JP4539312B2 - Electro-optical device and electronic apparatus - Google Patents

Description

The present invention relates to an electro-optical device and an electronic apparatus. In particular, the present invention relates to an electro-optical device that can transmit a high-frequency signal accurately and stably at high speed to a drive circuit, and an electronic apparatus including such an electro-optical device.

In recent years, liquid crystal display devices have been widely used as image display devices. Such a liquid crystal display device generally includes an image display unit obtained by enclosing a liquid crystal material between a pair of glass substrates and bonding the periphery together with a sealant, and a signal for causing the image display unit to display an image. And interface means including a circuit board for connecting the driving circuit and an external device, and a connection portion.
Conventionally, as the interface means, a connection method in which a flexible wiring board (FPC) is connected by an anisotropic conductive film (ACF) is mainly used. However, with the recent progress of high image quality and serialization of transmission signals, it is necessary to increase the transmission speed between the external device and the driving circuit.
However, in the conventional method of connecting FPC boards by ACF, when a high frequency signal of several hundred MHz to several GHz is transmitted, the influence of noise due to electromagnetic radiation becomes obvious and it is difficult to perform normal signal processing. There was a problem.

Therefore, although it is not an interface means between the driving circuit and the external device, as a countermeasure against noise in the image display device, a method using a microstrip line is proposed for repair wiring in the circuit board of the liquid crystal display device. Yes. (For example, see Patent Document 1)
More specifically, as shown in FIG. 16, in the repair wiring 502, at least one of a surface direction distance H from the end of the ground plane, a vertical direction distance D from the ground plane, a width W, and a thickness h is set. A liquid crystal display device is disclosed in which the electromagnetic wave radiation of the repair wiring as a microstrip line is optimized by adjusting.
JP 2001-249355 A (Claims, FIG. 1)

However, Patent Document 1 uses a microstrip line as a repair wiring for repairing an electrical wiring formed in a circuit board of a liquid crystal display device, and it is necessary to lengthen the microstrip line.
That is, with the increase in the screen size of the liquid crystal display device, the electrical wiring becomes longer, which necessitates a longer microstrip line as the repair wiring, and at the same time, causes new problems of increased wiring capacity and electromagnetic interference. .
Although a method for optimizing the relationship between the wiring capacity of the microstrip line and the electromagnetic radiation has been proposed, it corresponds to the large screen of a liquid crystal display device. There was a problem that it could not be applied as it was.
Further, the repair wiring is substantially a single function and does not use a microstrip line as a shielded line and a normal wiring as a non-shielded line. Therefore, it has not been possible to provide an electro-optical device that can accurately and stably transmit a high-frequency signal to a driving circuit, not only a normal low-frequency signal but also a high-frequency signal.

Accordingly, the inventors of the present invention have made extensive studies on the above problems, and as a result, transmitted to the interface means between the external device and the drive circuit with a shielded wire or a shielded wire corresponding to the influence of electromagnetic radiation. By applying the line, not only the normal low frequency signal but also the high frequency signal can be accurately and stably transmitted at high speed to the driving circuit, and power saving can be achieved. It has been found that the wiring design becomes easy.
That is, according to the present invention, a high-frequency signal can be accurately and stably transmitted at high speed by providing a shield line or a transmission line corresponding to the shield line in a part of the interface means for inputting a signal to the driving circuit. As a result, it is an object of the present invention to provide an electro-optical device excellent in improving image characteristics and power saving, and an electronic apparatus including such an electro-optical device.

According to the present invention, in an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside, the interface An electro-optical device including a shield line for transmitting a high-frequency signal is provided as part of the means, and the above-described problems can be solved.
That is, by configuring the electro-optical device in this way, using shielded wires that suppress the influence of electromagnetic radiation, the drive circuit is accurate not only for normal low-frequency signals but also for high-frequency signals. Good and stable high-speed transmission. Accordingly, with the high-speed transmission of high-frequency signals, it is possible to contribute to improvement of image characteristics and power saving of the electro-optical device.

In configuring the electro-optical device of the present invention, it is preferable that the shield line includes at least one of a microstrip line, a coplanar line, and a coaxial line.
That is, by using such a general-purpose shield wire, wiring design can be easily performed at low cost.

In configuring the electro-optical device of the present invention, it is preferable that a plurality of shield wires are provided and their impedances are equal.
In other words, impedance matching can minimize transmission loss of a high-frequency signal caused by impedance mismatch, and can transmit a high-frequency signal to a driving circuit at a higher speed and more stably. .

In configuring the electro-optical device of the present invention, as a main element of the interface means,
It is preferable that a flexible substrate is provided and a shield wire is provided on the surface thereof.
That is, by adopting such a configuration of the electro-optical device, the shape of the interface means can be easily adapted to the usage state.

In constructing the electro-optical device of the present invention, it is preferable that a non-shielded wire is arranged in a predetermined region together with the shielded wire.
By adopting such a configuration, for example, a shielded wire is used for a high-frequency signal that is greatly affected by electromagnetic radiation, while an unshielded wire is used for a low-frequency signal that is less affected by electromagnetic radiation. Can do. In other words, shielded lines are used for signals that require high-speed communication, such as image display system signals, and unshielded lines for signals that do not pose a problem even in low-speed communication, such as power system signals and setting system signals. It is possible to use properly, such as using. As a result, the applied voltage for driving can be minimized and power consumption can be reduced.

In configuring the electro-optical device of the present invention, it is preferable that shielded wires and non-shielded wires are alternately arranged in the planar direction.
By adopting such a configuration, it becomes possible to minimize the influence of electromagnetic radiation, and high-frequency signals can be transmitted with high accuracy and stability at high speed. Moreover, since the space | interval of an adjacent shield wire can be expanded, the more excellent shielding effect can be acquired.

In configuring the electro-optical device of the present invention, it is preferable that shielded wires and non-shielded wires are arranged in multiple layers in the vertical direction.
With this configuration, the layout design of the shielded wire and the non-shielded wire is facilitated, and electrical connection with an external device is facilitated. Moreover, since the space | interval of an adjacent shield wire can be expanded, the more excellent shielding effect can be acquired.

In configuring the electro-optical device of the present invention, it is preferable that a coaxial line connector is formed on a part of the flexible substrate.
By setting it as such a structure, the connection position of a coaxial line and an external device can be suitably selected according to a use.

In configuring the electro-optical device of the present invention, it is preferable that a temperature compensation circuit is provided on the flexible substrate or the driving circuit.
With such a configuration, a high-frequency signal can be accurately and stably transmitted at high speed even when the ambient temperature changes.

In configuring the electro-optical device of the present invention, it is preferable that a ground of the shield wire is formed in a part of the interface means.
With such a configuration, the shielding effect of the shield wire can be effectively exhibited without providing a special ground on the substrate.

In configuring the electro-optical device of the present invention, it is preferable to set the communication speed for transmitting a signal via a shielded wire to a value of 180 Mbps or more.
With such a configuration, not only predetermined high-speed communication is possible, but also the drive applied voltage can be suppressed and the power consumption of the electro-optical device can be reduced.

In configuring the electro-optical device of the present invention, it is preferable that a part of the interface means includes a UTP (Unshielded Twist Pair) line as a transmission line for transmitting a high-frequency signal.
By adopting such a configuration, a high-frequency signal can be accurately and stably transmitted at high speed with respect to the driving circuit as well as a normal low-frequency signal.
Accordingly, with the high-speed transmission of high-frequency signals, it is possible to contribute to improvement of image characteristics and power saving of the electro-optical device.
Further, since it is not necessary to provide a special ground wiring on the substrate, the wiring design can be easily performed.

Another aspect of the present invention is an electronic apparatus including any one of the above-described electro-optical devices.
That is, by providing a shield line for transmitting a high-frequency signal or a transmission line corresponding to the shield line in a part of the interface means for inputting a signal to the drive circuit, the drive circuit can be electrically connected. It is possible to contribute to improvement of image characteristics and power reduction in the optical device, and it is possible to improve the adaptability of an electronic apparatus including such an electro-optical device.

Hereinafter, embodiments of the electro-optical device of the present invention and an electronic apparatus including such an electro-optical device will be described in detail with reference to the drawings. However, this embodiment shows one aspect of the present invention and does not limit the present invention, and can be arbitrarily limited within the scope of the present invention.

[First Embodiment]
The first embodiment is an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside. A part of the interface means includes a shield line for transmitting a high-frequency signal or a transmission line corresponding to the shield line.
Hereinafter, the electro-optical device according to the first embodiment of the present invention will be described taking the liquid crystal display device 100 including the predetermined interface unit 4 as an example with reference to FIGS. 1 to 15 as appropriate.

1. First, the basic structure of the liquid crystal display device 100 according to the first embodiment of the present invention will be described in detail with reference to FIG. Here, FIG. 1 is a schematic view of a liquid crystal display device 100 according to the present embodiment.
The liquid crystal display device 100 includes a liquid crystal panel 220 for displaying an image.
The liquid crystal panel 220 mainly includes a pixel substrate 14 described later, a color filter substrate 12,
The liquid crystal material 232 and the liquid crystal material 232 can be electrically controlled to display images such as characters and figures.
The side surface of the liquid crystal display device 100 is provided with a substrate overhanging portion 14T that projects outward from the outer shape. On the substrate overhanging portion 14T, an output side electric wiring 65, an input side electric wiring 67, and a semiconductor element 91 including a driving circuit are mainly formed.

The interface means 4 is a member for inputting a signal from the outside to the semiconductor element 91 including the driving circuit, and includes a flexible substrate 93 as a main element. On the surface of the flexible substrate 93, a shielded wire or a transmission line 50 corresponding to the shielded wire and a non-shielded wire 51 are wired.
Further, the end portion of the flexible substrate 93 and the end portion of the overhanging portion 14T are in contact with each other so as to overlap each other and form the connection portion 8. In the connection portion 8, although not shown, the electrical wiring 67, the transmission line 50 corresponding to the shield line or the shield line, and the non-shield line 51 are, for example, via an anisotropic conductive film (ACF) or a bump. Electrically connected.
Therefore, as a high-speed signal to the driving circuit via the interface means 4,
When a driving signal or the like is input from the outside, the liquid crystal display device 100 can perform a predetermined image display accordingly.

2. Specific Structure of Liquid Crystal Display Device Next, with reference to FIGS. 2 to 3, a specific structure of the liquid crystal panel according to the first embodiment of the present invention,
That is, the cell structure, wiring, retardation plate and polarizing plate will be described. Note that FIG.
These are the schematic perspective views which show the liquid crystal panel 200 which comprises the liquid crystal display device which concerns on 1st Embodiment of this invention, FIG. 3: is a typical schematic sectional drawing of the liquid crystal panel 200. FIG.
The liquid crystal panel 200 shown in FIG. 2 is a liquid crystal panel 200 having a passive matrix structure, and an illuminating device such as a backlight or a front light, a case body, and the like (not shown) are appropriately attached as necessary. As a result, a liquid crystal display device is obtained.
In the present embodiment, a liquid crystal panel having an active matrix structure including a TFD element (Thin Film Diode) will be described as an example. However, a TFT element (Thin Film Tran
A liquid crystal panel having an active matrix structure using a non-linear element such as a sistor) or a liquid crystal panel having a passive matrix structure may be used.

(1) Cell Structure As shown in FIG. 2, a liquid crystal panel 200 is disposed opposite to a first substrate (color filter substrate) 12 having a glass plate, a synthetic resin plate or the like as a base 13, and similarly glass. A second substrate (element substrate) 14 having a base plate 27, a synthetic resin plate, or the like as a base 27 is bonded through a sealing material 230 such as an adhesive. The liquid crystal is injected into the space formed by the color filter substrate 12 and the element substrate 14 into the inner portion of the sealing material 230 through the injection port 230a, and then sealed with the sealing material 231. The cell structure is formed.
That is, as shown in FIG. 3, the liquid crystal 2 is interposed between the color filter substrate 12 and the element substrate 14.
32 is preferably filled and sealed.
In the following description, an example will be described in which the first glass substrate is used as the base of the first substrate, and the second glass substrate is used as the base of the second substrate.

(2) Wiring Also, as shown in FIG. 2, a plurality of striped data electrodes (second electrode pattern) are formed on the inner surface of the second glass substrate 27 (the surface facing the first glass substrate 13). 26,
A plurality of stripe-shaped scanning electrodes (first electrode patterns) 19 are preferably formed on the inner surface of the first glass substrate 13 (the surface facing the second glass substrate 27).
The data electrode 26 is preferably connected to the electrical wiring 29 outside the display area. Furthermore, it is preferable that the other scanning electrode 19 is electrically connected to the electric wiring 28 on the second glass substrate 27 through a sealing material 230 containing conductive particles.
Further, the intersecting regions of the data electrodes and the scanning electrodes are arranged in a matrix to form a large number of pixels, and the array of the large number of pixels constitutes the liquid crystal display region A as a whole.
In the following description, the second electrode pattern includes data electrodes and electrical wiring.

In addition, as shown in FIG. 2, the second glass substrate 27 has a substrate overhanging portion 14T that protrudes outward from the outer shape of the first glass substrate 13, and on the substrate overhanging portion 14T, The data electrode 26, the electrical wirings 28 and 29, and the input terminal portion (external connection terminal) 219 made of a plurality of wiring patterns formed independently are preferably formed.
Further, on the substrate overhanging portion 14T, a semiconductor incorporating a liquid crystal driving circuit and the like so as to be conductively connected to the data electrode 26, the electric wirings 28 and 29, and the input terminal portion (external connection terminal) 219. An element (IC) 91 is preferably mounted.
Furthermore, it is preferable that a flexible wiring board 93 is mounted on the end portion of the board extension part 14T so as to be conductively connected to the input terminal part (external connection terminal) 219.

(3) Phase difference plate and polarizing plate In the liquid crystal panel 200 shown in FIG. 2, as shown in FIG. 3, the first glass substrate 13.
It is preferable that a phase difference plate (¼ wavelength plate) 250 and a polarizing plate 251 are disposed at a predetermined position so that a clear image display can be recognized.
Also on the outer surface of the second glass substrate 27, it is preferable that a retardation plate (¼ wavelength plate) 240 and a polarizing plate 241 are disposed.

(4) Basic Configuration of First Substrate (Color Filter Substrate) As shown in FIG. 3, the color filter substrate 12 basically includes a first glass substrate 13,
The coloring layer 16, the light shielding layer 18, and the scanning electrode (first electrode pattern) 19 are preferably used.
Further, when the color filter substrate 12 needs a reflection function, for example, in a transflective liquid crystal display device used for a mobile phone or the like, a gap between the glass substrate 13 and the colored layer 16 is shown in FIG. As shown, the transflective plate 21 having a reflective layer 212a and an opening 212r.
2 is preferably provided.
Furthermore, in the color filter substrate 12, as shown in FIG. 3, a colored layer 16 is formed for each pixel, and a planarizing layer (surface protective layer or overcoat layer) made of a transparent resin such as an acrylic resin or an epoxy resin is formed thereon. ) 215. In this way, a color filter is formed by the colored layer 16 and the planarization layer (surface protective layer) 215. It is also preferable to provide an insulating layer (not shown) for improving electrical insulation.

(5) Colored Layer The colored layer 16 shown in FIG. 3 is usually made to exhibit a predetermined color tone by dispersing colorants such as pigments and dyes in a transparent resin. An example of the color tone of the colored layer is a primary color filter composed of a combination of three colors R (red), G (green), and B (blue), but is not limited to this. ), M (magenta), C (cyan), and other various color tones.
Such a colored layer usually has a predetermined color by applying a colored resist made of a photosensitive resin containing a coloring material such as a pigment or a dye on the surface of the substrate, and removing unnecessary portions by a photolithography technique (etching method). A colored layer having a pattern can be formed.
And when forming the colored layer of a some color tone, the said process is repeated.
Further, as the arrangement pattern of the colored layers, a stripe arrangement is often adopted. In addition to the stripe arrangement, various pattern shapes such as an oblique mosaic arrangement and a delta arrangement can be adopted.

(6) Light-shielding layer As shown in FIG. 3, a light-shielding layer (black matrix or black matrix) is used to improve the contrast at the time of image display in the inter-pixel region between the colored layers 16 formed for each pixel. It may be referred to as a black mask.) 18 is preferably formed.
Examples of such a black matrix 18 include those in which three colorants of R (red), G (green), and B (blue) are dispersed in a resin or other base material, or black pigments or dyes. A material in which a coloring material such as a resin is dispersed in a resin or other base material can be used. In addition, since an excellent shielding effect can be obtained without using a black material such as carbon, an R (red) layer, a G (green) layer, and a B (blue) layer can be obtained using an additive color method. A layer structure is also preferable.

(7) Reflective Layer As shown in FIG. 3, a reflective layer 212a is formed on the surface of the first glass substrate 13 to display an image using external light. The reflective layer 212a is composed of a metal thin film made of aluminum, aluminum alloy, chromium, chromium alloy, silver, silver alloy, or the like.
The reflective layer 212a is provided with a reflective portion having a reflective surface and an opening 212r for each pixel. The reflective portion 212a displays an image using external light, and the opening 212r has an image display. An image can be displayed using transmitted light.

(8) First electrode pattern (scanning electrode)
As shown in FIG. 3, a scanning electrode (first electrode pattern) 19 made of a transparent conductor such as ITO (indium tin oxide) is formed on the planarization layer 215. The scanning electrode (first electrode pattern) 19 is usually preferably configured in a stripe shape in which a plurality of transparent electrodes are arranged in parallel.

(9) Alignment film (first alignment film)
Further, as shown in FIG. 3, a first alignment film 217 made of polyimide resin or the like is formed on the first electrode pattern (scanning electrode) 19.
By providing the alignment film 217 as described above, when the color filter substrate 12 is used in a liquid crystal display device or the like, the alignment control of the electro-optical material (liquid crystal material) can be easily performed.

(10) Basic Structure of Second Substrate (Element Substrate) As shown in FIGS. 2 and 3, the other element substrate facing the color filter substrate 12 (
The second substrate) 14 basically includes a second glass substrate 27, a data electrode 26, a non-linear element such as a TFD (Thin Film Diode) electrically connected to the data electrode 26, and the non-linear element. The pixel electrode 20 is electrically connected and the electrical wirings 28 and 29 for external connection are configured.
As shown in FIG. 3, a second alignment film 224 made of the same polyimide resin or the like as the first alignment film on the first substrate 12 is formed on the data electrode 26.
Further, in the element substrate, similarly to the color filter substrate, a dummy electrode for uniformly adjusting the cell gap is formed in a region where the second electrode pattern is not formed.
In the example of the liquid crystal display device of the first embodiment, the colored layer is provided on the first glass substrate 13. However, the colored layer may be provided on the second glass substrate 27 of the element substrate 14. it can. Furthermore, a three-terminal TFT (Thin Film Transistor) can be used on the element substrate as a nonlinear element instead of the two-terminal TFD.

(11) Second Electrode Pattern As shown in FIG. 2, the data electrode 2 which is one of the second electrode patterns is provided on the element substrate.
6 is provided. As shown in FIG. 2, the data electrode 26 has a plurality of transparent electrodes arranged in a stripe shape.
Further, as shown in FIG. 2, the data electrode is connected to the electrical wiring 29 that has one end side serving as the external connection terminal 219, and is outside the sealing material 230, on the substrate overhanging portion of the second glass substrate 27. It is extended to 14T. Note that the distance between adjacent data electrodes and the height of the data electrodes can be the same as those of the first electrode pattern described above. Therefore, the description here is omitted.
Further, as shown in FIG. 2, the element substrate has an electric wiring 28 which is one of the second electrode patterns.
29 are provided. Usually, the electrical wiring 28 is also configured in a stripe shape in which a plurality of metal films are arranged in parallel.

3. Interface Unit (1) Basic Configuration Next, the basic configuration of the interface unit 4 will be described with reference to FIG. 1, FIG. 4 and FIG.
That is, the interface means 4 is a member for inputting a signal from the outside to the driving circuit. Accordingly, there is no particular limitation as long as a part thereof includes a shield line for transmitting a high-frequency signal or a transmission line corresponding to the shield line. However, as shown in FIG. 93, and a shield wire or a transmission line corresponding to the shield wire is preferably provided on the surface thereof.
This is because the configuration makes it easy to adapt the shape of the interface means to the usage environment, and also facilitates the wiring design for the connection portion with the external device.

Further, regarding the basic configuration of the interface means 4, it is preferable that a shielded wire or a transmission line 50 corresponding to the shielded wire and a non-shielded wire 51 are formed in a predetermined region on the surface of the flexible substrate 93.
This is because a shielded wire or a transmission line equivalent to a shielded wire and a non-shielded wire 51 are provided side by side, and a shielded wire or a transmission wire equivalent to a shielded wire is used for a high-speed signal that is greatly affected by electromagnetic radiation. On the other hand, unshielded wires can be used for low-speed signals that are less affected by electromagnetic radiation.
That is, for signals that require high-speed communication, such as image display system signals, use shielded lines or transmission lines equivalent to shielded lines. Can be used properly, such as using unshielded wires. Therefore, a shielded wire or a transmission line 50 corresponding to the shielded wire and a non-shielded wire 5 at a predetermined place.
1 can be used to minimize the applied voltage for driving, and the power consumption can be reduced.

Regarding the basic configuration of the interface means 4, it is preferable that a coaxial line connector 52 connected to the shield wire 50 is formed at the end of the flexible substrate 93.
This is because the connection position between the coaxial line and the external device can be appropriately selected according to the intended use by adopting such a configuration. Therefore, the arrangement design of the connector portion can be easily performed.
The configuration of the coaxial line connector 52 is not particularly limited, and may be a mechanical connector or an optical connector.

(2) Shielded wire or transmission line equivalent to shielded wire Next, the content of the shielded wire wired to the interface means 4 will be specifically described.
First, although it does not restrict | limit especially regarding the kind of shield wire, For example, it is preferable that at least one of a microstrip line, a coplanar line, and a coaxial line is included.
This is because the wiring design can be reliably performed at low cost by using such a general-purpose shield wire that has been used.

Here, FIG. 4 (a) shows a case where a microstrip line is used as the shield line.
The AA sectional view in is shown. The microstrip line 50a is formed on the surface of the flexible substrate 93a, and the ground wiring 53a is formed on the surface on the opposite side so as to be aligned with the microstrip line 50a.
Therefore, the characteristic impedance Z, which will be described later, is adjusted by appropriately adjusting the line thickness, line width, line interval, thickness of the flexible substrate, the form of the ground wiring, the dielectric constant of the resin constituting the flexible substrate, and the like. Considering this, impedance matching can be taken.

FIG. 4B shows a cross-sectional view taken along line AA in FIG. 1 when a coplanar line is used. The coplanar lines 50b are formed on the same surface of the flexible substrate 93b, and the coplanar lines 50b and the ground wirings 53b are alternately arranged in the planar direction.
Therefore, impedance matching can be achieved by appropriately adjusting the line thickness, line width, line interval, flexible board thickness, dielectric constant of the constituent resin of the flexible board, and the like of the coplanar line 50b. Moreover, since wiring can be performed on the same surface, the overall thickness can be reduced.

FIG. 4C is a cross-sectional view taken along the line AA in FIG. 1 when the coaxial line 50c is used. The coaxial line 50c is provided with a shield portion coaxially around the conducting wire.
Therefore, in the case of the coaxial line 50c, the diameter of the conductive wire, the diameter of the shield portion, the distance between the conductive wire and the shield portion, the thickness of the flexible substrate, the dielectric constant of the resin constituting the flexible substrate, the distance between adjacent coaxial lines, etc. By appropriately adjusting the impedance, impedance matching can be achieved. Further, since it has a structure in which the periphery of the conducting wire is covered with a shield part, it is particularly suitable for transmission of a high-frequency signal.
In addition, although not shown in figure, it can also be set as the coaxial line which covers the circumference | surroundings of a plate-shaped conducting wire with a shield part, and has a flat plate shape as a whole. With such a configuration, the entire substrate can be thinned.

FIG. 4D is a cross-sectional view taken along line AA in FIG. 1 when the coaxial line 50d and the microstrip line 50d ′ are used in combination. In other words, the coaxial line 50d and the microstrip line 50d ′ can be formed in combination on the surface of the flexible substrate 93d. At this time, the arrangement of the coaxial line and the microstrip line in the plane direction can be arbitrarily selected. As an example, FIG. 4D shows a configuration in which coaxial lines 50d are arranged at both ends and a microstrip line 50d ′ is arranged therebetween.

FIG. 5A shows a plan view when the UTP line 50r is arranged on the flexible substrate 93r, and FIG. 5B shows a cross-sectional view along AA in FIG. 5A. .
The UTP line 50r is composed of a conducting wire (+ side) 51r, a conducting wire (− side) 52r, and an insulating film 53r. The pair of conducting wires are combined in a spiral shape to form a flexible substrate 93r. It is formed on the surface. Here, the UTP line is a transmission line that includes a pair of conductors combined in a spiral shape and does not include a shield part, and can be used without providing a special ground wiring on the flexible substrate. .
Therefore, in the case of the UTP line 50r, impedance matching can be achieved by appropriately adjusting the lead wire diameter, the helical pitch, and the like. In addition, since it has a spirally combined structure, it is possible to minimize the influence of electromagnetic wave radiation generated from each conductor, which is particularly suitable for transmission of high-frequency signals.

Further, when a plurality of shielded wires or transmission lines corresponding to the shielded wires are wired on the interface means 4, it is preferable to equalize their impedances and take so-called impedance matching.
This is because by taking impedance matching, transmission loss of a high frequency signal resulting from impedance mismatch can be minimized. Therefore,
By taking impedance matching, a high-frequency signal can be transmitted accurately and stably.

In addition, when impedance matching is performed, it is preferable that the characteristic impedance Z of each shield line or transmission line corresponding to the shield line is calculated, and the wiring is designed based on such value.
More specifically, the characteristic impedance Z calculated from the following equation (1) is calculated and adjusted for all shield wires arranged on the flexible substrate or transmission lines corresponding to the shield wires. That is, impedance matching can be achieved by designing the wiring so that the difference between the maximum value and the minimum value of the calculated values is within a desired range.
Z = 377 / [(w / h) × εr ^1/2 [1+ (1.735εr ^−0.0724 ) × (w / h) ^−0.836 ]] (1)
Here, w is a line width (mm) of a shielded wire or a transmission line corresponding to the shielded wire, h is a flexible substrate thickness (mm), and εr is a relative dielectric constant of a constituent resin of the flexible substrate (
In addition, h is a value sufficiently larger than the thickness of the shielded wire or the transmission line corresponding to the shielded wire.

FIG. 6 shows an example of a method of adjusting the characteristic impedance using the above formula (1) when a microstrip line is used as a shield line or a transmission line corresponding to the shield line.
FIG. 6A shows a case where the microstrip line 50n having the width w1 is arranged on the substrate of the flexible substrate 93n having the thickness h1. Here, when it is desired to change the characteristic impedance of the microstrip line 50n to a desired value, as shown in FIG.
By reducing the width w1 of the microstrip line while keeping the thickness of the flexible substrate fixed, the microstrip line 50p having the width w2 can be changed. On the other hand, as shown in FIG. 6C, by changing the thickness h1 of the flexible substrate while the width w1 of the microstrip line is fixed, it can be changed to the flexible substrate 93q having the thickness h2. Therefore, by making such a configuration change, equation (1)
The value of the variable w / h at, changes, and the value of the characteristic impedance can be adjusted to a desired value.
FIG. 7 shows a graph of the relationship between the variable w / h and the characteristic impedance Z expressed by equation (1). As can be understood from the graph, it can be seen that the characteristic impedance Z tends to decrease as the variable w / h increases. Therefore, in the present invention, this relationship can be used when impedance matching is performed.

In configuring the electro-optical device of the present invention, it is preferable that a ground wire for a shielded wire or a transmission wire corresponding to the shielded wire is formed in a part of the interface means.
This is because, by adopting such a configuration, it is possible to easily perform a short circuit of the shield wire without providing a ground connection on the flexible substrate. as a result,
High-frequency signals can be transmitted accurately and stably. That is, as shown in FIG. 1, by providing the ground wiring 54 at the connection interface where the flexible substrate 93 and the end of the overhanging portion 14T are connected, the shield can be provided without arranging the ground wiring on the flexible substrate. It becomes possible to short-circuit a transmission line corresponding to a wire or a shielded wire.

In configuring the electro-optical device of the present invention, it is preferable to set the communication speed for transmitting a signal via a shielded wire or a transmission line corresponding to the shielded wire to a value of 180 Mbps or more.
The reason for this is not only that predetermined high-speed communication is possible, but also that the applied voltage for driving can be suppressed to reduce the power consumption of the electro-optical device.
Further, with such a configuration, it is possible to suitably select a transmission line that matches the required communication speed. Accordingly, the applied voltage for driving can be minimized, and the power consumption can be further reduced.
As the communication speed increases, the amount of signal transmission per unit time increases.
It has been found that a value of 0 Mbps or more can be suitably used as an image display system signal. In addition, with such a communication speed, there is an advantage that it is not necessary to perform an excessive shielding process. On the other hand, it has been found that when the communication speed becomes a value of 1 Gbps or more, it is possible to perform a predetermined shielding process, although a better image display can be performed.

(3) Unshielded line Next, the unshielded line wired to the interface means 4 will be described in detail.
Although partly described above, it is preferable to use a shielded wire or a transmission line equivalent to a shielded wire and a non-shielded wire for the interface means. More preferably, the unshielded wire is disposed only in the region.
Here, FIG. 8A shows a shielded line or a transmission line 50e corresponding to the shielded line and a non-shielded line 51e formed on the surface of the flexible substrate 93e, and the non-shielded line 51e is a one-side region in the plane direction. Fig. 1 shows a configuration in which blocks are collected and arranged.
By adopting such a configuration, it is possible to minimize electromagnetic interference even with a non-shielded wire having low electromagnetic wave resistance. Impedance matching can be easily achieved by collecting the same type of lines.
Here, an example in which a microstrip line is used as a shield line is shown. Therefore, the ground wiring 53e is arranged on the surface of the flexible substrate 93e on the side opposite to the side where the microstrip line 50e is arranged so that the vertical position is aligned with the microstrip line. In addition, the type of unshielded wire is not particularly limited, but it means a lead wire that has not taken any special countermeasure against electromagnetic interference.

In FIG. 8B, a shielded line or a transmission line 50f corresponding to the shielded line and a non-shielded line 51f are formed on the surface of the flexible substrate 93f, and the non-shielded line 51f is formed in the central region in the planar direction. A configuration arranged in a block form is shown.
By adopting such a configuration, it is possible to minimize electromagnetic interference even with a non-shielded wire having low electromagnetic wave resistance. In addition, since shielded wires or transmission lines corresponding to shielded wires can be arranged at both ends, the influence of electromagnetic wave radiation from the shielded wires can be minimized.
Here, an example in which a microstrip line is used as a shield line or a transmission line corresponding to the shield line is shown. Therefore, as shown in the lower part of FIG. 8B, the ground wiring 53f is aligned with the microstrip line on the surface of the flexible substrate 93f opposite to the side where the microstrip line 50f is arranged. So that it is arranged.

Further, in FIG. 8C, a shielded line or a transmission line 50g corresponding to the shielded line and an unshielded line 51g are formed on the surface of the flexible substrate 93g, and the unshielded line 51g is formed in both side regions in the plane direction. The arrangement is shown.
By adopting such a configuration, it becomes possible to concentrate and arrange shielded wires or transmission lines corresponding to shielded wires in one place, so that electromagnetic interference can be minimized.
Here, an example in which a microstrip line is used as a shield line or a transmission line corresponding to the shield line is shown. Therefore, as shown in the lower part of FIG. 8C, the ground wiring 53f is aligned with the microstrip line on the surface of the flexible substrate 93f opposite to the side where the microstrip line 50f is arranged. So that it is arranged.

In FIG. 8D, a shielded line or transmission line 50h corresponding to the shielded line and a non-shielded line 51h are formed on the surface of the flexible substrate 93h, and a transmission line 50h equivalent to the shielded line or shielded line is formed. A configuration in which the non-shielded wires 51h are alternately arranged in the planar direction is shown.
This is because, by adopting such a configuration, it is possible to minimize the influence of electromagnetic wave radiation due to the high-frequency signal, and high-precision and stable transmission of the high-frequency signal can be performed. or,
This is because it is possible to provide a wide interval between the same type of lines, so that the design accuracy is moderated and wiring processing is facilitated.
Here, an example in which a microstrip line is used as a shield line or a transmission line corresponding to the shield line is shown. Therefore, as shown in the lower part of FIG. 8D, the ground wiring 53h is aligned with the microstrip line on the surface of the flexible substrate 93h opposite to the side where the microstrip line 50h is arranged. So that it is arranged.

Further, in the interface means 4, it is preferable to determine the shape and arrangement of the shielded wire or the transmission line corresponding to the shielded wire and the non-shielded wire corresponding to the form of the flexible substrate 93.
This is because the transmission distance of the high-frequency signal that causes electromagnetic interference is shortened by arranging the shield line or the transmission line corresponding to the shield line so that the wiring length is the shortest. That is, with such a configuration, not only low-frequency signals but also high-frequency signals can be accurately and stably transmitted at high speed.
Here, FIG. 9A shows a plan view and a cross-sectional view taken along line AA when a microstrip line is arranged on an L-shaped flexible substrate. Such a flexible substrate 93
On i, a microstrip line 50i and an unshielded line 51i are formed on the same surface. In the flexible substrate, the microstrip line is formed on a straight line connecting the input side end and the output side end with the shortest distance. That is, in the case of the configuration shown in FIG. 9A, when the planar shape of the flexible substrate is L-shaped,
It arrange | positions so that the length of a microstrip line may become comparatively short.

FIG. 9B shows a plan view and a BB cross-sectional view when a microstrip line is used on a T-shaped flexible substrate. Such a flexible substrate 93
On j, a microstrip line 50j and a non-shielded line 51j are formed on the same surface. In the flexible substrate, the microstrip line is formed on a straight line connecting the input side end and the output side end with the shortest distance. That is, in the case of the configuration shown in FIG. 8B, when the planar shape of the flexible substrate is T-shaped,
Two microstrip lines are equally arranged in the left-right direction so that the length of the microstrip line is relatively short.

FIG. 9C shows a plan view and a CC cross-sectional view when a microstrip line is used on a cross-shaped flexible substrate. Such a flexible substrate 93
On k, a microstrip line 50k and an unshielded line 51k are formed on the same surface. In the flexible substrate, the microstrip line is formed on a straight line connecting the input side end and the output side end with the shortest distance. That is, in the case of the configuration shown in FIG. 9C, when the planar shape of the flexible substrate is a cross shape,
The microstrip lines are arranged in three directions so that the length of the microstrip line is relatively short.

Further, when a shielded wire or a transmission line equivalent to a shielded wire and a non-shielded wire are used in combination, as shown in FIGS. 10A to 10B, the interface means 4 uses a shielded wire or a transmission wire equivalent to a shielded wire. And the non-shielded wires are preferably arranged in multiple layers in the vertical direction.
The reason for this is that by adopting such a configuration, it is possible to minimize the influence of electromagnetic radiation, and high-frequency signals can be transmitted with high accuracy and stability. In addition, connection means such as wire bonding can be used for the connection portion with the external device, and the shape of the connection portion becomes less restrictive so that wiring design is facilitated.

Here, FIG. 10A shows a state in which the flexible substrate 93L includes a shielded wire or a transmission line 50L corresponding to the shielded wire, and a non-shielded wire 51L on the surface. FIG. 10A shows an example in which a microstrip line is used as a shield line or a transmission line corresponding to the shield line. Therefore, flexible substrate 93L
On the surface of the wire, the ground wire 53L is connected to the shield wire 5 on the side where the non-shield wire is not disposed.
It is arranged so that the vertical position is aligned with 0L. With this arrangement, it is easy to leave a gap between the shielded wire and the non-shielded wire. As a result, it is easy to take countermeasures against electromagnetic interference in the process of wiring design, such as designing non-shielded wires that are easily affected by electromagnetic radiation only at positions where they are not easily affected.

FIG. 10B shows a state in which two flexible substrates 93m and 93m ′ are provided. A shielded wire or a transmission line 50m corresponding to the shielded wire is wired on the surface of the flexible substrate 93m, and on the surface of the flexible substrate 93m ′,
A non-shielded wire 51m is wired. Further, FIG. 10B shows an example in which a microstrip line is used as a shield line or a transmission line corresponding to the shield line. Therefore, the ground wiring 53m is arranged so that the vertical position is aligned with the shield line or the transmission line 50m corresponding to the shield line so as to be sandwiched between the flexible boards 93m and 93m ′. With such an arrangement, the ground wire provided between the shielded wire and the non-shielded wire provides an electromagnetic wave shielding effect, so that the influence of electromagnetic wave radiation can be minimized. Furthermore, a predetermined noise reduction effect can be obtained for the unshielded wire.

(4) Connector In the interface means 4, as shown in FIG. 1, a connector 52 for connection with an external device is disposed at the end of the shielded wire or the transmission line 50 corresponding to the shielded wire. The connector 52 is arranged on the flexible substrate 93, and the arrangement location can be arbitrarily selected. Further, it can be mounted directly on the overhanging portion 14T by COG. Therefore, it is possible to easily perform a wiring design that matches the connection location with the external device.
In connecting the flexible board and the external device, it is preferable to provide a mechanical connector 93T for external connection at the end of the flexible board 93 as shown in FIG. Further, the mechanical connector 93T and the connector insertion portion 2 provided in the external device 270
It is also preferable that 70T is mechanically and electrically connected. For example, the mechanical connector 93T and the connector insertion portion 270T are fixed by the fixing jig 274 by inserting the mechanical connector 93T into the gap 275 provided in the connector insertion portion 270T. Therefore, the upper terminal 272 and the lower terminal 273 provided in the connector insertion portion 270T are in contact with and electrically connected to the shielded wire 50 or the non-shielded wire 51 disposed on the flexible substrate 93, respectively. It becomes possible. That is, by adopting such a configuration, the contact resistance of the connection portion is reduced, and more accurate and stable signal transmission is possible. In addition, since the connector can be easily attached and detached, it is possible to prevent mechanical deterioration when the attachment and detachment are repeated.

(5) External Device As shown in FIG. 12, the flexible substrate 93 has an external device 400 at its end.
Connected with. The external device 400 is a CPU 4 that interprets and executes an input command.
01, a signal processing circuit 402 for transmitting a signal from the CPU 401 to the driving circuit 91, and a power source 403. That is, as an external command, for example, display ON / OFF
When a signal for screen switching or the like is input, it is converted into a digital signal by the CPU 401 and transferred to the signal processing circuit 402. Then, in the signal processing circuit 402, it is converted into specific display information, for example, by collating with a built-in storage means. Thereafter, the signal is transmitted to the driving circuit 91 provided in the liquid crystal display device 100 via the interface unit 4.
Here, the signal processing circuit 402 further includes a high-speed signal processing circuit 404 and a low-speed signal processing circuit 4.
05 is preferable. This is because the operation mode can be switched as appropriate by adopting such a configuration. That is, the CPU 401 can operate with less power consumption by switching the operation mode so that the driving voltage and the operating frequency are suitable for the high-speed signal and the low-speed signal.

(6) Temperature Compensation Circuit As shown in FIG. 1, it is preferable that a temperature compensation circuit is provided on a part of the flexible substrate or a part of the driving circuit.
The reason for this is that even if the ambient temperature has changed due to such a configuration,
This is because high-frequency signals can be accurately and stably transmitted at high speed.
Here, it is preferable that the temperature compensation circuit 300 constitutes a circuit as shown in FIG. 13, for example. More specifically, using the temperature characteristic of the temperature-dependent resistor 356, the first voltage V1 divided by the temperature-dependent resistor 356 and the resistor 357, the resistor 358, and the resistor 359 are used.
The second voltage V <b> 2 that has been divided by is compared in the comparison circuit 367 including the first transistor 361 and the second transistor 362. Next, the output is sent to the CPU 365 as the voltage V3, and the CPU 365 performs a determination process to determine whether or not the environmental temperature is equal to or higher than a predetermined temperature, and the result is sent to the drive circuit 91 to cope with the temperature change. Display information can be transmitted.

14A to 14C show an example of a mechanism for changing the application voltage and application time of the drive signal so as to follow the change when the temperature change occurs.
For example, as shown in FIG. 14 (a), when the environmental temperature is 30 ° C. or lower, the value of the applied voltage is increased or the value shown in FIG. Thus, it is preferable to lengthen the application time as the temperature decreases. Furthermore, as shown in FIG. 14C, it is also preferable to change the product of the applied voltage and the applied time with respect to the environmental temperature.

[Second Embodiment]
FIG. 15 is a schematic configuration diagram showing the overall configuration of the electronic apparatus of the present embodiment. The electronic apparatus includes a liquid crystal panel 20 as an electro-optical device and a control unit 200 for controlling the liquid crystal panel 20. In FIG. 14, the liquid crystal panel 20 includes a panel structure 20 a and a semiconductor element (
IC) or the like, and is divided conceptually into a drive circuit 20b. Control means 2
00 preferably includes a display information output source 201, a display processing circuit 202, a power supply circuit 203, and a timing generator 204.
The display information output source 201 includes a ROM (Read Only Memory) and a RAM (Random Access).
Memory), a storage unit composed of a magnetic recording disk, an optical recording disk, and the like, and a tuning circuit that tunes and outputs a digital image signal. Based on various clock signals generated by the timing generator 204, It is preferable that the display information is supplied to the display processing circuit 202 in the form of a predetermined format image signal or the like.

The display processing circuit 202 includes various known circuits such as a serial-parallel conversion circuit, an amplification / inversion circuit, a rotation circuit, a gamma correction circuit, and a clamp circuit, and executes processing of input display information to display the image. Information is preferably supplied to the drive circuit 20b together with the clock signal CLK. Furthermore, the drive circuit 20b preferably includes a first electrode drive circuit, a second electrode drive circuit, and an inspection circuit. The power supply circuit 203 has a function of supplying a predetermined voltage to each of the above-described components.
In the electronic apparatus according to the present embodiment, a part of the interface unit includes a shielded line for transmitting a high-frequency signal or a transmission line corresponding to the shielded line. An electro-optical device capable of transmitting a signal at high speed is provided, and a bright and excellent image display can be obtained as an electronic device that can realize low power consumption.

According to the present invention, since a part of the interface means includes a shielded line for transmitting a high-frequency signal or a transmission line corresponding to the shielded line, the high-frequency signal can be transmitted to the drive circuit at a high speed. Can now. Accordingly, with the increase in the transmission speed of high-frequency signals, it has become possible to contribute to the improvement of image characteristics and the reduction of power consumption of the electro-optical device.
Therefore, an electro-optical device such as a liquid crystal display device provided with a TFD element or a TFT element, an electronic device,
For example, mobile phones and personal computers, liquid crystal televisions, viewfinder type / monitor direct view type video tape recorders, car navigation devices, pagers, electrophoresis devices, electronic notebooks, calculators, word processors, workstations, videophones, POS terminals, electronic devices with touch panels, devices with electron-emitting devices (FED: Fie
It can be widely applied to ld Emission Display and SCEED (Surface-Conduction Electron-Emitter Display).

It is a schematic perspective view of the liquid crystal display device provided with the predetermined | prescribed interface means. It is a schematic perspective view of the liquid crystal panel which comprises a liquid crystal display device. It is a schematic sectional drawing which shows a liquid crystal display device typically. It is a figure provided in order to demonstrate the arrangement configuration of the shield line in an interface means. It is a figure provided in order to demonstrate the arrangement structure of the UTP line in an interface means. It is a figure provided in order to demonstrate the relationship between the line | wire width of the shield line in a microstrip line, and the thickness of a flexible substrate. It is a characteristic view provided in order to demonstrate the relationship between the line width of the shield line in a microstrip line, the ratio of the thickness of a flexible substrate, and characteristic impedance. It is a figure provided in order to demonstrate the arrangement configuration of the shielded wire and the non-shielded wire in the interface means. It is a figure provided in order to demonstrate the relationship between the planar shape in an interface means, and the wiring of a shield wire. It is sectional drawing with which it uses in order to demonstrate the arrangement configuration of the shield wire in an interface means, a non-shield wire, and a flexible substrate. It is a figure provided in order to demonstrate the connection of an interface means and an external device. It is a block diagram provided in order to demonstrate the relationship between a liquid crystal display device and an external device. It is a figure provided in order to demonstrate the structure of a temperature compensation circuit. It is a characteristic view provided in order to demonstrate the relationship in temperature in a temperature compensation mechanism, a voltage, and time. 1 is a block diagram provided for explaining a schematic configuration of an electronic apparatus including an electro-optical device according to the invention. It is a figure provided in order to demonstrate the liquid crystal display device provided with the conventional shield wire.

Explanation of symbols

4: interface means, 12: first substrate, 13: first glass substrate, 14: second substrate, 27: second glass substrate, 19: first wiring pattern (scanning electrode), 20: first 2 wiring pattern (pixel electrode), 26: data line, 28: lead-out wiring, 50: shielded line or transmission line equivalent to shielded line, 51: unshielded line, 53: connector, 53: ground wiring,
93: Flexible substrate, 91: Driving circuit, 100: Liquid crystal display device, 200: Liquid crystal panel, 230: Seal material, 232: Liquid crystal material, 300: Temperature compensation circuit

Claims (8)

In an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside,
The interface has a flexible substrate,
The flexible substrate is formed with a plurality of shield wires and non-shield wires for transmitting high-frequency signals on the surface thereof,
The shielded wire, in plan view, the electro-optical apparatus characterized by being arranged to concentrate on one end side in the width direction of the flexible substrate. In an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside,
The interface has a flexible substrate;
The flexible substrate is formed with a plurality of shield wires and non-shield wires for transmitting high-frequency signals on the surface thereof,
The shielded wire, in plan view, the electro-optical device, characterized in that arranged at both ends in the width direction of the flexible substrate. In an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside,
The interface has a flexible substrate;
The flexible substrate is formed with a plurality of shield wires and non-shield wires for transmitting high-frequency signals on the surface thereof,
The shielded wire, in plan view, the electro-optical apparatus characterized by being arranged in the central portion in the width direction of the flexible substrate. In an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside,
The interface has a flexible substrate;
The flexible substrate is formed with a plurality of shield wires and non-shield wires for transmitting high-frequency signals on the surface thereof,
The shielded wire, in plan view, the electro-optical apparatus characterized by being arranged alternately with the non-shielded wire in the width direction of the flexible substrate. In an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside,
The interface has a flexible substrate including a bent portion at least in part,
The flexible substrate has a shield wire for transmitting a high-frequency signal on its surface and a plurality of unshielded wires arranged along the shield wire,
The shielded wire, in plan view, the is disposed inside the bent portion, the non-shielded lines, to be placed on the outside of the bent portion with respect to the shielded wire Electro-optical device characterized. In an electro-optical device including a substrate, an electro-optical material held on the substrate, a driving circuit, and interface means for inputting a signal to the driving circuit from the outside,
The interface includes a first flexible substrate and a second flexible substrate,
The first flexible substrate and the second flexible substrate are arranged in a state of sandwiching a ground wire,
The first flexible substrate is formed on a surface opposite to a surface sandwiching the ground wire so that a shield wire for transmitting a high-frequency signal overlaps the ground wire in a plan view.
The electro-optical device, wherein the second flexible substrate has a non-shielded wire formed on a surface opposite to a surface sandwiching the ground wire.   The electro-optical device according to claim 6, wherein the non-shielded wire is disposed at a position that does not overlap the shielded wire and the ground wire in a plan view.   An electronic apparatus comprising the electro-optical device according to claim 1.

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