JPH0876136A - Liquid crystal display - Google Patents

Abstract

PURPOSE: To provide a liquid crystal display device having, leader wiring of which area use efficiency is high which is short and low in resistance. CONSTITUTION: This liquid crystal display device has plural pieces of electrodes 2 for display which are wired respectively in parallel on an electrode substrate 12 and terminals 3 of respective electrodes 2 which are drawn out to the ends of the electrode substrate 12 and are connected to TCPs. The pitches of the terminals 3 are narrower than the pitches of the electrodes 2. The device has the leader wirings connecting the respective electrodes 2 to the respective terminals 3. The leader wirings have the parts extended straight from the electrodes 2, the parts extended straight from the terminals 3 and the diagonal straight wirings 1 which respectively connect the two extended parts and are respectively nearly parallel. The leader wirings are formed by adjusting the length of the two extended parts and the width of the diagonal straight wirings 1 in such a manner that the wiring resistances of the leader wirings are respectively nearly equaled.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device of a simple matrix type or an active matrix type, and more particularly to a liquid crystal display device having a lead wiring for connecting an electrode of a liquid crystal display element to a driving element.

[0002]

2. Description of the Related Art A liquid crystal display device is, for example, an insulating substrate (an electrode substrate and an insulating substrate) made of two transparent glasses with a predetermined gap so that the surfaces on which a transparent pixel electrode for display and an alignment film are laminated face each other. (Hereinafter referred to as "), and the two substrates are bonded together by a sealing material provided in a frame shape around the edge between the two substrates, and at the same time, the sealing material between the two substrates is sealed from the liquid crystal sealing port provided in a part of the sealing material. Liquid crystal display device (ie liquid crystal display unit; liquid crystal display panel; LCD: liquid) in which liquid crystal is enclosed and sealed inside and polarizing plates are provided outside both substrates.
A crystal display) and a backlight disposed below the liquid crystal display element to supply light to the liquid crystal display element,
A drive circuit board for the liquid crystal display element, which is arranged outside the outer peripheral portion of the liquid crystal display element, a frame-shaped body which is a molded product for holding each of these members, and each of these members. It is configured to include a metal frame and the like that have been opened.

The liquid crystal display element and the driving circuit board are, for example, a tape carrier package (hereinafter referred to as TCP) on which a semiconductor integrated circuit chip for driving the liquid crystal display element is mounted.
It is electrically connected by. More specifically, the large number of output terminals of the circuit board and the large number of input terminals of the TCP (input side outer leads) are connected by soldering, and the large number of output terminals of the TCP (output side outer leads) are connected to the display electrodes. Connected to a large number of input terminals of the liquid crystal display element to be connected (arranged at one end of the transparent glass substrate constituting the liquid crystal display element, that is, the end portion on the electrode substrate surface) by an anisotropic conductive film. . In addition, many input terminals of the semiconductor integrated circuit chip mounted on the TCP are
Connected to many output side inner leads of TCP, on the other hand, many output terminals of the semiconductor integrated circuit chip are TCP
Is connected to many input side inner leads.

Documents describing such a liquid crystal display device include, for example, JP-A-61-214548,
For example, Japanese Utility Model Laid-Open No. 2-13765 is cited.

[0005]

FIG. 16 shows a part of wiring formed on an electrode substrate constituting a conventional liquid crystal display element, that is, a terminal for connecting a display electrode and a TCP electrode, and It is a principal part schematic plan view which shows the lead-out wiring which connects both.

Reference numeral 12 denotes a liquid crystal display element (not shown here).
11, the electrode substrate made of an insulating substrate made of one transparent glass constituting the reference numeral 62 reference) in FIG. 14, 2 ₁ ~
Reference numeral 2 ₈ is a display electrode formed on the surface of the electrode substrate 12 and formed of a transparent conductive film and wired in parallel to form a pixel.
_{1-3 8} TCP is a drive element (not shown here. FIG. 10, reference numeral 10 in FIG. 11) of the electrode (the output side outer lead) and connected thereto terminal (connection electrode, i.e.,
Input terminals) ₁₁ to ₁₈ are diagonal straight lines which are terminal lead-out lines connecting the display electrodes 2 and the terminals 3, and 71 is a TC
A TCP alignment mark when P is mounted on the electrode substrate 12, and 72 is one T mounted on the electrode substrate 12.
The center line of the terminal group corresponding to CP, 52 is a portion where a sealing material is provided.

In the electrode substrate 12 constituting the liquid crystal display element, the arrangement pitch of the TCP electrodes is normally narrower than the arrangement pitch of the display electrodes 2 arranged in parallel, that is, the TCP electrodes are connected to the electrodes. The pitch of the terminals 3 is smaller. Therefore, the lead wiring that connects the display electrode 2 and the terminal 3 is the diagonal linear wiring 1. As shown in FIG. 16, in the conventional lead wiring, the diagonal straight wiring 1 (with respect to the display electrode 2 or the terminal 3) is used.
Both the angle and the width of the diagonal linear wiring 1 are adjusted so that the wiring resistances of the lead wirings are equal to each other. Such lead wires are called radial wires.

[0008] Such a conventional technique has the following problems.

That is, there is a problem that the area utilization efficiency (wiring efficiency) of the lead wiring in the electrode substrate 12 is low, the length of the lead wiring is long, and the wiring resistance is large. When attempting to shorten the lead wire, the width of the lead wire has to be narrowed in order to secure a clearance (interval) between the lead wires, which causes a problem that the wiring resistance increases. At present, the wiring resistance of the lead wiring is, for example, 500 to 1 kΩ. 500-70 of output resistance of semiconductor IC chip for driving
Large compared to 0Ω.

Further, since a plurality of terminals (electrodes) of the TCP, which are arranged in a line on the end portion of the electrode substrate 12, are connected to each other, a group of terminals 3 connected to each other is provided.
Depending on the film thickness of the terminal 3 made of the (indium-tin-oxide; Nesa) film, a difference in height can be made between the portion with the terminal 3 and the portion without the terminal 3. The film thickness of ITO is as thick as 0.2 to 0.3 μm. As a result, when the liquid crystal display element is mass-produced, this shape is transferred to a rubbing roller that performs an alignment process (rubbing) on the alignment film formed on the display electrode 2, and when the alignment process is performed using this rubbing roller, the alignment is performed. The film has uneven rubbing streaks, and as a result, there is a problem that display quality is deteriorated.

Further, since the diagonal linear wiring 1 of the lead-out wiring is laid out in a radial pattern, the interval between the diagonal linear wirings 1 becomes narrower from the display electrode 2 toward the terminal 3, as shown in FIG. Occurs. As a result, the inside of the sealing material 52 of the completed liquid crystal display element (the side where the liquid crystal is present)
Therefore, there is a problem that uneven light and shade is formed in a portion that is a non-lighting portion outside the display portion (lighting portion), that is, a so-called frame portion, which should originally be uniform black. .

Further, a plurality of display electrodes 2 in the display section
Are wired in parallel at equal intervals, so that the wiring density is uniform. On the other hand, the radial diagonal linear wiring 1 is not uniform in wiring density as described in, and therefore, in particular, the STN
(Super twisted nematic) -High precision gap (± 0.1μm) between both electrode substrates, like LCD
In a liquid crystal display device that requires, the effective density at which the spacer for creating the gap functions has a great influence. Therefore, in the conventional radial diagonal linear wiring 1, since the wiring density is generally lower than that of the display portion, color unevenness due to the gap variation in the frame portion occurs. That is, as described above, the transparent electrode is usually made of a thick ITO film having a film thickness of 0.2 to 0.3 μm. Since the display electrodes 2 and the diagonal linear wirings 1 made of the ITO film of the upper and lower electrode substrates support the spacers, the spacers in the portions without electrodes are free, and there is a problem that the gap control does not work.

Documents describing such a technique include, for example, JP-A-3-289626 and JP-A-4-28926.
70627, JP-A-4-170522, JP-A-4-170522.
No. 369622 and JP-A No. 5-127181.

It is a first object of the present invention to provide a liquid crystal display device having a short lead wire having a high resistance in area utilization and having a short resistance.

A second object of the present invention is to provide a liquid crystal display device in which rubbing line unevenness does not occur in the display section.

A third object of the present invention is to provide a liquid crystal display device having a uniform black non-lighting area without uneven shading in the frame portion.

A fourth object of the present invention is to provide a liquid crystal display device in which the gap between both substrates can be well controlled and color unevenness does not occur.

[0018]

In order to achieve the first object, the present invention provides a plurality of electrodes, each of which is wired in parallel on a substrate, and is drawn out to an end of the substrate, and A terminal of each of the electrodes connected to the driving element,
In a liquid crystal display device including a liquid crystal display element in which the pitch of the electrodes is different from the pitch of the terminals, and a lead wire connecting the electrodes and the terminals is provided, the lead wires are the electrodes. From the terminal, a portion directly extending from the terminal, and the two extended portions are respectively connected to each other, and each is composed of diagonal straight lines that are substantially parallel to each other. To be approximately equal,
It is characterized in that it is formed by adjusting the lengths of the two extended portions and the width of the diagonal linear wiring.

Further, according to the present invention, a plurality of electrodes, each of which is wired in parallel on the insulating substrate, and a terminal of each of the electrodes, which is drawn out to an end portion of the insulating substrate and is connected to a driving element, are provided. Having a smaller pitch of the terminals than the pitch of the electrodes, and a liquid crystal display device comprising a liquid crystal display element having diagonal straight lines connecting the electrodes and the terminals, A portion directly extended from the electrode and a portion directly extended from the terminal are respectively connected by the diagonal linear wirings having substantially the same angle with respect to the electrode or the terminal, and the two extended portions and the diagonal linear wiring are included. The lengths of the two extended portions and the width of the diagonal linear wiring are calculated and formed so that the wiring resistances are substantially equal to each other.

Further, it is characterized in that the interval lengths of the portions directly extended from the adjacent electrodes are substantially equal to each other.

Further, it is characterized in that the distances between the adjacent diagonal linear wirings are substantially equal to each other.

Further, in order to achieve the second to fourth objects, the present invention is that a plurality of the driving elements are mounted side by side on the substrate so as to be connected to the terminals and connected to the respective driving elements. A terminal group composed of a plurality of the terminals arranged on the substrate at a second interval wider than the first interval between the terminals, and a first group is provided at a position separated by the second interval. It is characterized in that a dummy electrode is formed.

Further, the first dummy electrode includes at least one dummy parallel electrode formed at substantially the same pitch and width as the terminals and substantially in parallel with the terminals.

Further, the first dummy electrode includes a dummy diagonal straight line electrode substantially parallel to the diagonal straight line wiring formed between the outermost diagonal straight line wirings of the adjacent terminal groups. .

The first dummy electrode has a plurality of dummy parallel electrodes formed at substantially the same pitch and width as the terminals and substantially in parallel with the terminals.
It is characterized by comprising at least two dummy diagonal straight line electrodes substantially parallel to the diagonal straight line wirings on both sides formed between the outermost diagonal straight line wirings of the adjacent terminal groups.

Further, in order to achieve the third and fourth objects, according to the present invention, a second dummy electrode is formed between the adjacent terminal or a portion directly extended from the terminal. Characterize.

Further, it is characterized in that the second dummy electrode and the terminals on both sides thereof or the portions directly extended from the terminals have substantially equal intervals.

The distance between the second dummy electrode and the terminals on both sides of the second dummy electrode or a portion of the second dummy electrode directly extended from the terminal is substantially equal to each other, and the distance is equal to the distance between the adjacent diagonal electrodes. It is characterized in that it is almost equal to the length of the interval between the straight wirings.

Further, the first and second dummy electrodes include at least one material layer which is the same as the terminal.

Further, of the two substrates, at least a part of the terminals, the lead wires, and the dummy electrodes formed at the end portions of one of the substrates are formed on the opposite surfaces of the other substrate. It is characterized by

[0031]

Since the area utilization efficiency (wiring efficiency) of the lead wiring can be improved by forming the lead wiring as described above, the length of the lead wiring can be shortened. The wiring resistance of 1 kΩ can be reduced by about 30 to 40%. Further, since the reduction can be provided as a margin of the on-resistance of the driving semiconductor IC chip, the size of the semiconductor IC chip can be reduced. Furthermore, since the length of the lead-out wiring can be made shorter than in the conventional case, the size of the liquid crystal display element can be reduced. As a result, the manufacturing cost can be reduced. Further, since the wiring resistance is reduced, the distortion of the waveform driving the liquid crystal and the distortion of the crosstalk can be reduced, so that the shadowing (luminance unevenness) can be reduced and the display quality can be improved.

Further, the first dummy electrode is provided in a portion where a wide space is provided between the terminal groups connected to the TCPs arranged in a line on the end portion of the electrode substrate. , Roughing roller that performs alignment treatment (rubbing) on the alignment film formed on the display electrode, the uneven shape of the part with the terminal and the part without the terminal is transferred, and the rubbing stripe unevenness occurs on the alignment film, and the display quality deteriorates. Can be prevented.
Further, since the first dummy electrode can eliminate the concave portion between the TCPs, the gap between the upper and lower substrates can be made uniform.

Further, since the second dummy electrode is provided in the gap between the plurality of terminals, it is possible to prevent light leakage from the gap between the terminals in the frame portion. Further, the in-plane density of the terminal and the portion where the terminal is directly extended become uniform, and the gap between the upper and lower substrates can be made uniform. In addition, it is possible to prevent the occurrence of uneven shading of the frame portion, which should be originally uniform black, due to the unevenness of the conventional radial straight wiring, and to make the frame portion uniform black. Therefore, the display quality can be improved.

Further, since the first and second dummy electrodes are provided, the gap in the frame portion can be made uniform, so that the color unevenness due to the gap variation in the frame portion does not occur and the display quality is improved. can do.

The above-mentioned JP-A-3-289626,
JP-A-4-70627, JP-A-4-170522,
Japanese Unexamined Patent Publication No. 4-369622 and Japanese Unexamined Patent Publication No. 5-127181 do not describe the idea, configuration, action or effect of the present invention.

[0036]

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

FIG. 11 is an exploded perspective view showing a liquid crystal display module 62 in which a liquid crystal display element 62, a drive circuit for driving the liquid crystal display element 62, and a light source are compactly integrated.

The TCP 10 in which the semiconductor IC chip 34 for driving the liquid crystal display element 62 is mounted has a window portion for fitting the liquid crystal display element 62 in the center, and a frame-shaped body printed with a circuit for driving the liquid crystal. It is mounted on the circuit board 35. Printed circuit board 3 in which liquid crystal display element 62 is fitted
5 is fitted into the window portion of the frame-shaped body 42 formed by plastic molding, the metal frame 41 is overlapped on this, and its claw 43 is bent into the notch 44 formed in the frame-shaped body 42 to form the frame 41. Are fixed to the frame-shaped body 42.

A cold cathode fluorescent tube 36 disposed at the upper and lower ends of the liquid crystal display element 62, a light guide 37 made of an acrylic plate for uniformly irradiating the liquid crystal display cell 60 with light from the cold cathode fluorescent tube 36, A reflecting plate 38 formed by applying white paint to a metal plate and a milky white diffusing plate 39 for diffusing light from the light guide 37 are fitted into the window portion from the back side of the frame-shaped body 42 in the order of FIG. Be done. An inverter power supply circuit (not shown) for lighting the cold cathode fluorescent tube 36 is located at a position (not shown) provided on the right back side of the frame-shaped body 42 so as to face the recess 45 of the reflection plate 38. .). Diffuser 3
9, light guide 37, cold cathode fluorescent tube 36 and reflector 38
Attaches the tongue piece 46 provided on the reflection plate 38 to the frame-shaped body 42.
It is fixed by bending it in the small edge 47 provided in the.

FIG. 12 is a block diagram of a laptop personal computer using the liquid crystal display module 63 for the display section, and FIG. 13 is a diagram showing a state in which the liquid crystal display module 63 is mounted on the laptop personal computer 64. In the laptop personal computer 64, the liquid crystal display module 63 is driven by the liquid crystal driving semiconductor IC chip 34 via the control LSI 48 based on the result calculated by the microprocessor 49.

FIG. 14 is a perspective view of an essential part of the liquid crystal display element 62.

In FIG. 14, the liquid crystal layer 50 is sandwiched between 2
In order to align the liquid crystal molecules between the upper and lower electrode substrates 11 and 12 so as to form a twisted spiral structure, for example, transparent upper and lower electrode substrates 11 and 12 made of glass are in contact with the liquid crystal. For example, a so-called rubbing method is used in which the surfaces of the alignment films 21 and 22 made of an organic polymer resin made of polyimide are rubbed in one direction with, for example, a cloth.
The rubbing direction at this time, that is, the rubbing direction, the rubbing direction 66 in the upper electrode substrate 11, the lower electrode substrate 12
In, the rubbing direction 67 is the alignment direction of the liquid crystal molecules. A gap d is formed so that the rubbing directions 66 and 67 of the two upper and lower electrode substrates 11 and 12 thus oriented may intersect each other at about 180 to 360 degrees.
_The two electrode substrates 11 and 12 are faced with each other so that they face each other, that is, a cutout portion for injecting liquid crystal, that is, a liquid crystal filling port 5
When a nematic liquid crystal having a positive dielectric anisotropy and having a predetermined amount of an optical rotatory substance added thereto is sealed by bonding with a frame-shaped sealing material 52 provided with 1, liquid crystal molecules are separated between the electrode substrates. It has a helical molecular arrangement with a twist angle of θ ₂ . Note 31 and 32 on the respective example a transparent consisting of indium oxide or ITO, a lower electrode (lower electrode 32 corresponds to 2 ₁ to 2 ₈ in FIG. 1). A member for producing a birefringence effect on the upper electrode substrate 11 of the liquid crystal cell 60 thus configured (hereinafter referred to as a birefringence member. Fujimura et al. "STN-LCD retardation film", magazine electronic material 1
40, February 991 issue, pages 37-41), and further upper and lower polarizing plates 15 and 16 sandwiching the member 40 and the liquid crystal cell 60.

The twist angle θ ₂ of the liquid crystal molecules in the liquid crystal 50
Can take a value in the range of 180 to 360 degrees, but is preferably 200 to 300 degrees, but the phenomenon that the lighting state in the vicinity of the threshold value of the transmittance-applied voltage curve becomes a light scattering orientation From the practical viewpoint of avoiding and maintaining excellent time division characteristics, the range of 230 degrees to 270 degrees is more preferable. This condition basically makes the response of the liquid crystal molecules to the voltage more sensitive and acts to realize excellent time division characteristics. Further, in order to obtain excellent display quality, the product Δ of the refractive index anisotropy Δn ₁ of the liquid crystal layer 50 and its thickness d ₁
It is desirable that n ₁ · d ₁ is set in the range of preferably 0.5 μm to 1.0 μm, more preferably 0.6 μm to 0.9 μm.

The birefringent member 40 acts so as to modulate the polarization state of the light passing through the liquid crystal cell 60, and converts the liquid crystal cell 60 alone, which was capable of only colored display, into black and white display. Thus the birefringent member 40 refractive index anisotropy [Delta] n ₂ and is extremely important product [Delta] n ₂ · d ₂ of a thickness d _2, preferably 0.8μm from 0.4 .mu.m, more preferably 0.5μm To 0.7 μm.

Further, since the liquid crystal display element 62 utilizes elliptically polarized light due to birefringence, the axes of the polarizing plates 15 and 16 and the optical axis of the uniaxial transparent birefringent plate when the birefringent member 40 is used. And the electrode substrate 11 of the liquid crystal cell 60,
The relationship between the liquid crystal alignment directions 12 and 6 is extremely important.

FIG. 15 is a partially cutaway perspective view of an example of the upper electrode substrate portion of a liquid crystal display element having a color filter.

As shown in FIG. 15, red, green, and blue color filters 33R, 33G, 33B, on the upper electrode substrate 11,
By providing the light shielding film 33D between the filters, multicolor display is possible.

In FIG. 15, each filter 33
On the R, 33G, 33B and the light shielding film 33D, a smoothing layer 23 made of an insulating material is formed in order to reduce the influence of these irregularities, and then an upper electrode 31 and an alignment film 21 are formed.

Example 1 FIG. 1 is a partial plan view of an electrode substrate which constitutes a liquid crystal display element of Example 1 of the present invention. One TC mounted on the electrode substrate manufactured by the optimum algorithm according to the present invention.
FIG. 9 is a schematic plan view showing a part of the lead wiring on the right side of the center line of the terminal group corresponding to P. In addition, 1 which is a driving element
The number of electrodes of each TCP (tape carrier package) is
Usually, there are about 80 to 160 lines, but in the embodiment, it is omitted in the drawing. Even if the number is different, the structure of the lead wiring according to the present invention can be applied as it is. Further, FIG. 7A shows a plan view of a range approximately four times as large as that in FIG.

Reference numeral 12 denotes a liquid crystal display element (not shown here).
11, the electrode substrate made of an insulating substrate made of one transparent glass constituting the reference numeral 62 reference) in FIG. 14, 2 ₁ ~
2 ₈ is formed on the surface of the electrode substrate 12, a transparent conductive film, in parallel lines, the display electrodes constituting the pixel (FIG. 8, shown in FIG. 14, reference numeral 32), 3 ₁ to 3 ₈ TCP
(Not shown here. See reference numeral 10 in FIGS. 10 and 11)
Terminals (connecting electrodes, that is, input terminals) connected to the electrodes (the output-side outer leads) of the terminals ₁₁ to ₁₈ are parts of the terminal lead-out wiring connecting the display electrodes 2 and the terminals 3. Straight wiring, 71 is TCP for this electrode substrate 12
A TCP alignment mark for mounting on top, 72 is a center line of a terminal group corresponding to one TCP mounted on the electrode substrate 12, and 52 is a portion where a sealing material is provided.

The pitch of the plurality of display electrodes 2 which are wired in parallel on the electrode substrate 12 is larger than the pitch of the electrode substrate 12.
The pitch of the terminals 3 of each display electrode 2 connected to the TCP, which is drawn to the end of the, is narrower, and therefore the lead wiring 1 for connecting the two is required. The lead wiring is
The two extended portions are connected to each other by extending the display electrode 2 and the terminal 3 as they are, and the angles θ with respect to the display electrode 2 and the terminal 3 are equal to each other, that is, they are slanted in parallel. The length of the two extended portions and the width of the diagonal linear wiring 1 are calculated and formed so that the wiring resistances of the linear wiring 1 are equal to each other.

There are the following four basic conditions for wiring.

All the diagonal straight lines 1 are parallel lines with an angle θ (-θ on the left side of the center line 72). Center line 72
It is line symmetric with respect to. The angle θ is, for example, 25 to 50 °
Is.

All the distances between the diagonal straight lines 1 are set to the wiring rule d _LCD . I can't afford it.

The terminal 3 has the same width over the entire length including the extension. The terminal 3 and the display electrode 2 are parallel (perpendicular to the terminal lead-out end portion of the electrode substrate 12 of the liquid crystal display element). The distance between the terminals 3 is the TCP crimping rule d.
_TCP .

The display electrode 2 has the same width over the entire length including the extension. The distance between the display electrodes 2 is TCP pressure bonding rule d _LCD .

Hereinafter, the structure of the lead wiring 1 will be described in detail with reference to FIGS. 2 and 3.

The wiring algorithm is as follows.

(1) First, the first lead wiring on the right side of the center line 72 connects the display electrode 2 ₁ and the terminal 3 _{1 as} they are (see FIG. 2).

(2) A line with an arbitrary angle θ is drawn starting from the end C ₁ of the display electrode 2 ₁ .

(3) Extension line of angle θ from C ₁ and terminal 3
Let B ₁ be the intersection with the extension line of.

(4) Extension line of terminal 3 ₂ and line segment B ₁ -C ₁
A ₂ is calculated so that the distance from the distance is d _LCD .

(5) A line with an angle θ (a line parallel to the line segment B ₁ -C ₁ ) is drawn from A ₂ as a starting point, and the intersection with the extension line with the display electrode 2 ₂ is D ₂ .

[0064] (6) arbitrarily determine the width w ₁ of the diagonal straight line wiring 1 _1.

(7) A line (parallel to the line segment A ₂ -D ₂ ) having a distance of w _{2 from the} line segment A ₂ -D ₂ is drawn, and the line and the terminal 3 ₂
Let B ₂ be the intersection with the extension line of C, and C ₂ be the intersection with the extension of the display electrode 2 ₂ .

(8) The middle point of the line segment A ₁ -B ₁ is E ₁ , and the line segment D ₁
-C ₁ midpoint is F ₁ , line segment A ₂ -B ₂ midpoint is E ₂ , line segment D ₂
The midpoint of -C ₂ and F _2, the distance on the y-axis between the E ₁ and E ₂ l
₁ , the length of the line segment E ₁ -F ₁ is m ₁ , the length of the line segment E ₂ -F ₂ is m ₂ , and the y-axis component of F ₂ is P ₂ .

(9) To satisfy the following calculation formula,
The width w ₂ of the diagonal straight wiring 1 ₂ of the lead wiring is obtained. That is, w ₂ is determined under the condition that the wiring resistances of the first and second lead wires are equal. W _TCP is the width of the terminal 3 determined corresponding to the width of the TCP electrode, W _LCD is the width of the display electrode 2, and R _sq is the sheet resistance (Ω) of the electrode wiring material.
/ □).

[0068]

[Equation 1]

(10) Let B ₂ and C ₂ which are determined by w ₂ obtained by the above calculation formula be the final coordinates.

(11) With the above, the first and second lead wirings are determined.

(12) Next, in determining the third lead wiring, the same procedure as (2) to (10) above may be performed. However, the calculation formula for determining the width w ₃ of the oblique straight line 1 _3, using the following formula.

[0072]

[Equation 2]

(13) After that, this process is repeated until the nth lead wiring is sequentially obtained. Width w _n of the diagonal straight line wiring 1 _n
To find, use the following formula:

[0074]

(Equation 3)

(14) When the coordinates A _n , B _n , E _n , and D _n to the last n-th lead-out wiring are determined, the wiring resistance R of the n-th lead-out wiring is obtained from the following calculation formula.

[0076]

[Equation 4]

(15) Coordinate B _{n of the n-th} lead wire
Determines the y-axis height of the entire diagonal linear wiring pattern. That is, in the first to n-1th lead wirings, the terminals 3 _{1 to} 3 _n-1 are extended according to B _n . Then, the wiring resistances of the first to n-th lead wirings are all equal to R.

(16) Finally, a numerical calculation is performed using the angle θ as a variable to obtain the angle θ that minimizes the wiring resistance R.
Coordinates A of the first to nth lead wires at this time
_{1, B 1, E 1,} D 1 ~A n, B n, E n, which graphically up D _n.

The coordinates A _{1 of the first} lead wire,
B ₁ , E ₁ , and D ₁ are obtained by the following calculation formula.

[0080]

(Equation 5)

Further, the coordinates A _{1 of the first} lead wire,
Detailed calculation formulas of B ₁ , E ₁ , and D ₁ are shown below.

[0082]

(Equation 6)

Further, the coordinates A _{2 of the second} lead wiring,
B ₂ , E ₂ , and D ₂ are calculated by the following formulas.

[0084]

(Equation 7)

Also, the coordinates A _{2 of the second} lead wiring,
Detailed formulas for calculating B ₂ , E ₂ , and D ₂ are shown below.

[0086]

[Equation 8]

Further, the coordinates A _{n of the nth} lead wiring,
B _n , E _n , and D _n are obtained by the following calculation formula.

[0088]

[Equation 9]

Further, the coordinates A _{n of the nth} lead wiring,
Detailed calculation formulas of B _n , E _n , and D _n are shown below.

[0090]

[Equation 10]

In the lead-out wiring formed as described above, since the area utilization efficiency (wiring efficiency) of the lead-out wiring can be improved, the length of the lead-out wiring can be shortened. Therefore, it is conventionally 500 to 1 kΩ. The wiring resistance can be reduced by 30 to 40%. Further, since the reduction can be provided as a margin of the on-resistance of the driving semiconductor IC chip, the size of the semiconductor IC chip can be reduced. Further, since the length of the lead-out wiring can be made shorter than in the conventional case, the size of the liquid crystal display element can be reduced. As a result, the manufacturing cost can be reduced. Further, since the wiring resistance is reduced, the distortion of the waveform driving the liquid crystal and the distortion of the crosstalk can be reduced, so that the shadowing (luminance unevenness) can be reduced and the display quality can be improved.

Embodiment 2 FIG. 4 is a plan view of a main portion of a lead wiring portion of an electrode substrate according to Embodiment 2 of the present invention. Note that FIG. 7B shows a plan view of a range approximately four times as large as that in FIG.

In the present embodiment, in addition to the structure of the first embodiment, a plurality of TCPs (see reference numeral 10 in FIGS. 10 and 11) are arranged in a line on the end portion of the electrode substrate 12. A dummy electrode 4 is provided in a space between the terminal groups 3 corresponding to the connecting terminal group 3 (see reference numeral 30 in FIG. 7B).
The dummy electrode 4 has a shape as shown in the figure that fills the space, that is, a parallel electrode 4a having the same pitch and the same width as the terminal 3, and an oblique linear electrode 4b. The diagonal linear electrodes 4b are provided between the diagonal linear wirings 1 of the outermost adjacent terminals 3 of the group of terminals 3 at the same angle and the same pitch as the diagonal linear wirings 1. In this embodiment, the dummy electrode 4 is made of an ITO film,
It is electrically floating.

Conventionally, there is a space between a plurality of TCPs and a group of terminals 3 connected to each other.
Due to the thickness of the terminal 3 made of a thick ITO film of 2 to 0.3 μm, there is a height difference between the portion with the terminal 3 and the portion without the terminal 3 and is formed on the display electrode 2 during mass production of the liquid crystal display element. This shape is transferred to a rubbing roller that performs an alignment process (rubbing) on the alignment film, and if the alignment process is performed using this rubbing roller, uneven rubbing stripes are generated in the alignment film, which causes a problem that display quality deteriorates. However, in this embodiment, by filling the space between the TCPs (between the groups of terminals 3) with the dummy electrodes 4, it is possible to make the space have the same unevenness condition on both sides, that is, the rubbing condition. As described above, the rubbing line unevenness does not occur in the alignment film, and the display quality can be improved. Further, by providing the dummy electrode 4 in the space between TCPs, TCP
Since the recess of about 0.2 μm can be eliminated, the gap between the upper and lower substrates can be made uniform. Therefore, it is possible to realize a uniform black non-lighting area without uneven density unevenness in the frame portion, and it is possible to satisfactorily control the gap between both substrates, so that color unevenness is prevented. Since it can be prevented, the display quality can be improved.

Embodiment 3 FIG. 5 is a plan view of a main portion of a lead wiring portion of an electrode substrate according to Embodiment 3 of the present invention. Note that FIG. 7C shows a plan view of a range approximately four times as large as that in FIG.

In this embodiment, in addition to the constitutions of the first and second embodiments, as shown in FIG. 5, the upper and lower electrode substrates are provided inside the sealing material 52 of the completed liquid crystal display element (on the side where the liquid crystal is interposed). A dummy electrode 5 is provided in a space between the terminals 3 in a so-called frame portion which is a non-lighting portion outside the display portion (lighting portion) where the respective electrodes intersect. In addition,
The pitch of the dummy electrodes 5 is the same, and the distance between the dummy electrodes 5 and the terminals 3 on both sides thereof (the length of the distance between the two) is the same, and in the present embodiment, it is the same as the distance between the adjacent diagonal linear wirings 1. . Further, in this embodiment, the dummy electrode 5 is made of an ITO film and is electrically floating.

In the present embodiment, since the dummy electrode 5 is provided in the gap between the terminals 3 in the portion including the frame portion, it is possible to prevent light leakage from the gap between the terminals 3 in the frame portion. . Further, the in-plane density of the terminal 3 and a portion where the terminal 3 is directly extended becomes uniform, and the gap between the upper and lower substrates can be made uniform. Conventionally, as shown in FIG. 16, since the diagonal linear wiring 1 of the lead-out wiring is radial, the interval between the diagonal linear wiring 1 is from the display electrode 2 to the terminal 3.
As a result, there is a problem in that the unevenness that becomes narrower toward the direction occurs, and as a result, uneven unevenness in density occurs at a portion of the frame portion where the original black should be uniform. Since the electrodes 4 and 5 are provided, the gap in the frame can be made uniform, which solves this problem.
The frame portion can be made uniform black, and the display quality can be improved. Further, in the conventional liquid crystal display element, since the display electrodes 2 and the diagonal linear wirings 1 made of the ITO film having a thickness of 0.2 to 0.3 μm of the upper and lower electrode substrates support the spacers, the spacers where there are no electrodes are free. However, there is a problem that the gap control is not effective and the conventional radial diagonal straight line wiring 1 does not have a uniform wiring density as described above, so that color unevenness due to the gap variation in the frame portion occurs. In particular, in STN-LCDs that require a highly accurate gap (± 0.1 μm) between both electrode substrates, the effective density in which the spacers for providing the gap are significantly affected. In the present embodiment, since the dummy electrodes 4 and 5 are provided, the gap in the frame portion can be made uniform, so that this problem is solved, color unevenness due to the gap variation in the frame portion does not occur, and display quality is improved. Can be improved.

In the present embodiment, the dummy electrode 5 is electrically floating, but as shown in FIG. 6, for example, the connecting portion of the minimum pattern is formed so that the wiring resistance of the lead wiring becomes the same as that of the other lead wiring. 5'may be connected at one point.

Example 4 FIG. 8 shows an example in which an electrode including a lead wire and a dummy electrode of Example 3 of the present invention was applied to an upper electrode substrate and a lower electrode substrate, and both substrates were superposed and assembled. FIG. 9 is a schematic plan view showing an upper electrode and a lower electrode provided with an electrode pattern duplicated in Example 3 so that dummy electrodes having the same shape face each other.

In this way, of the two electrode substrates 11 and 12, the terminals, the lead wires and the dummy electrodes formed at the end portions of one of the electrode substrates 11 and 12 are connected to the other electrode substrate 12,
The two electrode substrates 1 are formed on the opposite surfaces of the substrate 11.
Since the gap between 1 and 12 can be made uniform,
The frame portion can be made uniform black, and color unevenness due to the gap variation of the frame portion does not occur, so that the display quality can be improved.

FIGS. 9A to 9C are a plan view of a main part of a liquid crystal display device to which the present invention is applicable and a cross-sectional view of the corresponding main part.

Reference numeral 15 is an upper polarizing plate, 73 is a retardation plate, 11 is an upper electrode substrate, 31 is an upper electrode, 74 is an insulating film, 21 is an upper alignment film, 50 is a liquid crystal layer, 75 is a spacer, and 22 is a lower alignment. A film, 32 is a lower electrode, 76 is a flattening film, 33 is a color filter, 33D is a black matrix, 12 is a lower electrode substrate, and 16 is a lower polarizing plate.

FIG. 10 is a plan view showing a connection state of a liquid crystal display device to which the present invention is applied, with a printed circuit board, a TCP on which a drive LSI chip is mounted, and a liquid crystal display element.

Although the present invention has been specifically described based on the embodiments, the present invention is not limited to the above embodiments, and various modifications can be made without departing from the scope of the invention. . For example, in the above-described embodiment, an example in which the present invention is applied to a simple matrix type liquid crystal display device is shown, but the present invention is not limited to this, and it is also applicable to an active matrix type liquid crystal display device using thin film transistors and the like as switching elements. Needless to say.
When applied to an active matrix type liquid crystal display element, the display electrode of FIG. 1 is a scan signal line (that is, a gate signal line or a horizontal signal line) or a video signal line (on a substrate on which a switching element is provided). That is, the drain signal line or the vertical signal line).

[0105]

As described above, according to the present invention,
It is possible to provide a liquid crystal display device that has a high efficiency of area utilization of lead wires and has a short lead wire with low resistance. In addition, there is no rubbing stripe unevenness in the display portion, there is no uneven density unevenness in the frame portion, there is a uniform black non-lighting area, and the gap between both substrates can be controlled well, It is possible to provide a liquid crystal display device in which color unevenness does not occur.

[Brief description of drawings]

FIG. 1 is a partial plan view of an electrode substrate showing a lead wire of a first embodiment of a liquid crystal display device of the present invention.

FIG. 2 is a detailed explanatory diagram for calculating the coordinates of the first and second lead wirings according to the first embodiment of the present invention.

FIG. 3 is a detailed explanatory diagram for calculating the coordinates of the (n−1) th and nth lead wirings according to the first embodiment of the present invention.

FIG. 4 is a partial plan view of an electrode substrate in which a dummy electrode is provided in a gap between terminal groups according to the second embodiment of the liquid crystal display device of the present invention.

FIG. 5 is a partial plan view of an electrode substrate in which a dummy electrode is further provided in a gap between terminals according to the third embodiment of the liquid crystal display device of the present invention.

FIG. 6 is a partial plan view of FIG. 5 showing an embodiment in which a dummy electrode and lead wiring are electrically connected.

7 (A) to (C) are the same as in Examples 1 to 3, respectively.
FIG. 4 is a partial plan view of the electrode substrate showing a lead-out wiring portion in a wide range of about 4 times.

FIG. 8 is a diagram showing the third embodiment of the present invention, in which electrodes including lead wires and dummy electrodes are applied to an upper electrode substrate and a lower electrode substrate, both substrates are superposed and assembled, and then the same shape is obtained. FIG. 8 is a schematic plan view showing an upper electrode and a lower electrode provided with an electrode pattern duplicated in the third embodiment so that the dummy electrodes of FIG.

9A to 9C are a plan view of a main part of a liquid crystal display device to which the present invention is applicable and a cross-sectional view of the corresponding main part.

FIG. 10 is a view showing a liquid crystal display device to which the present invention can be applied, a printed circuit board, a TCP on which a drive LSI chip is mounted,
FIG. 3 is a plan view showing a connection state with a liquid crystal display element.

FIG. 11 is an exploded perspective view of an example of a liquid crystal display module to which the present invention can be applied.

12 is a block diagram of an example of a laptop personal computer in which the liquid crystal display module of FIG. 11 is mounted as a display unit.

13 is a perspective view of an example of the laptop computer of FIG.

FIG. 14 is an exploded perspective view of a main part of an example of a liquid crystal display element.

FIG. 15 is a partially cutaway perspective view of an example of an upper electrode substrate portion of a liquid crystal display element.

FIG. 16 is a partial plan view showing a lead wire of a conventional liquid crystal display device.

[Explanation of symbols]

1 ₁ to 1 ₈ ... oblique straight line, 2 ₁ to 2 ₈ ... display electrode, 3 ₁
~ 3 ₈ ... Terminal, 12 ... Electrode substrate, 52 ... Sealing material, 71
... TCP alignment mark, 72 ... center line of terminal group corresponding to one TCP.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Tomohide Ohira 3300 Hayano, Mobara-shi, Chiba Hitachi, Ltd. Electronic Device Division (72) Inventor Tatsunori Fumikura 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd. (72) Inventor Hitomi Hitomi 3681 Hayano, Mobara-shi, Chiba Hitachi Device Engineering Co., Ltd.

Claims (13)

[Claims] 1. A plurality of electrodes, each of which is wired in parallel on a substrate, and a terminal of each electrode, which is drawn out to an end portion of the substrate and connected to a driving element, In a liquid crystal display device including a liquid crystal display element having a pitch and a pitch of the terminals different from each other and having lead wires connecting the electrodes and the terminals, the lead wires are directly extended from the electrodes. And the part
The portion extended from the terminal as it is and the two extended portions are connected to each other, and each of them is composed of diagonal straight wirings which are substantially parallel to each other, and the wiring resistances of the lead wirings are substantially equal to each other. A liquid crystal display device, which is formed by adjusting the lengths of two extended portions and the width of the diagonal linear wiring. 2. A plurality of electrodes wired in parallel on an insulating substrate, and a terminal of each electrode that is drawn out to an end of the insulating substrate and connected to a driving element,
In the liquid crystal display device including the liquid crystal display element in which the pitch of the terminals is smaller than the pitch of the electrodes, and the diagonal linear wiring that connects the electrodes and the terminals is provided, the liquid crystal display device is directly connected to the electrodes. An extended portion and a portion directly extended from the terminal are connected by the diagonal linear wirings having substantially the same angle with respect to the electrode or the terminal, and a wiring resistance including the two extended portions and the diagonal linear wiring. The liquid crystal display device is characterized in that the lengths of the two extended portions and the width of the diagonal straight line are calculated and formed so that the two are substantially equal to each other. 3. The liquid crystal display device according to claim 1, wherein the lengths of the intervals between the portions which are directly extended from the adjacent electrodes are substantially equal to each other. 4. The liquid crystal display device according to claim 1, wherein the lengths of the intervals between the adjacent diagonal linear wirings are substantially equal to each other. 5. A plurality of the driving elements connected to the terminals are mounted side by side on the substrate, and a terminal group composed of the plurality of terminals connected to each driving element is a group of the terminals. 3. The liquid crystal according to claim 1, wherein a first dummy electrode is formed on the substrate with a second spacing wider than the first spacing, and the second dummy spacing is formed on the substrate. Display device. 6. The first dummy electrode includes at least one dummy parallel electrode formed at substantially the same pitch and substantially the same width as the terminal and substantially in parallel with the terminal. Item 5. The liquid crystal display device according to item 5. 7. The first dummy electrode includes a dummy diagonal linear electrode substantially parallel to the diagonal linear wiring formed between the outermost diagonal linear wirings of the adjacent terminal groups. The liquid crystal display device according to claim 5. 8. A plurality of dummy parallel electrodes, wherein the first dummy electrodes have a pitch and a width substantially equal to those of the terminals, and are formed substantially parallel to the terminals, and the first dummy electrode is the most adjacent one of the terminal groups. 6. The liquid crystal display device according to claim 5, comprising at least two dummy diagonal linear electrodes that are substantially parallel to the diagonal linear wirings on both sides formed between the diagonal linear wirings on the outside. 9. The liquid crystal display device according to claim 1, wherein a second dummy electrode is formed between the adjacent terminal or a portion directly extended from the terminal. 10. The liquid crystal display device according to claim 9, wherein the second dummy electrode and the terminals on both sides of the second dummy electrode or portions directly extended from the terminals have substantially equal intervals. 11. The second dummy electrode and the terminals on both sides of the second dummy electrode or portions directly extended from the terminal have substantially equal intervals, and the intervals have a length that is adjacent to each other. 10. The liquid crystal display device according to claim 9, wherein the length of the interval between the straight lines is substantially equal. 12. The liquid crystal display device according to claim 5, wherein the first and second dummy electrodes include at least one material layer which is the same as the terminal. 13. Of the two substrates, at least a part of the terminals, the lead wires, and the dummy electrodes formed at the end of one of the substrates is formed on the opposite surface of the other substrate. The liquid crystal display device according to claim 1, 2, 5, or 9.