JPH11191827A - Image reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a sensor holding member from being deviated in unwanted direction during adjustment by providing the holding member with a hole for sensor position adjustment and a guide hole for regulating an adjusting direction, and adjusting the position of a sensor through the hole for position adjustment while regulating the adjusting direction through the guide hole. SOLUTION: A holding member 5a for a sensor 4 is formed in the shape of slender plate and a laterally long hole 5(A) for eccentricity adjustment, hole 5(B) for adjusting direction guide and hole 5(C) for fixture for fixing the holding member 5a on a frame 1 with a machine screw or the like are respectively provided at parts near both its terminals. The position of the sensor (sensor substrate) 4 is adjusted with respect to the frame 1 so as to exactly form an image out of an object on a line sensor through an adjusting tool and eccentric driver or the like while using the hole 5(A) for adjustment of the holding member 5a. In that case, a pin 8 provided on the frame is loosely fitted into the hole 5(B) for adjusting direction guide of the holding member 5a and the holding member 5a can be freely moved in longitudinal direction but the movement in lateral direction is regulated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image reading apparatus used in a copying machine, a facsimile, etc., and more particularly, a line sensor used in an optical print head, a self-scanning print head, etc., is positioned with respect to a frame constituting a housing. The present invention relates to an image reading apparatus which can be mounted in an adjustable manner, and further relates to a frame capable of accurately holding a roof prism lens array (RPLA) in order to bring out the optical performance of the RPLA.

[0002]

2. Description of the Related Art For adjusting the position of a sensor of a reduction optical system of an image reading apparatus, for example, in order to accurately form an image of an object on the sensor, an adjustment slot of a sensor holding plate, an eccentric knob, and a lens are used. Using the eccentric bush of the guide plate arranged between the block and the sensor holding plate,
There has been known one in which the movement can be adjusted in each of the axis, Y-axis, and rotation directions (see Japanese Patent Application Laid-Open No. 5-276309). In the same-size sensor, for example, as shown in FIG. 20, a sensor (sensor substrate) 33 is positioned and attached to an aluminum extrusion frame 32 for attaching the sensor by a jig (not shown). As shown in FIG. 21, a sensor (sensor board) 33 is directly attached to the main body frame to attach it to the frame 31.

However, in the conventional sensor adjusting means of the reduction optical system, since there is no guide for regulating the adjusting direction, the sensor may move in an unnecessary direction at the time of adjustment, and the eccentric knob and the eccentric bush may be displaced. Since screws are used, there is a problem in the adjustment accuracy and workability. Further, in the conventional sensor mounting method of the 1: 1 optical system, since the sensor is mounted on the main body frame by abutting, strict accuracy is required for each component, and as a result, component cost is high, and accuracy is guaranteed. The situation is tough.

[0004] As described in Japanese Patent Application Laid-Open No. 10-153751, an RPLA is a unit-size image-forming element, which is made of plastic by integral molding or the like and has a shape elongated in the array direction. Therefore, the image may be deformed by a very small amount of force, an image may be formed at a position deviated from a set image plane, and a focus position may be shifted depending on a holding method.

[0005]

SUMMARY OF THE INVENTION The present invention is to provide an image reading apparatus free from the above-mentioned conventional problems, and an object of the present invention is to provide an image reading apparatus in which a sensor holding member does not need to be moved during position adjustment. An object of the present invention is to provide an image reading apparatus which does not have a possibility of moving.

A second object of the present invention is to make it possible to easily attach a sensor (sensor substrate) to a sensor holding member without using an adhesive or the like, and to assemble the sensor to the sensor holding member. Is to be simplified.

Another object of the present invention is to eliminate the influence of warping due to the length of the holding member by omitting an unnecessary length of the sensor holding member.

It is an object of the present invention to improve the accuracy and workability of assembly by completely removing the float of the sensor holding member during the position adjustment of the sensor.

It is an object of the present invention to improve the workability by enabling the position of a sensor to be adjusted without using a jig.

An object of the present invention is to provide an assembling criterion for minimizing the influence of the accuracy of the roof prism lens array (RPLA) frame and the accuracy of the assembly on the RPLA, and to maintain the RPLA with high accuracy. And high-quality reading.

[0011] An object of the present invention is to make a positioning structure with an RPLA optical component a continuous formation structure so that a reference shape at the time of frame creation can be processed by one operation,
An object of the present invention is to improve the processing accuracy of the assembling reference as compared with the related art, and to further improve the positioning accuracy of the optical element.

An object of the invention described in claim 8 is that when the frame is formed by injection molding or the like, a mold structure that can be released vertically from the mold can be adopted, and a simpler mold structure is adopted. Thus, the accuracy of the mold can be improved, the assembling time can be further reduced, and assembling suitable for mass production at low cost can be realized.

The object of the present invention described in claim 9 is that, by using a rib structure as the reference position structure to be combined with the RPLA, it is possible to cope with the additional processing of only the rib portion, thereby shortening the delivery time of die making and This is to improve the accuracy.

The object of the invention described in claim 10 is that RPLA
Are pressed against the reference plane A and the reference plane B independently of each other to accurately maintain a desired position and obtain high-quality imaging performance.

An object of the present invention is to disperse the amount of force in the reference A and reference B directions by the amount of pressing force in one direction, and to reliably press the RPLA against the respective reference surfaces and to precisely place the RPLA at a desired position. The RPLA can be held accurately with a small number of holding members, and high-quality reading can be performed.

An object of the present invention is to provide a frame provided with an assembling reference adopting a V-shaped structure, which makes it possible to assemble the RPLA optical element very easily while maintaining the assembling accuracy. It is designed to achieve both improvement and reduction in assembly cost.

The object of the invention described in claim 13 is that RPLA
In the combination of the aperture array and the aperture array, the pressing member can accurately position the RPLA and the aperture array, and can prevent a deviation between the lens opening and the aperture.

The object of the invention described in claim 14 is that the roof prism lens array and the aperture array are not shifted and combined in the direction parallel to the ridge line of each prism of the roof prism lens array, but the ridge line of each prism. Are held on a frame or the like by means for regulating the direction of deviation of the normal direction of the plane including.

[0019]

According to a first aspect of the present invention, there is provided an image reading apparatus in which an equal-magnification image of an original is formed on a line sensor. An image reading apparatus is provided in which a guide hole for regulating is provided, and the position of the sensor can be adjusted with respect to a frame by the position adjusting hole while regulating the adjustment direction by the guide hole.

According to a second aspect of the present invention, there is provided the image reading apparatus according to the first aspect, wherein the sensor holding member is made of a spring material having claws for holding the sensor.

According to a third aspect of the present invention, in the image reading apparatus of the first or second aspect, the sensor holding member is a pair of left and right members.

According to a fourth aspect of the present invention, there is provided an image reading apparatus according to any one of the first to third aspects, further comprising a pressing member for pressing the sensor and the sensor holding member against the frame. is there.

According to a fifth aspect of the present invention, there is provided the image reading apparatus according to any one of the first to fourth aspects, further comprising an eccentric pin rotatably press-fitted into the frame and engaged with the position adjusting hole. It is a reader.

According to a sixth aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame reader is an image reading apparatus having a reference which is combined so as to be positioned in a direction perpendicular to a plane including a ridge line of each prism of the roof prism lens array in the same direction as each ridge line direction.

According to a seventh aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame is a frame in which the reference is provided in two directions, a direction perpendicular to the plane including the ridge line of each prism of the roof prism lens array and the same direction as each ridge line direction, and the structure of the reference surface of the frame is a prism. This is an image reading device formed in a groove shape in the arrangement longitudinal direction.

According to an eighth aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame is a frame in which the reference is provided in two directions, that is, a direction perpendicular to a plane including the ridge line of each prism of the roof prism lens array and the same direction as each ridge line direction. An image reading apparatus having a structure that does not interfere even when the roof prism lens array moves in a vertically upward direction with a positioning pin of the prism lens array.

According to a ninth aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame is a frame provided with references in two directions, a direction perpendicular to a plane including the ridge line of each prism of the roof prism lens array and the same direction as each ridge line direction, and the reference surface of the frame is formed in a rib shape. This is an image reading device having a formed structure.

According to a tenth aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame has a reference in a direction perpendicular to the plane including the ridge line of each prism of the roof prism lens array and in the same direction as each ridge line direction, and the roof prism lens array is pressed by the pressing members in the two directions. This is an image reading device that holds the reference.

According to an eleventh aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame has a reference in a direction perpendicular to a plane including the ridge line of each prism of the roof prism lens array and in the same direction as each ridge line direction, and is located at one position from the center of the aperture array disposed in front of the roof prism lens array. An image reading apparatus holds a roof prism lens array on the basis of a reference by a pressing member biasing in a direction.

According to a twelfth aspect of the present invention, there is provided an image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The frame comprises a frame having a reference plane that is a direction perpendicular to a plane including the ridge line of each prism of the roof prism lens array and a plane normal to the optical axis of one lens array of the roof prism lens, The image reading apparatus is configured to hold the roof prism lens array by applying a pressing spring member that biases in one direction.

According to a thirteenth aspect of the present invention, there is provided an image reading apparatus in which an equal-magnification image of a document is formed on a line sensor, a roof prism lens array, a frame for holding the roof prism lens array, and an aperture array. The roof prism lens array, the frame and the aperture array are assembled in the same direction, and are attached in the direction perpendicular to the plane including the ridge line of each prism of the roof prism lens array and in the same direction as each ridge line direction. This is an image reading device that is a reference for combining so as to perform contact positioning.

According to a fourteenth aspect of the present invention, there is provided an image reading apparatus in which an equal-magnification image of a document is formed on a line sensor, a roof prism lens array, a frame for holding the roof prism lens array, and an aperture array. An image reading apparatus comprising: a roof prism lens array and an aperture array; and a reference for assembling the roof prism lens array with respect to a plane having a normal to an optical axis of two sets of lens arrays orthogonal to each other.

[0033]

FIG. 1 shows a cross section of an RPLA sensor unit which is a unit-size imaging device according to the present invention.
In the figure, reference numeral 1 denotes a frame of the unit, 2 denotes an RPLA (1: 1 imaging element), 3 denotes a light source for illumination, and 4 denotes a sensor (line sensor). The light is bent by 90 ° and focused and formed on the sensor 4.

FIG. 2 shows an embodiment of the first aspect of the present invention. Reference numeral 4 denotes a sensor (sensor substrate), and reference numeral 5a denotes a holding member for the sensor 4. The holding member 5a has an elongated plate shape so that the line sensor can be held on one surface thereof, and a horizontally long eccentricity adjusting hole 5 (a) (this hole is a hole shown in FIG. Not limited to this, a notch may be used, and a hole is also used here. An adjustment direction guide hole 5 (b), a fixing hole 5 for fixing the holding member 5a to the frame 1 with a screw or the like is used. C) are provided.

The sensor (sensor substrate) 4 is provided with the holding member 5
The position of the object 1 is adjusted with respect to the frame 1 by using an adjustment tool (not shown), an eccentric driver, or the like using the adjustment hole 5 (a) of FIG. . At this time, since the pin 8 provided on the frame is loosely fitted into the adjustment direction guide hole 5 (b) of the holding member 5a, the holding member 5a can be freely moved within a certain range in the vertical direction in FIG. Although the movable member can move, the lateral movement is restricted, and therefore, the holding member 5 can be moved as in the above-described conventional device.
There is no possibility that a is shifted in an unnecessary direction during adjustment. When the necessary adjustment is completed with an adjusting tool or the like, the holding member is fixed at that position using a fixing hole 5 (c) with a screw or the like.
Fixed to

FIG. 3 shows an embodiment of the second aspect of the present invention. Reference numeral 4 denotes a sensor (sensor substrate), and reference numeral 5b denotes a sensor holding plate. The sensor holding member 5b has the same shape as in the above-described embodiment, and has eccentricity adjustment holes 5 (a) near both ends thereof and the adjustment direction similar to the sensor holding member described with reference to FIG. Guide hole 5
(B), a fixing hole 5 (c) for fixing the holding member 5b to the frame 1 is provided.

In this embodiment, the sensor holding member 5b is further provided with claws 5 (d) for holding the sensor 4 at upper and lower ends in the longitudinal direction of the sensor holding member 5b. A projection 5 (e) for regulating the longitudinal movement of the sensor is provided adjacent to d). The sensor holding member 5b is made of a spring material, so that the sensor can be fixed to the upper and lower claws with a single touch by using the elasticity of the claws 5 (d). With this configuration, since the sensor 4 and the sensor holding member 5b do not need to be bonded to each other, the process of assembling the sensor 4 to the sensor holding member 5b can be simplified.

FIG. 4 shows an embodiment of the third aspect of the present invention. In the figure, 4 is a sensor (sensor substrate), 5c
Reference numerals 1 and 5c2 denote holding members, respectively. The structure of the holding members 5c1 and 5c2 is the same as that of the embodiment of the second embodiment described in relation to FIG. 3, but the shape where the left and right portions are left out and the intermediate portion is omitted, that is, the shape which is separated right and left Has made. With such a configuration of the holding member, an unnecessary length can be omitted, and the influence of the warping of the holding member can be eliminated.

FIG. 5 shows an embodiment of the present invention. In the figure, 4 is a sensor (sensor substrate), 5 is a sensor holding member, and 6 is a pressing member. The holding member 6 has a first central portion 6 (c) on a flat plate, which is narrower at one end at a central portion than the one end portion and extends from the front side of the main body piece toward the back side as viewed from the mounting side. A leg 6 (a) is provided, and a notch 6 (d) for penetrating an eccentric pin to be described later is formed at the center of an end of the center piece 6 (c) opposite to the first leg. Are formed, and both ends of the notch are narrower than the first leg pieces and extend in the direction toward the rear surface side like the first leg pieces 6 (a). Are provided, respectively.

Since the holding member 6 has the above configuration,
The sensor 4 and the sensor holding member (5
a, 5b, 5c1, 5c2), the holding member 6 is attached to the sensor (sensor substrate) 4 and the sensor holding members (5a, 5b, 5c1, 5c1) by the elasticity of the first and second leg pieces. 5c2) is pressed against the frame 1. At this time, the hole 5 (e) of the sensor holding member 5 corresponding to the screw hole 6 (e) of the holding member is made larger in diameter than the screw hole 6 (e). When the sensor 4 and the sensor holding member 5 are pressed by the holding member, the sensor holding member can be moved for position adjustment. Therefore, it is possible to completely prevent the sensor 4 from floating during the adjustment.

FIG. 6 shows an embodiment of the fifth aspect of the present invention. The configuration other than the eccentric pin 7 is the same as that shown in FIG. The eccentric pin 7 is press-fitted into the frame 1 so as to be rotatable. The eccentric pin 7 is inserted into the eccentricity adjusting hole 5 (a) of the sensor holding member and rotated, whereby the sensor with respect to the frame 1 is rotated. The position can be easily adjusted. With this configuration, a jig (tool) such as an eccentricity adjusting jig or an eccentric driver is not required. Even if a jig is used, the sensor position is kept at the correct position by the eccentric pin even after the jig (tool) is removed, so that the adjustment can improve the workability in the stable adjustment work.

FIG. 7 is a sectional view of an essential part showing an embodiment of the invention according to claim 6, and FIG. 8 is a perspective view of the frame shown in FIG. 7, in which 10 is a frame, and 11 is an RPLA (roof). Prism lens array), 12 is an aperture array, 1
3 is an equal magnification sensor, 14 is a light source, 15 is a light source cover, 16
Is a cover member, 17 is a cover glass, 18 is a sensor holding member, and 19 is an aperture array holding member.

The reference A and the reference B shown in FIGS. 7 and 8 are set in the frame 10 of the present invention.
A reference plane and a boss are also set in the PLA. The direction in which the parts are brought together is a reference A which is a reference to be applied in a direction perpendicular to a plane including the ridge direction of each prism of the RPLA 11.
And a reference B serving as a reference in a direction parallel to the ridgeline direction of each prism of the RPLA.

By employing the frame structure provided with the reference positions as described above, the image formation position of the RPLA can be accurately positioned. As a specific holding method, a holding member that presses the reference of the RPLA 11 as a reference for positioning the frame 10 in two directions may be used, or may be fixed and held by adhesion or fusion. The advantage of adopting such a positioning method will be described below.

In the RPLA, as is well known, information on a document surface or the like is converted into substantially parallel light by each lens of the first lens array, and the light path is set to 90 degrees by internal reflection of the roof prism.
And is converged by each lens of the second lens array to form an image at a desired position. Since the light-collecting functions of the first lens and the second lens are the same, the object point and the imaging point are conjugate positions located at the same distance from the first lens array and the second lens, respectively. . The lens is held so that the lens is set at a position where the resolving power reaches a peak in accordance with the focusing power of the lens. However, RPLA
However, the imaging performance may be deteriorated due to the accuracy of holding the optical element in the actual unit.

In the present invention, the frame 10 and the RPLA 1
1 even if there is an intervening object, or if the reference is not matched or the shape is shifted due to a shape error due to the warpage or bending of the integrally formed imaging element. The following advantages are obtained by designing the assembly so that the distances are combined in a direction in which the distances are the same or apart from each other.

That is, the direction to hit the reference A direction is
Even if the position shifts in this direction, the distance between the object point and the lens and the distance between the lens and the image forming point change while having the same value. Although the performance of the RPLA is degraded when the performance of a single lens deviates from a certain focal length, the RPLA maintains a one-to-one equal magnification relationship that maintains a conjugate position, that is, maintains a conjugate positional relationship. At the position, it is possible to prevent deterioration of the imaging performance of the synthetic lens system as much as possible.

FIG. 9A is a diagram showing the relationship between the image forming light of the sensor position set value and the MTF characteristic, and FIG. 9B is a diagram showing the image forming light when the sensor approaches the lens by ΔDs from the set position. M
FIG. 4 is a diagram showing a relationship between TF characteristics, and shows an expanded RPLA optical system for explanation. As shown in the figure, the performance of a single lens shifts the focal position to a position farther away from the image forming surface as the document surface approaches, as in the characteristics of the optical axis shown in the figure. The peak of the imaging performance comes to the position where it was kept.

FIG. 10 shows that when the RPLA is set to the frame of the present invention, the distance between the document surface (object surface) and the RPLA lens and the RPLA
The amount of deviation between LA and the imaging plane interval is both ΔDs, indicating that the conjugate relationship is maintained. The actual positional deviation amount is a small value of several tens to several hundreds of microns, and FIG. 10 is exaggerated for explanation.

In FIG. 7, the RPLA 11 is held by being pressed through the aperture array 12 in two directions, the reference A direction and the reference B direction. RPL in frame 10
A hole 10a corresponding to the boss of A11 is formed. Similarly, the aperture array 12 and the RPLA 11 are positioned at the positions of the reference A ′ and the reference B ′ shown in the same direction as the reference A direction and the reference B direction, and are held by the holding member 19. A light source 14 is disposed on a side surface of the frame 10, and a line sensor 13 is disposed at an image forming position.
It constitutes an image reading device. The sensor 13 is held by a sensor pressing member 18 from the back. In the illustrated embodiment, a boss is set in the RPLA 11 and a hole corresponding to the shape is formed in the frame 10. However, the boss may be formed in the frame 10 and a hole may be formed in the RPLA 11.

FIG. 11 is a view showing a frame structure according to the present invention.
The positioning shape with A is such that a groove 10b is formed along the longitudinal direction of the prism array.

FIG. 12 is a view showing a frame according to the present invention.
And the reference plane B are set, and the reference plane A has a normal in the same direction as the direction perpendicular to the plane including the ridge line of each prism of the RPLA.
And a reference plane B serving as a reference applied in the same direction as the direction parallel to the direction of the ridgeline of each prism of the RPLA.
A positioning reference 10 such that the reference shape combined with A can drop RPLA vertically downward.
c. Even if the RPLA 11 shown in the cross-sectional view of FIG. 7 is moved vertically upward, the RPLA 11 does not hit the reference boss.

FIG. 13 is a perspective view of the frame according to the ninth aspect of the present invention.
Is set, and the reference plane A has an abutment reference in the same direction as the direction perpendicular to the plane including the ridge line of each prism of the RPLA.
And a reference plane B serving as an application reference in the same direction as the direction parallel to the ridge line of each prism of the RPLA. The structure of the reference plane having the reference planes A and B is
d.

FIG. 14 is a sectional view of an essential part for explaining an embodiment of the tenth aspect of the present invention. In FIG. 14, parts having the same functions as those of the embodiment shown in FIG. The same reference numbers are assigned. In this embodiment, the RPLA 11
Of the reference A and the reference B in the vertical direction via the aperture array 12 in front of the
19b, for example, it is pressed and held by a leaf spring or the like. The pressing direction as a specific embodiment is set independently in two directions as shown in the drawing. As a specific structure,
It may be constituted by a spring member using a sheet metal member, or may be a holding spring part made of plastic.

FIG. 15 is a sectional view of an essential part for explaining an embodiment of the invention according to the eleventh aspect. FIG. 15 is a view showing another embodiment of a specific method of pressing the pressing member. , An aperture array 1 disposed in front of the RPLA 11
The center portion of the second member 2 is pressed and held by a pressing member 19, for example, a leaf spring or the like, so that the pressing force is distributed in the perpendicular direction of the reference plane A and the perpendicular direction of the reference plane B, which are orthogonal to each other. The pressing direction as a specific embodiment is shown in FIG.
As shown in FIG. 5, it is held down in only one direction toward the downward direction.

FIG. 16 is a perspective view of a frame according to the twelfth aspect of the present invention, and FIG. 17 is a sectional view of an image reading apparatus using the frame shown in FIG. 1. A frame 1 having a reference plane as a plane having a direction perpendicular to a plane including the same and a normal line in the same direction as the optical axis of one lens array of the roof prism lens 11.
0. This reference plane has a V-shaped structure that crosses each other at 45 degrees as shown in the figure. Also, RP
An imaging element composed of the LA 11 and the aperture array 12 is applied to the reference A and the reference C inside the V-shaped structure,
It is held by a pressing spring member 19 that urges in one direction.

The structure of the thirteenth invention will be described with reference to FIG. 7 described in the first invention. A thirteenth aspect of the present invention provides an aperture array and a RP disposed in front of the RPLA.
Regarding the positioning of the LA, the reference A ′ and the reference B ′ shown in the figure are set in the same direction as the reference A and the reference B of the frame. The direction of each reference is RPLA
A reference A 'having a surface having a normal in a direction perpendicular to a plane including the ridge line of each prism, and a reference B' for determining a position in a direction parallel to the direction of the ridge line of each prism of the RPLA. I have.

FIG. 18 is a schematic diagram showing the construction of the fourteenth embodiment of the present invention, wherein two sets of lens arrays of the roof prism lens array 11 which are orthogonal to each other are used as a reference for assembling the roof prism lens array 11 and the aperture array 12. A reference A based on a plane parallel to the optical axis 1 and a reference A 'orthogonal to the reference A' and a reference B based on a plane parallel to the optical axis 2 and a reference A The combination of the RPLA and the aperture array is based on the criterion B '. FIG.
FIG. 9 shows another embodiment of the invention according to claim 14, in which the reference A and the reference A 'shown in FIG. 18 are parallel to the plane including the ridge line of each prism of the roof prism lens array 11. The reference B and the reference B 'perpendicular thereto are the same as those of the embodiment shown in FIG.

[0059]

According to the first aspect of the present invention, a hole for adjusting the position of the sensor and a guide hole for regulating the adjustment direction are provided in the sensor holding member, and the hole for adjusting the position is regulated by the guide hole. Thus, the position of the sensor can be adjusted, so that there is no possibility that the holding member 5a is shifted in an unnecessary direction during the adjustment.

According to the second aspect of the present invention, since the sensor holding member is made of a spring material having a claw for holding the sensor, the sensor can be moved up and down by utilizing the resilience of the claw 5 (d). Since the sensor can be fixed to the claw with one touch, and the sensor and the sensor holding member need not be bonded, the process of assembling the sensor to the sensor holding member can be simplified.

According to the third aspect, since the sensor holding member is a pair of left and right members, an unnecessary length can be omitted, and the influence of the warping of the holding member can be eliminated.

According to a fourth aspect of the present invention, since the sensor and the sensor holding member are provided with a pressing member for pressing the sensor and the sensor holding member against a frame constituting the housing, the sensor and the sensor holding member are pressed by the holding member. The sensor holding member can be moved for position adjustment, and the floating of the sensor during adjustment can be completely prevented. In addition, workability at the time of assembly can be improved thereby.

According to the fifth aspect of the present invention, since the eccentric pin is rotatably press-fitted into the frame and is engaged with the position adjusting hole, the eccentric adjusting jig or the eccentric driver can be fixed. Tools (tools) become unnecessary, and work efficiency is improved. Even if a jig is used, the sensor position is kept at the correct position by the eccentric pin even after the jig (tool) is removed, so that the adjustment is stable and the workability in the adjustment work can be improved.

Effect corresponding to claim 6: There is an assembling criterion for minimizing the influence of the frame accuracy and the assembling accuracy on the RPLA, the RPLA can be held with high accuracy, and high-quality reading can be performed.

According to the seventh aspect of the invention, the positioning structure for the RPLA optical component is formed continuously. For this reason, the reference shape at the time of frame creation can be processed by one operation, and the processing accuracy of the assembling reference can be improved more than before, and the positioning accuracy of the optical element can be further improved.

According to the eighth aspect of the invention, when the frame is made by injection molding or the like, the mold structure is simplified, and the frame can be made more accurately. This is because usually, as the mold for injection molding has a simple structure capable of releasing the molded product, the slide structure does not have to be adopted. By employing the shape of the present invention, it is possible to adopt a mold structure in which the mold is released vertically upward from the mold. A simpler mold structure can be adopted, the accuracy of the mold can be improved, and the frame accuracy can be improved. In addition, the RPLA optical element can be assembled such that the RPLA optical element is dropped from above, so that the assembling time can be further shortened, and an assembling method suitable for mass production at low cost can be realized.

Effect corresponding to claim 9: Since the structure at the reference position to be combined with RPLA employs a rib-like structure, the following advantages are obtained. As a method of forming the frame, the frame is integrally formed by injection molding which is a conventional technique. However, there is a method of making the mold accuracy to the limit and the transferability is improved to the limit.However, it is usual to correct the mold in reverse considering the amount of warpage and bending due to molding. Is being done. By adopting the structure of the present invention, it is possible to accurately create the shape of the frame as the final molded product by correcting the number of ribs on the surface shape that is the reference of the frame mold. Becomes In other words, by making the reference portion a rib structure, it is possible to cope with additional processing of only this rib portion,
Shorter delivery time and improved accuracy of mold making are achieved.

The effect corresponding to claim 10: the reference A direction,
Since the parts to be pressed independently in the reference B direction are set,
The RPLA is pressed against the reference plane A and the reference plane B against the frame, and is accurately held at a desired position. Thereby, the performance of the RPLA can be brought out, and high-quality imaging performance can be obtained.

According to the eleventh aspect, the pressing force in one direction disperses the force in the reference A and reference B directions.
These are reliably pressed against the respective reference surfaces and are accurately held at desired positions. By adopting the frame structure of the present invention, the RPLA can be held accurately with a small number of pressing members, and high-quality reading can be performed.

The effect corresponding to claim 12 is that the frame structure is very simple, and the incorporation of the RPLA and the aperture array into the frame is very simple. Specifically, only the work of dropping into the frame at the time of assembly,
Temporarily accurate positioning becomes possible. Such a V
Since this is an assembly reference employing a character structure, the positional accuracy can be maintained by holding the aperture array with a simple pressing member in one direction from above. The effect of the present invention is that the frame provided with the assembling reference adopting the V-shaped structure makes it possible to very easily assemble while maintaining the assembling accuracy of the RPLA optical element, thereby improving the accuracy and reducing the assembling cost. Can be compatible.

According to the thirteenth aspect, in the combination of the RPLA and the aperture array, the RPLA and the aperture array can be accurately positioned by the pressing member urged in the pressing direction shown in FIG. The displacement of the aperture can be prevented. It is possible to provide a positioning method that maintains high-quality imaging performance without deteriorating optical performance due to aperture shift.

According to the fourteenth aspect, it is possible that the roof prism lens array and the aperture array are shifted in the direction parallel to the ridge line of each prism of the roof prism lens array and combined by the structures of the reference 1 and the reference 2. Instead, the prism may be held on a frame or the like by means for regulating the direction of deviation of the plane including the ridge line in the normal direction. By employing the assembling method and the frame structure according to claims 6 to 13, a highly accurate assembling method can be presented without further reducing the performance of RPLA.

[Brief description of the drawings]

FIG. 1 is a sectional view of an RPLA sensor unit according to an embodiment of the present invention.

FIG. 2 is a diagram showing a sensor holding unit used in the RPLA sensor unit.

FIG. 3 is a view showing another sensor holding means used in the RPLA sensor unit.

FIG. 4 is a view showing still another sensor holding means used in the RPLA sensor unit.

FIG. 5 is a diagram showing an embodiment of a holding member used in the RPLA sensor unit.

FIG. 6 is a diagram for explaining position adjustment of a sensor holding unit using an eccentric pin used in the RPLA sensor unit.

FIG. 7 is a sectional view of a main part according to the embodiment of the present invention.

8 is a perspective view of the frame shown in FIG.

FIG. 9 is a diagram illustrating a relationship between imaging light and MTF characteristics.

FIG. 10 is a diagram showing that a conjugate relationship is maintained when RPLA is set in the frame of the present invention.

FIG. 11 is a view showing a frame structure according to the present invention described in claim 7;

FIG. 12 is a view showing a frame according to the present invention described in claim 8;

FIG. 13 is a perspective view of the frame according to the ninth aspect of the present invention.

FIG. 14 is a sectional view of an essential part for explaining an embodiment of the invention of claim 10;

FIG. 15 is a sectional view of an essential part for describing an embodiment of the invention of claim 11;

FIG. 16 is a perspective view of the frame according to the twelfth aspect.

17 is a sectional view of an image reading apparatus using the frame shown in FIG.

FIG. 18 is a main part configuration diagram showing a configuration of the invention of claim 14;

FIG. 19 is a view showing another embodiment of the invention of claim 14;

FIG. 20 is a diagram illustrating a conventional unit-magnification optical system sensor adjustment unit.

FIG. 21 is a diagram for explaining another conventional unit-size optical system sensor adjusting unit.

[Explanation of symbols]

1. Frame of RPLA sensor unit 2. RPLA
(Imaging element), 3 ... Light source for illumination, 4 ... Sensor (line sensor), 5a, 5b ... Sensor holding member, 10 ... Frame, 11 ... RPLA, 12 ... Aperture array, 13
... 1: 1 sensor, 14 ... light source, 15 ... light source cover, 16 ...
Cover member, 17: cover glass, 18: sensor pressing member, 19, 19a, 19b: aperture array pressing member.

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Goichi Akanuma 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (14)

[Claims] In an image reading apparatus for forming an equal-magnification image of a document on a line sensor, a sensor holding member is provided with a hole for adjusting a sensor position and a guide hole for regulating an adjustment direction. An image reading apparatus, wherein the position of the sensor can be adjusted with respect to a frame by the position adjusting hole while regulating an adjusting direction. 2. The image reading apparatus according to claim 1, wherein the sensor holding member is made of a spring material having a claw for holding the sensor. 3. An image reading apparatus according to claim 1, wherein said sensor holding member comprises a pair of left and right members. 4. The image reading apparatus according to claim 1, further comprising: a pressing member that presses the sensor and the sensor holding member against the frame. 5. The image reading apparatus according to claim 1, further comprising an eccentric pin rotatably press-fitted into said frame and engaging with said position adjusting hole. Image reader. 6. An image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. An image reading apparatus comprising: a reference which is combined with a direction perpendicular to a plane including a ridge line of each prism of a roof prism lens array in the same direction as each ridge line direction to perform positioning. 7. An image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array, wherein the frame has a roof structure. A frame provided with a reference in two directions, a direction perpendicular to a plane including a ridge line of each prism of the prism lens array and the same direction as each ridge line direction, wherein a structure of a reference surface of the frame is a groove in a prism array longitudinal direction. An image reading apparatus characterized by being formed in a shape. 8. An image reading apparatus for forming an equal-magnification image of a document on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array, wherein the frame is a roof prism lens array. A frame provided with references in two directions, a direction perpendicular to the plane including the ridge line of each prism of the prism lens array and the same direction as each ridge line direction. The structure of the reference surface of the frame is determined by positioning the roof prism lens array. An image reading device having a structure in which even when the roof prism lens array moves in a vertically upward direction, a pin for use does not interfere. 9. An image reading apparatus for forming an equal-magnification image of an original on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. A frame provided with a reference in two directions, a direction perpendicular to the plane including the ridge line of each prism of the prism lens array and the same direction as each ridge line direction, and the reference surface of the frame is formed in a rib shape. An image reading apparatus, comprising: 10. An image reading apparatus for forming an equal-magnification image of a document on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The prism lens array has a reference in a direction perpendicular to the plane including the ridge line of each prism and in the same direction as each ridge line direction, and the roof prism lens array is held on the reference by a holding member biasing in the two directions. An image reading apparatus, comprising: 11. An image reading apparatus for forming an equal-magnification image of a document on a line sensor, comprising a roof prism lens array and a frame for holding the roof prism lens array. The roof prism lens array has a reference in a direction perpendicular to the plane including the ridge line of each prism and in the same direction as each ridge line direction, and biases in one direction from a central portion of the aperture array arranged in front of the roof prism lens array. An image reading apparatus, wherein a roof prism lens array is held based on the reference by a pressing member. 12. An image reading apparatus in which an equal-magnification image of a document is formed on a line sensor, the image reading apparatus includes a roof prism lens array and a frame for holding the roof prism lens array, wherein the frame is The roof prism lens array is composed of a frame having a reference plane that is perpendicular to the plane including the ridge line of each prism and the plane whose normal line is the optical axis of one lens array of the roof prism lens, and is biased in one direction. An image reading apparatus, wherein the roof prism lens array is held by applying a pressing spring member. 13. An image reading apparatus configured to form an equal-magnification image of a document on a line sensor, comprising: a roof prism lens array; a frame for holding the roof prism lens array; and an aperture array. The assembling reference of the roof prism lens array, the frame and the aperture array are in the same direction, and the roof prism lens array is positioned so as to be applied in the direction perpendicular to the plane including the ridge line of each prism and in the same direction as the ridge line direction. An image reading device, which is a reference to be combined. 14. An image reading apparatus configured to form an equal-magnification image of a document on a line sensor, comprising: a roof prism lens array; a frame for holding the roof prism lens array; and an aperture array. An image reading apparatus, wherein a reference for assembling a roof prism lens array and an aperture array is based on a plane whose normal line is the optical axis of two sets of lens arrays orthogonal to each other of the roof prism lens array.