JPS6294068A - Light beam scanner - Google Patents

Abstract

PURPOSE:To properly convey a body to be scanned by arranging two sets of rollers, which hold the body to be scanned such as an accumulative luminescent sheet and convey it in terms of subscan, so that they are separated by a shorter distance than the length of the body to be scanned in the conveyance distance and rotating them synchronizingly. CONSTITUTION:An interval between two pairs 26 and 28 of rollers comprising a sheet subscan conveyance mechanism 24 is selected shorter than the length of the accumulative luminescent sheet A in the conveyance direction, and two pairs 26 and 28 of rollers are synchronizingly rotated. As a result, the accumulative luminescent sheet A is held by the 1st pair 26 of rollers so as to displace in the direction of an arrow B. Then its end side is held by the 1st pair 26 of rollers, and the tip side of the sheet is faced with the 2nd pair 28 of rollers while the sheet is extracted, whereby the sheet can be smoothly conveyed from the 1st pair of roller to the 2nd pair 28 of rollers.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a light beam scanning device, and more particularly, to a light beam scanning device that scans a scanned object two-dimensionally with a light beam, for example, a stimulable phosphor sheet on which a radiation image is stored and recorded. The present invention relates to a light beam scanning device that performs reading by irradiating excitation light onto a photographic light-sensitive material, or records an image on the photographic light-sensitive material by irradiating a light beam onto the photographic light-sensitive material.

Recently, a radiation image recording and reproducing system that obtains a radiation image of a subject using a stimulable phosphor (stimulable phosphor) has been attracting attention. Here, the term phosphor refers to radiation (X-rays, α
When irradiated with radiation, β-rays, electron beams, electron beams, ultraviolet rays, etc., a part of this radiation energy is accumulated, and later when excited light such as visible light is irradiated, stimulated luminescence light corresponding to the accumulated energy is generated. A fluorescent material that emits light.

The radiation image recording and reproducing system described above utilizes this stimulable phosphor, and the radiation image information of a subject such as a human body is stored on a sheet having a layer made of a stimulable phosphor (hereinafter referred to as a ``stimulable phosphor sheet''). (or simply referred to as a "sheet"), this stimulable phosphor sheet is scanned with excitation light such as a laser beam to generate stimulated luminescent light, and the stimulated luminescent light is read photoelectrically. An electrical signal is obtained, and based on this electrical signal, a radiation image of the subject is output as a visible image to a recording material such as a photographic light-sensitive material or a display device such as a CRT.

Therefore, in such a radiographic image recording and reproducing system, an image reading device that reads a radiographic image from a stimulable phosphor sheet on which the radiographic image is stored and recorded specifically reads the radiographic image by the following method. reading.

That is, a stimulable phosphor sheet is scanned two-dimensionally with a light beam such as a laser beam, and the spontaneously emitted stimulated luminescence light is detected in time series with a photodetector such as a photomultiplier to obtain image information. get.

In the two-dimensional scanning of the light beam, the light beam is normally deflected and irradiated onto the stimulable phosphor sheet in a -dimensional manner to perform main scanning, and the sheet is scanned in a direction substantially orthogonal to the main scanning direction. This is achieved by mechanically conveying the image using a belt conveyor or the like, and thereby performing sub-scanning.

Next, the image information obtained as described above is sent to an image recording device. The image recording device irradiates a photographic light-sensitive material, which is a recording material, with a laser beam modulated based on the image information obtained from a stimulable phosphor sheet to record a predetermined image on the photographic light-sensitive material. It is composed of

After the photographic light-sensitive material on which the new image has been recorded is subjected to development processing, it is stored at a predetermined location and used for medical diagnosis, etc., as necessary.

Incidentally, in an image reading device, the stimulable phosphor sheet conveyed by a belt conveyor must be firmly positioned and fixed on the belt conveyor. That is, if the stimulable phosphor sheet moves on the belt conveyor during scanning, the irradiation position of the light beam on the stimulable phosphor sheet shifts from the desired position, and as a result, as described above, the belt Continuing to scan the stimulable phosphor sheet with the laser beam after it has been displaced by 7 relative to the conveyor will result in inaccurate image information. In other words, it is no longer possible to obtain accurate radiographic image information from the stimulable phosphor sheet that has caused the positional shift, and therefore, if the subject is a patient, there may be inconveniences such as the possibility of medical diagnosis errors. Reveal.

Therefore, in order to prevent the stimulable phosphor sheet from being displaced with respect to the belt conveyor during scanning, for example, a saccharging box is conventionally used. That is, the suction box is disposed in a space of an endless belt conveyor, and the belt conveyor is provided with a plurality of suction holes. Then, when the stimulable phosphor sheet is conveyed to the held conveyor, a vacuum generator connected to the suction box starts suction, and the stimulable phosphor sheet is suctioned onto this heald conveyor. It is positioned and fixed on the heddle, and is transported as the belt conveyor is displaced in the sub-scanning direction.

However, in this type of conventional technology, since the suction box is used as described above, the mechanism is complicated and large, and the vacuum generator that sucks the sheet through the suction box and this device are required. A control system is required to drive and control the

Moreover, the fixed conveyance means for such a stimulable phosphor sheet becomes quite expensive, and the cost of the entire radiation image recording and reproducing system also rises considerably.

Furthermore, in order to suitably adsorb the stimulable phosphor sheet onto the held conveyor, a conveyance path must be provided for conveying the bulk phosphor sheet parallel to the belt conveyor. With such a configuration, the radiation image recording and reproducing system itself becomes large-sized. For this reason, particularly when the system is placed in a hospital or the like, it is pointed out that there is a drawback that it is difficult to effectively utilize a narrow room.

On the other hand, an image recording apparatus performs main scanning by deflecting and irradiating a photosensitive material with a modulated laser beam. Sub-scanning is performed by holding the paper between a pair of rollers and conveying it in a direction substantially perpendicular to the main-scanning direction.

However, in this case, when transporting the photographic light-sensitive material, there is a risk that load fluctuations may occur in a rotary drive source, such as a motor, which rotationally drives the drum, so that suitable sub-scanning may not be performed on the photographic light-sensitive material. arise. Therefore, conventionally, support stands are provided before and after the drum in the sub-scanning direction to minimize load fluctuations on the motor during sub-scanning.

Therefore, it is necessary to provide a support stand having a length equal to or longer than the length of the photosensitive material being conveyed in the sub-scanning direction at least before and after the drum, and the image recording apparatus itself is quite large. The flaws that become apparent are exposed. In addition, the drum is used to stably convey the photosensitive material.
The width of the image recording device is larger than that of the photographic photosensitive material, and the motor for rotating the drum is provided in the width direction of the drum, so the image recording device can extend widely in the main scanning direction as well. I have no choice but to.

Furthermore, in order to perform highly accurate scanning of photographic materials,
It is necessary to strictly control the motor to convey the photosensitive material at a constant speed in the correct direction with high precision, and since high-precision motors that can be controlled as described above are expensive, There is also the problem that the cost increases significantly. In addition, in order to stably convey the photographic material, it is essential to provide a pair of rollers that come into sliding contact with the drum. Scanning cannot be performed at both ends in the scanning direction, for example, a black frame around the image, so-called
This causes the inconvenience of not being able to meet the demand for blank edges.

The present invention has been made in order to overcome all the above-mentioned disadvantages, and the present invention has been made in order to overcome all of the above-mentioned disadvantages. By arranging two pairs of rollers at an interval shorter than the length in the direction and rotating the two pairs of rollers synchronously, the object to be scanned can be accurately and smoothly transferred in the sub-scanning direction with an extremely simple and compact structure. It is an object of the present invention to provide a light beam scanning device configured to suitably read or record images.

In order to achieve the above object, the present invention performs main scanning by irradiating a sheet-shaped object to be scanned with a light beam deflected in a one-dimensional direction, and also scans the object in a direction substantially perpendicular to the main scanning direction. In a light beam scanning device that transports a scanning object to perform sub-scanning and two-dimensionally scans the object to be scanned, a pair of rollers that sandwich and convey the object to be scanned are moved in the direction of conveyance of the object to be scanned. Two sets of rollers are arranged at an interval shorter than the length, and the two pairs of rollers are rotated synchronously to perform sub-scanning, and a deflected light beam is irradiated between the pair of rollers to perform main scanning. It is characterized by being configured as follows.

Next, preferred embodiments of the light beam scanning device according to the present invention will be described in detail with reference to the accompanying drawings.

In FIG. 1, reference numeral 10 indicates an image reading device incorporating a light beam scanning device according to the present invention. A supply magazine 14 is installed in the chamber 12 of the image reading device 10, and in this supply magazine 14, laminated phosphor sheets A) in which radiographic images have been stored and recorded are stored in a stacked manner. There is.

In the vicinity of the supply magazine 14, a sheet mechanism including a suction cup 16 is provided in the chamber 12, and below the suction cup 16 there is an endless column for transporting the stimulable phosphor sheet 1-A. One conveyor belt 18 is provided.

The first conveyor belt 1 extends vertically downward, is bent at an internal corner of the image reading device 10 so as to be oriented horizontally, and is in contact with one surface of the first conveyor belt 1-18. A plurality of rollers 20a to 20d arranged in the vertical direction are provided. Furthermore, a large-diameter roller 22 is disposed at the lower bent portion of the first conveyor belt 18 . Therefore, a sheet sub-scanning conveyance mechanism 24 is provided at a slight distance from the terminal end of the first conveyance belt 18.

As shown in FIGS. 1 and 2, the first and second roller pairs 26 and 28, respectively, constituting the sheet sub-scanning conveyance mechanism 24 are arranged at a predetermined distance from the length of the stimulable phosphor sheet A in the conveyance direction. They are placed at short distances apart. Said No. 10-
The roller pair 26 consists of a roller 30 that is rotationally driven and a roller 32 that rotates in sliding contact with the roller 30, while the 20th roller pair 28 has a roller 34 that has the same diameter as the roller 30 and is rotationally driven. and a roller 36 that rotates in sliding contact with the roller. In this case, the rollers 30 and 34 are rotated by the same rotational drive source via, for example, a belt or a chain.
It is possible to rotate in synchronization with 4 (in Fig. 2,
(see dashed line). Also, the 10th-Ra pair 26 and the 20th-Ra pair 2
A guide member 38 for holding the lower surface side of the stimulable phosphor sheet 1-A is provided between the guide member 38 and the stimulable phosphor sheet 1-A.
A guide member 40 is disposed above, and this guide member 40 has a slot-like opening 42 extending in a direction perpendicular to the conveyance direction of the stimulable phosphor sheet A. (See Figure 2).

A reading section 5 is provided above the sheet sub-scanning conveyance mechanism 24 described above.
6 is placed. The reading unit 56 includes a laser light source 58, and a mirror 62 and a galvanometer mirror 64 for scanning the laser light 60 on the sheet are provided on the laser light output side of the laser light #58, and the laser light 60 is directed to the aperture. The sheet A is scanned through the section 42. Further, at the scanning position of the laser beam 60 on the sheet, a light guide 6 whose incident end 68a enters the opening 42 faces the main scanning line.
8, and a photomultiplier 70 is installed above the light guide 68. In addition, on the opposite side of the light guide 680 incident end 68a across the scanning line, there is a condensing reflection mirror 66 that efficiently guides the stimulated luminescent light emitted from the stimulable phosphor sheet A to the incident end 68a. It is provided.

Next, an endless second conveyor belt 44 is provided adjacent to the 20th pair 28 . The second conveyor belt 44 extends a predetermined distance in the horizontal direction, then rises significantly in the vertical direction as shown in the figure, and is configured such that its tip end slightly descends after passing through a horizontal portion. In this case, a large-diameter roller 46 is disposed at the lower bent portion of the second conveyor belt 44, and a plurality of rollers 46 are disposed at the vertically extending portion of the second general conveyor belt 44.
8a to 48e are provided. 7. Also, a large diameter roller 50 and a roller 5 are provided at the upper bent portion of the second conveyance heald 44.
2a and 52b are provided to convey the stimulable phosphor sheet A vertically downward. A receive magazine 54 for storing the stimulable phosphor sheet A is provided adjacent to the roller 52b.

Furthermore, an erasing section 72 is disposed within the chamber 12, for example, between rollers 48b and 48c provided on the conveyor belt 44. Note that a plurality of erasing light sources (not shown) are provided inside the erasing section 72.

The image reading device incorporating the light beam scanning device according to this embodiment is basically configured as described above.
Next, its action and effects will be explained.

First, the X-ray magazine 14 is installed in the image reading device 10 . In this case, the supply magazine 14 includes:
For example, a plurality of stimulable phosphor sheets A on which radiation images of subjects such as human bodies are stored are stacked and stored.

Therefore, the stimulable phosphors -1-Δ are taken out one by one from the supply magazine 14 under the action of a sheet mechanism including a suction cup 16. A belt 18 and a plurality of rollers 20a to 20
d and the sheet sub-scanning conveyance mechanism 24 via the roller 22.
transported to the side.

Here, the stimulable phosphor sheet A is held between the tenth roller pair 26, that is, the rollers 30 and 32, and the arrow B.
transported in the direction. At this time, the laser beam 60 driven from the laser light source 58 by driving the reading section 56 is once reflected by the mirror 62, and then reaches the galvanometer mirror 64. is scanned on A, thereby causing sea 1-
The non-directional stimulated luminescence light emitted from A is reflected directly and by a reflecting mirror 66, and is incident on a light guide 68. Next, this is converted into an electrical signal by the photomultiplier 70 and sent to, for example, an image recording device.

In this way, the stimulable phosphor sheet A is two-dimensionally scanned by the light 60, and the stimulable phosphor sheet A is further held between the 20th pair 28. The image signal is conveyed in the direction of arrow B, passes through the reading section 56, and all of its image signals are read.

Next, the stimulable phosphor sheet A is transferred to the second conveyor belt 4.
4, reaches the erasing section 72 via the roller 46 and the rollers 48a and 4°8b. In the erasing section 72, a plurality of light sources (not shown) are turned on, so that the irradiated light completely erases the radiation image remaining on the stimulable phosphor sheet A. The stimulable phosphor sheet A from which the radiation image has been erased is conveyed to the upper part of the image reading device 10 via the second conveyor belt 44 and rollers 48c to 48e, and its progress is continued via the roller 50 and rollers 52a and 52b. It is stored in the receive magazine 54 with the direction deviated.

By the way, in this embodiment, the sheet sub-scanning conveyance mechanism 24
The distance between the pair of rollers 26 and 28 constituting the sheet is selected to be shorter than the length of the stimulable phosphor sheet 1-A in the conveyance direction, and the pair of rollers 26 and 28 are rotated synchronously. For this reason, the stimulable phosphor sheet A is first
After being pinched by the la pair 26 and displaced in the direction of arrow B in the figure, its rear end side is held and pushed out by the tenth la pair 26, and its tip side is moved to the 20th la pair 26.
8, from the 10th-Ra vs. 26 to the 20th-Ra vs. 2
8 can be transferred smoothly.

Moreover, the stimulable phosphor sheet A always has the roller pair 26
．． 28, the stimulable phosphor sheet 1-A does not move in a direction that deviates from the direction of conveyance. As a result, during the period after the leading end of the stimulable phosphor sheet 1-A enters the 10th pair 26 and the rear end leaves the 20th pair 28, the stimulable phosphor sheet 1-A 1-A is conveyed accurately and smoothly without any positional deviation, and the radiation image of the stimulable phosphor sheet A can be read extremely well by the reading section 56.

Furthermore, since the guide members 38, 40 are provided between the roller pairs 26 and 28, the roller pairs 26 and 28, respectively,
The stimulable phosphor sheet A transferred between the 8 and 8 is suitably guided by the respective guide members 38 and 40 so that its leading end can face the 20th pair 28.

In addition, the guide member 40 is provided with a slit-shaped opening 42, and the stimulable phosphor sheet A can be accessed from the opening 42.
A laser beam 60 is irradiated onto the top.

Therefore, when transporting the stimulable phosphor sheet 1-A to the reading section 56 immediately after recording a radiation image of the subject, the afterglow of the instantaneous light emitted when the sheet A is irradiated with radiation is removed by the guide member 40. is prevented from reaching the light guide 68.

On the other hand, when the stimulable phosphor sheet A is irradiated with laser light 60, the sheet A emits stimulated luminescence according to the accumulated and recorded radiation image, but this stimulated luminescence disappears instantaneously. Instead, it has been confirmed that the phenomenon remains on the sheet as a stimulated luminescence afterglow for a predetermined period of time (see, for example, Japanese Patent Application No. 58-153691). However, the stimulated luminescence afterglow is caused by the guide member 4 in the same way as the instantaneous luminescent light.
0 and will not reach the light guide 68. In this way, since the guide member 40 prevents the m-directed light and the stimulated luminescence afterglow from entering the light guide 68, the radiation image information obtained from the stimulable phosphor sheet 1-A is It becomes even clearer and more accurate.

Furthermore, each roller pair 26.
Since the image reading device 10 is conveyed while being held by the image reading device 28, there is no need for the portions of the respective conveyance healds 18 and 44 that are close to the pair of rollers 26 and 28 to extend in the horizontal direction. It becomes possible to downsize as much as possible.

By the way, the radiation image recording and reproducing system employs an image recording device in order to permanently record the radiation image information once stored in the stimulable phosphor sheet onto the recording material as described above. The photographic light-sensitive material is irradiated with modulated laser light to record a predetermined image on the photographic light-sensitive material based on the radiation image information. Therefore,
If the sheet sub-scanning conveyance mechanism 24 of this embodiment described above is applied to the image recording apparatus, the photographic light-sensitive material can be conveyed accurately and smoothly, and the image recorded on the photographic light-sensitive material can be easily scratched. It is easy to understand that it will be good for the first time.

Next, a sheet sub-scanning conveyance mechanism according to another embodiment of the present invention is shown in FIGS. 3 and 4. In the second embodiment shown in FIG. 3, the sheet sub-scanning conveyance mechanism 24a is The constituent roller 80 is engaged with a rotational drive source (not shown), and a heald 84 is suspended between the roller 80 and a roller 82 having the same diameter. In this case, the separation distance between the rollers 80 and 82 is selected to be a predetermined length shorter than the length of the stimulable phosphor sheet to be transported in the transport direction. A small diameter roller 86 is disposed above the roller 80, and a roller 88 is disposed above the roller 82.

Therefore, if the rotation drive source (not shown) is driven to rotate the roller 80 in the direction of the arrow, the roller 80 will be rotated through the belt 84.
2 rotates synchronously. Here, when the stimulable phosphor sheet A is conveyed between the rollers 82 and 88, the stimulable phosphor sheet 1-A is conveyed in the direction of the arrow through the heald 84 and the roller 88. Further, the leading end portion thereof is held between a belt 84 and a roller 86 and conveyed. that time,
Since the rollers 80 and 82 rotate synchronously as in the first embodiment described above, the stimulable phosphor sheet A can smoothly pass through the sheet sub-scanning conveyance mechanism 243.

Further, between the rollers 88 and 86, the stimulable phosphor sheet A is placed on a belt 84, and the belt 84 does not function as the guide member 38 shown in the first embodiment. ing.

Furthermore, a third embodiment is shown in FIG.

In this case, a roller 90 constituting the sheet sub-scanning conveyance mechanism 24b is engaged with a rotational drive source (not shown), and a roller 92 having the same diameter as this roller 90 rotates synchronously via a belt 94. is configured to do so.

Furthermore, two pairs of rollers 96 and 98 are arranged to sandwich the heald 94. The distance between the pair of rollers 96 and 98 is a predetermined length longer than the length of the stimulable phosphor sheet A in the conveyance direction, as described in the first embodiment and the second embodiment. Selected short.

Therefore, when the roller 90 is rotated, the roller 92 and the roller pair 96.98 are rotated via the heald 94, and the stimulable phosphor sheet 1-A that has been conveyed to the sheet sub-scanning conveyance mechanism 24b is first , its tip end is held between a pair of rollers 96 and conveyed together with the belt 94 in the direction of the arrow. Next, the stimulable phosphor sheet A is conveyed in the direction of the arrow with its rear end side being held between the pair of rollers 96 and between the pair of rollers 98. In this case, each roller pair 96
．． 98 rotates synchronously, the stimulable phosphor sheet A
It is easily understood that the can be conveyed smoothly and accurately.

As described above, according to the present invention, an object to be scanned, such as a stimulable phosphor sheet, is sandwiched and conveyed in the sub-scanning direction. Set arrangement U7.11: The two forceps described in 1 are not paired and the rollers are rotated synchronously. Therefore, the object to be scanned is accurately conveyed while being held between at least one pair of rollers, and is also extremely smoothly transferred to the other pair of rollers. Therefore, for example, when a stimulable phosphor sheet is irradiated with excitation light to obtain radiation image information, or when a photosensitive material is irradiated with laser light to obtain a visible image, clear and good image information or It becomes possible to obtain a visible image. Furthermore, since the structure of the sub-scanning mechanism is simple, it can be manufactured at a low cost and can be made as small as possible, and the device itself in which the light beam scanning device is incorporated can be suitably compacted to take up less space than the device occupies. This has the effect of further reducing the area.

Although the preferred embodiments of the light beam scanning device according to the present invention have been described above, the present invention is not limited to these embodiments, and various improvements and modifications can be made without departing from the gist of the present invention. Of course, the design can be changed.

[Brief explanation of drawings]

FIG. 1 is a schematic explanatory diagram of an image reading device incorporating a light beam scanning device according to the present invention, FIG. 2 is a schematic explanatory perspective view of a sea+-sub-scanning conveyance mechanism, and FIG. 3 is a diagram according to a second embodiment. FIG. 4 is a schematic explanatory diagram showing a sheet sub-scanning conveyance mechanism according to a third embodiment. DESCRIPTION OF SYMBOLS 10... Image reading device 14... Supply magazine 18... Conveyance belt 24.24a, 24b... Sheet sub-scanning conveyance mechanism 26
．． 28... Roller pair 30.32.34.36... Roller 3rd, 40... Guide member 42... Opening 44
...Transport belt 54...Receive magazine 56...Reading section 58...Laser light source 6
0... Laser beam 64... Galvanometer mirror 66... Reflection mirror 66... Condensing optical element 70... Photo multiplier 72... Erasing unit 80.82... Roller 84... Held 86.88.90.92...Roller 94...Belt 96.98...Roller Monthly patent applicant Fuji Photo Film Co., Ltd.-"i,
'- FIG, 3 FIG, 4

Claims (7)

[Claims] (1) Main scanning is performed by irradiating a sheet-shaped object to be scanned with a light beam deflected in a one-dimensional direction, and sub-scanning is performed by transporting the object to be scanned in a direction approximately perpendicular to the main scanning direction. In the light beam scanning device that scans the object to be scanned two-dimensionally, two pairs of rollers that sandwich and convey the object to be scanned are arranged at an interval shorter than the length of the object to be scanned in the conveying direction. The two pairs of rollers are rotated synchronously to perform sub-scanning, and a light beam deflected between the pair of rollers is irradiated to perform main scanning. Light beam scanning device. (2) In the apparatus according to claim 1, a driving belt member is stretched between each roller in two pairs of rollers, and one of the rollers is driven to rotate. and the two pairs of rollers are rotated synchronously via the belt member. (3) A light beam scanning device according to claim 1, wherein a guide member for holding at least one surface of the object to be scanned is provided between two pairs of rollers separated by a predetermined distance. . (4) In the apparatus according to claim 1, a belt member is stretched between two pairs of rollers, and the belt member is held between the pair of rollers. and a light beam scanning device in which one of the first rollers is rotationally driven to synchronously rotate two pairs of rollers that are in sliding contact with the belt member. (5) In the apparatus according to claim 1, a belt member stretched over a roller rotating under the action of a rotational drive source is held between two pairs of rollers separated by a predetermined distance;
A light beam scanning device in which the two pairs of rollers are rotated synchronously via the belt member. (6) In the apparatus according to any one of claims 1 to 5, the object to be scanned is made of a stimulable phosphor sheet on which image information is recorded, and an image is emitted by light beam irradiation. A light beam scanning device that photoelectrically reads stimulated luminescence light according to information. (7) In the apparatus according to any one of claims 1 to 5, the object to be scanned is made of a photographic material,
A light beam scanning device that records images by irradiating a light beam.