JPH05252344A - Image reader/display device - Google Patents

Abstract

PURPOSE:To make it possible to display information and read out a two-dimensional image only by one device. CONSTITUTION:Plural light emitting elements 3 forming light shielding films 4 on their surfaces are two-dimensionally formed on a transparent base 2 to form a display part 1. On the other hand, plural light receiving elements 7 are two-dimensionally formed on a base 6 to form an image reading part 5. Each light receiving elements 7 is arranged between two light emitting elements 3. In the case of displaying an image, respective elements 3 are emitted by a display driving circuit based upon a simple matrix system or an active matrix system and the emitted elements 3 are observed from the transparent base (2) side. In the case of reading out an image, an original 13 is set up on the base 2, the elements 7 are driven, the elements 3 adjacent to the elements 7 are simultaneously emitted at the same brightness and reflected light from the original 13 is made incident on the elements 7.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an input / output device for information related equipment such as a computer, and more particularly to an image display / reading device capable of displaying information and reading a two-dimensional image.

[0002]

2. Description of the Related Art Information related equipment is usually equipped with an image display device for displaying information. The image display device includes a CRT, a liquid crystal display device (LCD), an EL display device (ELD), a plasma display device (PDP), and an LED.
Various types of devices such as a display device using a (Light Emitting Diode) are used. Especially, in recent years, with the development of high-density mounting technology, a portable type in which an IC for display drive is mounted on an LCD display substrate. A personal computer, a notebook-sized information processing device, and the like have been developed.

In recent years, many information-related devices have an image input device in addition to the above-described image display device. Therefore, a device in which an image input device is added to the image display device is proposed. Has been done. For example, Japanese Patent Laid-Open No. 62-37729 proposes an image display device to which a light input type light pen is added. In addition, a capacitive coupling type light pen or a resistance type pen touch system is adopted. Is also proposed.

[0004]

However, with the above-described method using the light pen or the pen touch method, only the image drawn by the operator can be input, and the image of the original on which the desired image is drawn cannot be read. there were. Therefore, it is conceivable to combine an image reading device capable of reading a two-dimensional image with a display device, and in fact, it is proposed in JP-A-1-106467 to form a display element and an image reading element on the same substrate. However, in this device, since the display element and the image reading element are formed in different regions, it is necessary to add a lighting device such as a light source, and there is a problem inevitably that the size becomes large. It was

Further, the conventional image reading apparatus is mainly a one-dimensional contact type image sensor, and therefore a driving system for driving an original or an image sensor is required to read a two-dimensional image, and thus it is large in size. Becomes
It is not suitable for portable information-related equipment. On the other hand, it is possible to read a two-dimensional image by performing a sub-scan by a manual operation using a one-dimensional image sensor. According to this, the image reading device can be downsized, and it can be carried by a portable device. Although it is also suitable for an information processing device for use with a mobile phone, there is a problem in that sub-scanning cannot be performed well due to camera shake or the like, and as a result, image reading cannot be performed accurately.

Further, JP-A-53-119619 and JP-A-59
A two-dimensional image sensor has been proposed in Japanese Patent Laid-Open No. 149456 or the like, but there is a problem that it becomes a very large-scale device because an illumination device for moving a light source is required.

The present invention solves the above-mentioned problems and provides an image reading / displaying device capable of not only displaying information but also reading a two-dimensional image and achieving miniaturization. The purpose is that.

Further, according to the present invention, when the two-dimensionally arranged light emitting elements and the two-dimensionally arranged light receiving elements are formed on separate substrates, the drive electrodes of the light emitting elements and the light receiving elements are formed. It is intended to connect to another substrate such as a control substrate with high reliability and to maintain a uniform gap between the substrate on which the light receiving element is formed and the substrate on which the light emitting element is formed. ..

[0009]

When a two-dimensional image sensor is used as an image reading apparatus, an apparatus for driving the image sensor or the original document as in the case of using the one-dimensional image sensor. There is a possibility that the information processing device can be miniaturized because it is not necessary to provide the device, and therefore there is a possibility that the information processing device can be installed in a portable information processing device. Therefore, the problem is how to downsize the device for illuminating the original, but a display in which light emitting elements are two-dimensionally arranged, such as a display device using an ELD, PDP, or LED as a display device, is displayed. In the case of the device, it can be seen that all the light emitting elements can emit light with the same brightness, and thus the display device can be used as a light source when reading an image.

Therefore, the image reading / display apparatus of the present invention is an image in which an image reading section in which light receiving elements are two-dimensionally arranged and a display section in which light emitting elements are two-dimensionally arranged are overlapped. A reading / display device,
The image reading unit side or the display unit side is a document placing surface, and the light receiving element is arranged at a position where light emitted from the light emitting element and reflected by the document can enter. To achieve.

In the image reading / display apparatus of the present invention, when displaying an image, only the display section is driven to display the image as in the conventional display apparatus. The light-emitting elements that constitute the display section emit light with a predetermined brightness and serve as a light source for reading an image.The light emitted from these light-emitting elements is reflected by the document and enters the light-receiving element to read an image. Done.

Therefore, according to the present invention, since the light emitting element forming the display portion is also used as a light source for reading the image of the original, it is not necessary to provide a special light source for reading the image, and the size can be reduced. A completely new image reading /
A display device can be realized.

Further, according to the present invention, by using the flexible printed circuit board, the terminal electrodes of the light emitting element substrate and the light receiving element substrate can be easily connected to the external board such as the control board, and the flexible printed circuit board can be connected. By utilizing the thickness of the circuit board, the gap between the light emitting element substrate and the light receiving element substrate can be easily formed. Further, by interposing a transparent spacer in the gap portion, it is possible to reduce variations in the gap.

[0014]

Embodiments will be described below with reference to the drawings.
FIG. 1 is a sectional view showing a schematic configuration of a first embodiment of an image reading / displaying device according to the present invention. On the transparent substrate 2, a plurality of light emitting elements 3 each having a light shielding film 4 formed thereon are two-dimensionally formed at predetermined intervals to form a display unit 1. Further, a plurality of light receiving elements 7 are two-dimensionally formed on the substrate 6 at predetermined intervals to form an image reading section 5. Then, the display unit 1 and the image reading unit 5 are aligned and fixed to each other so that the light receiving element 7 is located between the light emitting elements.

Here, as the light emitting element 3, any light emitting element capable of displaying an image such as EL and LED and used as a light source for image reading can be used. The light-shielding film 4 is applied to the light emitting element 3
Of course, it can be formed by depositing l, Cr, etc. by a vapor deposition method, a sputtering method, or the like, but the electrode for driving the light emitting element 3 can also be used as the light shielding film 4. That is, for example, when the light emitting element 3 is formed by EL, as shown in FIG. 2, the transparent electrode 2, the insulating layer 9, the light emitting layer 10, the insulating layer 11, and the back electrode 12 made of Al are formed on the transparent substrate 2. The light emitting element 3 including the light shielding film 4 can be formed by stacking the layers in order. Further, the light receiving element 7 may be any one having a photoelectric conversion function, and a photodiode formed of amorphous silicon (hereinafter referred to as a-Si), a photoelectric conversion element such as CdS, CdSe, or the like can be used.

FIG. 3 is a plan view showing a relative positional relationship between the light emitting element 3 and the light receiving element 7. As described above, the light receiving element 7 is arranged between the adjacent light emitting elements. FIG. 3A shows an example in which the light emitting element 3 has 3 × 4 pixels and the light receiving element 7 has 3 × 3 pixels. In FIG. 3B, the light emitting element 3 has 3 × 3 pixels and the light receiving element 7 has 2 pixels.
An example of x2 pixels is shown, and FIG. 6C shows an example of the light emitting element 3 being 3x4 pixels and the light receiving element 7 being 2x2 pixels. In this way, the image reading section including the light receiving element 7 is formed in the area of the display section including the light emitting element 3. This is clear because the display section is used as a light source for image reading during image reading. Therefore, the shape and size of the image reading unit can be arbitrarily determined within the area of the display unit according to the purpose.

Next, a method of driving the display unit 1 and the image reading unit 5 will be described. First, when the image reading / display device is used as an image display device, each light emission is performed by a simple matrix method or an active matrix method by a display drive circuit (not shown in FIG. 1) as in a normal ELD. The element 3 is made to emit light. Therefore, the display image can be observed from the transparent substrate 2 side in FIG.

When used as an image reading apparatus, as shown in FIG. 4, an original 13 is placed on the transparent substrate 2 and an image reading drive circuit (not shown in FIGS. 1 and 4). The light-receiving element 7 is driven by the display driving circuit, and the light-emitting element 3 adjacent to the light-receiving element 7 is simultaneously made to emit light with the same brightness by the display drive circuit. For example, in the configuration of FIG. 3A, 3 × 4
All the light emitting elements 3 of the pixel emit light to function as a light source, and in the configuration of FIG. 3B, all the light emitting elements 3 of 3 × 3 pixels emit light to function as a light source. Further, in the configuration of FIG. 3C. Only the light emitting element 3 of 2 × 3 pixels shown in the broken line emits light and functions as a light source. Then, the light emitted from the light emitting element 3 and reflected by the original 13 is transmitted through the light transmitting portion between the light emitting elements and enters the light receiving element 7. Since the amount of light incident on the light receiving element 7 changes according to the image information of the original document 13, that is, the density of the pixel, an electric signal corresponding to the density of each pixel is obtained from the light receiving element 7, and the image is read by this. Be seen. At this time, it is clear that the light shielding film 4 can prevent the light emitted from the light emitting element 3 from directly entering the light receiving element 7, and can shield the unnecessary incident light from the side portion or the end portion.

In the image reading / display apparatus shown in FIG. 1, the optical light pen 14 as shown in FIG. 5A is used.
It is also possible to input an arbitrary image by directly inputting the light of (3) to the light receiving element 7. Further, as shown in FIG. 9B, the image forming lens 15 may be arranged on the display surface side, and a subject image (not shown) may be formed on the light receiving element 7 by the image forming lens 15 for reading. In any case, the light emitting element 3 may not emit light.

As described above, the light receiving element 7 is arranged between the light emitting element and the light emitting element. At this time, it is important to arrange the light receiving element 7 at a position where light from an adjacent pixel does not enter. is there. That is, if only the reflected light from only the image area corresponding to the light receiving element is incident on the light receiving element 7, the MTF (Modulation Transfer Functio) showing the resolution, which is one of the important characteristics of the reading device, is obtained.
Although n) is improved, the MTF is lowered when the reflected light from the adjacent pixels or other image areas is incident. Therefore, the optimum position for arranging the light receiving element 7 will be described.

Now, as shown in FIG.
Consider two pixels A, B, and C and how the reflected light from these pixels spreads through the light incident window between the light emitting elements 3. In FIG. 6, only the original 13 and the light shielding film 4 are shown for easy understanding.

In FIG. 6A, with respect to the pixel B of the original document 13, the reflected light from the pixel A and the pixel C also leaks through the respective light incident windows in the region below the point x. FIG. 6B is a diagram showing a locus of light when the reflected light from the pixel A and the pixel C spreads through the light incident window corresponding to the pixel B. In this case, the pixel A and the pixel C in the region above the point y. It can be seen that the light from is entering the region directly below the pixel B.

In summary, as shown by the area w in FIG. 6C, it can be seen that the area immediately below the pixel B has an area where neither the reflected light from the pixel A nor the reflected light from the pixel C is incident. 6C, the pixel pitch is a, and the original 1
3 is the distance from the light incident window to b, and the size of the light incident window is c
Then, the distance from the reflecting surface of the document 13 to the point x is 3a.
b / (a + b), and the distance from the reflection surface of the document 13 to the point y is represented by ab / (ac). This size is, for example, when the pixel density is 8 dots / mm, a = 125 μm, b = 100 μm,
If c = 50 μm, x point is about 214 μm and y point is about 167
It will be in the distance of μm. In the area w of FIG. 6C, the position where the influence of the incident light from the adjacent pixels A and C is the least is at the position 2b from the reflecting surface of the document 13, so in this case, the distance is 200 μm.

Therefore, the MTF can be maximized if the light receiving element is arranged in the region w where the light from the pixel B is not affected by the leakage of the light from the pixels A and C.
Since increasing the size of b lowers the MTF, it is desirable to reduce it as much as possible. In the above example, the MTF is 30% or more when the light receiving element is arranged at a distance of 2b from the document surface.

In the above description, the influence of the reflected light from the pixel A and the pixel C has been described. However, since light leaks from a pixel farther than this, when the light incident window is extremely small. Except for, there is no region where there is no leakage of light from other pixels. However, since the amount of light from the distant pixel areas is small, the influence on the MTF is small. In order to completely prevent the leakage of light from the distant pixels, the light receiving element may be arranged below the point y and the thickness of the light shielding film 4 may be equal to b. However, it has been confirmed that light leakage from other pixels can be shielded almost completely by setting the thickness of the light shielding film 4 to about b / 2.

Regarding the size of the light receiving element, it is most preferable if it can be arranged in the region w which is not affected by the leakage of light from the adjacent pixels, but if the size of the light receiving element is reduced, the sensitivity is lowered accordingly. Therefore, it is not always necessary to completely dispose it in the region w, and it may be considered together with the sensitivity within the allowable range of the MTF. However, the distance from the document surface must be between the x point and the y point.

Further, the thickness of the light shielding film 4 is not always b.
It does not have to be thicker than about 1/2,
It may be determined within the allowable range of MTF, and the shape does not need to be thick on the entire surface, and only a part may be thick. By arranging the light receiving element at the optimum position as described above, the MTF can be improved when the image reading / display device is used as an image reading device.

Next, a more detailed structure will be described. The image reading / display device shown in this embodiment can be configured by forming the display unit 1 and the image reading unit 5 on separate substrates and bonding them together, as shown in FIG.
Alternatively, as shown in FIG. 8, the image reading section 5 and the display section 1 may be laminated on one substrate. In FIG. 7, the display unit 1 includes a transparent electrode 25, a transparent electrode 25,
The dielectric layer 26, the light emitting layer 27, the dielectric layer 28, and the drive electrode 29 also serving as a light shielding film are sequentially laminated. It will be apparent to those skilled in the art that each layer can be deposited by a known method such as a sputtering method or a vacuum deposition method.

The dielectric layers 26 and 28 play a role of insulating the light emitting layer 27, and a material having a high dielectric constant such as SiNx is selected so that a high electric field can be applied to the light emitting layer 27. Various materials can be used for the light emitting layer 27. For example, when ZnS: Mn is used, the emission color can be yellow-orange, and when ZnS: Tb, F is used, green emission can be obtained. The drive electrode 29 is formed of an opaque electrode material such as Al and Cr as described above. Further, the transparent electrodes 25 and the drive electrodes 29 are matrix-wired, and therefore, the intersecting portions of the transparent electrodes 25 and the drive electrodes 29 are light emitting elements. The other layers are formed on the entire surface.

On the other hand, the lower electrode 21, the photoelectric conversion layer 22, and the transparent electrode 23 are sequentially laminated on the substrate 20, and the image reading section 5 is constituted by this. The lower electrode 21 and the transparent electrode 23 are matrix-wired, so that the intersecting portion of the lower electrode 21 and the transparent electrode 23 serves as a light receiving element. The photoelectric conversion layer 22 is formed on the entire surface. The transparent electrode 23 and the photoelectric conversion layer 22 may be formed on the entire surface, and only the lower electrode 21 may be formed in a stripe shape. Further, the photoelectric conversion layer may be formed separately for each element. The photoelectric conversion layer 22 uses a-Si.
By depositing a-Si by the CVD method, it is possible to easily deposit the film over a large area and uniformly.

Between the display unit 1 and the image reading unit 5,
A transparent spherical spacer 30 is arranged to insulate the two and keep the distance therebetween constant. That is, spherical spacers 30 having the same size are dispersed on one of the substrates, a transparent adhesive 31 is dispersed thereon, and then a light receiving element is arranged between the light shielding film formed by the drive electrode 29. Positioning is performed as described above, and uniform pressure is applied to bond the both. It is desirable that the adhesive used here has a refractive index substantially the same as that of the spherical spacer 30. This is because this makes it possible to prevent light that has entered between the light-shielding films from being diffusely reflected between the two substrates. Note that a transparent substrate having a uniform thickness may be used instead of the spherical spacer 30. In that case, it goes without saying that a transparent substrate having a refractive index substantially the same as that of the adhesive is used.

Generally, the resolution of the light receiving element largely depends on the distance between the substrates, but with the above configuration, the distance between the substrates can be arbitrarily and easily changed by the spherical spacer 30 and easily optimized. Can be measured. Further, by forming the display unit 1 and the image reading unit 5 on separate substrates, the individual yields can be improved.

Further, in FIG. 8, the lower electrode 33, the photoelectric conversion layer 34, and the transparent electrode 35 are sequentially laminated on the substrate 32 to form an image reading portion. The lower electrode 33 is formed in a stripe shape and is matrix-connected with the transparent electrode 35. Therefore, the transparent electrode 35 may be formed on the entire surface, or may be formed in a stripe shape in the direction orthogonal to the lower electrode 33. Further, the photoelectric conversion layer 34 can be formed by depositing a-Si by the CVD method as described above, but it may be formed on the entire surface or separately for each pixel.

After the image reading section is constructed as described above, an insulating layer 36 for insulating the image reading section and the display section is formed on the transparent electrode 35, and the insulating layer 36 also serves as a light shielding layer. The drive electrode 37, the dielectric layer 38, the light emitting layer 39, the dielectric layer 40, and the transparent electrode 41 are sequentially laminated to form a display unit. The material used for each layer is the same as that described in FIG. 7. The drive electrodes 37 are formed in a stripe shape and are matrix-connected with the transparent electrodes 41. Therefore, the transparent electrode 41 may be formed on the entire surface, or may be formed in a stripe shape in the direction orthogonal to the drive electrode 37. The light emitting layer 39 may be formed on the entire surface or may be formed separately for each pixel.

Finally, the protective layer 4 is formed on the transparent electrode 41.
Form 2. As the protective layer 42, a transparent inorganic material such as glass, a transparent organic material such as an inorganic compound or a resin is used. The light receiving element composed of the lower electrode 33 and the transparent electrode 35 is naturally arranged between the light emitting element composed of the drive electrode 37 and the transparent electrode 41.

By the way, when reading an image,
It is known that the shorter the distance between the original and the light receiving element, the more accurately the image can be read. Therefore, the transparent substrate 2 of FIG.
It is desirable that the protective layer 42 of FIGS. 4 and 8 be as thin as possible. Therefore, as the transparent substrate 24 in FIG. 7, a transparent sheet-shaped resin can be used instead of glass. For example, if PES (polyether sulfone) made by Sumitomo Bakelite is used, the film thickness can be freely set from 50 μm to 200 μm, and the glass transition temperature is 223 ° C., so that it can withstand relatively high temperature processes. Moreover, since it has good acid resistance and alkali resistance, it is not deformed or dissolved by an etching solution or a developing solution when patterning the electrodes and the dielectric layer. In fact
When SiNx is used as the dielectric layers 26 and 28 in FIG. 7, SiNx is usually deposited by a plasma CVD method, and the substrate temperature is about 200 ° C. during this process. If a heat resistant resin is used, the dielectric layers 26 and 28 can be deposited without deformation. The light emitting layer 27 is usually deposited by EB vapor deposition, and the temperature of the substrate is about 150 to 200 ° C at this time, but it is clear that the heat-resistant resin such as PES can be used for good deposition. is there.

The same applies to the case shown in FIG. 8, and the above-mentioned PES can be used as the protective layer 42. However, in this structure, the protective layer 42 is formed at the end, and therefore the structure shown in FIG. Unlike the case of using the structure shown in FIG. 7, since heat resistance and the like are not required, any transparent resin can be used. If it is in the form of a sheet, it may be attached to the transparent electrode 41 with a transparent adhesive, and if it is a liquid such as polyimide, it may be deposited by a method such as a spin coater method, a roll coater method or a dip method. Good. As described above, the protective layer can be formed with good yield by forming the surface serving as the document mounting surface with the resin.

Next, the connection between the display section and the image reading section and the respective drive circuits will be described. FIG. 9 is a plan view showing a schematic configuration of an image reading / display device in which the light emitting element 3 is 3 × 3 pixels and the light receiving element 7 is 2 × 3.
The substrate 2 and the substrate 6 of the image reading unit 5 are arranged so as to be offset from each other in the vertical and horizontal directions by a predetermined amount, and the peripheries of the overlapping substrates are adhesively fixed by an adhesive 47. As the adhesive 47, an epoxy-based or silicon-based adhesive is used. Then, a light emitting element drive circuit 45 composed of an IC and other circuit elements is mounted on the shifted two sides of the substrate 2 of the display unit 1, and the light emitting element 3 is mounted on the light emitting element 3 by an appropriate technique such as a printed circuit (not shown). It is connected. Similarly, a light receiving element drive circuit 46 composed of an IC and other circuit elements is mounted on the two shifted sides of the substrate 6 of the image reading section 5, and is connected to the light receiving element 7 by a printed circuit or the like. ..

FIG. 10 is a sectional view of a portion indicated by AA 'in FIG. 9, in which the display substrate 2 and the image reading substrate 6 are kept at a predetermined interval by a spacer 49, and the surroundings block air. As shown in FIG. The height of the spacer 49 is adjusted based on the thickness of the display substrate 2 and the size of the light incident window 48 so that the MTF of the optical characteristic becomes large. For example, the element density is 8 dots / mm, that is, the element pitch is 125 μm, the thickness of the display substrate 2 is 50 μm,
When the size of the light incident window 48 is 40 μm, the spacer 4
The height of 9 is about 50 μm, which is substantially the same as the thickness of the display substrate 2. In this way, the gap between the two substrates 2 and 6 is quite narrow, and it is impossible to arrange a driving IC or the like between them, and moreover, if the height of the spacer 49 is increased, the MTF becomes smaller, so that a driving IC can be mounted. It is not possible to widen the gap between the two substrates. Therefore, as shown in FIGS. 9 and 10, the light emitting element drive circuit 45 and the light receiving element drive circuit 46 are mounted on the non-overlapping substrate portion of the two shifted substrates. It should be noted that the drive circuits 45 and 46 are mounted on each board by TAB (Tape A
It may be performed by utomatic bonding) or COG (Chip On Glass).

FIG. 11 shows the light emitting element 3 and the light emitting element drive circuit 4.
5 is a diagram showing an equivalent circuit of the connection of FIG. 5, in which a light emitting element drive circuit 45 is composed of a row driver 50 and a column driver 51, which are connected to respective wirings in rows and columns. FIG. 12 is a diagram showing an equivalent circuit of the connection between the light receiving element 7 and the light receiving element drive circuit 46. The light receiving element drive circuit 46 includes a shift register 52, an analog switch 53, and a current / voltage converter 54. The register 52 is connected to the column wiring and the analog switch 53 is connected to the row wiring.

The above is the case where the display unit 1 and the image reading unit 5 are formed on different substrates, but as shown in FIG. 8, the image reading unit 5 and the display unit 1 are formed by laminating on one substrate. In this case, since there is only one substrate, as shown in FIG.
The display element drive circuit 56 and the light receiving element drive circuit 57 are arranged on two sides of the substrate 55. Although not shown in FIG.
3, the display element drive circuit 56 is connected to the light emitting element by a printed circuit or the like.
Naturally, 7 is connected to the light receiving element.

The first embodiment of the present invention has been described above. Next, the second embodiment of the present invention will be described.
In the first embodiment, the light receiving element is arranged between the light emitting element and the light emitting element, but in the second embodiment, the light emitting element is provided with an opening, and the light receiving element is provided at the position of the opening. Are arranged, and the rest is the same as in the first embodiment.

FIG. 14 is a perspective view showing the configuration of the second embodiment, and FIG. 15 is a sectional view thereof. Light emitting elements 61 are formed separately on a substrate 60 and are arranged two-dimensionally. A display unit is configured. An opening 62 is provided at the center of each light emitting element 61, and a light shielding film 65 is provided at a portion other than the opening 62 so as to prevent extra light from entering from other than the original surface as shown in FIG. Has been formed.
Further, a light receiving element 64 is separately formed on the substrate 63 for each element, and is arranged two-dimensionally to form an image reading unit. The substrate 60 and the substrate 63 are the same as the light receiving element 6
4 is positioned so as to be located immediately below the opening 62 of the light emitting element 61, and is bonded by an adhesive. In FIG. 15, 66 indicates a spacer.

In this structure, the display surface naturally serves as the document mounting surface. Therefore, as shown by the arrow in FIG. 15, the light emitted from the light emitting element 61 and reflected by the document surface passes through the opening 62. Since the incident light is incident on the light receiving element 64, the reflected light from the document surface can be efficiently incident on the light receiving element 64.

14 and 15, the light emitting element 61 is shown.
Although one opening 62 is provided in the above, a plurality of openings may be provided. FIG. 16 is a diagram showing a configuration example thereof. In FIG. 16, one light emitting element 67 is provided.
Are provided with four openings 68, and a light receiving element 69 is arranged for each opening 68. This configuration is meaningful. Generally, a resolution of about 400 SPI is required for image reading, whereas a resolution of about 200 SPI is sufficient for display. Therefore, for example, a light receiving element is formed so as to obtain a resolution of 400 SPI. The light emitting element is half that 200 SPI
If it is formed so as to obtain the above resolution, it is possible to form one that can satisfy both the resolution of image display and the resolution of image reading. Moreover, if both are to be formed so as to obtain a resolution of 400 SPI, a great load will be applied to the mounting of the light emitting element, the light receiving element and their drive circuits, but the configuration shown in FIG. 16 is adopted. In this case, it can be manufactured with high yield. In FIGS. 14 and 16, the display unit and the image reading unit are formed on separate substrates and bonded together. However, as shown in FIG. 8, the image reading unit and the display unit are provided on one substrate. As a matter of course, they can be formed by stacking.

Next, a third embodiment of the present invention will be described. In the above-described first and second embodiments, the document placing surface at the time of image reading is supposed to coincide with the display surface, but in the third embodiment, the display surface and the document placing surface are different. The rest is the same as in the first embodiment. An example of the configuration is shown in FIG.

FIG. 17 is a sectional view showing the schematic arrangement of the third embodiment of the image reading / display apparatus according to the present invention.
On the transparent substrate 70, a plurality of light receiving elements 71 having a light shielding film 72 formed thereon are two-dimensionally formed at predetermined intervals to form a display portion, and on the transparent substrate 73, a plurality of light emitting elements are formed. The image reading unit 5 is formed by two-dimensionally forming the elements 74 at predetermined intervals. Then, the display section and the image reading section are aligned and fixed so that the light receiving element 71 is positioned between the light emitting elements.

Here, as will be apparent from what will be described later, the light emitting element 74 needs to emit light on both sides of the transparent substrate 73 side and the image reading section side. Therefore, in FIG.
As shown in FIG. 8, the transparent electrode 75, the first insulating layer 76, the light emitting layer 77, the second insulating layer 78, and the transparent electrode 79 are laminated in this order. The light receiving element 71 is a photodiode formed of a-Si or CdS,
A photoelectric conversion element such as CdSe can be used. At that time, the light shielding film 72 can also be used by forming the drive electrode on the display unit side with an opaque metal such as Al or Cr.

In this structure, the image reading /
When the display device is used as an image display device, each light emitting element 74 is caused to emit light by a simple matrix system or an active matrix system by a display drive circuit (not shown in FIG. 17). Therefore, in FIG. 17, the transparent substrate 7
The display image can be observed from the 3 side. When used as an image reading device, as shown in FIG. 19, a document 80 is placed on a transparent substrate 70, a light receiving element 71 is driven by an image reading drive circuit (not shown), and a display is performed. The drive circuit causes the light emitting element 74 adjacent to the light receiving element 71 to simultaneously emit light with the same brightness. As a result, the light emitted from the light emitting element 74 is reflected by the original 80 and enters the light receiving element 71, as shown by the arrow in FIG. At this time, it is clear that the light shielding film 72 can prevent the light emitted from the light emitting element 74 from directly entering the light receiving element 71.

The image reading / displaying device shown in this embodiment can be constructed by forming the display portion and the image reading portion on separate substrates and bonding them together as shown in FIG. It is also possible to stack the display section and the image reading section on one substrate as shown in FIG.

In FIG. 20, the display portion is a transparent substrate 81.
A transparent electrode 82, a dielectric layer 83, a light emitting layer 84, a dielectric layer 85, and a transparent electrode 86 are sequentially stacked on top of this. The materials used for the dielectric layers 83 and 85 and the light emitting layer 84 are the same as those described in the first embodiment. Also, the point that the transparent electrodes 82 and the transparent electrodes 85 are arranged in a matrix is the same as in the first embodiment, and therefore, the intersecting portions of the transparent electrodes 82 and the transparent electrodes 85 are the light emitting elements.

On the other hand, the transparent electrode 90 is formed on the transparent substrate 90.
1, a photoelectric conversion layer 92, and a drive electrode 93 which also serves as a light-shielding film are sequentially stacked to form an image reading unit. The transparent electrodes 91 and the drive electrodes 93 are matrix-wired, so that the intersecting portions of the transparent electrodes 91 and the drive electrodes 93 serve as light receiving elements. The drive electrode 9
3 is formed of an opaque metal material such as Al and Cr. A transparent spacer 8 is provided between the display unit and the image reading unit in order to insulate the two units and to keep the distance therebetween constant.
7 is arranged, and both substrates are joined by a transparent adhesive arranged in the space indicated by 94 in FIG. Further, in FIG. 21, first, a transparent electrode 101, a dielectric layer 102, a light emitting layer 103, a dielectric layer 104, and a transparent electrode 105 are sequentially laminated on a transparent substrate 100 to form a display portion. Naturally, the transparent electrodes 101 and the transparent electrodes 105 are matrix-wired. The light emitting layer 103 may be formed on the entire surface or may be formed separately for each pixel.

After the display section is constructed as described above, an insulating layer 106 for insulating the display section and the image reading section from each other is formed on the transparent electrode 105, and a driving layer which also serves as a light shielding layer is formed thereon. Electrode 107, photoelectric conversion layer 108, transparent electrode 10
9 is sequentially laminated to form an image reading unit. here,
The material used for each layer is the same as that described in the first embodiment, the drive electrode 107 and the transparent electrode 109 are matrix-wired, and even if the photoelectric conversion layer 108 is deposited on the entire surface, The same applies to the case where each pixel may be formed separately. Then, finally, the protective layer 110 is formed on the transparent electrode 109. The light receiving elements are naturally arranged between the light emitting elements.

Next, a description will be given of an embodiment relating to the connection between the light emitting element and the light receiving element formed on separate substrates and the connection between these elements and other circuits such as a drive circuit thereof. Regarding the connection between the light emitting element and its drive circuit and the connection between the light receiving element and its drive circuit when the light emitting element and the light receiving element are formed on separate substrates, examples have been given in FIGS. 9 and 10 above. Here, an embodiment different from that will be described.

As shown in FIGS. 7, 15 and 17, the light emitting element and the light receiving element are formed on separate substrates, and these two substrates are arranged so that the light emitting element and the light receiving element face each other. In view of the resolution of image reading, it is desirable that the distance (T ₀ ) between the light emitting element and the document and the distance (T ₁ ) between the light emitting element and the light receiving element have the same value. Simulation results have shown that a smaller value is desirable. In the case of such a configuration, the value is determined by the thickness of the substrate on which the light emitting element is formed (hereinafter referred to as the light emitting element substrate). In practice, the thickness of the light emitting element substrate is limited to 50 to 100 μm, so the distance between the light emitting element and the light receiving element must be fixed integrally by forming a gap corresponding to the thickness of the light emitting element substrate. I won't.

By the way, as a method of connecting the electrode terminals having a gap, the method described in Japanese Patent Application Laid-Open No. 1-227458 is known. This is to perform only the first bonding using a metal wire, and to form the bump on the convex by cutting the wire with a laser beam without performing the second bonding, but according to this method, the height of the bump is Since it is at most about 50 μm, it cannot be applied to the mounting of the image reading / displaying device of the present invention.

Therefore, in the image reading / display apparatus of the present invention, a flexible printed circuit board (hereinafter, referred to as F
(Referred to as PC) is interposed between the light emitting element substrate and the light receiving element substrate to connect the light emitting element and the light receiving element to their drive circuits, and the FPC has a thickness of 50 to 100 μm.
The fact that m is used makes T ₀ and T ₁ substantially equal.

FIG. 22 is a sectional view showing the structure of one embodiment of the present invention. A light receiving element substrate 122 on which a light receiving element 121 is formed is shown.
And the light emitting element substrate 124 on which the light emitting element 123 is formed are arranged to face each other so that the respective elements are on the inner side and the positions of the respective elements correspond to each other. As shown in FIG. 14, the light emitting element 123 is formed with an incident window 126 for allowing the reflected light from the original 125 to enter the light receiving element 121, and the light emitting element 123 has a light receiving element 121 side. The light shielding layer 127 is provided so that the light emitted from the light emitting element 123 does not directly enter the light receiving element 121.

The FPCs 130 and 131 are interposed between the light receiving element substrate 121 and the light emitting element substrate 124, and the electrode 128 extracted from the light receiving element 121 is
It is connected to the pattern of the Ni-Au plated layer 136 formed on the copper foil 134 of the FPC 130 and connected to an external light receiving element drive circuit or the like. Similarly, the electrode 129 led out from the light emitting element 123 is connected to the pattern of the Ni-Au plating layer 135 formed on the copper foil 132 of the FPC 131 and is connected to an external light emitting element driving circuit or the like.
Note that in FIG. 22, 137, 138, 139, and 14
Reference numeral 0 represents a polyimide layer, and 133 represents a spacer. The spacer 133 may be provided if necessary.

Here, as the light emitting element 12, EL (Elec
tro Luminescence) element, and a glass substrate having a thickness of 100 μm was used as the light emitting element substrate 124. The EL element includes an ITO layer that is a transparent electrode and a SiN layer that is a first insulating layer.
x layer, ZnS: Mn that is the light emitting layer, S that is the second insulating layer
iNx and Al electrode layer 5 which also functions as a light shielding layer for the upper electrode
It has a layered structure. ZnS: Mn is used for the light emitting layer because high brightness can be stably obtained and it is suitable as a light source and a display element. The respective film thicknesses of the ITO layer are 140 nm, the SiNx layer is 300 nm,
The light emitting layer has a thickness of 500 nm, and the Al electrode layer has a thickness of 1 μm.

An entrance window made of an Al electrode is formed in the center of the EL element, and the other part is shielded from light. As a result, the light emitted from the light emitting layer does not enter the direct light receiving element 121, but irradiates the original once, and the reflected light passes through the incident window and reaches the light receiving element 121.

The ITO electrode and the Al electrode have a matrix structure. In FIG. 22, the ITO electrode is led out to the right side and connected to the FPC 131 at its end. Further, the Al electrode is drawn out in a direction orthogonal to the ITO electrode, and the FPC131 or another FP is terminated at the end thereof.
Connected to C.

In FIG. 22, the two-layer FPC 131 manufactured by Nippon Mektron Co., Ltd. is used, but a single-layer FPC can also be used. A single layer FPC is shown in FIG.
As shown in FIG. 3, the copper foil 141 has polyimide layers 142, 1
It has a structure sandwiched by 43, and a Ni—Au plated layer 145 is formed in a thickness of 2 to 3 μm in a portion connected to an external terminal. Polyimide layer 14
The film thicknesses of 2 and 143 are each about 35 μm, and the film thickness of the copper foil 141 is about 18 μm.

In the FPC, the thickness of the polyimide layer and the copper foil may be several μ regardless of whether it is a single layer or two layers.
Since the total thickness can be arbitrarily set in the range of 50 to 150 μm by adjusting about m, the total thickness is 100 μm according to the film thickness of the light emitting element substrate 124 by using the two-layer FPC in this embodiment.
And The breakdown is that the polyimide layer 140 is 34 μm, the intermediate copper foil layer is 34 μm, and the first copper foil layer and the second copper foil layer are both
15 μm, and the Ni-Au plating layer 135 is 2 μm.

Ni-Au plating layer 135 of FPC 131
Terminal pattern and the ITO electrode 12 of the light emitting element substrate 124
The connection with 9 is performed by interposing a conductive sheet between them, aligning the patterns of both, and then thermocompression-bonding and fixing. Alternatively, a conductive adhesive may be used to bond the two. Al electrode and FPC
Connection with is done in the same way. As described above, the ITO electrode and the Al electrode of the light emitting element 123 are connected to the external circuit by the FPC.

A photodiode made of a-Si is used as the light receiving element 121. The film thickness is about 500 nm. a
-Si is suitable for the present invention because a uniform film can be easily deposited on a large area by the plasma CVD method or the like.
In addition to this, a photoconductor represented by CdSe may be used.

In the light-receiving element 121, extraction electrodes and common electrodes are wired in a matrix, and the common electrodes are extracted to the left side shown in FIG. 22 and are connected to the FPC 130 at their ends. In addition, the extraction electrode is connected to the FPC in a direction perpendicular to the common electrode (not shown) and on the side where the Al electrode of the light emitting element 121 is not extracted. The method of connecting the FPC and these electrodes is the same as in the case of the light emitting element substrate 124.

Spacer 133 for shaping the gap
The particle size is the same as the thickness of the light emitting element substrate 124.
Transparent particles having a size of μm and composed of a cross-linked copolymer were used. Although not shown in FIG. 22, a transparent adhesive material is filled in the gap portion other than the FPC together with the spacer 133. Then, alignment is performed so that the light receiving element 121 and the light emitting element 123 are correctly opposed to each other, and the light receiving element substrate 122
The light emitting element substrates 124 are evenly weighted and bonded to each other so that both substrates are fixed. This constitutes the image reading / display device shown in FIG.

According to this structure, a highly reliable connection can be made by a simple process, and therefore, it is suitable for mounting a display element such as an EL light emitting element, in which several mA flows per element at a high driving voltage. Moreover, by utilizing the thickness of the FPC itself, a gap between the substrates can be formed at the same time, and by interposing particles for forming the gap, a structure with a small gap variation similar to that of a liquid crystal cell can be obtained.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above embodiments and various modifications can be made. For example, a color image sensor / color display is possible by making the light emitting element multicolored. That is, in the case of an EL element, red (R), green (G), and blue (B) color light can be emitted by changing the light emitting material, and since the materials are all transparent,
With the laminated structure, a color display can be easily constructed, and by using it as a light source, a color image sensor can be realized.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a schematic configuration of a first embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a structure of a light emitting element.

FIG. 3 is a diagram for explaining the arrangement of a light emitting element and a light receiving element.

FIG. 4 is a diagram for explaining a mode in which the one shown in FIG. 1 is used as an image reading device.

FIG. 5 is a diagram for explaining another method of image input.

FIG. 6 is a diagram for explaining an optimum position of a light receiving element.

FIG. 7 is a cross-sectional view showing a structure in the case where a display section and an image reading section are formed on different substrates.

FIG. 8 is a cross-sectional view showing a structure in the case where a display unit and an image reading unit are stacked and formed on one substrate.

FIG. 9 is a diagram for explaining the connection of the light emitting element drive circuit and the light receiving element drive circuit when the display section and the image reading section are formed on different substrates.

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

FIG. 11 is a diagram showing an equivalent circuit of a connection between a light emitting element and a light emitting element driving circuit.

FIG. 12 is a diagram showing an equivalent circuit of a connection between a light receiving element and a light receiving element drive circuit.

FIG. 13 is a diagram for explaining the connection of the light emitting element drive circuit and the light receiving element drive circuit when the display unit and the image reading unit are stacked and formed on one substrate.

FIG. 14 is a perspective view showing a configuration of a second exemplary embodiment of the present invention.

15 is a cross-sectional view of the configuration shown in FIG.

FIG. 16 is a perspective view showing a modification of the second embodiment.

FIG. 17 is a sectional view showing the configuration of the third exemplary embodiment of the present invention.

FIG. 18 is a cross-sectional view showing a structure of a light emitting element.

FIG. 19 is a diagram for explaining a mode in which the one shown in FIG. 17 is used as an image reading device.

FIG. 20 is a cross-sectional view showing the structure when the display unit and the image reading unit are formed on different substrates.

FIG. 21 is a cross-sectional view showing a structure in the case where a display unit and an image reading unit are formed by being stacked on one substrate.

FIG. 22 is a cross-sectional view showing a configuration of an example of mounting when the light emitting element substrate and the light receiving element substrate are arranged to face each other.

FIG. 23 is a sectional view showing the structure of a single-layer FPC.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Display part, 2 ... Transparent substrate, 3 ... Light emitting element, 4 ... Light-shielding film, 5 ... Image reading part, 6 ... Substrate, 7 ... Light receiving element.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location H01L 27/14 H04N 5/335 Z

Claims (17)

[Claims] 1. An image reading / display apparatus in which an image reading section in which light receiving elements are two-dimensionally arranged and a display section in which light emitting elements are two-dimensionally arranged are overlapped. The image reading unit side or the display unit side is a document placing surface, and the light receiving element is arranged at a position where light reflected from the document can be emitted from the light emitting element. Image reading / display device. 2. The image according to claim 1, wherein the original placement surface is the same surface as the display surface of the display unit, and a light shielding unit is formed on the image reading unit side of the light emitting element. Read / display device. 3. The image reading / displaying device according to claim 2, wherein the light shielding portion is formed of an electrode for driving a light emitting element. 4. The document placing surface is formed on the side of the image reading portion opposite to the display surface of the display portion, and the light shielding element is formed on the display portion side of the light receiving element. The image reading / display device described. 5. The image reading / displaying device according to claim 4, wherein the light shielding portion is formed of an electrode for forming a light receiving element. 6. The image reading / displaying device according to claim 1, wherein the image reading unit is located within an area of the display unit. 7. The image reading / display apparatus according to claim 1, wherein the light receiving element is arranged between the light emitting element and the light emitting element. 8. The image reading / displaying according to claim 7, wherein each light receiving element is arranged at a position where light from a pixel area adjacent to a pixel area corresponding to each light receiving element does not directly enter. apparatus. 9. The image reading / display apparatus according to claim 7, wherein at least the light emitting element adjacent to each light receiving element is made to emit light at the same time when the image is read. 10. The image reading / reading device according to claim 1, wherein at least one light transmitting opening is formed in the light emitting element, and the light receiving element is disposed above or below the light transmitting opening. Display device. 11. The image reading / displaying apparatus according to claim 1, wherein the display section and the image reading section are formed on separate substrates and are formed by bonding them together. 12. The display section substrate and the image reading section substrate are arranged so as to be displaced from each other in the vertical direction and the horizontal direction by a predetermined amount, and the drive circuit of the display section and the drive circuit of the image reading section. 12. The image reading / display apparatus according to claim 11, wherein each of the display unit substrate and the image reading unit substrate is mounted on two non-overlapping sides. 13. The image reading / display apparatus according to claim 1, wherein the display unit and the image reading unit are laminated on one substrate. 14. The image reading / displaying device according to claim 1, wherein the document placing surface is made of resin. 15. An image reading / display apparatus in which a light receiving element substrate having a light receiving element and a light emitting element substrate having a light emitting element are arranged so that the light receiving element and the light emitting element face each other. An image reading / displaying device, wherein a flexible printed circuit board having a drive electrode of the light emitting element and / or a drive electrode of the light receiving element is interposed between the light emitting element substrate and the light emitting element substrate. 16. The image reading / measuring device according to claim 15, wherein the flexible printed circuit board is disposed at an end of at least two sides of the four sides of the light emitting element substrate and the light receiving element substrate. Display device. 17. The image reading / displaying device according to claim 15, wherein a transparent spacer is interposed between the light emitting element substrate and the light receiving element substrate which are arranged to face each other.