JPH02226768A - Photoelectric conversion device - Google Patents

Abstract

PURPOSE:To increase the freedom of light source arrangement, eliminate the light quantity loss and diffusion of information light, improve the S/N ratio, and increase the sensor output by adopting a structure wherein illuminating light passes the inside of a mounting substrate having light transmitting property. CONSTITUTION:A photo sensor array is formed on a sensor substrate 1 by semiconductor process. Said substrate is composed of quartz glass or borosilicate glass, and has light transmitting property and insulating property. The above array is fixed on a retainer 2 by using silicon system, acryl system, and epoxy system adhesive agent 5. Said retainer is provided with a wiring part 4 of Al, Cu and the like on the surface end-portion, and has the similar light transmitting property and insulating property. A photoelectric conversion device is constituted in this manner, and light L from a light source 3 arranged, e.g. below the retainer 2 is transmitted through the retainer 2 and the sensor substrate 1. A manuscript 6 arranged on the sensor substrate 1 is irradiated with the light L. The light L' reflected from the manuscript 6 is made to enter the array sensor on the substrate 1, and generates an image signal in the photo detectors constituting the array.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a photoelectric conversion device, and is particularly suitable for application to a photoelectric conversion device provided with a photoelectric conversion element (optical sensor) array.

[Prior art] As a method of miniaturizing photoelectric conversion devices, improving yields, and lowering manufacturing costs,
There are those disclosed in No. 0-132452 and Japanese Patent Application Laid-Open No. 62-97370. These disclose a configuration in which a sensor substrate provided with an optical sensor is supported on a support (hereinafter referred to as a mounting substrate) prepared in another process.

[Problems to be Solved by the Invention] However, these conventional examples have the following problems.

First, in JP-A-60-132452, a thick film circuit as a drive circuit is formed on an insulating ceramic substrate as a mounting board, an optical sensor array part is fixed on the mounting board, and the thick film circuit is A configuration is shown in which the optical sensor array section and the optical sensor array section are connected by a wire bonding method. However, in this configuration, since the mounting board is non-light-transmitting, the arrangement of the light source is restricted, and there is a possibility that sufficient miniaturization cannot be achieved.

On the other hand, in Japanese Patent Application Laid-Open No. 62-97370, a light-transmitting sensor substrate on which an optical sensor array is formed is
A configuration is shown in which the sensor is fixed on a light-transmitting mounting board and a non-light-transmitting resin is molded onto the optical sensor. Information light is received onto the optical sensor via the light-transmitting mounting board and the light-transmitting sensor board, and a light shielding plate is provided on the surface of the light-transmitting mounting board to prevent unnecessary light from entering. However, in this configuration, the information light from the document surface passes through the translucent mounting board and the translucent sensor board and enters the light receiving element (optical sensor). The arrival path becomes longer and light intensity loss is more likely to occur.
In addition, stray light components are generated due to diffused light in each layer,
There was a risk that the S/N ratio would decrease and the sensor output would decrease.

By the way, if the light source of the photoelectric conversion device has uneven light intensity,
Variations may occur in the output signal of the sensor, and in some cases, white or black stripes may appear, leading to reading errors. As a technique to improve this, for example, Japanese Patent Application Laid-Open No. 1983-1999
There is one disclosed in No. 310262. This is a configuration in which a light control member (lighting curtain) is provided in the optical path between the light source and the document. This lighting curtain has the form of a light-shielding film provided on the film in a pattern that maintains a constant light intensity distribution, and thereby corrects the illumination light so that it has a uniform distribution on the document surface. Ru.

However, in this conventional example, since the lighting curtain is provided as a separate member, there is a risk that alignment accuracy between the lighting curtain and the light source cannot be ensured, and the provision of the separate member also increases costs.

[Means for Solving the Problems] The present invention aims to solve these problems, and for this purpose, a photoelectric conversion element is provided on the side facing the original for reading image information, and a light-transmitting element is provided. at least a wiring member for connecting a photoelectric conversion element and a circuit for driving the same on the supporting surface of the substrate, the support body supporting the substrate and having a light-transmitting property, and the wiring member thereof. A support body having a light control part partially formed using the same material, and a light source provided on the side of the support body opposite to the support surface of the substrate, and the light emitted from the light source is transmitted to the support body. , the light is irradiated onto the document through the light control unit and the substrate, and the reflected light is received by the photoelectric conversion element.

[Function] According to the present invention, since the illumination light is transmitted through the transparent mounting board (support body), the degree of freedom in arranging the light source is improved and miniaturization is possible. Since the structure is such that the reflected light (reflected light from It also improves. In the present invention, since the illumination light is configured to pass through the board and the mounting board, the illumination light can be applied to the document without adversely affecting each sensor due to appropriate light loss and diffusion when the illumination light passes through. Provides uniform lighting.

In addition, by forming the light control section, which was previously a separate component, at least in part using the same material as the wiring component, both can be formed on the mounting board in the same process, making it possible to reduce the size and cost. Become.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a sectional view of an embodiment of a photoelectric conversion device to which the present invention can be applied. Here, the light-transmitting sensor substrate 1 has an optical sensor array formed by a semiconductor process or the like on a light-transmitting and insulating substrate such as quartz glass or borosilicate glass. The translucent mounting board 2 is made of a transparent material such as quartz glass, borosilicate glass, soda glass, or acrylic (it may be provided with a protective film such as Sin to prevent elution and diffusion of alkali elements). Ag, ^g-P formed by thick film printing on a substrate with optical and insulating properties
It has a wiring part 4 made of d, g-Pt, Au, etc., or Al1, Cu, MojTO, etc. formed by photolithography. Further, as will be described later with reference to FIGS. 5 and 6, a light control pattern is formed on the substrate 2. Note that the base bodies of these substrates 1.2 have similar thermal expansion coefficients.

The wiring section 4 connects the sensor section and a drive circuit section (not shown). Then, the light-transmitting sensor substrate 1 is bonded onto the light-transmitting mounting board 2 using the adhesive layer 5. For this adhesive layer 5, a room temperature or heat curing type, light curing, or other transparent adhesive such as silicone, acrylic, or epoxy type is preferably used. A material whose thermal expansion coefficient and optical refractive index are similar to those of each substrate is used.

Further, the light-transmitting sensor substrate 1 and the wiring portion 4 of the light-transmitting mounting board 2 are electrically connected by wire bonding, soldering, or the like.

The illumination light from the light source 3 is transmitted through the transparent mounting board 2 and the transparent sensor board l, and is irradiated onto the original 6.
Information light reflected from the original 6 enters the light receiving element on the light-transmitting sensor substrate 1, and is outputted from the light receiving element as an image signal.

According to this example, the information light is transmitted to the mounting board 2 and the sensor board 1.
Since the light is received by the optical sensor without passing through the light, there is no reduction in the S/N ratio due to light loss or stray light components. In addition, according to this example, the translucent sensor board l and the translucent mounting board 2 can be handled as independent components, that is, they can be manufactured in separate processes, thus unifying the manufacturing process. It becomes possible to use only non-defective products in each separate inspection process, and the overall yield improves. In addition, since only the optical sensor section is arranged on the base of the substrate 1, it is possible to manufacture a large number of substrates 1 at once using a base material having a certain extent, which makes it possible to reduce costs. Further, it is also possible to mount a driving IC chip, an output amplification IC chip, etc. in addition to the wiring section 4 on the transparent mounting board 2, and in that case, further cost reduction becomes possible. moreover,
By arranging the light source 3 on the back side of the translucent mounting board 2, the external dimensions of the unit can be further reduced.

In other words, according to this embodiment, since the illumination light is transmitted through the light-transmitting mounting board, the degree of freedom in arranging the light source is improved, that is, the light source is placed on the back side of the light-transmitting mounting board. This makes it possible to achieve further miniaturization of devices to which the photoelectric conversion device is applied.

In addition, since the information light does not pass through the light-transmitting mounting board or the light-transmitting sensor board, there is no light loss or diffusion of the information light, and the S/N ratio is improved and the sensor output is also good. becomes.

Furthermore, by using a base made of a material whose thermal expansion (number) is similar to that of the translucent mounting board and the translucent sensor board, it is possible to alleviate the stress caused by bonding the two, which prevents warping and cracking of the board. It's hard to do.

In addition, by providing the wiring section on the translucent mounting board, miniaturization of the device is achieved, and by providing the wiring section between the translucent mounting board and the translucent sensor board, further Downsizing is also possible.

FIGS. 2(^) and 2(B) are an exploded perspective view and a cross-sectional view, respectively, showing another embodiment of a photoelectric conversion device to which the present invention is applicable. This example is an example in which a light-shielding layer 7 is provided between a light-transmitting mounting board 2 and a light-transmitting sensor board 1.

Here, the light-shielding layer 7 is arranged around the slit-shaped window part 7^ that is appropriately defined according to the optical path, and can be formed using the same process and the same metal material as the wiring part 4. Alternatively, it may be formed using a non-transparent resin by a screen printing method, a dispensing method, or the like. Further, the light-shielding layer 7 may be formed by using a non-light-transmitting adhesive for bonding the light-transmitting mounting board 2 and the light-transmitting sensor board 1 (5). In this case, a step of interposing a separate adhesive is performed. becomes unnecessary.

The light-shielding layer 7 created in this manner is formed in a portion of the transparent mounting board 2 excluding the optical path of the illumination light, and has a shape having a slit window portion 7A for light incidence.
This slit-like window portion may be left as a void, or may be filled with transparent resin. In addition, the window portion 7^ on the mounting board 2
A dimming pattern portion is formed in a portion corresponding to the pattern as will be described later with reference to FIGS. 5 and 6.

In any case, according to the configuration shown in FIG. 2, in addition to obtaining the same effect as that shown in FIG.
By blocking stray light that would cause noise in the signal output from the illumination light from the light source, for example, a diffusely reflected component on the translucent mounting board 2, the resolution of the output signal can be improved.

FIG. 3 shows a more detailed cross-sectional structure of the photoelectric conversion device according to the embodiment shown in FIG. 1 or 2. FIG.

Here, a matrix wiring section 9, an illumination window 10, a light receiving element 11
, a charge storage section (capacitor section) 12, and a switching thin film transistor (TPT) 13 for transferring the accumulated charges at appropriate timing.

The light-transmitting sensor board 1 configured in this manner is supported on the light-transmitting mounting board 2 via the adhesive layer 5 or the light-shielding layer 7 (the optical path portion is the window 7A).

All of these parts can be formed using the same manufacturing process. The layer structure of each part is such that, for example, Cr is formed on the substrate, the light-shielding layer lower electrode 15 of the sensor part, silicon hydrogen nitride (SiNx: tl
) with an insulating layer of hydrogenated amorphous silicon on top (
a-5i:H) semiconductor layer. Its upper part n”a-5i
:) Ohmic layer of I, further placed on top of it ^1
It consists of an upper electrode, etc.

The optical sensor section having such a configuration has a passivation layer 19.
Further, on this passivation layer 19, a thin plate glass 14 having a thickness of, for example, 50 μm is placed via an adhesive layer 20.
will be provided. The original slides on this thin glass 14, and the thin glass 14 functions as a spacer layer that keeps the distance between the light receiving element 11 and the original 6 constant, and also functions as a wear-resistant layer.

In this configuration, the illumination light emitted from the back side of the translucent mounting board 2 passes through the translucent mounting board 2 and the translucent sensor board 1, passes through the illumination window 10, and reaches the surface of the thin glass 14. The original 6 is illuminated. Then, the information light L' reflected by the original 6 enters the light receiving element 11.

FIG. 4 is an exploded perspective view showing a configuration in which the photoelectric conversion device having the above-mentioned basic configuration is unitized.

5(^) is a plan view of the sensor unit, FIG. 5(B) is a side view thereof, FIG. 5(C) is a back view thereof, and FIG. 5(D) is a same D-[) 'Line cross section,
FIG. 3(E) is a sectional view taken along the line E-ε'. In the illustrated example, a translucent sensor board 1 is adhesively fixed onto a translucent mounting board 2, and this translucent mounting board 2 is attached to a base plate 2.
2 and further press down with the IC cover 23. Next, the light source 3 is fixed to the lower surface of the pace plate 22. and,
From the unit, flexible wiring 24 and connector 2
An image signal can be output via 5.

FIGS. 6(A) and 6(B) show an example of a dimming pattern section applicable to the configurations shown in FIGS. 1 and 2. In this example, the dimming pattern 26A is formed in the dimming pattern forming part 26 using the same material in the optical path of the illumination light on the translucent mounting board 2 at the same time as the process of creating the wiring part 4. This light control pattern section 26 is AIL.

The light source 3 (LE
The density, size, pitch, etc. of the pattern are appropriately determined in accordance with the variation in the light amount of D, Xe tubes, fluorescent tubes, EL, etc.), and the illuminance distribution on the document surface is made uniform.

FIGS. 7(A) and 7(B) show other examples of dimming patterns. In this example, the wiring section 4 on the translucent mounting board 2 is configured to cross the optical path of the illumination light, and the optical path portion of the wiring section 4 is formed into a dimming pattern 46 whose line width is determined according to the light intensity distribution of the light source. Form. Furthermore, a dimming pattern 27, which is a dummy wiring pattern, is formed in the optical path section other than the dimming pattern part 46 formed by the wiring part 4.

FIG. 8 shows the light amount distribution when a dimming pattern as shown in FIG. 6 or 7 is formed (after shading) and when it is not provided (before shading).

As is clear from the figure, when the dimming pattern was applied, a good and uniform light amount distribution was obtained over the arrangement range of the photoelectric conversion elements (sensor bits). Therefore, the surface of the document is illuminated with uniform illumination light, resulting in a good read image.

Furthermore, the sensor unit 1 configured as described above
00 can be used to configure facsimile machines, image readers, and various other devices.

FIG. 9 shows an example of an image processing apparatus (for example, a facsimile) configured using the sensor unit 100 according to this embodiment.

Here, 102 is a feeding roller for feeding the original 6 toward the reading position, and 104 is a separation piece for reliably separating and feeding the original 6 one by one. A platen roller 106 is provided at a reading position facing the sensor unit 100 to regulate the surface to be read of the original g46 and convey the original fA 6.

P is a recording medium in the form of roll paper in the illustrated example,
Image information read by the sensor unit 100 or, in the case of a facsimile machine, image information transmitted from the outside is formed. Reference numeral 110 is a recording head for forming the image, and various types such as a thermal head and an inkjet recording head can be used. Further, this recording head may be of a serial type or a line type. Reference numeral 112 denotes a platen roller that transports the recording medium P to the recording position by the recording head 110 and regulates the recording surface thereof.

Reference numeral 120 denotes an operation panel equipped with switches for receiving operation inputs, a display section for notifying messages and other device statuses, and the like. Reference numeral 130 denotes a system control board, which is provided with a control section for controlling each section, a processing section for image information of the optical sensor drive circuit section 1, a transmitting/receiving section, and the like. 140 is a power source for the device.

In the embodiments described above, a configuration was described in which the document is read in close contact with or in close proximity to the photoelectric conversion device and the document 6 without interposing an optical system between the photoelectric conversion device and the document 6. The present invention can also be effectively applied to a configuration in which an image of light (light) is formed on a light receiving element via an optical system.

That is, as shown in FIG.
The present invention can be easily applied even to a configuration in which an optical system member 8 such as a converging light transmitting body array or a fiber plate is used between the document 6 and the document 6.

[Effects of the Invention] As explained above, according to the present invention, according to this embodiment, the illumination light is transmitted through the mounting board having translucency, so the degree of freedom in arranging the light source is improved. In other words, it becomes possible to arrange the light source on the back side of the light-transmitting mounting board, and further miniaturization of the device to which the photoelectric conversion device is applied can be achieved.

In addition, since the information light does not pass through the light-transmitting mounting board or the light-transmitting sensor board, there is no light loss or diffusion of the information light, and the S/N ratio is improved and the sensor output is also good. becomes.

Furthermore, according to the present invention, the dimming pattern section is formed on the transparent mounting board using the same process and the same material as, for example, the lighting section, so there is no need to provide a separate lighting curtain. Furthermore, since there is no need for an assembly process, the device can be made smaller and has a lower melting point.

In addition, since the dimming pattern section on the light-transmitting mounting board can be formed from the wiring section itself, further miniaturization is possible, and the degree of freedom in design, such as the arrangement of IC chips, is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view of a photoelectric conversion device according to one embodiment of the present invention, and FIGS. 2 (^) and (B) are exploded perspective views of photoelectric conversion devices according to other embodiments of the present invention, respectively. 3 is a more detailed sectional view of the photoelectric conversion device according to the embodiment of FIG. 1 or 2 (^), (B), and FIG. 5 (^), (B), (C), (D) and (E) are respectively a plan view, a side view, and an rA cross section of the sensor unit. Figure D-D line sectional view and E-E'
The line sectional view and FIGS. 6(A) and 6(B) are an exploded perspective view of a photoelectric conversion device and a plan view of a mounting board, respectively, to show an example of a dimming pattern according to the main part of the present invention. FIGS. 7(A) and (B) are an exploded perspective view of a photoelectric conversion device and a plan view of a mounting board to show other examples of dimming patterns, respectively, and FIG. 8 is whether or not a dimming pattern is formed. FIG. 9 is a cross-sectional view showing an example of an image processing apparatus to which the present invention can be applied; FIG. 10 is a schematic cross-sectional view showing still another embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Translucent sensor board, 2... Transparent mounting board (support body), 3... Light source, 4... Wiring section, 5... Adhesive layer, 6... Document, 7... Light shielding layer, 7^... Window section, 8... Optical system member, 26... Light control pattern forming section, 268, 46.27... Light control pattern. Figure 2 (B) Figure 5 (E) Figure (A) Figure (B) Figure 1 (B) Figure 1θ

Claims (1)

[Claims] 1) A substrate having a light-transmitting property and having a photoelectric conversion element provided on the side facing the original for reading image information, and a support having a light-transmitting property that supports the substrate. A wiring member for connecting the photoelectric conversion element and a circuit for driving the photoelectric conversion element and a light control part formed using at least a part of the same material as the wiring member are provided on the support surface of the substrate. and a light source provided on a side of the support opposite to the support surface of the substrate, wherein light emitted from the light source passes through the support, the light control unit, and the substrate. A photoelectric conversion device characterized in that the reflected light is irradiated onto the document and the reflected light is received by the photoelectric conversion element. 2) The photoelectric conversion device according to claim 1, wherein the light control section is patterned in the same process as the wiring member. 3) The photoelectric conversion device according to claim 2, wherein at least a part of the wiring member is also used as the light control section. 4) The photoelectric conversion device according to claim 1, wherein the light control section is formed in a pattern that equalizes variations in the amount of light.