JPH11284807A - Image reading device - Google Patents

Abstract

(57) [Problem] To provide an image reading device capable of attaching a mirror to a carriage with a simple structure. A carriage main body (31) has a positioning part (34) for positioning a mirror (62).
A spring member 35 is formed at a position facing the fourth member 4. The positioning part 34 and the spring member 3 are larger than the thickness a of the mirror 62.
The space b between the first and second electrodes 5 is formed small. Positioning unit 34
By press-fitting the mirror 62 between the spring member 35 and the spring member 35, the mirror 62 can be held and fixed by the elastic force of the spring member 35. Further, an adhesive is poured between the mirror 62, the positioning portion 34, and the spring member 35, so that the mirror 62 is more securely fixed.

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 for converting an image on a document into an electric signal.

[0002]

2. Description of the Related Art Conventionally, as a flatbed type image reading apparatus, a platen made of a transparent plate such as glass is provided on the upper surface of a box-shaped case, and a drive unit drives the platen inside the case. 2. Description of the Related Art There is known an apparatus provided with a carriage that moves in parallel. This carriage is configured by mounting a light source, a condenser lens, a line sensor in which a large number of photoelectric conversion elements are linearly arranged, and the like on a carriage body formed of aluminum die casting or the like. Irradiation light from the light source is reflected on the surface of the document on the document table, and is condensed on a line sensor by a condenser lens.

When reading an image, light from a light source is radiated on a document placed on a document table, reflected light from the document is condensed on a line sensor by a condensing lens, and the carriage is moved in the direction of arrangement of the line sensor elements. Is detected while being moved vertically and in parallel with the document surface, and the density of the document is converted into an electric signal.

In such an image reading apparatus,
In order to read a wide range of documents at high resolution with a small line sensor, and to reduce the size of the entire device, light from the document is reflected by a plurality of mirrors provided on the carriage and guided to a condenser lens, Generally, the optical path length is increased. Conventionally, as shown in FIG. 5, the mirror 120 is fixed to the carriage main body 110 by being clamped by a clamp member 130 separate from the carriage main body 110.

[0005]

However, in the above-described conventional image reading apparatus, the clamp member 130 for fixing the mirror 120 is required separately, so that the number of parts increases and the manufacturing cost increases. There was a problem of increasing.

An object of the present invention is to provide an image reading apparatus which can fix a mirror to a carriage with a simple structure.

[0007]

According to the image reading apparatus of the present invention, the carriage body has a positioning portion for positioning the mirror, and a spring member for sandwiching the mirror between the positioning portion and the spring member. However, since it is formed integrally with the carriage body, the mirror can be fixed to the carriage body with a simple structure without increasing the number of parts.

According to the image reading apparatus of the second aspect of the present invention, since the carriage main body is made of plastic, the weight of the carriage can be reduced. Further, it is easy to form a spring member having elasticity.

According to the image reading apparatus of the third aspect of the present invention, the mirror is fixed to the carriage body by the adhesive, so that the mirror can be fixed more securely.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 2 shows a schematic structure of a flat bed type image reading apparatus according to an embodiment of the present invention.

A document table 1 made of a transparent plate such as glass is provided on the upper surface of the box-shaped casing 2. A document 8 is attached to the surface of the document table 1 by a driving device (not shown) inside the housing 2.
A carriage 3 is provided that can reciprocate in parallel with the document surface on which the light source is placed, and a light source 4 and a line sensor 5 are mounted on the carriage 3. The irradiation light of the light source 4 is reflected on the surface of the original 8 and is reflected by mirrors 61, 62, 63,
Then, the light is condensed on the line sensor 5 by the condensing lens 7. The line sensor 5 has a CC
A charge accumulation type optical sensor in which a plurality of pixels such as D are linearly arranged perpendicular to the moving direction of the carriage is used. In the present embodiment, as shown in FIG.
1, mirror 62, mirror 63, mirror 62, mirror 64
The light is reflected twice by the mirrors 62 so that the light is reflected five times by the four mirrors to increase the optical path length from the document 8 to the condenser lens 7. At the end of the document table 1 in the direction of movement of the carriage 3, a white reference 9 having a highly reflective uniform reflection surface is provided.

The carriage 3 comprises a light source 4, a line sensor 5, mirrors 61, 62, 63, 64, a carriage body 31 as shown in FIG.
A component such as the condenser lens 7 is fixed. A positioning portion 34 for positioning the mirror 62 is formed on the carriage main body 31, and a spring member 35 is formed at a position facing the positioning portion 34. The positioning part 34 and the spring member 35 constitute a mirror mounting part. FIG.
As shown in the figure, the distance b between the positioning part 34 and the spring member 35 is formed smaller than the thickness a of the mirror 62. Mirror 62 between positioning portion 34 and spring member 35
, The mirror 62 can be held and fixed by the elastic force of the spring member 35. Further, it is desirable that an adhesive is poured between the mirror 62, the positioning portion 34, and the spring member 35 to more securely fix the adhesive.

Similarly, mirror 61 is sandwiched between positioning portion 32 and spring member 33, mirror 63 is sandwiched between positioning portion 36 and spring member 37, and mirror 64 is positioned between positioning portion 38 and spring member 39. Is sandwiched between.

In the line sensor 5, an amount of electric charge corresponding to the amount of light collected by each element is accumulated, and the accumulated electric charge is processed by a signal processing device 10 as shown in FIG. A
The / D converter 12 converts the data input from the line sensor 5 via the amplifier 11 into a digital signal and passes the digital signal to the shading corrector 13. The shading correction unit 13 corrects a variation in sensitivity of each element of the line sensor 5 and a variation in light amount of the light source 4 using data obtained by reading the white reference 9 before starting reading. The gamma correction unit 16 performs gamma correction using a predetermined gamma function, and converts the light amount signal output from the shading correction unit 13 into an image signal. The other correction unit 17 performs various conversions such as color correction, edge enhancement, and area enlargement / reduction.

The control device 14 includes a CPU, a RAM, and an RO.
M, etc., which controls the entire image reading apparatus and has an interface 1
5 is connected to an external image processing apparatus, for example, a personal computer.

Next, the operation of the image reading apparatus configured as described above will be described.

A user connects a personal computer (not shown) to the interface 15 of the image reading apparatus, places the document 8 on the document table 1, and designates a reading range and a reading resolution of the document from the personal computer to execute reading. Command.

When the execution of reading is instructed, the controller 14 turns on the light source 4 and moves the carriage 3 sequentially to each reading line position. As a result, an electric charge (signal electric charge) in an amount proportional to the reflectance of the original 8 is accumulated in the line sensor 5 at each reading line position. The electric charge accumulated in the line sensor 5 is supplied to the amplifier 11 after a lapse of a predetermined time.
And the line sensor 5 is moved to the next reading line position.

An output signal from the amplifier 11 is converted into digital light quantity signal data by an A / D converter 12,
Various corrections are performed in the shading correction unit 13, the gamma correction unit 16, and the other correction unit 17, and the correction is output to a personal computer or the like via the interface 15.

By moving the carriage 3 and repeating the above processing for each reading line, an image in a specified range is output to a personal computer or the like.

In this embodiment, a flatbed type image reading apparatus for reading reflected light from a document has been described. However, the image reading apparatus is provided with a light source above a document table and reads transmitted light of a transparent document. Can obtain exactly the same effect.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating a mirror mounting portion of a carriage in an image reading apparatus according to an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a schematic structure of an example of a flatbed type image reading apparatus according to the present invention.

FIG. 3 is a perspective view illustrating a carriage main body of the image reading apparatus according to the embodiment of the present invention.

FIG. 4 is a block diagram illustrating a functional configuration of a signal processing device of the image reading device according to the present invention.

FIG. 5 is a schematic view showing a mirror mounting portion of a carriage in a conventional image reading apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Document stand 2 Case 3 Carriage 31 Carriage main body 32, 34, 36, 38 Positioning part 33, 35, 37, 39 Spring member 4 Light source 5 Line sensor 61, 62, 63, 64 Mirror 7 Condensing lens 8 Document 9 White Standard 10 Signal processing device

Claims (3)

[Claims] 1. A carriage body, a light source for irradiating a document, a mirror for reflecting light from the document, a lens for condensing light reflected by the mirror, and an electric signal for condensing the light condensed on the lens. An image reading apparatus comprising: a carriage that can reciprocate in parallel to a document surface, the positioning section positioning the mirror on the carriage body, and the positioning section positioning the mirror on the carriage. An image reading device, wherein a spring member sandwiched between the carriage and the carriage is formed integrally with the carriage body. 2. The image reading apparatus according to claim 1, wherein the carriage body is made of plastic. 3. The carriage according to claim 1, wherein the mirror is fixed to the carriage body by an adhesive.
The image reading device according to any one of the above.