JPH0580295A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To provide the liquid crystal display device which is continuously varied in transmissivity between zero and an indicated value. CONSTITUTION:The liquid crystal display device consists of picture element electrodes 11, a common electrode 4, and liquid crystal 7 charged between those electrodes and is equipped with a driving circuit which generates a continuous potential slope between the indicated value and zero by applying each picture element electrode 11 with a voltage in three states, i.e., in-phase, opposite-phase, and high-impedance, i.e., open states about pulses applied to the common electrode 4 and makes the transmissivity similar to that of the periphery as the voltage varies from the indicated value to zero.

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 in which liquid crystal is sealed between opposing transparent insulating substrates having transparent electrodes.

[0002]

2. Description of the Related Art As a conventional liquid crystal display device, for example, there is one shown in FIG. In FIG.
Reference numerals 1 and 2 denote glass substrates which are first and second transparent insulating substrates which are arranged to face each other, 3 denotes a plurality of first transparent electrodes which are pixel electrodes provided on one glass substrate 1, and 4 denotes the other. A second transparent electrode which is a common electrode provided on the glass substrate 2, 5 and 6 are alignment films which regulate the orientation of liquid crystal molecules provided on the first and second transparent electrodes 3 and 4, and 7 is the glass substrate 1. , Liquid crystal sealed between the two, 8 is a conductive resin connecting the first transparent electrode 3 and the second transparent electrode 4 facing each other, 9 is a lead electrode connected to one end of the conductive resin 8, 10 Is a sealing resin that bonds the periphery of the glass substrates 1 and 2.

With such a configuration, the transmittance of the liquid crystal 7 is changed by selectively applying a predetermined voltage to the plurality of first transparent electrodes 3, and each of the plurality of first transparent electrodes 3 is formed into a pixel. The image can be displayed.

[0004]

However, in such a conventional liquid crystal display device, when a display in which the transmittance is continuously changed is performed, the pulse supplied to each pixel electrode is complicated by duty control or the like. There is a problem in that the driving circuit of the pixel electrode becomes complicated because it is necessary to individually control the effective value of the voltage by using a method. Also, since the pixel electrode is separated with a predetermined size corresponding to the shape of the display pixel, the transmittance can be changed for each display pixel, but the transmittance is continuously from zero to the indicated value. Even if an attempt is made to display the indicated value clearly by changing the ratio, the display pixels have the same transmittance, and since there is a portion that cannot be displayed between the pixels, a neat display screen is displayed. There was a problem that I could not get it.

The present invention has been made to solve the above problems, and pixel electrodes are connected to each other by a conductive thin film layer so that the transmittance between zero and the indicated value is continuously obtained. An object is to obtain a liquid crystal display device that is changed.

[0006]

A liquid crystal display device according to the present invention is provided with a second transparent insulating substrate facing a first transparent insulating substrate and the first transparent insulating substrate, and has a low resistance. A pixel electrode formed by a plurality of strip-shaped transparent electrodes and a high-resistance conductive thin film layer connecting the plurality of transparent electrodes, and a pixel electrode that is arranged to face the pixel electrode and is provided on the second transparent insulating substrate. A common electrode, a liquid crystal provided between the first transparent insulating substrate and the second transparent insulating substrate, and a pulse supplied to the common electrode for the electrode corresponding to the indicated value among the pixel electrodes. A pulse of the opposite phase, a pulse of the same phase as the pulse of the common electrode on the adjacent electrode on the higher value side than the electrode corresponding to the indicated value, and a pulse of the common electrode on the electrode displaying zero value. In-phase and variable voltage pulse Supplies, supplied without electrode of the pulses is made of a driving circuit for the electrically insulated.

[0007]

In the liquid crystal display device according to the present invention, the in-phase, anti-phase and high impedance of the pulse for applying the drive circuit of the liquid crystal display to the common electrode, that is, the open state is arbitrarily supplied to the pixel electrode of the indicated value. By making the transmittance sharply different from that of the surroundings and applying a voltage to each pixel electrode so that the transmittance becomes similar to that of the surroundings as it goes from the indicated value to the zero value, A continuous potential gradient is generated between the value and the value, and the transmittance of the liquid crystal is continuously changed according to the potential gradient.

[0008]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. 1 is a front view showing an embodiment of the present invention, FIG. 2 is a sectional view taken along the line II-II of FIG. 1, and FIG. 3 is a block diagram showing a driving device of the present invention. The same or equivalent components will be assigned the same reference numerals and overlapping description will be omitted. In the figure, 11 is a pixel electrode, which is composed of a plurality of strip-shaped transparent electrodes 12 and a conductive thin film layer 13 connecting the plurality of transparent electrodes 12. 14a to 14n _-1 , 14n, 14n _{+1 to} 14m are extraction electrodes connected to the transparent electrodes 12 of the pixel electrode 11, respectively. Reference numeral 15 is a drive circuit for driving the extraction electrodes 14a to 14m, 16 is a display controller for controlling the drive circuit 15, and the display controller 16 processes the measurement signal by a microcomputer or the like to form the pixel electrode 11 and the common electrode 4, It controls the display of a liquid crystal display composed of the liquid crystal 7 sealed between these electrodes.

Therefore, the drive circuit 15 oscillates a common pulse, the oscillator 17 connected to the common electrode 4, and the buffers 18a, 1 to which the outputs Q, Q of the oscillator 17 are supplied.
8b and a variable resistor 19 connected to the extraction electrode 14a
And the three-state buffers 20a, 20b, ..., 20m which are controlled by the display controller 16 and are connected to the extraction electrodes 14b to 14m. The pixel electrode 11 receives the output signal from the display controller 16. To the common electrode 4 in any of three states: in-phase, anti-phase, and high impedance. The output Q of the oscillator 17 is the pulse of the common electrode 4, and the output bar Q
Is an antiphase pulse of the common electrode 4 of output Q.

Next, the operation will be described. The voltage shown in FIG. 4A is applied from the drive circuit 15 to the plurality of extraction electrodes extracted from the pixel electrode 11 composed of the low-resistance transparent electrode 12 and the high-resistance conductive thin film layer 13. That is, the three-state buffer 2 at the output stage of the drive circuit 15
By controlling the control terminals of 0a, 20b, ..., 20m by the display controller 16, a voltage having the same phase as the voltage waveform applied to the common electrode 4 is applied to the extraction electrode 14n _{+ 1} , and the extraction electrode 14n _{+ 1} is applied. Is applied with a voltage having a phase opposite to that of the voltage waveform applied to the transparent electrode 4. Further, no voltage is applied to the extraction electrodes 14b to 14n _-1 and the extraction electrodes 14n _{+2 to} 14m, and they are brought into an open state. Further, the extraction electrode 14a is applied with a pulse having a voltage having a common pulse width of 1/2 as a DC bias and whose amplitude can be arbitrarily changed. This output pulse is shown in Figure 4.
It can be arbitrarily changed by changing the variable resistor 19 as shown in (b).

Considering the voltage applied to the liquid crystal 7 at this time (that is, the difference between the voltages applied to the pixel electrode 11 and the common electrode 4), the liquid crystal 7 sandwiched between the extraction electrodes 14n _{+2 to} 14m and the common electrode 4 is considered. There is no voltage applied to it. Extraction electrode 1
Since 4n and the common electrode 4 have opposite phases, the liquid crystal 7 sandwiched between them has a voltage difference between the electrodes. Since the extraction electrode 14a and the common electrode 4 have the same phase, the difference between the DC bias voltage of the common pulse width appropriately changed by the variable resistor 19 and the voltage applied to the common electrode 4 is applied to the liquid crystal 7 sandwiched between the two. Is applied to the extraction electrodes 14b to 14
between n and the common electrode 4 and the extraction electrodes 14n to 14n
_An intermediate voltage is applied to the liquid crystal 7 between ₊₁ and the common electrode 4 (see FIG. 4 (c)).

As described above, the transmittance of the liquid crystal display is determined by the voltage applied to the liquid crystal 7. Therefore, by applying a DC bias voltage to the extraction electrode 14a indicating the zero value, the zero value is obtained as in the conventional case. There is no longer a case where the transmittance of the liquid crystal 7 becomes zero from the electrode prior to the pixel electrode 11 which indicates., And the indication of the zero value becomes unclear, and it is possible to clearly indicate from the zero value to the indicated value.

As for the change in transmittance, as shown in FIG. 5 in the case of positive display and in the case of negative display as shown in FIG. 6, there is no discontinuity between the pixels and the display brightness is gradually changed. can do.

Needless to say, the display state can be changed by changing the position to which the reverse phase voltage is applied from the extraction electrode 14n to the extraction electrode 14n _{+ 1} . Further, by changing the DC bias of the extraction electrode 14a to which the common mode voltage is applied, the continuous potential inclination angle between the indicated value and the zero value can be arbitrarily changed.

Next, another embodiment will be described with reference to FIGS. 7 and 8 show the transparent electrodes 12 of the pixel electrodes 11 arranged substantially in parallel. 9 and 1
0 indicates that the same voltage as that in the first embodiment is applied to each extraction electrode, and the display state is a bar graph display in which the tail of light is drawn. The transparent electrode 12 and the conductive thin film layer 13 that form the pixel electrode 11 of the liquid crystal display may be configured as shown in FIG.

[0016]

As described above, according to the present invention, the structure is provided in the second transparent insulating substrate arranged to face the first transparent insulating substrate and the first transparent insulating substrate, A pixel electrode formed by a plurality of thin strip-shaped transparent electrodes having a low resistance and a conductive thin film layer having a high resistance for connecting the plurality of transparent electrodes, and the second transparent insulating substrate which is arranged to face the pixel electrode. The common electrode provided on the pixel electrode, the liquid crystal provided between the first transparent insulating substrate and the second transparent insulating substrate, and the electrode corresponding to the indicated value among the pixel electrodes is supplied to the common electrode. Pulse having a phase opposite to that of the pulse, the pulse having the same phase as the pulse of the common electrode on the adjacent electrode on the higher value side than the electrode corresponding to the indicated value, and the common electrode on the electrode displaying the zero value. In-phase with the pulse of and the voltage can be changed Along with supplying a pulse, since the electrode to which the pulse is not supplied is provided with a drive circuit for electrically insulating the pixel electrode, the pixel electrode is integrally formed, and display with continuous brightness change can be performed with a simple circuit configuration. Further, the effect that the display from the zero value to the indicated value can be made clear is obtained.

[Brief description of drawings]

FIG. 1 is a front view showing a liquid crystal display device according to a first embodiment of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a block diagram showing a driving device according to a first embodiment of the present invention.

4 (a) to 4 (c) are voltage waveform diagrams for explaining the operation of FIG.

FIG. 5 is a front view showing a display example 1 of the first embodiment of the present invention.

FIG. 6 is a front view showing a second display example of the first embodiment of the present invention.

FIG. 7 is a front view of a main part showing a second embodiment of the present invention.

FIG. 8 is a front view showing a display example of the second embodiment of the present invention.

FIG. 9 is a front view of the essential parts showing a third embodiment of the present invention.

FIG. 10 is a front view showing a display example of the third embodiment of the present invention.

FIG. 11 is a plan view showing a fourth embodiment of the present invention.

FIG. 12 is a front sectional view showing a conventional liquid crystal display device.

[Explanation of symbols]

 1 1st transparent insulating substrate 2 2nd transparent insulating substrate 4 common electrode 7 liquid crystal 11 pixel electrode 12 transparent electrode 13 conductive thin film layer 15 drive circuit

Claims (1)

[Claims] 1. A second transparent insulating substrate arranged to face the first transparent insulating substrate, a plurality of thin strip-shaped transparent electrodes provided on the first transparent insulating substrate and having low resistance, and the plurality of transparent electrodes. A pixel electrode formed by a high-resistance conductive thin film layer connecting between the pixel electrode, a common electrode provided on the second transparent insulating substrate and facing the pixel electrode, the first transparent insulating substrate, and the first transparent insulating substrate. 2 A liquid crystal provided between the transparent insulating substrate and the pixel electrode corresponding to the indicated value of the pixel electrode is provided with a pulse having a phase opposite to the pulse supplied to the common electrode and corresponding to the indicated value. A pulse having the same phase as the pulse of the common electrode is supplied to the adjacent electrode on the higher value side than the electrode, and a pulse having the same phase as the pulse of the common electrode and having a variable voltage is supplied to the electrode displaying the zero value. , Electrodes not supplied with the above pulse Is a liquid crystal display device including a drive circuit that is electrically insulated.