JPH10123636A - Dust removing method for radiation image reading device, and cleaning sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily remove the attached dust to a light converging system in a radiation image reading device. SOLUTION: By carrying a cleaning sheet 110 comprising a sheet-shaped base body 111 wider than a storage type fluorescent sheet and a strip-shaped brush 112 on the base body 111 in the width direction, the cleaning brush 112 of the sheet 110 wipes a light converging surface 58a of a light converging mirror 58 and an incident end face 54a of a light guide 54 to remove the dust attached to the light converging surface 58a and the incident end face 54a.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dust removing method for removing dust in a light condensing system of a radiation image reading apparatus and a cleaning sheet used in the dust removing method.

[0002]

2. Description of the Related Art By irradiating radiation, a part of the energy of the radiation is accumulated, and thereafter, by irradiating excitation light such as visible light or laser light, stimulated emission is performed in accordance with the accumulated radiation energy. The radiation image information of the subject such as a human body is accumulated on a sheet-like stimulable phosphor sheet formed by laminating a stimulable phosphor on a support using a stimulable phosphor (stimulable phosphor) indicating The recorded matter is scanned with excitation light to emit stimulated emission light, and the stimulated emission light is collected by a condensing mirror or a light guide, and the collected stimulated emission light is photoelectrically converted. A radiation image reading apparatus which obtains an image signal and irradiates the stimulable phosphor sheet after reading the image signal with erasing light to release the energy of the radiation remaining on the sheet is already well known.

An image signal obtained by this apparatus is subjected to image processing such as gradation processing and frequency processing suitable for observation and interpretation, and the image signal after this processing is applied to a diagnostic visual image. And reproduced on a film or a CRT for diagnosis and the like. On the other hand, the above-mentioned erasing enables the stimulable phosphor sheet to be used repeatedly.

In such a radiation image reading apparatus, a light-collecting system such as a light guide and a light-collecting mirror usually collects a weak stimulating light, so that a light-shielded portion (hereinafter referred to as a light-shielding chamber) is usually used. It is arranged in. However, since such a light-shielding chamber does not block the flow of air, dust enters the light-shielding chamber when the stimulable phosphor sheet is moved in and out, and the movement of the scanning system and the heat generated by the excitation light cause this. Dust flutters in the light-tight room and accumulates on the surface facing the light guide and the light collecting mirror over time.

[0005] The dust accumulated on the light-collecting system in this way often has an adverse effect on the reading of image information. For example, the distance between the condensing mirror and the light guide is set to be considerably narrow in order to maintain a high light condensing efficiency. Dust protrudes laterally from the edge, and excitation light having an optical path between the light collecting mirror and the light guide is blocked by the protruded dust, so that predetermined excitation energy cannot be given to the stimulable phosphor sheet.

[0006]

In a conventional radiation image reading apparatus, when dust actually adheres, the apparatus is disassembled to expose a portion to which the dust adheres, remove the dust, and reassemble the apparatus. Work was needed. However, there is a problem that the work of disassembling and assembling the components that have been finely adjusted and assembled cannot be performed by the user himself, and that it takes time to readjust.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a dust removing method and a cleaning sheet which can easily remove dust adhering to a light collecting system of a radiation image reading apparatus. Is what you do.

[0008]

According to the dust removing method of the radiation image reading apparatus of the present invention, the stimulable phosphor sheet on which the radiation image information is stored is transported by the transport means, and the stimulable phosphor sheet is conveyed to the stimulable phosphor sheet. A radiation image for irradiating excitation light, condensing stimulated emission light emitted from the stimulable phosphor sheet by a light condensing system having an incident end face located close to the sheet, and reading the radiation image information In the reading apparatus, there is provided a dust removing method for removing dust adhering to the incident end face from the incident end face, wherein the dust adhering to the incident end face is caused by conveying a cleaning sheet having a cleaning brush on a surface by the conveying means. Is removed.

The "light collecting system" is a general term for a light collecting mirror, a light guide and the like for collecting stimulated emission light, and the "incident end face" of the light collecting system is a light guide and a light guide. It is a generic term for a surface such as a condensing mirror on which stimulated emission light is incident.

[0010] The cleaning sheet of the present invention used in the dust removing method may be a sheet-like substrate conveyed by the conveying means, and wipes the entire incident end surface when the substrate is conveyed by the conveying means. And a cleaning brush provided on the substrate.

The base has a width equal to or greater than the width of the stimulable phosphor sheet, and the cleaning brush has a softness that does not damage the incident end face. It is desirable to form a strip in the width direction on the substrate.

[0012]

According to the dust removing method of the radiation image reading apparatus of the present invention, a cleaning sheet, which is a sheet-like substrate provided with a cleaning brush, is conveyed by the conveying means to adhere to the incident end face of the light collecting system. Since the dust is removed, the dust can be removed very easily. As a result, it is possible to prevent the luminous emission light emitted from the stimulable phosphor sheet from being condensed by dust.

Further, it is not necessary to disassemble the apparatus to remove dust, so that it is preferable to secure the precision of the apparatus. Further, it is necessary to reduce the cleaning time, which requires a long time because the apparatus includes disassembly and assembly. Can be.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the radiation image reading apparatus of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a schematic configuration of a radiation image reading apparatus, and FIG. 2 is a sectional view showing a section taken along line II of FIG. The illustrated radiation image reading apparatus includes a laser light source 51 that emits a laser beam L having a predetermined wavelength, and reflects and deflects the emitted laser beam L so that the laser beam L is mainly transmitted to the stimulable phosphor sheet 10 in the arrow X direction. Rotating polygon mirror 53 for scanning, rotating polygon mirror 53
An excitation light irradiating system including a motor 52 for rotating the laser, and a scanning lens 59 for converging the laser beam L reflected and deflected by the rotating polygon mirror 53 on the sheet 10 and scanning at a constant speed;
A light guide 54 for condensing stimulated emission light M emitted from the stimulable phosphor sheet 10, and a photomultiplier for amplifying the stimulated emission light M condensed by the light guide 54 and photoelectrically converting it into an image signal S (Hereinafter, referred to as PMT) 55, which is provided on the front surface side of the sheet 10 and which condenses the laser light L extending in the main scanning direction (the direction of arrow X) of the laser light L for efficiently guiding the stimulated emission light M to the incident end face 54a of the light guide 54. An image reading system including a mirror 58 and sheet conveying devices 21 and 22 which are belt conveyors that convey the stimulable phosphor sheet 10 in the direction of the arrow Y and convey a cleaning sheet 110 described later in the directions of the arrows Y and Y ′. It is a configuration provided. Here, in the image reading system, the light collecting mirror 58 and the light guide 54 for collecting the stimulated emission light are referred to as a light collecting system.

The radiation image reading apparatus has mode switching means (not shown), and the user switches from a normal image information reading mode to a cleaning mode for removing dust from the light condensing system as needed. It is a configuration that can be used. In the cleaning mode, the excitation light irradiation system and the image reading system are set not to operate.

In the cleaning mode, instead of the stimulable phosphor sheet 10, a sheet-like base 111 and a brush 112 formed in a band shape across the width of the base 111 as shown in FIG. Cleaning sheet 110 is used. The sheet width of the cleaning sheet 110 is wider than the width of the stimulable phosphor sheet 10, and the height h of the brush 112 is such that the tip of the brush 112 makes the entire light-collecting surface 58a of the light-collecting mirror 58 during conveyance of the sheet 110. Make it high enough to wipe. That is, the height h of the brush 112, the tip of the brush 112 needs to be higher than the height h _m of the sheet surface shown in FIG. 2 to the top of the light-collecting surface 58a. In the present embodiment, the height h is approximately 1 cm. In addition,
The brush 112 is formed by implanting a soft bristle material to such an extent that the light collecting surface 58a of the light collecting mirror 58 and the incident end face 54a of the light guide 54 are not damaged.

Next, the operation of the radiation image reading apparatus according to this embodiment will be described.

The user switches the mode between the image information reading mode for reading image information from the stimulable phosphor sheet and the cleaning mode for removing dust from the light condensing system by a mode switching means as necessary.

First, the operation in the image information reading mode for reading image information from the stimulable phosphor sheet will be described.

A laser light L having a predetermined wavelength is emitted from a laser light source 51.
The emitted laser light L is deflected in a predetermined direction by a rotating polygonal mirror 53 driven at high speed by a motor 52, and the deflected laser light L is scanned by a scanning lens 59 into a light guide 54 and a condenser mirror. 58 and converges on the surface of the stimulable phosphor sheet 10 at a constant speed.
10 is main-scanned in the arrow X direction. On the other hand, the sheet 10 is moved (sub-scanning) in the direction of the arrow Y by the sheet conveying devices 21 and 22, and the main scanning and the sub-scanning are combined so that the entire surface of the sheet 10 is uniformly irradiated with the laser beam L. (See FIGS. 1 and 2).

From the portion of the stimulable phosphor sheet 10 irradiated with the laser beam L, a stimulable luminescence light of an amount corresponding to the radiation image information stored and recorded therein is emitted. The emitted photostimulated light M is diffused in all directions, a part of which is incident on the incident end face 54a of the light guide 54, and a part is reflected by the condenser mirror 58 and is incident on the incident end face 54a of the light guide 54. . The stimulated emission light M condensed on the light guide 54 in this way is PMT
The PMT 55 amplifies the stimulated emission light M, photoelectrically converts it into an image signal S, and outputs the image signal S to an external signal processing device.

Next, the operation in the cleaning mode for removing dust from the light collecting system will be described.

In the cleaning mode, the excitation light irradiation system and the image reading system do not operate, and only the transport function of the transport devices 21 and 22 operates. The transport devices 21 and 22 transport the cleaning sheet 110 in the direction of the arrow Y in the same manner as when transporting the stimulable phosphor sheet. As shown in FIGS. 3 (a) to 3 (f), the sheet conveying means 21 and 22 move the cleaning sheet 110 in the direction of the arrow Y so that the brush 112 on the sheet 110 is condensed with the condensing surface 58a and the condensing surface Incident end face of light guide 54
The entire surface of 54a is transported so as to be wiped in order. Thus, dust adhering to the surfaces 54a, 58a is easily removed.

The cleaning sheet 110 is shown in FIG.
If the transfer is performed in the Y direction to the position (f), and then the transfer is performed in the reverse direction (Y ′ direction in FIG. 1), the brush 112 wipes the surfaces 54a and 58a again. Is made more effective.

As described above, according to the dust removing method of the radiation image reading apparatus of the present embodiment, the dust adhering to the light condensing system can be easily removed, whereby the dust is accumulated and recorded on the stimulable phosphor sheet. Reading of the stimulating light emitted in accordance with the image information,
It is not necessary to disassemble and adjust the device for removing dust, so that the maintainability can be improved.

For example, in a radiation image reading apparatus (refer to Japanese Patent Application Laid-Open No. 4-280060, etc.) in which radiation image information is read separately from both surfaces of a stimulable phosphor sheet, the radiation image information is arranged on the sheet surface side. In addition to the light guide, the light guide is also placed on the back side of the sheet,
The cleaning sheet may have a cleaning brush formed on both sides of the sheet-like substrate.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a schematic configuration of a radiation image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a section taken along line II of FIG. 1;

FIG. 3 is a schematic view of a cleaning sheet used in the dust removal method of the present invention.

FIG. 4 is a diagram illustrating stepwise removal of dust in a light collecting system using a cleaning sheet.

[Explanation of symbols]

 54 Light guide 54a Incident end face of stimulated emission light 58 Condensing mirror 58a Condensing surface 110 Cleaning sheet 111 Sheet-like substrate 112 Brush

Claims (3)

[Claims] 1. A stimulable phosphor sheet on which radiation image information is accumulated and recorded is transported by a transport means, and the stimulable phosphor sheet is irradiated with excitation light to emit light emitted from the stimulable phosphor sheet. In a radiation image reading apparatus for reading out the radiation image information by condensing stimulated emission light by a light condensing system having an incident end face located close to the sheet, dust adhering to the incident end face is removed from the incident end face. A dust removing method for a radiation image reading apparatus, comprising: removing a dust attached to the incident end face by transporting a cleaning sheet having a cleaning brush on a surface by the transport unit. And a cleaning brush provided on the substrate for wiping the entire surface of the incident end surface when the substrate is transported by the transporting means. The cleaning sheet used in the dust removal method according to claim 1, wherein 3. The substrate has a width that is equal to or greater than the width of the stimulable phosphor sheet, and the cleaning brush has a softness that does not damage the incident end face; 3. The cleaning sheet according to claim 2, wherein the cleaning sheet is formed in a band shape in a width direction on the substrate.