pair of static eliminating means is provided in the photographing section, the reading section, etc. in the transport system for the stimulable phosphor sheet. Therefore, the charged stimulable phosphor sheet can be passed through a plurality of roller groups to have its charge removed and then fed to the photographing section, the reading section, and the like. Therefore, unnecessary white lines and the like are not generated in the radiation image information of the subject, making it possible to obtain extremely accurate image information. Further, since the static eliminating means is disposed facing both sides of the stimulable phosphor sheet, discharge from the sheet is facilitated, and an even more effective discharge effect can be obtained.

Although the present invention has been described above with reference to preferred embodiments, the present invention is not limited to this embodiment. Furthermore, it goes without saying that various improvements and changes in design can be made without departing from the gist of the present invention, such as the position and number of the discharging means can be selected as necessary. be.

[Brief explanation of the drawing]

Fig. 1 is a partially omitted vertical sectional perspective view of a stimulable phosphor sheet, Fig. 2 is a perspective view of a radiation image information recording/reading device that uses a stimulable phosphor sheet to obtain radiation image information of a subject, and Fig. 3 is FIG. 2 is a schematic vertical cross-sectional view of the radiation image information recording/reading apparatus shown in FIG. 4
It is a schematic explanatory view of the action of the static elimination means shown in the figure. 10... Radiographic image information recording/reading device, 16...
...Photographing section, 18...Operation section, 26, 32, 34...
...roller pair, 36...conveyor belt, 38...roller group, 42...conveyor belt, 44...roller group,
46, 48, 56... Conveyor belt, 58... Roller group, 62, 68, 70, 74... Roller pair, 7
6...Transport belt, 80...Roller group, 82,8
4... Roller pair, 86a to 86f... Static elimination means,
88a, 88b...Holder member, 90a, 90b
... Carbon brush, 102 ... Erasing section, 158 ...
Shooting surface.

Claims (1)

[Scope of Claims] 1. In a stimulable phosphor sheet conveying device that conveys a stimulable phosphor sheet by sandwiching it between a roller and an endless belt, or between rollers or endless belts, both sides of the stimulable phosphor sheet 1. A transporting device for a stimulable phosphor sheet, comprising at least one pair of static eliminators facing each other and facing each other. 2. In the device according to claim 1,
The static eliminating means includes a holder member that is grounded and a plurality of static eliminating brushes that are fixed to the holder member,
The static eliminators are arranged to face each other, and the stimulable phosphor sheet is passed between the static eliminator brushes facing each other in a contact or non-contact state, so that both sides of the stimulable phosphor sheet are charged with different polarities. A stimulable phosphor sheet conveying device configured to simultaneously eliminate static electricity.