JP2001215377A - Holder for optical member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent flatness from being impaired in an optical member without making adjustment with high precision, in positioning and assembling a planar optical member with three steel balls. SOLUTION: An optical filter 152 arranged in the opening 156 of a holder body 154 is positioned by bringing three steel balls 158 into contact with one surface. In addition, the optical filter is such that the boss parts 188 of a holding plate 168 arranged on the other surface come into planar contact with a prescribed area including contact points S of the steel balls. The holding plate, pressed by leaf springs 178-182, holds the optical filter between the plate and the steel balls. In this case, since the boss parts are each in planar contact with the optical filter in the prescribed area including the contact points S with the steel balls, the optical filter is parallelly pressurized toward the steel balls, positioned and held, with the flatness unimpaired.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical member holder to which a flat optical member such as a mirror or a filter is mounted.

[0002]

2. Description of the Related Art In an image exposure apparatus for exposing a photosensitive material such as a photosensitive lithographic printing plate (hereinafter, referred to as a "printing plate") used for printing or the like, a semiconductor laser or an LED is used as a light source. The printing plate is exposed by a light beam. At this time, by modulating the light beam based on the image data, an image corresponding to the image data is formed on the printing plate.

An optical system provided in such an image exposure apparatus irradiates a printing plate with a light beam emitted from, for example, a laser diode as a light source using various lenses and filters. Generally, filters and the like used in such an optical system are formed in a thin plate shape.

In order to properly diffract and polarize a light beam, it is necessary to maintain the planarity of optical members such as filters forming an optical system and to arrange these optical members at appropriate positions and angles. There is. For this reason, in a holder in which an optical member is previously assembled, when the optical system is formed, the optical member is positioned and assembled so that the position and angle of the optical member with respect to the light beam are appropriate.

[0005] For example, a holder 200 shown in FIG.
In this case, three spherical bodies 204A facing one surface of the filter 202 and a spherical body 204B facing the other surface of the contact point of each spherical body 204A are used.
The filter 202 is sandwiched between A and 204B. At this time,
For example, by attaching the sphere 204B to the leaf spring 206 to urge the steel ball 204B toward the filter 202, the filter 2 is placed between the steel balls 204A and 204B.
02 is pinched and held.

In such a holder 200, the filter 2
02, two spheres 204A are arranged in opposition to one surface of the filter 202, and a plane including a contact point where each of the three steel balls 204A is in contact with the filter 202 has a predetermined plane with respect to the optical axis of the light beam. Steel ball 204A so as to form an angle (for example, a right angle).
Is installed.

As a result, in the holder 200, the filter 2
The filter 202 sandwiched by the steel balls 204A and 204B is positioned so as to be at a predetermined angle with respect to the optical axis while preventing distortion of the filter 202 caused when substantially the entire surface of the filter 02 is suppressed. FIG.
(A) illustrates two of the three spherical bodies 204A and 204B.

[0008]

However, when the thin plate-shaped optical member such as the filter 202 is sandwiched and held between the opposed steel balls 204A and 204B on both sides thereof, the opposed steel balls 204A and 204B are accurately placed. Need to position. That is, as shown by a solid line in FIG. 8B, if the position of steel ball 204A in contact with one surface of filter 202 matches the position of steel ball 204B facing the other surface, the plane of filter 202 Sex is maintained.
However, as shown by a two-dot chain line in FIG. 8B, for example, when a position shift occurs between the steel balls 204A and 204B facing each other, the filter 202 is curved or the like, and the flatness of the filter 202 is reduced. Will be spoiled.

Therefore, when a steel ball or the like facing one surface of an optical member such as a filter is positioned and held by three points of contact using a steel ball or the like, in order to prevent distortion or bending of the optical member. Requires high-precision positioning of steel balls, etc., which are arranged to face each other so as to sandwich the optical member, and in particular, the work of mounting the optical member, which has high flexibility such as a filter and is likely to bend or deform, is complicated. I have.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described circumstances, and it is an object of the present invention to provide an optical member holder to which a flat optical member such as a filter can be easily attached without performing high-precision positioning. Aim.

[0011]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides an optical member holder to which a flat optical member is attached, wherein the holder main body holds the optical member, Three point support members which are arranged at predetermined positions facing one surface of the optical member, and which are positioned by contacting the three members, and which are arranged facing the other surface of the optical member; And a surface support member that is in surface contact with a predetermined region of the optical member facing each of the point support members and sandwiches the optical member between the point support members.

According to the present invention, the predetermined 3
The optical members are positioned with respect to the holder body by providing the point support members at the locations and arranging the point support members such that one surface of the flat optical member is in contact with each point support member. Further, a surface support member is arranged to face the point support member, and the optical member is held between the surface support member and the point support member.

When the optical member is sandwiched between each of the point supporting members and the surface supporting member, the point supporting member comes into contact with the optical member in a region where the surface supporting member is in surface contact with the optical member, and By pressing parallel to the contact surface of the support member,
The flat optical member can be held without causing bending or the like.

As described above, when the point support member is brought into contact with one surface of the optical member and positioned and held, the surface support member is brought into contact with a predetermined region of the other surface, thereby simplifying the operation. The optical member can be attached to the holder body by performing highly accurate positioning. That is, when the point support members are brought into contact with both surfaces of the optical member, it is necessary to perform accurate positioning between the point support members. However, the use of the surface support members eliminates the need for accurate positioning. The attachment of the member to the holder body is facilitated.

According to the present invention, a sphere provided at a predetermined position of the holder body can be used as the point support member.

According to the present invention, the surface supporting member is provided with a pressing plate opposed to each of the point supporting members, and an urging member attached to the holder body for urging the pressing plate toward the point supporting member. Means.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a schematic configuration of an image exposure apparatus 10 applied to the present embodiment. The image exposure apparatus 10 has a rectangular thin plate shape (for example, having a thickness of 0.3 mm) formed of aluminum or the like as an example of a sheet body.
), And a photosensitive lithographic printing plate (hereinafter, referred to as “printing plate 12”) having a photosensitive layer formed on the support is irradiated with a light beam modulated based on image data to perform scanning exposure. Printing plate 1 after image exposure by image exposure device 10
2 is subjected to development processing or the like by an automatic developing device or the like (not shown).

As shown in FIG. 1, an image exposure apparatus 10
The cassette loading unit 18 and the plate feeding / conveying unit 2
0, a recording unit 22, a discharge buffer unit 24, and the like. The cassette loading unit 18 is disposed in the machine frame 14 at the lower right side in FIG.
Are loaded in a state where the cassettes 16 are inclined at a predetermined angle.

The image exposure apparatus 10 can process a plurality of sizes of printing plates 12 having different vertical or horizontal dimensions. On the upper side, one end is positioned and accommodated so as to be at a predetermined position. The cassette loading section 18 has printing plates 12 of different sizes.
Are loaded at predetermined intervals so that one end of the printing plate 12 accommodated therein has a substantially constant height.

The plate feeding section 20 is arranged above the cassette loading section 18, and the recording section 22 is arranged at the lower center of the apparatus adjacent to the cassette loading section 18. A reversing unit 28 and a single-wafer unit 30 are attached to a pair of side plates 26 (only one is shown in FIG. 1) of the plate feeder 20.

The reversing unit 28 includes a reversing roller 32 having a predetermined outer diameter, and a plurality of small rollers 34 (in the present embodiment, as an example, the small rollers 34A, 34B, 34C, 34D) around the reversing roller 32. 4) are provided. The small rollers 34A to 34D are connected to the cassette loading unit 1
An endless conveyance belt 36 is disposed around the recording unit 22 from the side of the recording roller 22 through the upper side of the reversing roller 32 from the side 8. Thus, the small roller 34 is attached to the reversing roller 32.
A and the conveying belt 3 over about half the circumference between the small rollers 34D.
6 is wound.

On the other hand, the single wafer unit 30 includes the cassette 16
A plurality of suction cups 38 for adsorbing the upper end of the printing plate 12 in the inside are provided. By moving the suction cup 38 downward, the suction plate 38 is opposed to the upper end of the printing plate 12 in the cassette 16 loaded in the cassette loading section 18. The suction plate 38 sucks the printing plate 12. In addition, the sheet-fed unit 30 includes the printing plate 1
The printing plate 12 is pulled out from the cassette 16 by moving the suction cup 38 having sucked 2 substantially upward, and the leading end of the drawn printing plate 12 is inserted between the reversing roller 32 and the transport belt 36. In FIG. 1, the outline of the moving position of the suction cup 38 is indicated by a two-dot chain line.

In the reversing unit 28, the reversing roller 32 and the transport belt 36 rotate in the direction of pulling out the printing plate 12 from the cassette 16 (the direction of arrow A in FIG. 1). Printing plate 12
When the leading end is nipped between the reversing roller 32 and the transport belt 36, the reversing roller 3
It is wound around the circumference of 2. Thereby, the printing plate 12
Is conveyed while being curved and inverted, and the conveying direction is turned. Note that the radius of the reversing roller 32 is a dimension (for example, 100 mm or more) that does not cause the printing plate 12 to bend or bend when the printing plate 12 is curved.

As shown by the solid line and the two-dot chain line in FIG. 1, the side plate 26 moves horizontally according to the position of the cassette 16 from which the printing plate 12 is taken out. Thereby, the single wafer unit 30
The suction cup 38 can be horizontally moved integrally with the reversing unit 28 so as to face the printing plate 12 in a desired cassette 16.

The side plate 26 is provided with a guide 40 below the small roller 34D. The printing plate 12 inverted by the reversing roller 32 moves between the reversing roller 32 and the transport belt 36 on the small roller 34D side. From this guide 40
Sent out to.

Above the recording section 22, a conveyor 42 is provided.
Are arranged, and the printing plate 12 sent out from the reversing unit 28 is guided by the guide 40 to the transport conveyor 42. The guide 40 swings with the movement of the side plate 26 so that the guide direction of the printing plate 12 is always directed to the conveyor 42. Further, the small roller 34D of the recording unit 22 moves so as to change the sending direction of the printing plate 12 from the reversing unit 28 with the movement of the side plate 26, and the small roller 34C moves when the small roller 34D moves. The printing plate 12 sent from the reversing unit 28 moves so as to apply a substantially constant tension to
The curve is gently curved by 0.

In the transport conveyor 42, a transport belt 48 is wound around a roller 44 disposed substantially below the guide 40 and a roller 46 disposed above the recording unit 22, and the roller 46 side faces downward. So that it is inclined.

As shown in FIGS. 1 and 2, a roller 50 is arranged on the conveyor 42 so as to face the roller 46. The printing plate 12 sent onto the conveyor 42 is conveyed on a conveyor belt 48 and is supplied with rollers 46, 5.
0 and is sent out from the conveyor 42.

In the recording section 22, a rotary drum 54 is disposed on a gantry 52, and a recording head section 56 is disposed to face the rotary drum 54. In addition, the image exposure apparatus 10 has a pair of rollers 46 and 50 of the conveyor 42,
A puncher 58 is provided above the recording unit 22 (rotary drum 54).
Is provided.

As shown in FIG. 2, the mouthpiece 60 is formed in the puncher 58,
Is to hold the printing plate 12 between the rollers 46 and 50 and insert the leading end into the mouth opening 60 of the puncher 58 to hold it.
The puncher 58 holds the printing plate 12 inserted in the mouthpiece 60.
For example, a notch is formed at a predetermined position at the tip of the head for positioning. For example, the printing plate 12 is positioned on the conveyor 42 and sent to the puncher 58, so that a notch for positioning is formed at a predetermined position at the leading end.

When the notch is formed in the printing plate 12, the conveyor 42 drives the conveyor belt 48 in the reverse direction to pull out the leading end of the printing plate 12 from the opening 60 of the puncher 58. The transport conveyor 42 can swing about the roller 44 by swinging means (not shown), and swings when the printing plate 12 is pulled out from the puncher 58 (shown by a two-dot chain line in FIGS. 1 and 2). Then, after the leading end of the printing plate 12 is directed to a predetermined position on the outer peripheral surface of the rotary drum 54, the printing plate 12 is sent out toward the recording unit 22.

The rotating drum 54 provided in the recording section 22
The printing plate 12 is driven by a driving force of a driving unit (not shown).
In the mounting exposure direction (the direction of the arrow B in FIGS. 1 and 2) and the direction of removing the printing plate 12 opposite to the mounting exposure direction (the direction of the arrow C in FIGS. 1 and 2). Driven.

As shown in FIG. 2, the rotary drum 54 is provided with a tip chuck 62 at a predetermined position on the outer peripheral surface. In the recording unit 22, when the printing plate 12 is mounted on the rotary drum 54, first, the tip chuck 62
At a position (printing plate mounting position) opposed to the leading end of the printing plate 12 fed by the conveyor 42, the rotating drum 54 is
To stop.

The recording section 22 is provided with a mounting cam 64 facing the front end chuck 62 at the printing plate mounting position.
The printing plate 12 can be inserted between the tip chuck 62 and the peripheral surface of the rotating drum 54 when one end side thereof is pressed by the rotation of the mounting cam 64. In the recording unit 22, the mounting cam 64 is returned in a state where the leading end of the printing plate 12 is inserted between the leading end chuck 62 and the rotating drum 54, and the pressing on the leading end chuck 62 is released. Is held between the front end chuck 62 and the peripheral surface of the rotating drum 54.

In the image exposure apparatus 10, the printing plate 12
The printing plate 12 is positioned with respect to the rotary drum 54 by inserting a pin (not shown) projecting at a predetermined position on the peripheral surface of the rotary drum 54 into a notch formed at the tip of the printing drum 12.

A squeeze roller 66 is arranged around the rotary drum 54 downstream of the printing plate mounting position in the mounting exposure direction. The squeeze roller 66 moves toward the rotating drum 54 and presses the printing plate 12 wound around the rotating drum 54 toward the rotating drum 54, thereby bringing the printing plate 12 into close contact with the peripheral surface of the rotating drum 54.

The recording unit 22 includes a squeeze roller 6.
A rear end chuck attaching / detaching unit 68 is provided upstream of the rotary drum 54 in the mounting exposure direction with respect to 6, and a removal cam 70 is disposed downstream in the mounting exposure direction. In the rear end chuck attaching / detaching unit 68, a rear end chuck 74 is detachably provided at a front end of a shaft 72 protruding toward the rotating drum 54.

In the recording unit 22, the rear end of the printing plate 12 wound around the rotary drum 54 is connected to the rear end chuck attaching / detaching unit 6.
When reaching the rear end chuck attaching / detaching position opposed to 8, the rotation of the rotary drum 54 is temporarily stopped, and the rear end chuck 74 is mounted on a predetermined position of the rotary drum 54. As a result, the printing plate 12 wound around the rotating drum 54 is fixed with the trailing end held between the rotating drum 54 and the trailing end chuck 74.

A suction groove (not shown) for sucking and holding the printing plate 12 wound around the rotating drum 54 is formed on the outer peripheral surface of the rotating drum 54. The rear end and the rear end are fixed by the front end chuck 62 and the rear end chuck 74, respectively, and are sucked by the negative pressure supplied to the suction groove so as to be brought into close contact with the peripheral surface of the rotating drum 54.

In the recording section 22, when the printing plate 12 is positioned and wound on the rotary drum 54, the squeeze roller 66 is separated, and the rotary drum 54 is rotated at a predetermined rotational speed at a high speed. Synchronously, a light beam modulated based on the image data is emitted from the recording head unit 56. As a result, the printing plate 12 is scanned and exposed based on the image data, and an image is formed at a predetermined position.

In the recording section 22, when the scanning exposure to the printing plate 12 is completed, the rotating drum 54 is stopped at the rear end chuck attaching / detaching position, and the rotating drum 5 is rotated by the squeeze roller 66.
4 while holding the printing plate 12 therebetween.
Then, the trailing end chuck 74 is removed from the printing plate 4 to open the trailing end of the printing plate 12.

In the recording section 22, when the rear end chuck 74 is removed from the rotating drum 54, the rotating drum 54 is
2. Rotate in the unloading direction. Thereby, the printing plate 12 is sent out from between the squeeze roller 66 and the rotating drum 54.

As shown in FIG. 1, the discharge buffer unit 2
4 is provided above the recording unit 22, and the rotating drum 54 rotates in the direction in which the printing plate 12 is removed,
The printing plate 12 is sent out from the rear end side to the discharge buffer unit 24. In the recording unit 22, the rotating drum 54
When the front end chuck 62 reaches the printing plate removal position facing the removal cam 70 when is rotated in the removal direction of the printing plate 12, the rotating drum 54 is stopped, and the removal cam 70 is rotated at this position. Thereby, the tip chuck 62
The holding of the leading end of the printing plate 12 between the printing plate 12 and the rotating drum 54 is released, and the printing plate 12 is removed from the rotating drum 54.

On the other hand, the discharge buffer section 24 is provided inside a discharge port 76 formed in the machine casing 14.
A discharge roller 78 is provided. Around the discharge roller 78, a plurality of small rollers (for example, small rollers 80A,
80B, 80C, 80D, and 80E), and an endless transport belt 82 is wound between these small rollers 80A to 80E. Thus, the transport belt 82 is wound around the discharge roller 78 in a range of １ ／ to ／ of the circumference between the small rollers 80A and 80E.

The small roller 80A is provided so as to protrude toward the squeeze roller 66 of the recording unit 22. The roller 84 is disposed to face the small roller 80A. Is guided and pinched between the rollers 84.

In the discharge buffer section 24, the discharge rollers 78
Is rotated in the direction in which the printing plate 12 is pulled in (in the direction of arrow D), so that the printing plate 12 sandwiched between the small rollers 80A and the rollers 84 is guided between the discharge roller 78 and the transport belt 82 while being pulled out from the recording unit 22. , Discharge roller 78
, And wound around the discharge roller 78. At this time, in the discharge buffer unit 24, the discharge roller 78 is stopped while the leading end of the printing plate 12 (the rear end side when sent from the recording unit 22) is sandwiched between the small rollers 80A and the rollers 84, and the discharge roller 78 is stopped. Printing plate 1 wrapped around 78
2 is temporarily held.

As shown by a two-dot chain line in FIG. 1, in the discharge buffer section 24, the small roller 80A and the roller 84 move to a position facing the discharge port 76. At this time, the small roller 80A and the roller 84 move integrally, so that the leading end of the printing plate 12 is directed to the discharge port 76. The small roller 80B above the small roller 80A moves so as to apply a constant tension to the transport belt 82 following the movement of the small roller 80A.

In the discharge buffer section 24, when the leading end of the printing plate 12 is directed to the discharge port 76, the discharge roller 78 is moved to the printing plate 12 by a processing device such as an automatic developing device arranged adjacent to the discharge port 76. The printing plate 12 is driven to rotate at a rotation speed corresponding to the conveyance speed of the printing plate 12 in the direction in which the printing plate 12 is sent out (the direction opposite to the direction of arrow D). As a result, the printing plate 12 is sent out from the outlet 76.

The image exposure apparatus 1 thus formed
At 0, image data to be exposed on the printing plate 12 is input,
When the size, the number of exposures, and the like of the printing plate 12 on which image exposure is performed are set and the start of image exposure is instructed,
To start the image exposure processing. Note that these processes are
An operation panel may be provided in the image exposure apparatus 10, and an instruction may be given by operating a switch on the operation panel.
The processing of the image exposure apparatus 10 may be instructed by a signal from an image processing apparatus or the like that outputs image data to the image exposure apparatus 10.

In the image exposure apparatus 10, when the start of the processing is instructed, the printing plate 12 of the designated size is placed in the cassette 1
6 and placed on the conveyor 42 and supplied to the recording unit 22. At this time, the printing plate 12 includes the puncher 5
8, a notch for positioning is formed.

In the recording unit 22, when the leading end of the printing plate 12 is held on the rotating drum 54 by the tip chuck 62, the printing plate 12 is wound around the rotating drum 54 while being squeezed by the squeeze roller 66, and the rear end of the printing plate 12 is Is held on the rotating drum 54 by the rear end chuck 74.

Thereafter, in the recording section 22, the rotating drum 54
The recording plate 56 irradiates the printing plate 12 with a light beam based on image data while rotating the printing plate 12 at a high speed.
Is scanned and exposed, and a predetermined area of the printing plate 12 is scanned and exposed to form an image.

When an image is formed, the printing plate 12 is sent from the rear end side to the discharge buffer unit 24 while being removed from the rotating drum 54. In the discharge buffer unit 24, once the printing plate 12 is wound around the discharge roller 78, the tip of the printing plate 12 is directed to the discharge port 76, and the discharge roller 78 is driven to rotate in the reverse direction. Thus, the printing plate 12 is sent out from the outlet 76 at a predetermined transport speed, and is discharged from the image exposure device 10.

The recording unit 22 of the image exposure apparatus 10
As shown in FIG. 3, a sub-scanning device 102 is provided in the recording head unit 56. This sub-scanning device 102
Includes a light source unit 100.

The sub-scanning device 102 has a stage 106 provided on a base 104. The stage 106 has legs 106A on the side of the rotating drum 54 (right side in FIG. 3) and on the side opposite to the rotating drum 54.
And the base 104 are connected by a leaf spring 108. Thus, the stage 106 is supported on the base 104, and is movable in the direction of contacting and separating with the rotary drum 54 (the horizontal direction in FIG. 3) by the elastic deformation of the leaf spring 108. .

The base 104 has a stepping motor 11
The worm gear 112 is supported below the stage 106. Stepping motor 1
In 10, the drive shaft 110 </ b> A is connected to the worm gear 112, and the worm gear 112 is rotated by the operation of the stepping motor 110.

The base 104 is provided with a worm wheel 114 and an eccentric cam 116 between the legs 106A of the stage 106. The worm wheel 114 is
The worm gear 112 meshes with the worm gear 112, and the worm wheel 114 rotates integrally with the eccentric cam 116 by transmitting the rotational force of the worm gear 112.

The eccentric cam 116 has an outer peripheral portion formed by one of the leg portions 106A of the stage 106 by the urging force of the leaf spring 108.
, And rotates eccentrically with respect to the worm wheel 114. As a result, when the worm wheel 114 rotates, the eccentric cam 116 presses the leg 116A of the stage 106, and moves the stage 106 toward and away from the rotary drum 54 against the urging force of the leaf spring 108 (see FIG. 3). (Left / right direction).

In the sub-scanning device 102, the eccentric cam 11
6, the light source unit 100 provided on the stage 106 is moved in the direction in which the light source unit 100 comes into contact with and separates from the rotary drum 54, so that the distance between the light source unit 100 and the rotary drum 54,
The spot adjustment (focus adjustment) of the light beam applied to the printing plate 12 wound on the printing plate 12 can be performed. Note that the sub-scanning device 102 includes a stepping motor 11 at both ends along the axial direction of the rotating drum 54 (the front and back directions in FIG. 3).
0, a worm gear 112, a worm wheel 114, and an eccentric cam 116 are provided so that the inclination with respect to the axis of the rotating drum 54 is adjusted in advance.

The sub-scanning device 102 moves the base 104 in the sub-scanning direction (the axial direction of the rotary drum 54, the front and back of FIG. 3) by sub-scanning driving means (not shown).

A plurality of light source units 100 are provided on the stage 106 of the sub-scanning device 102. Each light source unit 100 is arranged at a predetermined interval along the axial direction of the rotating drum 54. In the sub-scanning device 102, the plurality of light source units 100 are integrally moved in the sub-scanning direction by moving the base 104 in the sub-scanning direction.

Thus, the recording unit 22 scans and exposes the printing plate 12 by moving each light beam in the sub-scanning direction while irradiating a plurality of light beams from the recording head unit 56. . The sub-scanning device 102
Use the same light source unit 100. In the present embodiment, one light source unit 100 will be described with reference to the drawings.

As shown in FIGS. 3 and 4, the light source unit 100 has a base 118. The base 118 includes a base 120 facing the stage 106 and an upright wall 12 vertically erected from one end of the base 120.
2 form a substantially L-shape. As shown in FIG. 3, the light source unit 100 has the base 120 mounted and fixed at a predetermined position on the stage 106.

As shown in FIGS. 3 and 4, the light source unit 100 includes a light source assembly 124 on the upright wall 122.
Is mounted, and the optical system assembly 12 is mounted on the base 120.
6 is attached.

The light source assembly 124 includes the light source holder 1
28 and 130, and is attached via a base plate 132 to the surface of the upright wall 122 opposite to the rotary drum 54 (the left side in FIG. 3 and the back side in FIG. 4). In the light source assembly 124, for example, a laser diode (Laser Diode), which is one of semiconductor light emitting elements, is incorporated between the light source holders 128 and 130 as a light emitting element serving as a light source. A lens is attached (both are not shown). The distance between the laser diode and the collimator lens is adjusted in advance, and the laser diode and the collimator lens are attached to predetermined positions of the light source unit 100 by assembling the light source assembly 124 to the upright wall 122.

Further, the rotating drum 54 is
A parallel plate holder 134 having a parallel plate (not shown) provided on the side surface is attached, and the light beam passes through the parallel plate in the parallel plate holder 134 and is emitted toward the optical system assembly 126. Is done.

The optical system assembly 126 has a long fixed base 136. A condenser lens holder 138 having a condenser lens attached to one end in the longitudinal direction is attached to the fixed base 136, and a convex cylindrical lens is attached in order from the condenser lens holder 138. Cylindrical lens holder 140, uniaxial crystal holder 1 with uniaxial crystal attached
42, a cylindrical lens holder 144 to which a concave cylindrical lens is attached, a parallel plate holder 146 to which a parallel plate is attached, an aperture holder 148 to which an aperture is attached, and a convex cylindrical lens. Holders 150 to which the half-wave plate is attached are arranged in order. The uniaxial crystal holder 142 is attached to a cylindrical lens holder 144.

The optical system assembly 126 is arranged such that the condenser lens holder 138 is on the rotating drum 54 side (the side opposite to the upright wall 122), and the fixing base 136 is mounted on the base 1.
Attached to the arrangement at the base 120 of the 18. Thus, the light beam emitted from the light source assembly 124 is converted into a parallel plate, a half-wave plate, a cylindrical lens, an aperture, a parallel plate, a cylindrical lens, a uniaxial crystal, a cylindrical lens, and a condenser lens. And irradiates the printing plate 12.

On the other hand, a cylindrical lens (not shown) is attached to the holder 150 on the aperture holder 148 side. Also, as shown in FIGS. 5 and 6,
A half-wave plate (hereinafter referred to as “optical filter 152”), which is a flat optical member, is provided on the holder 150 on the light source assembly 124 side (the surface on the near side of FIG. 5 and the upper surface of FIG. 6).
Is attached).

That is, in the present embodiment, the optical filter 152 is used as a plate-shaped optical member applied to the present invention, and the light source assembly 124 side of the holder 150 to which the optical filter 152 is attached is an optical filter to which the present invention is applied. It is a holder main body 154 of the member holder. In the following, the light source assembly 124 side of the holder 150 will be described as the holder body 154, and illustration and description of the cylindrical lens will be omitted.

The holder main body 154 has a rectangular opening 156 for accommodating the optical filter 152 at the center. In the opening 156, holding portions 160, 162, and 164 for accommodating steel balls 158 serving as point support members are protruded from the peripheral edge.

The holders 160 and 162 are connected to the holder body 15
The holder 164 protrudes into the opening 156 from the other end of the holder main body 154. Further, the holding unit 160,
162, a receiving hole 166 is formed at the center of the surface on the side of the light source assembly 124, and the holding portion 164 is provided at an intermediate portion of the surface on the side of the light source assembly 124 in the vertical direction.
6 are formed. The steel balls 158 are attached to the holding portions 160, 1
62 and 164 are accommodated in the accommodation holes 166.

As shown in FIG. 6, the steel ball 158 has an outer peripheral portion projecting from the accommodation hole 166. In addition, each steel ball 1 protruding from the inside of the accommodation hole 166.
When one surface of the optical filter 152 abuts on 58, the optical filter 152 is positioned with respect to the light beam emitted from the light source assembly 124. That is, the optical filter 152 is positioned with respect to the holder main body 154 by being held in a state where one surface thereof is in contact with the three steel balls 158.

On the other hand, as shown in FIGS. 5 and 6, a holding plate 168 is attached to the holder body 154 in the opening 156. The holding plate 168 is arranged so as to cover the optical filter 152 housed in the opening 156. In addition, the holding plate 168 is made of a metal such as aluminum or stainless steel, which hardly bends compared to the optical filter 152,
It is formed in a thin plate shape by a material having high rigidity.

The pressing plate 168 has a peripheral portion that is
0, 162, and 164 respectively. In addition, holding plate 1
68, a substantially rectangular opening is formed at the center, and the light beam passes through the opening of the holding plate 168,
The light is applied to the optical filter 152.

As shown in FIG. 5, the holding plate 168
Has a rectangular cutout 168A at one end. In addition, a holder 170 is attached to the holder main body 154 at the periphery of the opening 156.

The holding member 170 is formed in a substantially L-shape, and a screw hole 172 inserted into a mounting hole 170A formed at one end portion is formed at a predetermined position of the holder main body 154 by a screw hole. 174 is attached to the holder main body 154 by screwing. In addition, holding bracket 170
When mounted on the holder main body 154, the other end enters the opening 156, contacts the end face of the optical filter 152, and presses the optical filter 152 toward the peripheral edge on the other end of the opening 156. I do.

Thus, the optical filter 152 is fixed by being sandwiched between the holding member 170 and the inner surface of the opening 156 of the holder main body 154. At this time, the notch 168A is provided so that the pressing plate 168 does not interfere with the holding member 170.
Are formed.

A plurality of screw holes 176 are formed in the holder main body 154 at predetermined positions on the periphery of the opening 156. The screw holes 176 are provided in the holding members 160, 162, 164.
Are formed adjacent to each other.

Further, leaf springs 178, 180, and 182 are attached to the holder body 154 as urging means.
Each of the leaf springs 178, 180, and 182 has a fixed portion 184 formed by widening one end side in the longitudinal direction.
The fixing screw 186 inserted into the mounting hole 184A of the fixing portion 184 is screwed into the screw hole 176, so that it is mounted on the holder main body 154.

As shown in FIGS. 5 to 7, the leaf spring 1
78, 180, and 182 have the other end bent toward the holding plate 168. Thereby, the leaf springs 178, 18
When the fixing portion 184 is fixed to the holder main body 154, the ends of the fixing members 184 abut against the pressing plate 168, and press the pressing plate 168 toward the steel ball 158.

On the other hand, a boss 188 is formed on the pressing plate 168 so as to face each of the steel balls 158. As shown in FIG. 7, each of the boss portions 188 is formed such that the surface facing the optical filter 152 is a flat surface, and protrudes from the holding plate 168. Further, the holding plate 168 is provided such that the planes of the three boss portions 188 are the same.

The pressing plate 168 is configured so that the vicinity of the boss 188 is pressed by each of the leaf springs 178, 180, and 182, and the boss 188 of the pressing plate 168 comes into surface contact with the optical filter 152. The optical filter 152 is pressed. At this time, since the boss portion 188 is flat, the boss portion 188 is
Optical filter 15 including a contact point S (see FIG. 6) to 52
2 is uniformly pressed.

As a result, the optical filter 152 is held between the steel ball 158 and the boss 188 of the holding plate 168 and is held by the holder body 154.

The recording unit 2 provided with the light source unit 100 to which the holder 150 thus formed is attached.
In 2, the rotating drum 54 around which the printing plate 12 is wound is rotated in the main scanning direction (printing plate mounting exposure direction), and the light source is synchronized with the rotation of the rotating drum 54 and the movement of the stage 106 in the sub-scanning direction. A light beam corresponding to the image data is emitted from the assembly 124.

The light beam emitted from the light source assembly 124 passes through the optical filter 152, which is a half-wave plate, and then has a convex cylindrical lens, an aperture, a parallel plate, a concave cylindrical lens, and a uniaxial lens. The light passes through the crystalline material, the convex cylindrical lens, and the condenser lens, and is irradiated on the printing plate 12 wound around the rotating drum 54. Thereby, the printing plate 12 is exposed to an image corresponding to the image data.

The light source unit 100 is formed by a light source assembly 124 attached to a base 118 and an optical system assembly 126. The optical system assembly 126 includes a condenser lens holder 138, a cylindrical lens holder 140, and a position axis crystal body holder 1.
42, the cylindrical lens holder 144, the parallel plate holder 146, the aperture holder 148, and the holder 15
0 is attached. An optical filter 152 is attached to the holder 150 at a predetermined position of the holder main body 154.

The holder main body 154 has steel balls 158 attached to holding portions 160, 162 and 164 provided in the opening 156.
When the optical filter 152 is attached to the holder main body 154, the optical filter 152 is arranged in the opening 156 of the holder main body 154. As a result, the three steel balls 158 provided in the holding portions 160, 162, and 164 in the opening 156 abut on one surface of the optical filter 152.

After that, the optical filter 152 is fixed in the opening 156 of the holder main body 154 by the holding member 170, and the holding plate 168 is covered so as to cover the optical filter 152.
Place. As a result, the boss portions 188 formed on each of the pressing plates 168 are in surface contact with the other surface of the optical filter 152 (the surface opposite to the steel ball 158 abutting), and the optical filter 152 , Steel ball 158 and holding plate 1
68 boss portions 188.

After arranging the optical filter 152 and the holding plate 168 in the opening 156 of the holder main body 154 in this manner, the plate springs 178, 180, 182 are mounted on the holder main body 154.
Attach.

The leaf springs 178, 180, 182 press the boss 188 of the holding plate 168 facing the steel ball 158 when the fixing portion 184 is attached to the holder main body 154. As a result, the holding plate 168 is pressed toward the optical filter 152, and the optical filter
2 is held by the holder body 154 while being sandwiched between the steel ball 158 and the boss 188 of the holding plate 168.

When the optical filter 152 is mounted on the holder main body 154 in this manner, the optical filter 152 is mounted on the holders 160, 162, and 164 when the holder main body 154 is mounted on the light source unit 100. Ball 1
The position is determined by 58 so as to be a predetermined angle (perpendicular) to the optical axis of the light beam.

The pressing plate 168 has the boss 188 in surface contact with the optical filter 152, so that the optical filter 152 is parallel to the plane including the contact point S of the three steel balls 158. The region including the position facing the contact point S of the steel ball 152 is uniformly pressed. Therefore, the optical filter 152 sandwiched between the steel ball 158 and the boss 188 of the holding plate 168 does not bend or curve.

Since the boss portion 188 of the pressing plate 168 is in surface contact with the optical filter 152, if the steel ball 158 faces this contact surface, the optical filter 152
It is pressed parallel to the steel ball 158. Therefore, it is not necessary to precisely align the steel ball 158 and the holding plate 168 that sandwich the optical filter 152. That is, the steel ball 158
If the contact point S of the optical filter 152 is within the area where the boss 188 of the holding plate 168 is in contact with the optical filter 152, the optical filter 152 is properly attached to the holder main body 154.

As described above, in the present embodiment, the holder main body 154 is maintained without impairing the planarity of the optical filter 152.
The optical filter 152 can be attached to the optical filter 152 very easily.

The above-described embodiment is an example of the present invention, and does not limit the configuration of the present invention.

For example, the holding plate 168 may be provided with a boss so as to make surface contact with at least a predetermined area including the contact point S of the steel ball 158.
If a predetermined plane is formed, an arbitrary shape can be applied.

In the present embodiment, the optical filter 1
Although the pressing plate 168 is brought into surface contact with the plate 52 and the pressing plate 168 is biased by a plurality of leaf springs (leaf springs 178 to 182), the biasing means is not limited to this. For example, as the urging means, leaf springs 178 to 182 are used.
May be integrated.

Further, in the present embodiment, the urging means and the holding plate are separately provided. However, the surface support member is brought into surface contact with a predetermined area of the optical filter 152 to at least contact the optical filter 152. The urging means may be suppressed and the plate may be integrated as long as the pressure is evenly pressed in the area where the pressure is applied.

In this embodiment, the optical filter (（wavelength plate) 152 has been described as an example of a flat optical member. However, if the optical member is a flat optical member, a light source unit such as a parallel flat plate or an aperture is used. The present invention can be applied to an optical member holder to which various optical members forming the 100 optical systems are attached.

In this embodiment, the printing plate 12 is wound around the rotary drum 54 to perform scanning exposure.
Although described using 0, the present invention is not limited to the printing plate 12, and other photosensitive lithographic printing plates, and optical members used for a scanning optical system for exposing various photosensitive materials such as photographic paper and film are attached. The present invention can be applied to an optical member holder.

[0102]

As described above, according to the present invention, a flat optical member is sandwiched between a point support member and a surface support member and attached to the holder main body. It has an excellent effect that it can be attached to the main body.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an image exposure apparatus applied to the present embodiment.

FIG. 2 is a schematic configuration diagram illustrating a recording unit of the image exposure apparatus.

FIG. 3 is a schematic configuration diagram illustrating a sub-scanning device provided in a recording unit.

FIG. 4 is a schematic perspective view of a light source unit provided in the sub-scanning device.

FIG. 5 is an exploded perspective view showing a schematic configuration of a holder to which the present invention is applied.

FIG. 6 is a schematic configuration diagram showing the arrangement of a steel ball attached to a holder main body and a boss of a holding plate.

FIG. 7 is a schematic configuration diagram showing the vicinity of a contact portion between a steel ball and a holding plate to an optical filter.

8A is a schematic cross-sectional view showing a main part of a holder having a conventional configuration in which a filter is sandwiched between steel balls, and FIG. 8B is a schematic diagram showing a change in the filter according to a relative position of the steel ball sandwiching the filter. FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Image exposure apparatus 12 Printing plate 22 Recording part 54 Rotating drum 56 Recording head part 100 Light source unit 126 Optical system assembly 150 Holder (optical member holder) 152 Optical filter (optical member) 154 Holder main body 158 Steel ball (point support member) 168 Holding plate (surface support member) 178, 180, 182 Leaf spring (biasing means) 188 Boss

Claims (3)

[Claims] 1. A holder for an optical member to which a flat optical member is attached, comprising: a holder main body for holding the optical member; and a predetermined position of the holder main body facing one surface of the optical member. Three point support members that are arranged and positioned by contacting each other to position the optical member, and a predetermined position of the optical member that is arranged to face the other surface of the optical member and faces each of the point support members. A surface support member that makes surface contact with the region and sandwiches the optical member between the point support member and the surface support member. 2. The optical member holder according to claim 1, wherein the point support member is a sphere provided at a predetermined position of the holder main body. 3. A pressing plate in which the surface supporting member faces at least each of the point supporting members; and urging means attached to the holder body for urging the pressing plate toward the point supporting members; The optical member holder according to claim 1, further comprising: