JPS60175035A - Driving device of electrochromic element - Google Patents

Abstract

PURPOSE:To drive a matrix without crosstalk by connecting bidirectional voltage nonlinear elements in series to display electrodes of individual electrochromic elements. CONSTITUTION:Bidirectional voltage nonlinear elements Zij where diodes are connected in opposite directions in parallel are connected in series to individual electrochromic display elements ECDs Cij to constitute the matrix; and when voltage 1V of 1sec is applied to a row line X1 is applied between a the display electrode C11 and a counter electrode. In this case, the electrode C11 is colored but display electrodes C21, C22, and C12 are not colored; and if voltages 0V and +2V are applied to lines X1 and Y2 in this state, electrodes C11 and C12 are colored but electrodes C21 and C22 are not colored. If voltages 0V and +2V are applied to lines X2 and Y1 in the state where the electrode C11 is colored, the electrode C22 is not colored; and therefore, crosstalk is avoided.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an electrochromic display device (hereinafter referred to as ECD) using an electrochemical redox reaction, and in particular, to an electrochromic display device (hereinafter referred to as ECD) that uses an electrochemical redox reaction. The present invention relates to a drive device for a display element in an electrochromic display device that displays arbitrary characters or figures.

Conventional Example and its Problems Since the ECDti coloring density depends on the applied voltage, it does not have a clear coloring voltage threshold. Therefore, multiple 0ECD
When arranging them in a matrix and driving them, a closed circuit including multiple 0ECDs connected by lines in rows and columns is formed, and ECDs other than the target ECD are also colored.
There is a problem that a so-called tarostota occurs.

OBJECTS OF THE INVENTION The object of the present invention is to provide a coloring (or decoloring) voltage threshold in order to prevent the above-mentioned talostator, thereby realizing matrix drive without talostator.

Components of the Invention As shown in FIG. 5, the present invention has a bidirectional voltage nonlinear element connected in series to the display electrode or counter electrode of each element of a plurality of ECDs arranged in a matrix. be.

DESCRIPTION OF THE EMBODIMENTS The voltage-current characteristics of the ECD are shown in FIG. , when the voltage is swept in the negative direction, a negative current flows through the display electrode and it becomes colored.When the voltage is swept in the positive direction when it reaches -IV, the negative current starts to decrease and the current flows in the positive direction. thing,
The stream begins to flow.

The current in the positive direction also decreases after passing OV and almost no longer flows. Like most ECDs, the coloring density is proportional to the amount of electricity injected into the display electrodes of the ECD, so there is no precise coloring voltage threshold.

Therefore, when we insert a bidirectional voltage nonlinear element in series with the ECD, for example, two silicon diodes connected in parallel in opposite directions, and measure its voltage-current characteristics, the result is as shown in Figure 1 (bl). ff1J, when the display electrode voltage is swept, at -700 mV 1, no current flows in the negative direction, and the ECD is not colored. -8o.

A negative current starts flowing from around mV, and after reaching -2V, when the voltage sweep direction is reversed, the negative current decreases and -
It becomes almost 0 at iv. Current does not flow up to Ov in the length,
After passing 0■, the current starts to flow in the positive direction, and the amount of electricity that flows in the negative direction flows. This Koyoshi ECD has a coloring (or decoloring) voltage threshold.

Next, the manner in which Talostalk occurs in the conventional matrix-driven ECD shown in FIG. 2 will be explained. Now, the second
In the figure, a voltage of OV+'l'a6c is applied to the row line X, and +1v is applied to the column line Y in synchronization with X□.
, If Y2 is left open, C work and 0ECD will be colored,
C21°C engineering. , C22 ECD and no coloring. If the connection status of each ECD at this time is rewritten, it will become as shown in Figure 3(at).

Next, leave C work colored, add ov to X work, and add + to K2.
When 1v is applied, NCLI is colored while Cu remains colored.

And C21 and Cyu are not colored. The state at this time is the third
The result will be as shown in figure (b).

Also, while keeping Cu in color, add +1 to X, OMY□
When the voltage is applied, the connection state at this time becomes as shown in FIG. 5 (cl), and C2□ is colored, but the coloring contrast of Cu is lowered, and C22 is slightly colored.

These phenomena are caused by EC as known from Figure 1(a).
When no electricity is injected into the display electrode of D, K1-1
', this is explained by the fact that no current flows even if a positive voltage is applied to the opposing electrode. On the other hand, as shown in FIG. 1(c) K, the voltage-current characteristic of only the opposing electrode shows that current flows regardless of the direction of the voltage. That is, in the case of FIG. 5(a), Cn
When a voltage is applied between the display electrode and the counter electrode of C2
1. If Cepr and Qxr are not colored, C2
Since no electricity is injected into the display electrodes □ and C4, no current can flow between them. The same applies to the case of FIG. However, as shown in Figure 3 (in the case of CL, C is colored, and therefore a current can flow between Cu and 6, an electrical loss equivalent to 10.35 V is injected into C21. Therefore, it is thought that it is slightly colored.

Purpose of trying to color in this way ECD other than 0 ECD
In order to prevent so-called talostalk, which is caused by coloring, a bidirectional voltage nonlinear element 2, which has silicon diodes connected in parallel in opposite directions as shown in Fig. 4, is connected in series to each ECD, as shown in Fig. 5. When the matrix of the present invention is configured as shown in FIG.
IV is applied between the display electrode and the counter electrode of C□. Figure 6 shows the closed circuit created in each ECD mJ constituting the IJ Fuchs shown in Figure 5.

In the circuit of FIG. 5, the above-mentioned two FIG.
), (When we conducted an experiment by applying the same voltage as described above for cl, we found that a voltage of OV + 1 sec was applied to the X side and a voltage of +2V was applied to the Y side. With KFi and C□□ colored, C, C2□, and C not colored, and C-work colored, ov to X□,
Figure 5 (b) where a voltage of +2v is applied to K2 When it corresponds to K, C□□ and C are colored, and C2□ and C22
is not colored, and C is colored, and it is oved to K2.
In the case corresponding to FIG. 5(c)K in which a voltage of +2V was applied to , y□, no coloration was observed in C22.

This can be said to mean that Talostalk had not occurred.

Effects of the Invention According to the present invention, an ECD is created by a closed circuit created between a plurality of ECDs constituting a matrix with a simple S configuration.
ff! The movement of the electricity h1 of 11 is prevented, so that Talostalk can be eliminated and the memory function of the ECD can be maintained.

[Brief explanation of drawings]

Figure 1(a) shows the voltage-current characteristics of the ECD, Figure 1(b) shows the voltage-current characteristics when a bidirectional voltage nonlinear element is connected in series with the ECD, and Figure 1(c) shows the voltage-current characteristics of the ECD facing the ECD. Figure 2 shows the voltage-current characteristics of the electrode alone, and Figure 2 shows the conventional 0ECD matrix circuit;
c) is an explanatory diagram of the operation of the circuit of FIG. 2, FIG. 4 is an equivalent circuit of an example of a bidirectional voltage non-plane linear element used in the present invention, and FIG. 5 is an example of an electrochromic display device according to the present invention. The circuit diagram of the embodiment, FIG. 6, is a rewritten version of FIG. 5. x,, x2-...line between rows, Y, Y2-=column line,
Cu, C12, C21°C2□... Electrochromic element, 2,211, 2nd work 2. Zm. Z22 -- Bidirectional voltage nonlinear element. Name of agent: Patent attorney Etsuji Yoshizaki Figure 2 (b) (C) Figure 5 Figure 6 Figure 4

Claims (1)

[Claims] In a device in which a plurality of electrochromic elements are arranged in a matrix and a desired figure is displayed by coloring or decoloring the plurality of electrochromic elements, a bidirectional electrode is connected in series to the display electrode or counter electrode of each electrochromic element. A driving device for an electrochromic element, characterized in that a voltage nonlinear element is connected.