JPS58184128A - Driving method of electrochromic display - Google Patents

Abstract

PURPOSE:To make discoloration response faster in an electrochromic display using a compd. resembling to styryl as a coloring material, by making the potentials in the initial period of a discoloration and during discoloration different. CONSTITUTION:A display is constituted of a display electrode 2, a counter electrode 4, a discolored display electrode 3, an electric power source 7 for discoloration, etc. The threshold voltage for coloration of a compd. resembling to styryl is 0.8V, and a driving voltage is applied in discoloring the display electrode which is applied with the voltage higher than the same (for example, about 2V) so as to color. The voltage differing from the voltage to maintain the discoloration in the initial period of discoloration is applied in this case. More particularly, the application of the voltage higher than the voltage in the initial period of discoloration is more preferable. The voltage for maintaining discoloration is 0V, and the electrode is discolored by said voltage but the discoloration response is faster if <=1.5V voltage is applied. The discoloration response is thus made faster.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a driving method for an electrochromic display device, and a driving method capable of speeding up the decoloring response of segment and character displays using a styryl-like compound as an electrochromic (hereinafter abbreviated as IECD) material. The purpose is to provide

The styryl-like compound used as the KID material used in the present invention has no viewing angle dependence, unlike conventional liquid crystals, and the area other than the display is white. This is because it is possible to produce colors that have not been removed beforehand, and it is also easy to create colors, and the current value is low.

On the other hand, the driving method is different from that of conventional RCDs.The following example of the present invention relates to segment display, but the principle is the same for character display.

In general, the conventional color display method in KCD is to temporarily apply a voltage to a decoded segment at the beginning of the decoding period, and then use the memory property, especially for a long color display segment. A driving force method in which the application is stopped is used.

When a styryl-like compound is used as a BOD material, it looks better than liquid crystal, and has features such as multicolor and lower current than conventional 0ECD, but the decoloring reaction is different from other ICCD materials, so it is difficult to drive. As for the methods, it is not possible to obtain sufficient results simply by using the same method.

The present invention speeds up the erasing response in an electrochromic display device using a styryl-like compound as a coloring material by making the potential at the beginning of erasing different from the potential during erasing.

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the basic structure of the electrochromic display device of the present invention, in which 1 is a transparent substrate made of glass or plastic, and 2 is a display 9 made of transparent electrodes such as indium dioxide tin oxide.

4 is a counter electrode also made of a transparent electrode; 3 is a decolored display electrode also made of a transparent electrode; 6 is a sealing portion; 6 is an electrochromic material.

Next, a method for driving this display device will be described. FIG. 2 shows a basic driving method. In FIG. 2, 2 is a display electrode, 4 is a counter electrode, 3 is a decoloring display electrode, and 7 is a power source for decoloring. The coloring threshold voltage of styryl-like compounds is o
, s V, when decoloring a display electrode that has been colored by applying a voltage higher than this (for example, about 2 V), as shown in Fig. 3 (a).
, (A driving voltage as shown in bl is applied. In Fig. 3 (a), the voltage that maintains decolorization is a DC voltage, and the voltage shown in Fig. 3 (a) is
b) is a case where the voltage for maintaining decolorization has a pulse waveform. In both cases, a voltage different from the voltage used to maintain decolorization is applied at the initial stage of decolorization. In particular, it is better to use a high voltage at the initial stage of decolorization. The decoloring maintenance voltage decolors even at oV, but the third
The decoloring response will be faster if a voltage is applied as shown in the figure. The voltage applied at this time is suitably 1.6v or less. Apply a voltage higher than this. Then the electricity [.

The poles are reduced and degraded. Furthermore, the longer the pulse application time, the faster the pulse waveform fades, but there is no major difference in the essential principle of the driving method of the present invention.

As described above, according to the present invention, the decoloring response can be accelerated.

[Brief explanation of the drawing]

Figure 1 is a sectional view of an electrochromic display device, Figure 2 is a cross-sectional view of an electrochromic display device;
The figure is a basic configuration diagram showing the driving method of the electrochromic display device of the present invention, and Figure 3 (!Ll, (bl is a voltage waveform diagram showing each embodiment of the present invention. Substrate, 2...Display electrode, 3.
...Counter electrode, 4...Third electrode, 6...
...Sealing part, 6...1ccn material, 7...
··power supply. Name of agent: Patent attorney Toshio Nakao and one other person
1 Figure 12

Claims (3)

[Claims] (1) A method for driving an electrochromic display device, which is characterized in that when decoloring an electrochromic display device having a coloring layer made of a styryl-like compound, the potential at the initial stage of decolorization is made different from the potential during decolorization. (2) Driving the electrochromic display device according to claim 1, wherein the potential waveform during decolorization is two types of potential pulse waveforms in the range of 0 to -1.6 V with respect to the counter electrode. Method. (3) The method for driving an electrochromic display device according to claim 1, wherein the voltage at the initial stage of color erasure is −1.6 V or less.