JP2001066537A - Optical scanner - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely emit only a desired light beam toward an object to be scanned from the light beam emitting port of a casting housing at least a light beam scanning part. SOLUTION: The scanner is equipped with a light source part 16 emitting the laser beam L, a light beam scanning part 18 deflecting the laser beam L emitted from the light source part 16 and radiating it to the object to be scanned, the casing 70 housing the light beam scanning part 18 and a wedge- shaped glass window 88 which is disposed in the light beam emitting port 86 provided in the casing 70 and whose thickness differs from one end 90a to the other end 90b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical scanning device for recording or reading an image by irradiating a scanning object with a light beam emitted from a light source unit via a light beam scanning unit. .

[0002]

2. Description of the Related Art For example, stimulable phosphors (stimulable phosphors)
There is known a system that once records radiation image information of a subject such as a human body, reproduces the radiation image information on a photographic photosensitive material such as a photographic film, or outputs a visible image on a CRT or the like. I have.

The stimulable phosphor is composed of radiation (X-ray, α-ray, γ
(Rays, electron beams, ultraviolet rays, etc.), a part of this radiation energy is accumulated, and after irradiation with excitation light such as visible light, a phosphor that emits stimulated emission according to the accumulated energy is referred to. This stimulable phosphor is usually used as a stimulable phosphor sheet. In the above system, for example,
While transporting the stimulable phosphor sheet on which the radiation image information of the subject is once recorded in the sub-scanning direction, the excitation light is applied to the stimulable phosphor sheet in the main scanning direction (a direction substantially orthogonal to the sub-scanning direction). An optical scanning device that irradiates the radiation image information photoelectrically by irradiation is adopted.

Further, in the above-described system, in order to reproduce the radiation image information read from the stimulable phosphor sheet into, for example, a photographic film, the photographic film is conveyed in the sub-scanning direction while light is applied to the photographic film. An optical scanning device that irradiates a beam in the main scanning direction is employed.

[0005] This type of optical scanning device includes, for example, a light source 1 for emitting a light beam L and a light source 1 as shown in FIG.
And a light beam scanning unit 2 for deflecting the light beam L emitted from the light source and irradiating the light beam L to a scanning object (not shown). The light beam scanning unit 2 includes a polygon mirror 3, which is a rotating polygon mirror, an fθ lens 4, and a mirror 5 for deflecting the light beam L by approximately 90 °.

The light beam scanning section 2 is sealed in a casing 6 to prevent the flow of the atmosphere and to prevent dust and the like from adhering. A transparent glass window 8 is attached.

[0007]

However, in the above-described optical scanning device, a glass window 8 constituting a parallel flat plate is disposed on the optical path of the light beam L, and the light beam incident on the glass window 8 is provided. L may interfere in the glass window 8. As a result, a problem has been pointed out that the object to be scanned is irradiated with interference light, and high-quality image information reading processing and image recording processing are not performed.

SUMMARY OF THE INVENTION The present invention has been made to solve this kind of problem, and an optical scanning device capable of reliably preventing a light beam from interfering in a window member with a simple configuration and capable of performing high-quality scanning processing. The purpose is to provide.

[0009]

In the optical scanning device according to the present invention, a light beam scanning unit for deflecting a light beam emitted from a light source unit and irradiating the scanned object with the light beam is accommodated in a casing. A wedge-shaped light beam transmitting window member having a different thickness from one end to the other end is provided at the light beam exit port provided at. Therefore, there is no parallel plate in the optical path of the light beam, and it is possible to reliably prevent the light beam from interfering in the light beam transmitting window member.

Further, since the light beam transmitting window member is arranged to be inclined with respect to the optical path of the light beam, it is further ensured that the light beam reflected in the light beam transmitting window member is irradiated on the object to be scanned. Can be prevented.

Here, in the light beam transmitting window member, the outer surface of the light beam exit port is inclined downward and inside the light beam exit port. Therefore, in the light beam transmitting window member, the outer surface of the light beam exit port faces downward, and it is possible to effectively prevent dust and the like from adhering to this surface.

[0012]

FIG. 1 is a schematic structural explanatory view of an optical scanning device 10 according to an embodiment of the present invention.

The optical scanning device 10 sub-scans and conveys means 14 for sub-scanning and conveying a scanning object, for example, a stimulable phosphor sheet 12 in a vertically downward direction (the direction of arrow X), and a laser beam (light beam) L. The laser light L emitted from the light source unit 16 and the laser light L emitted from the light source unit 16 are deflected to make the laser light L
Is irradiated in the substantially horizontal direction (arrow Y direction), and a light beam scanning unit 18 that performs main scanning, and stimulable luminescent light emitted from the stimulable phosphor sheet 12 by irradiating the laser light L is collected. A reading unit 20 that photoelectrically reads the radiation image information carried on the stimulable phosphor sheet 12,
These are mounted on the unit base 22.

The sub-scanning and conveying means 14 includes a first and second roller pair 2 which are vertically spaced apart from each other by a predetermined distance.
4 and 26 are provided. First and second roller pairs 24, 26
Are synchronously driven to rotate via transmission means (not shown) connected to the motor 28.

As shown in FIG. 2 and FIG.
Includes a light source, for example, a semiconductor laser 32 disposed in a light source unit 30 mounted on the unit base 22. In the light source unit 30, a reflection mirror 34 for reflecting a laser beam L emitted downward from the semiconductor laser 32 in a manner inclined upward in the horizontal direction is incorporated, and a side portion of the light source unit 30 includes: The laser beam L reflected by the reflection mirror 34 is applied to the light beam scanning unit 18.
An opening 36 for guiding to the side is formed.

As shown in FIGS. 2 to 4, a light beam scanning unit 18 is incorporated in an optical unit 50. The light beam scanning unit 18 includes a polygon assembly 52 and a first
Lenses 54 and 56, a cylindrical lens 58, and a cylindrical mirror 60. The polygon assembly 52 has a polygon mirror 62 and a driver 64, and these are connected by a cable (not shown).

The optical unit 50 has a casing 70, which is detachably attached to the unit base 22 via mounting means 72. As shown in FIGS. 2 and 3, the mounting means 72 includes positioning pins 74a, 74b fixed to the unit base 22.
A notch 76 provided on one side of the casing 70 to engage with the positioning pin 74a; and a hole 78 formed on the other side of the casing 70 and into which the positioning pin 74b is inserted. And Casing 7
0, on both sides, a vertically long slot 80a-80d
Are formed, while the screw holes 82 are formed in the unit base 22.
a to 82d are provided, and the distal ends of the fixing pins 84 inserted into the elongated holes 80a to 80d are connected to the screw holes 82a to 82d.
By being screwed into d, the casing 70 is fixed to the unit base 22.

The casing 70 forms an optical surface plate 85 on which the polygon mirror 62, the first and second fθ lenses 54 and 56, the cylindrical lens 58, and the cylindrical mirror 60 are positioned and fixed. As shown in FIG. 4, a light beam exit 86 for emitting the laser beam L reflected by the cylindrical mirror 60 in a horizontal direction is formed in the casing 70, and the light beam exit 86 is provided with a light beam transmitting window. A glass window 88 as a member is mounted.

The glass window 88 is formed in a wedge shape having different thicknesses from one end 90a to the other end 90b.
Both surfaces 92a and 92b forming the wedge shape are set at 0.
In this embodiment, the angle is set to 1 ° or more and 1 °. The glass window 88 is disposed at a predetermined angle θ ° with respect to the optical path of the laser light L,
The outer surface 92b of the light beam exit 86 is inclined downward and inside the light beam exit 86.

As shown in FIG. 3, an opening 94 for guiding the laser beam L emitted from the light source section 16 to the polygon mirror 62 is formed in a side portion of the casing 70. A cover glass 96 is disposed. As shown in FIG. 2, after the polygon cover 98 is disposed on the polygon assembly 52, the casing 70
The optical unit cover 100 is fixed. A groove 102 is formed around the outer periphery of the casing 70, and the optical section cover 100 is pressed against a seal member 104 disposed in the groove 102 to keep the inside of the casing 70 lighttight.

As shown in FIG. 1, the reading section 20 includes a light-collecting guide 110 for collecting stimulated emission light emitted from the stimulable phosphor sheet 12 by irradiation with the laser light L. Is connected to a photomultiplier 112. A reflection mirror 114 that reflects stimulated emission light to the light-collecting guide 110 is disposed near the tip of the light-collecting guide 110.

The operation of the optical scanning device 10 thus configured will be described below.

The stimulable phosphor sheet 12 on which the radiation image information of the scanning object (not shown) is recorded,
And a pair of first and second rollers 2 which are vertically arranged and driven to rotate under the driving action of a motor 28 constituting
4 and 26, and are conveyed in the sub-scanning direction in the direction of arrow X (vertically downward).

At this time, as shown in FIG. 3, a laser beam L is emitted from a semiconductor laser 32 constituting the light source unit 16,
After the laser beam L once travels vertically downward, it is reflected by the reflection mirror 34 and from the opening 36 of the light source unit 30 to the cover glass 96 through the opening 94 of the casing 70.
Through. Further, the laser light L is transmitted to the polygon mirror 6.
2 and is deflected by the rotation of the polygon mirror 62. The laser light L passes through the first and second fθ lenses 54 and 56 and the cylindrical lens 58 and is irradiated on the cylindrical mirror 60, and is reflected by the cylindrical mirror 60 in the horizontal direction.

For this reason, the laser light L is transmitted through the glass window 88 and is led out of the light beam exit 86 in the direction of arrow Y, and as shown in FIG. The laser light L is applied to the photographing surface of the phosphor sheet 12.
Are irradiated in a substantially horizontal direction, and main scanning is performed.
By the irradiation of the laser beam L, photostimulated light is generated from the photographing surface of the stimulable phosphor sheet 12, and the photostimulated light is condensed via the condensing guide 110, and the photomultiplier 1
12 to read photoelectrically.

In this case, in this embodiment, as shown in FIG. 4, the glass window 88 provided at the light beam exit 86 of the casing 70 has a thickness from one end 90a toward the other end 90b. It is formed in a different wedge shape. For this reason,
The laser beam L reflected by the cylindrical mirror 60 is
When the light is applied to the glass window 88, the light does not become parallel to the laser beam L transmitted through the glass window 88 after being reflected in the glass window 88.

That is, it is possible to prevent the interference of the laser beam L within the glass window 88. Accordingly, the stimulable phosphor sheet 12 is not irradiated with the interference light, and the effect of reading the radiation image information recorded on the stimulable phosphor sheet 12 with high accuracy and reliability is ensured. can get.

The glass window 88 is arranged to be inclined by a predetermined angle θ ° with respect to the optical path of the laser light L. Therefore, unnecessary light (reflected light in the glass window 88) is not irradiated to the stimulable phosphor sheet 12 from between the reflection mirror 114 and the tip of the light collection guide 110. Moreover,
The outer surface 92b of the glass window 88 is inclined downward and inward, so that dust and the like can be effectively prevented from adhering to the surface 92b.

In this embodiment, the glass window 88 is used as the light beam transmitting window member. However, various materials, for example, resin materials, may be used as long as they can transmit the laser beam L effectively. You can also.

In the present embodiment, the work of attaching and detaching the optical unit 50 to and from the unit base 22 is performed with high precision and easily. That is, when attaching the optical unit 50 to the unit base 22, first, as shown in FIG. 5, a notch 76 formed at one end of the casing 70 is provided on the unit base 22. The positioning pin 74a is moved to the side of the positioning pin 74a, and the positioning pin 74a is engaged with the notch 76. Next, the positioning pins 74b fixed to the unit base 22 in the holes 78 formed in the other end of the casing 70 so that the optical unit 50 is arranged along the unit base 22 side.
Insert.

As a result, the optical unit 50 is positioned with respect to the unit base 22, and the fixing pins 84 are inserted into the slots 80 a to 80 d provided in the casing 70, and the respective tips are inserted into the unit base 22. It is screwed into the screw holes 82a to 82d provided. Therefore, the optical unit 50 can be positioned and fixed to the unit base 22, and there is an advantage that the positioning and fixing operation of the optical unit 50 can be performed smoothly and with high accuracy.

In this embodiment, the light beam scanning unit 1
Although the optical unit 50 incorporating the light source unit 8 and the light source unit 30 accommodating the light source unit 16 are separately configured, the optical unit 50 and the light source unit 30 may be integrally configured. In addition, although the description has been made using the stimulable phosphor sheet 12 as the object to be scanned, a similar effect can be obtained when an image is recorded on a photo film or the like.

[0033]

According to the optical scanning device of the present invention, a wedge-shaped light beam having a thickness varying from one end to the other end is provided at least to a light beam exit provided in a casing accommodating a light beam scanning unit. A transmission window member is provided, so that interference of light beams does not occur in the light beam transmission window member, and it is possible to reliably irradiate only a desired light beam to the object to be scanned. Accordingly, with a simple configuration, the image reading processing and the image recording processing can be performed on the scanned object with high accuracy and efficiency.

[Brief description of the drawings]

FIG. 1 is a schematic configuration explanatory view of an optical scanning device according to an embodiment of the present invention.

FIG. 2 is an exploded perspective view illustrating a light source unit and a light beam scanning unit that constitute the optical scanning device.

FIG. 3 is an explanatory plan view of the light source unit and the light beam scanning unit.

FIG. 4 is an explanatory longitudinal sectional view of the light beam scanning unit.

FIG. 5 is an operation explanatory diagram when the optical unit accommodating the light beam scanning unit is mounted on a unit base.

FIG. 6 is a schematic perspective explanatory view of an optical scanning device according to a conventional technique.

[Explanation of symbols]

Reference Signs List 10 optical scanning device 12 stimulable phosphor sheet 14 sub-scanning conveyance means 16 light source unit 18 light beam scanning unit 20 reading unit 22 unit base 30 light source unit 32 semiconductor laser 34, 114 reflection Mirror 50 optical unit 52 polygon assembly 54, 56 fθ lens 58 cylindrical lens 60 cylindrical mirror 62 polygon mirror 70 casing 72 mounting means 74a, 74b positioning pin 76 cutout 78 hole 85 ... Optical surface plate 86 ... Light beam emission port 88 ... Glass window 90a ... One end 90b ... Other end 92a, 92b ... Surface 110 ... Condensing guide

Claims (3)

[Claims] A light source section for emitting a light beam; a light beam scanning section for deflecting the light beam emitted from the light source section to irradiate a scanned object; and a casing accommodating at least the light beam scanning section. And a wedge-shaped light beam transmitting window member, which is provided at a light beam emission port provided in the casing and has a different thickness from one end to the other end. 2. An optical scanning device according to claim 1, wherein said light beam transmitting window member is arranged obliquely with respect to an optical path of said light beam. 3. The optical scanning device according to claim 1, wherein the light beam transmitting window member has a surface outside the light beam exit port inclined downward and inside the light beam exit port. An optical scanning device characterized by the above-mentioned.