JPH023020A - Liquid crystal display and its manufacture - Google Patents

Abstract

PURPOSE:To obtain a liquid crystal display whose display performance is high and whose cost is low by providing an accumulation capacity being larger than a capacitance of a liquid crystal placed between a scanning electrode ad a signal electrode, in parallel to the capacitance of the liquid crystal. CONSTITUTION:In a liquid crystal display formed by inserting and holding, and opposing and fixing a first substrate consisting of row-like scanning electrodes 2 and a second substrate consisting of line-like signal electrode 1, and injecting a liquid crystal into between these substrates, an accumulation capacity 4 being larger than a capacitance 3 of a liquid crystal placed between the scanning electrode 2 and the signal electrode 1 is provided in parallel to the capacitance 3 of the liquid crystal. Subsequently, the first substrate and the second substrate are inserted and held, and opposed and fixed, and also, a terminal part of the scanning electrode 2 of the first substrate and a terminal part of the signal electrode 1 of the second substrate are connected electrically by anisotropic conductive film. Accordingly, the accumulation capacity 4 being larger than the liquid crystal capacity 3 can be provided. In such a way, a high display performance being equal to an active matrix is obtained, and the display can be suppressed to a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a liquid crystal display, and particularly to a matrix type liquid crystal display that can display a large amount of information.

(: Prior Art) In a conventional matrix liquid crystal display, as shown in the schematic diagram of a conventional simple matrix liquid crystal display in FIG. was used to retain charge and change the optical properties of the liquid crystal itself.

[Problem to be solved by the invention]

The conventional simple matrix type liquid crystal display mentioned above uses the electrically imperfect capacitance of the liquid crystal itself to hold charge, so the disadvantage is that the contrast between the selected point and the half-selected point decreases as the display capacity increases. there were.

In order to prevent the deterioration in display quality as described above, various active matrix liquid crystal displays have been manufactured. An example of an active matrix liquid crystal display using thin film transistors will be described with reference to FIG. 7, a schematic diagram showing an active matrix liquid crystal display. This is because the thin film transistor 12 is used, so when the scanning electrode 2 is selected, a voltage is applied between the signal electrode 1 and the common electrode 13 and the voltage is applied to the capacitor 3 of the liquid crystal, but when the scanning electrode 2 is not selected, a voltage is applied between the signal electrode 1 and the common electrode 13. Since the voltage applied to the signal electrode 1 does not affect the capacitance 3 of the liquid crystal, the operation is the same as static operation even if the capacitance 3 of the liquid crystal is electrically incomplete. Therefore, there is almost no decrease in contrast, and a liquid crystal display with high display quality can be manufactured.

However, since the manufacturing process of active matrix liquid crystal displays is complicated, they have a serious drawback of being expensive.

[Means to solve the problem]

In the liquid crystal display according to the present invention, a first substrate consisting of column-shaped scanning electrodes and a second substrate consisting of row-shaped signal electrodes are sandwiched and fixed to face each other. In a liquid crystal display in which liquid crystal is injected between scanning electrodes and signal electrodes, a storage capacitance larger than the capacitance of the liquid crystal sandwiched between the scanning electrode and the signal electrode is provided in parallel with the capacitance of the liquid crystal.

The method for manufacturing a liquid crystal display of the present invention includes a step of forming signal electrodes in rows on a transparent insulating substrate, a step of forming an insulating film except for the terminal portion of the signal electrodes, and a step of forming signal electrodes in rows on the insulating film. A step of forming a scanning electrode to form a first substrate, and fixing the first substrate by sandwiching it to face a second substrate on which a row of signal electrodes are formed, and also fixing the terminal portion of the signal electrode of the first substrate. and electrically connecting terminal portions of the signal electrodes of the second substrate with an anisotropic conductive film.

Furthermore, the method for manufacturing a liquid crystal display of the present invention includes a step of forming signal electrodes in rows on a transparent plastic substrate, a step of forming an insulating film covering half of the signal electrodes in the row direction, and a step of forming rows of signal electrodes on the insulating film. The method includes at least a step of forming scan electrodes, and a step of bending the transparent plastic substrate perpendicular to the direction of the row signal electrodes and sandwiching and fixing the row signal electrodes and the column scan electrodes so that they face each other.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is a schematic diagram showing an embodiment of a liquid crystal display according to the present invention, and FIG. 4 is a schematic diagram showing a cross section of a liquid crystal display manufactured by the method for manufacturing a liquid crystal display according to the present invention. A transparent conductive film of 0.1 μm is formed on the first substrate 5 and the second substrate 7 by argon sputtering, and then the signal electrodes 1 are formed in rows by using the photoresist method. Next, silicon dioxide was formed to a thickness of 0.5 μm by argon sputtering as an insulating film 6 except for the terminal portions of the first substrate, and then transparent grooves tli of 0.1 μm were formed by argon sputtering, and a row pattern was formed using a photoresist method. A scanning electrode 2 was formed. After the first substrate 5 and the second substrate 7 are subjected to alignment treatment, the first substrate 5 and the second substrate 7 are sandwiched and fixed facing each other with a gap of 10 μm using a sealing material 8, and an anisotropic conductive film is applied. 10 to electrically connect the first substrate 5 and the second substrate 7, liquid crystal was injected to form a liquid crystal display. The display area was 160 mm x 192 mm, and the display pixels were 400 x 640 reflective monochrome displays for office automation. The storage capacity 4 was about 10 times the liquid crystal capacity 3.

The liquid crystal display manufactured in this manner had a contrast of 20:1 or more, and exhibited display performance equivalent to that of an active matrix. Also, although the process is slightly more involved than with a simple matrix, the price can be kept at the same level as that of a liquid crystal display.

Although not used in this embodiment, it is also possible to construct a storage capacitor 4 larger than the liquid crystal capacitor 3 in parallel with the liquid crystal capacitor 3 as shown in FIGS. 2 and 3, which are schematic diagrams showing application examples of this embodiment. Needless to say, the same effects as those of the example are shown.

FIG. 5 is a schematic diagram showing a cross section of a liquid crystal display manufactured by another method for manufacturing a liquid crystal display according to the present invention.

A transparent conductive film of 0.1 .mu.m was formed using a polyester film as a transparent plastic substrate 11 by argon sputtering, and then linear signal electrodes 1 were formed by using a photoresist method. Next, 0.00% silicon dioxide was deposited by argon sputtering to form an insulating film 6 covering half of the row signal electrodes.
A transparent conductive electrode of 0.1 μm was formed on the 5 μm-thick conductive electrode by argon sputtering, and a column-shaped scanning electrode 2 was formed by using a photoresist method. The transparent plastic substrate 11 is aligned at right angles to the direction of the trailing signal electrodes, and the row signal electrodes 1 and the column scanning electrodes 2 are sandwiched and opposed to each other with a sealing material 8 at an interval of 10 μm. After fixing it, liquid crystal was injected to form a liquid crystal display. A card-type display with a display area of 48 mm x 48 mm and a display pixel count of 240 x 240 was used.

The storage capacity 4 was about 10 times the liquid crystal capacity 3. The liquid crystal display manufactured in this way has a contrast of 15:
1 or higher, indicating good display performance. The total cost was almost the same as the simple matrix. Note that since there is currently no example of forming a thin film transistor on a plastic substrate, a contrast ratio of 15:1 or more was obtained.

〔Effect of the invention〕

As explained above, since the present invention has a storage capacitor 4 larger than the liquid crystal capacitor 3 in parallel with the liquid crystal capacitor 3, it has a higher capacity than the electrically imperfect capacitance of the liquid crystal itself like a conventional simple matrix type liquid crystal display. Excellent display properties such as contrast. Furthermore, since the number of steps is smaller than in the manufacturing method of an active type liquid crystal display, it is possible to provide a liquid crystal display with high display performance and low cost.

Claims (1)

[Claims] 1. A first substrate consisting of rows of scanning electrodes and a second substrate consisting of rows of signal electrodes are sandwiched and fixed to face each other, and the first substrate and the second substrate are sandwiched and fixed to face each other. In a liquid crystal display in which a liquid crystal is injected between the scanning electrode and the signal electrode, a storage capacitance larger than the capacitance of the liquid crystal sandwiched between the scanning electrode and the signal electrode is provided in parallel with the capacitance of the liquid crystal. Features a liquid crystal display. 2. forming rows of signal electrodes on a transparent insulating substrate; forming an insulating film except for the terminal portions of the signal electrodes; forming rows of scanning electrodes on the insulating film; forming a substrate; the first substrate and a second substrate on which rows of signal electrodes are formed are sandwiched and fixed so as to face each other, and the terminal portions of the signal electrodes of the first substrate and the second substrate are 1. A method for manufacturing a liquid crystal display, comprising at least the step of electrically connecting a terminal portion of a signal electrode with an anisotropically conductive film. 3. Forming row-shaped signal electrodes on a transparent plastic substrate, forming an insulating film covering half of the row-shaped signal electrodes in the direction, and forming column-shaped scanning electrodes on the insulating film. manufacturing a liquid crystal display, comprising at least the step of bending a transparent plastic substrate at right angles to the direction of the row signal electrodes, and sandwiching and fixing the row signal electrodes and the column scan electrodes so that they face each other. Method.