JP2872488B2 - Contact image sensor and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a contact type image sensor used for an image information processing apparatus such as a facsimile, an image reader, and a copying machine, and a method of manufacturing the same, and particularly relates to a structure of a support.

[0002]

2. Description of the Related Art Conventionally, a sensor array for performing photoelectric conversion, an imaging element for forming light from a document on the sensor array, a member for defining a reading surface of the document, and a light source for illuminating the document. And a close contact type image sensor having a support for supporting the above.

[0003] Such an image sensor is described in "Image Reading Apparatus with Image Prevention Function (Image Reading Apparatus)" given to the inventor Kokura et al.
with Jam-Prevention Feature
re)), U.S. Pat. No. 4,920,431, entitled "Image Reading Method and Apparatus (Method and Apparatus)"
US Patent No. 4,680,644 entitled "For Readingan Image" and "Method of Manufacturing Optical Sensor (Method)" given to Fukaya et al.
of Manufacturing Photose
U.S. Patent No. 4,792,6, entitled "
No. 70, etc.

FIG. 1 is a schematic perspective view showing the appearance of a conventional image sensor. 1 is a frame as a support,
Reference numeral 5 denotes a glass as a transparent member which can come in contact with the original and defines a reading surface thereof, and 10 denotes a side plate. Many optical sensors (pixels) are arranged in the longitudinal direction (main scanning direction) DM of the support, and the lateral direction DS is the sub-scanning direction.

FIG. 2 shows a section taken along the line AA 'in FIG. An imaging element 7 is arranged in a first space 1A of the support 1, and a light source 9 is arranged in a second space 1B. These first and second spaces communicate with each other. The sensor array 3 is provided on a substrate 4 and is covered with a protective layer 33. The sensor array 3 is arranged between the frame 1 and the second frame 2 toward the third space 1C.

[0006] The method of assembling such an image sensor is performed as follows. That is, the light source 9 is fixed to the mounting surface 19 of the frame 1 with an adhesive or a screw, and the substrate 4 on which the sensor array 3 is provided is fixed to the frame 1 by the second frame 2. Then, the imaging element 7 is moved to the space 1
A, fix it with screws 17, fix the glass 5, and attach the side plate 10.

FIG. 3 is a schematic sectional view showing another conventional example.

An image sensor 7, a light source 9, and a sensor array 3 are mounted on a support 1 of the image sensor shown in FIG. 3, similarly to the image sensor shown in FIG. Covered. In this configuration, a plate-like member that defines the document surface is used instead of the glass.

(Technical Problems to be Solved by the Invention) However, the above-described conventional example has the following technical problems to be solved. At the time of mounting each component, the light source 9 was mounted from above the frame 1, the lens 7 was mounted from above and beside the frame 1, and the sensor array 3 was mounted from below the frame 1. The workability was bad. In addition, at the time of mounting, the worker mounts the light source, the lens, and the sensor array while turning the frame 1 upside down on the worktable.
Garbage often entered A, 1B and 1C.

The optical positioning of each component is performed by the frame 1.
However, the technology for processing aluminum, which is a constituent material of the frame, was unable to respond to the positioning accuracy, resulting in even more difficult positioning.

(Object) It is an object of the present invention to provide a contact type image sensor having a structure in which each component can be easily attached and processed.

Another object of the present invention is to provide a contact type image sensor having a structure in which positioning of each component with respect to a support can be easily and accurately performed.

An object of the present invention is to provide a sensor array for performing photoelectric conversion, an imaging element for forming an image of light from a document on the sensor array, a transparent member for defining a reading surface of the document, and an object for illuminating the document. A light source, and a support member for supporting the light source, wherein the support member has a first support member having a positioning portion for determining positions of the light source, the imaging element, and the sensor array. And a second support member having two opposing portions in the longitudinal direction and an intersecting portion intersecting the opposing portion, wherein the second support member connects the first support member with the opposing portion. A contact type image sensor, wherein the image forming element is interposed therebetween and the transparent member is interposed therebetween, and the first support member and the sensor array are interposed between the transparent member and the intersection. Yo It is achieved.

A further object of the present invention is to provide a sensor array for performing photoelectric conversion, an imaging element for forming an image of light from a document on the sensor array, a transparent member for defining a reading surface of the document,
A light source for illuminating a document; and a first support having a positioning unit for determining positions of the light source, the imaging element, and the sensor array.
And a second support member having two opposed portions in the longitudinal direction and an intersecting portion intersecting the opposed portion, wherein the second support member is provided by the first portion by the opposed portion.
Wherein the imaging element is sandwiched via the supporting member and the transparent member is sandwiched, and the first supporting member and the sensor array are sandwiched between the transparent member and the intersection. An image information processing apparatus having a type image sensor, wherein the second support member is provided with a mounting portion, and the second supporting member is mounted to the device main body by the mounting portion.

Still another object of the present invention is to provide a sensor array for performing photoelectric conversion, an imaging element for forming light from a document on the sensor array, a transparent member for defining a reading surface of the document, and an illumination of the document. A method for manufacturing a contact-type image sensor, comprising: a light source for supporting the light source; and a support member having a positioning portion for determining positions of the light source, the imaging element, and the sensor array. Into a second support member having two longitudinally opposed portions and an intersecting portion that intersects the opposed portion, and the light source and the first support member incorporated into the second support member. Attaching the imaging element, holding the transparent member between the opposed portions, and arranging and fixing the transparent member on the light source and the imaging element attached to the first support member. Feature It is achieved by the method for producing a contact type image sensor for.

[0016]

According to the present invention, the support is functionally separated into a first support member requiring high precision processing and a second support member requiring high strength, thereby providing a low cost and high quality. An image sensor can be provided.

Also, by mounting the first supporting member on the second supporting member and then attaching the optical components from the same direction, it is possible to provide an image sensor which does not cause a malfunction by a simple operation.

(Explanation of the Preferred Embodiment) Hereinafter, the preferred embodiment of the present invention will be described, but the present invention is not limited to this, and may be any configuration that achieves the object of the present invention. .

FIG. 4 is a schematic perspective view showing a contact type image sensor according to the present embodiment, and FIG.
It is sectional drawing by the B 'line.

A first frame 1 made of a molding resin having a matte surface as a support is provided with a sensor array 3 and a sensor substrate 4 as components, a lens 7 as an imaging element, and a light source 9. Positioning unit 1 to be arranged at a predetermined position
3, 17, and 19 are provided. The first frame 1 is sandwiched between the second frame 2 as a support and the transparent member 5 in the y direction in FIG.
, The position of the light source 9 and the lens 7 in the y direction are determined. That is, the sensor array 3 is sandwiched between the bottom surface (intersecting portion) 22C of the second frame 2 and the bottom surface 13 which is a positioning portion of the first frame 1, and the light source 9 is connected to the back surface 15 of the transparent member 5.
The lens 7 is also held between the back surface 15 of the transparent member and the positioning unit 17. The second frame 2 as a support is made of processed aluminum having a U-shaped cross section. In the x direction, the position of the second frame 2 is determined by the side surfaces 22A and 22B of the second frame 2 sandwiching the lens 7 with the first frame 1 interposed therebetween. The substrate 4 of the sensor array 3 is also positioned by both side portions 22A and 22B of the second frame 2 and the positioning projections 2B of the first frame. Similarly, the transparent member 5 is also held by both side portions 22A and 22B of the second frame 2. Here, “positioning” has a relative meaning similar to the action / reaction in dynamics.
"The transparent member 5 determines the position of the lens 7 while the lens 7
The positioning of the transparent member 5 is performed ".

In this embodiment, the LED array 9 and the lens 7
Is brought into contact with the transparent body 5 to prevent the foreign matter from moving into the optical path, and the contact type image sensor can be assembled by a simple operation.

In the present invention, as the first frame 1, a member capable of providing a highly accurate reference surface for positioning the optical component is preferably used. In particular, it is preferable to use a resin. Resin is injection molded.
Since very high precision part molding can be performed in a simple process, it can be produced at low cost in addition to the conventional Al processing. In addition, as shown in FIGS. 10 to 12, the configuration in which the cross-sectional shapes of the end portion and the central portion are different can be easily formed by using a molding resin. Further, since the frame itself can be subjected to color processing such as black or brown, a frame having a light blocking function can be provided. In addition, it is possible to easily form a matte surface composed of fine irregularities.

As the second frame 2 of the present invention, a material having higher rigidity than the first frame is used. Specifically, a rigid body made of a metal such as stainless steel, aluminum, or copper is preferably used.

Deformation due to thermal expansion due to a difference in materials combined as the first frame and the second frame may be particularly problematic in the longitudinal direction of the image sensor. Since the positioning in the longitudinal direction is performed by the fitting structure at one central portion, there is no adverse effect due to deformation.

In addition, by using the opening of the second frame having a U-shaped cross section, the first frame and each optical component can be incorporated from one direction, so that the assembling work is simplified.

Among the optical components according to the present invention, an element for forming an erect image of the same magnification is preferably used as the image forming element, but the present invention is not limited to this, and various lenses, optical fibers and the like can be used. .

As the light source among the optical components, a xenon discharge tube or the like can be used in addition to the LED array that generates red, green, and yellow light.

The sensor array 3 of the optical components
U.S. Pat.
A long optical sensor using amorphous silicon as described in the specification of Japanese Patent No. 61,956 is preferable because of its low cost and high resolution.

Further, it is described in US Pat. No. 4,791,469 assigned to the inventor Omi et al. And US Pat. No. 4,810,896 assigned to the inventor Tanaka et al. An optical sensor of a type in which a capacitive load is provided on the emitter of such a bipolar transistor and an output signal is read out from the emitter as a voltage is also more preferably used.

(Assembling Method) The image sensor is assembled as shown in FIG. First, prepare each part. For example, the second frame 2 has a screw hole 2 as an attachment means for attaching the image sensor to the apparatus main body side.
A, a positioning projection 2B for positioning the sensor substrate 4 in the x direction, a positioning projection 2C for positioning the sensor substrate 4 in the z direction, and positioning of the first frame 1 in the z direction. And a positioning portion 2D. These are formed by sheet metal bending, drawing, embossing, or the like.

The sensor substrate 4 is provided on the bottom of the second frame 2.
Place. Here, the positioning in the x direction and the z direction is performed by the positioning units 2B and 2C. At this time, a connector 50 for exchanging signals with the outside and the apparatus body is connected to the sensor board 4 by a flexible wiring 51.

Next, the first frame 1 is fitted into the recess of the second frame 2. At this time, the positioning in the z direction is performed by the groove 2D provided in the center of the second frame and the projection 1H that can be fitted in this groove. The positioning in the x direction is performed by the side walls 22A and 22B of the second frame 2. The light source 9 is located at a predetermined position in the first frame 1.
And the lens 7 are arranged. Finally, a glass plate 5 as a transparent member is fitted to the ends of both side walls of the second frame. In this manner, the light source 9, the lens 7, and the sensor array 3 of the first frame 1 are positioned in the y direction.

The contact type image sensor thus obtained is screwed to a main body of an image information processing apparatus as will be described later by using a mounting portion of the second frame 2.

Next, with reference to FIGS. 7, 8 and 9, the operation and effect of this embodiment will be described. FIG. 7 shows only the transparent body 5, the first frame 1, and the second frame 2.

Since the first frame 1 is formed using a material that is slightly deformed, distortions such as a warp 1D in the x direction and a warp 1E in the y direction occur. However, since the first frame 1 is fitted in the second frame 2 made of a material having relatively high rigidity, such distortion is corrected, and a lens as an image forming element and an LED array as a light source are formed. The placement is determined correctly. High-precision positioning of the imaging element and the light source is performed by the first frame 1. As shown in FIG. 8, in optical positioning, the distance 1F between the sensor and the light exit surface of the lens and the distance 1G between the sensor and the light entrance surface of the lens in FIG. 8 are important. The accuracy is determined by the first frame 1.

FIG. 9 shows how the sensor substrate 4 is positioned on the xz plane in the second frame 2.

In the second frame 2, the sensor substrate 4 is positioned in the x direction by a side wall portion 22A formed by bending a sheet metal and a positioning portion 2B formed by drawing. On the other hand, by providing the projections 2C by embossing at both ends of the second frame 2, the sensor substrate 4 is positioned in the z direction.

FIG. 10 shows an end portion of the image sensor of this embodiment. FIG. 11 shows a cross section taken along line CC 'in FIG.
FIG. 12 shows a cross section taken along line DD 'in FIG.

As can be seen from these figures, by making the outer peripheral shape of the first frame 1 and the inner peripheral shape of the second frame 2 identical at both ends of the image sensor, the formation of a gap is hindered and foreign matter and stray light are prevented. To prevent intrusion.

Further, in the present embodiment, the length (z direction) of the lens 7 accommodating portion of the first frame 1 is determined from the length (z direction) of the lens 7.
Direction) by increasing the clearance
A is provided. Further, by making the length of the slit 8 (z direction) smaller than the length of the lens 7, the length (z direction) 7B of the contact portion between the lens 7 and the first frame is provided. The clearance 7A is smaller than the length 7B. The length of the sensor array 3 (z direction) is smaller than the length of the slit 8 and the length of the sensor substrate 4 is increased. By preventing light from transmitting through the end of the lens 7 outside the sensor array, it is possible to prevent stray light from entering.

The image sensor of this embodiment will be described again. FIG. 13 is an equivalent circuit diagram corresponding to the one pixel.

[0042] PS is a bipolar transistor, SW ₁ is NMOS transistor, SW ₂ as a switch means for resetting an emitter connected to a reference voltage source V _ES for forming a pixel is a base connected to a reference voltage source V _BB A PMOS transistor as a switch means for performing a reset, and SW ₃ is an N-type transistor as a switch means for transferring a signal charge.
The MOS transistor, CT, is a quantitative load for generating a signal voltage. The operation will be briefly described.

[0043] <Reset Operation> First PMOS transistor SW ₂ negative pulse voltage is applied to the gate of the base is clamped to the voltage V _BB.

[0044] is then applied positive pulse voltage to the gate of the NMOS transistor SW ₁ is emitter connected to a voltage source V _ES, a current flows between the base and emitter, the photogenerated carriers disappear remaining in the base .

<Storage operation> NMOS transistor SW
_1, SW ₃ both emitter turned off, is a floating state in the base both accumulation operation is started.

[0046] <reading operation> Next NMOS gate of the transistor SW ₃ positive pulse voltage is applied is turned on,
When the emitter and the capacitor CT are connected, the signal voltage is
Is read out.

The basic structure of such an image sensor is disclosed in US Pat.
86,554 and the like describe a charge storage type high-sensitivity, low-noise photoelectric conversion device in which an emitter of a bipolar transistor is connected to an output circuit including a capacitive load.

While the charge storage / amplification type image sensor using bipolar transistors has been described above, the present invention employs a type in which a photodiode is used as a light receiving portion and a signal charge is transferred by a MOS switch, a charge-coupled device (CCD), or the like. It is preferably applicable to sensors.

FIG. 14 shows an example of a facsimile having a communication function as an image information processing apparatus constituted by using the sensor unit according to the present embodiment. Here, reference numeral 102 denotes the document PP
A feeding roller 104 as a feeding unit for feeding the document PP toward the reading position is a separation piece for reliably separating and feeding the document PP one by one. Reference numeral 106 denotes a platen roller which is provided at a reading position with respect to the sensor unit, regulates the surface to be read of the document PP, and serves as a transport unit for transporting the document PP.

P is a recording medium in the form of a roll paper in the example shown in the figure, and the image information read by the sensor unit or, in the case of a facsimile machine or the like, the image information transmitted from the outside is reproduced here. Reference numeral 110 denotes a recording head as recording means for performing the image formation, and various types such as a thermal head and an ink jet recording head can be used. The recording head may be of a serial type or a line type. 11
A platen roller 2 conveys the recording medium P to the recording position of the recording head 110 and regulates the recording surface.

Reference numeral 120 denotes an operation panel provided with switches and messages for accepting operation inputs as input / output means, and a display unit for notifying the status of the apparatus.

Reference numeral 130 denotes a system control board as control means, which controls each unit, a drive circuit (driver) for a photoelectric conversion element, a processing unit (processor) for image information, a transmission / reception unit, and the like. Is provided. 140 is a power supply of the apparatus.

As the recording means used in the information processing apparatus of the present invention, it is preferable to use, for example, those disclosed in US Pat. No. 4,723,129 and US Pat. No. 4,740,796, whose typical configuration and principle are disclosed. According to this method, at least one of the electrothermal transducers corresponding to the recorded information and having a rapid temperature rise exceeding the nucleate boiling is applied to the electrothermal transducer disposed corresponding to the sheet or the liquid path holding the liquid (ink). By applying a drive signal, heat energy is generated in the electrothermal transducer, causing the film to boil on the heat-acting surface of the recording head. It is effective because it can be formed. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed.

Further, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, a combination of a plurality of recording heads as disclosed in the above-mentioned specification is used. Either a configuration that satisfies the length or a configuration as one integrally formed recording head may be used.

In addition, a replaceable chip-type recording head which can be electrically connected to the apparatus main body and supplied with ink from the apparatus main body by being attached to the apparatus main body, or the ink is supplied to the recording head itself. The present invention is also effective when a cartridge type recording head having an integrated tank is used.

[0056]

According to the present invention, the first support member, which is relatively easy to perform high-precision processing for positioning, and the second support member, which is relatively difficult to perform high-precision processing but is excellent in strength, are provided. By using the supporting member, each optical component can be attached with high accuracy and simple operation, and the production of the contact image sensor and the image information processing apparatus can be performed at low cost.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a conventional contact image sensor.

FIG. 2 is a cross-sectional view taken along line AA ′ of FIG.

FIG. 3 is a schematic sectional view of another example of a conventional contact image sensor.

FIG. 4 is a schematic perspective view of a contact image sensor according to an embodiment of the present invention.

FIG. 5 is a sectional view taken along the line BB ′ in FIG. 4;

FIG. 6 is a schematic view for explaining a method of manufacturing a contact image sensor according to an embodiment of the present invention.

FIG. 7 is a schematic diagram illustrating an image sensor according to an embodiment of the present invention.

FIG. 8 is a schematic diagram illustrating an image sensor according to an embodiment of the present invention.

FIG. 9 is a schematic diagram illustrating an image sensor according to an embodiment of the present invention.

FIG. 10 is a schematic diagram for explaining a configuration of an end of an image sensor according to an embodiment of the present invention.

FIG. 11 is a sectional view taken along line CC ′ of FIG. 10;

FIG. 12 is a sectional view taken along line DD ′ of FIG. 10;

FIG. 13 is a circuit diagram of a sensor used in the present invention.

FIG. 14 is a schematic sectional view showing an image information processing apparatus according to one embodiment of the present invention.

Claims (13)

(57) [Claims] 1. A sensor array that performs photoelectric conversion, an imaging element that forms light from a document on the sensor array, a transparent member that defines a reading surface of the document, and a light source for illuminating the document. A contact-type image sensor comprising a support for supporting a first support member having a positioning portion for determining positions of the light source, the imaging element, and the sensor array; and a longitudinal direction. A second support member having two opposing portions and an intersecting portion intersecting with the opposing portion, wherein the second support member is connected by the opposing portions via the first support member. A contact type image sensor, wherein an image element is interposed and the transparent member is interposed, and the first support member and the sensor array are interposed between the transparent member and the intersection. 2. The contact type image sensor according to claim 1, wherein the first support member has a colored satin-like surface. 3. The contact type image sensor according to claim 1, wherein the first support member and the second support member can be assembled from only one direction. 4. The apparatus according to claim 1, wherein the second support member is provided with a mounting portion for mounting to the apparatus main body and a positioning portion for positioning the first support member. 2. The contact type image sensor according to 1. 5. The second support member has a U-shaped cross section, and at least one of the opposing portions is provided with a positioning groove or projection, and the first support member has the groove or projection. The contact type image sensor according to claim 1, wherein a protrusion or a groove that engages with the protrusion is provided. 6. An apparatus according to claim 1, wherein the outer peripheral surfaces of both ends in the longitudinal direction of the first support member and the inner peripheral surface in the longitudinal direction of the second support member have substantially the same shape. The contact image sensor described. 7. The contact-type image sensor according to claim 1, wherein the sensor array has a circuit for reading a signal to a capacitive load connected to an emitter of the bipolar transistor. 8. The contact image sensor according to claim 1, wherein the sensor array has a photoelectric conversion layer made of amorphous silicon. 9. A sensor array that performs photoelectric conversion, an imaging element that forms light from a document on the sensor array, a transparent member that defines a reading surface of the document, and a light source for illuminating the document. A first support member having a positioning portion for determining the positions of the light source, the imaging element, and the sensor array, and two opposing portions in the longitudinal direction. And a second support member having an intersecting portion intersecting the opposing portion, wherein the second supporting member sandwiches the imaging element with the opposing portion via the first supporting member. Together with the transparent member,
An image information processing apparatus having a contact-type image sensor, wherein the first support member and the sensor array are sandwiched between the transparent member and the crossing portion, wherein the image sensor is attached to the second support member. An image information processing apparatus, comprising: a mounting section; 10. The image information processing apparatus according to claim 9, further comprising a recording head for recording an image.
An image information processing apparatus according to claim 1. 11. The image information processing apparatus according to claim 10, wherein the printhead is an ink jet printhead that discharges ink using thermal energy. 12. The method according to claim 9, wherein the image forming apparatus is attached to the apparatus main body by an attaching section provided on the second support member. 13. A sensor array that performs photoelectric conversion, an imaging element that forms light from a document on the sensor array, a transparent member that defines a reading surface of the document, and a light source for illuminating the document. In a method for manufacturing a contact type image sensor including a support for supporting a light source, a first support member having a positioning portion for determining a position of the light source, the imaging element, and the sensor array is disposed in the longitudinal direction by 2 mm. The light source and the imaging element on the first support member incorporated in the second support member having two opposed portions and an intersecting portion intersecting the opposed portion. Mounting, wherein the transparent member is sandwiched between the opposed portions, and the transparent member is arranged and fixed on the light source and the imaging element mounted on the first support member. Manufacturing method of disensor.