JPS5817482A - Liquid crystal display - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid crystal display device in which comb-shaped electrodes are provided on both substrates that sandwich a liquid crystal. In a liquid crystal display device in which a liquid crystal is sealed between the transparent electrodes, it has been proposed that the transparent electrodes are composed of comb-shaped electrodes arranged facing each other on the same plane so that the toothed portions interlock with each other.

This is because the electric field generated by the interlocking comb-like electrodes changes the alignment direction of liquid crystal molecules near the substrate.Since the liquid crystal molecules are rearranged only by rotation of the molecules in one plane, two This method has the advantage of shortening the response time compared to the conventional NT method which requires rotation of stages.

In addition, when interdigitated electrodes are used, separate displays can be performed depending on the arrangement of the electrodes on each substrate, so the orientation of liquid crystal molecules can be changed using electrodes that are placed opposite each other with the conventional liquid crystal layer sandwiched in between. It is possible to double the display function compared to the previous model.

However, when double-sided display is performed in this way, the number of terminals increases dramatically.

Therefore, as the number of LSI terminals increases, the L8I cost increases, and the number of bonding steps also increases, resulting in a significant increase in total cost. In order to prevent this, it is necessary to reduce the number of terminals by changing the driving method to a time division method, but in this case, unlike the case of static driving in which each display pattern has 1ill of segment electrodes, two or more A common segment electrode must be used in the pattern, and an opposing common electrode must be formed on the same substrate surface. As a result, the lead-out portions of the segment electrodes and the common electrode cross each other on the same substrate, making wiring impossible.

The present invention has been made in view of the above circumstances, and its object is to provide a liquid crystal display device in which pairs of interdigitated electrodes are provided on peripheral substrates sandwiching a liquid crystal layer, using each pair of electrodes. An object of the present invention is to provide a liquid crystal display device that can perform separate displays by time-division driving.

In order to achieve such an object, the liquid crystal display device according to the present invention provides a connecting portion made of a conductor between the circumferential substrates to connect the two, and a connecting portion of a part of the interdigital electrodes facing each other on one substrate is provided. A part of the is pulled out onto the opposing board via the connection part,
The comb-shaped electrodes are intersected with the other comb-shaped electrode on the one substrate. Hereinafter, the liquid crystal display device according to the present invention will be explained in detail using Examples.

FIG. 1 is a front view showing a display example in an embodiment of a liquid crystal display device according to the present invention. In the figure, an upper plate 1 and a lower plate 2 have their peripheral parts sealed with a sealing material 3, and a liquid crystal layer is sealed between them.

The inside of the sealing material 3 is an effective display area, and display sections 4 and 5 are provided on the upper plate side and the lower plate side, respectively. That is, in this case, the upper plate side displays the hour and 9 minutes, and the lower plate side displays the hour and minute mark. Both display sections 4 and 5 are each composed of a pair of comb-shaped electrodes.

When performing such a display, static drive requires a total of 24 terminals (23 segment terminals and 1 common terminal) on the upper plate side, and a total of 32 terminals (31 segment terminals and 1 common terminal) on the lower plate side. , resulting in a large number of 56 pieces in total.

Therefore, in this embodiment, in order to perform time-division driving, the connections as shown in FIGS. 2 and 3 are used.

That is, as shown in FIG. 2, on the upper plate side, there are a common terminal 6.7 for the upper plate side common electrode, a common terminal 8.9 for the lower plate side common electrode, and a terminal 10 for the upper plate side segment electrode.
Terminals 11 for segment electrodes on the lower plate side are arranged together at the periphery. Here, the common electrode 12 (indicated by a broken line in the figure) and the segment electrode 13 (indicated by a solid line in the figure) that constitute the display section 4 on the upper panel side are formed on the same substrate, so they are mutually connected. The common terminal 6 without crossing
, 7 and terminal 10 respectively. Therefore, as shown in FIGS. 2 and 3, most of the 1-segment electrode 130 is first pulled out to the lower plate side via the connecting portion 14 (indicated by ■ in the figure) provided at the periphery and extended. After 7't (13m), l! Other connections in the peripheral part 15
(indicated by ■ in the figure), return to the upper plate side (13 m), and connect to the terminal 10 from there. On the other hand, the common electrode 12 on the upper plate side has the connecting portions 14 and 15 at the outer periphery of the upper plate.
and the common terminal 6. It is connected to T. Therefore, the segment electrode 13 straddles the common electrode on the upper plate side between the connecting parts 14 and 15 on the lower plate side.

Similarly, in order to avoid the common electrode 16 (indicated by a broken line in the figure) and the segment electrode 1F (indicated by a solid line in the figure) from intersecting on the same substrate, the common electrode 16 is connected After routing the outside of the portion 15, the segment electrode 1T is connected to the common terminal 8.9 on the upper plate side via the connecting portion 15m, and the segment electrode 1T is drawn out to the upper plate side via the connecting portion 15m. ), the Fumon electrode 1 is routed on the lower plate.
Terminal 11#C is connected so as to straddle the drawer part of No.6.

As a result, the number of terminals was reduced to 32 as shown in FIG.

Note that each connection part 14 and 15Fi is formed of a conductive material such as Ag paste, but since the number of connections is equal to or greater than the number of terminals, it is not advisable to arrange them all at once outside the sealing material 3. stomach. That is, in this case, the distance between the connecting parts cannot necessarily be made large, and in addition, water droplets and the like may adhere, causing touch inconvenience due to the diffusion of Ag in the Ag paste. For this reason, this′! llll1 part 14°15Fi is formed inside the sealing material 3 or in the liquid crystal layer inside the sealing material 3 as shown in FIG.

5 and 6 respectively show the common electrode 12 constituting the exposed portion 4 on the upper plate side. Segment electrodes 13 and common electrodes 16 constituting the display section 5 on the lower plate side. Segment electric [Layout diagram showing 1F]

As shown in the figure, each electrode is composed of a comb-tooth portion forming a display pattern and a lead-out portion K for connecting to each terminal.

Here, the optimum pitch of the comb teeth of each common and segment electrode is 10 to 30 μtnlif.

Therefore, it is appropriate that the distance between the comb teeth of the common electrode and the comb teeth of the opposing segment electrode is 5 to 15 μm, and the distance p] between the two comb teeth is 3 to 13 μrm@degree.

(9) The distance between the upper and lower substrates, that is, the thickness of the liquid crystal layer is optimally 3 to 13 μtali in the case of homogeneous alignment in which liquid crystal molecules are arranged in parallel between the peripheral substrates. On the other hand, in the case of TN orientation, the minimum interval is limited to about 5 μm because the optical rotation may not be completed and color unevenness may occur. Further, in the case of the TN orientation, it is desirable to set the twist angle of the liquid crystal molecules to hto N110' from the viewpoint of obtaining high contrast.

Furthermore, compared to the conventional display using a pair of electrodes facing each other with a liquid crystal layer in between, the image display system was By using these together, you can diversify the display. For example, as shown in No. 7, the hour and minute display sections 18 and 151 are configured with comb-shaped electrodes on the upper plate, the second display section 20 is configured with comb-shaped electrodes on the lower plate, and the date display section 21 is configured with comb-shaped electrodes on the lower plate. By configuring it with opposing electrodes formed on both the upper and lower substrates, it is possible to provide a difference in the load resistance.

As explained above, the liquid crystal display device ff1i according to the present invention
According to K., a conductive connecting portion is provided between the peripheral substrates, and a part of the comb-shaped electrodes facing each other on the same substrate are drawn out onto the opposite substrate using the ribs to intersect three-dimensionally. By arranging K comb-shaped electrode pairs on each of the peripheral substrates sandwiching the two electrodes, and by reducing the number of terminals, it is possible to perform time-division driving. Therefore, while suppressing increases in IJI and bonding costs, it is possible to double the display function of the liquid crystal layer, and it also allows for overlapping display and individual display for each layer, increasing the degree of display freedom. can be increased. As a result, displays that were previously performed using two layers of liquid crystal can now be performed in one layer, reducing the cost of substrates and liquid crystals, and increasing transmittance by reducing the amount of light absorbed by the substrate and liquid crystal layer. It has various advantages such as the ability to obtain a bright device. have an effect.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a display example in an embodiment of the liquid crystal display device according to the present invention, and FIGS. 2 and 3 are connections of electrodes on the upper and lower sides of the liquid crystal display device shown in FIG. 1, respectively. 4 is a cross-sectional view of the liquid crystal display device of FIG. 1, and FIGS. 5 and 6 are front views showing the electrode arrangement on the upper and lower plate sides of the liquid crystal display device of FIG. 1, respectively. FIG. 7 is a front view showing a display example in another embodiment of the liquid crystal display device according to the present invention. 1...Top plate, 2-...Lower plate, 3--Sealing material, 4, 5, 18, 1! i, 20.21...Display section, 8,7,8,9...Common terminal, 10°11...
・-jml child, 12. lli...Common electrode, 13
, tsa #13b, 17, tra @
e @ m segment electrode, 14.15.15a...
...Connection part.

Claims (1)

[Claims] A liquid crystal display comprising a pair of comb-shaped electrodes with comb-shaped electrodes facing each other so that the molecular orientation of the liquid crystal layer near the substrates is changed by applying an electric field to both substrates facing each other with a liquid crystal layer in between. In the apparatus, a connecting part made of a conductor is provided between the circumferential substrates to connect them, and a part of one lead-out part of the comb-shaped electrodes facing each other on one board is led out onto the opposing board via the connecting part. . A liquid crystal display device, characterized in that it is configured to extend over the opposing substrate so as to straddle the other comb-shaped electrode on the one substrate.