JPS6066238A - Optical color developing element - Google Patents

Abstract

PURPOSE:To make it possible to write a fine high-density pattern with a weak light, by constituting a double-layered structure consisting of a color developing layer and an ion supply source and irradiating this element with light while applying a fine electric field to it. CONSTITUTION:A color developing layer 1 and an ion supply source 2 are provided close to each other, and they are held between ultraviolet ray-transmissive electrodes 3 and 4. When light 6 is irradiated while applying a weak electric field, ultraviolet rays 6 pass through the ultraviolet ray-transmittable electrode 3 and act upon an interface 7 between the color developing layer and the ion supply source. This optical energy gives an energy E to cause a reaction, and color develops only in a part 8 to which the light is irradiated. Thus, a fine high-density pattern can be written with a weak light. When an electric field having a polarity opposite to that for color development is applied, the color developing part is erased easily.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to erasable optical color elements useful for fine, high-density optical memories, displays, and the like.

Conventional Structure and Problems Conventionally, an electrochromic element known as an optical coloring element generates and erases a color using an electric field, and forms a colored pattern depending on the shape of the electrode. When forming electrodes, there is a limit to the fineness of the pattern - it is necessary to take out the leads, so there is also a limit to the density.

It is difficult to apply it to optical memories, displays, etc. that require fine, high-density patterns, and it has only been used as a simple display element. In addition, most conventional optical memories use heat to cause structural changes, and only a few can be erased. was not sufficient for practical use. The inventors discovered that when light is irradiated onto a color-forming element having a two-layer structure in which a color-forming layer and an ion source are brought into close contact while applying a weak electric field in the thickness direction of the two-layer structure, the portion irradiated by the light It was discovered that this colored part can be erased by applying an electric field of opposite polarity to the coloring part to the above two-layer structure. Invented a unique optical coloring element.

OBJECTS OF THE INVENTION It is an object of the present invention to provide an optical coloring element on which fine, high-density patterns can be written and which can be easily erased.

Structure of the Invention The optical coloring element of the present invention has a two-layer structure consisting of a coloring layer and an ion supply source provided in close contact with the coloring layer, in which a weak electric field is applied in the thickness direction of the two-layered structure. It is characterized by developing color by irradiating light while applying light. A further feature is that the color is erased by applying an electric field of opposite polarity to the coloring state to the two-layer structure.

The electric field applied when coloring with light is suitably in the range of 6% to 60% of the electric field applied during erasing. Due to the weak electric field applied during the above color development, the light irradiated during the above color development can be colored even with 9 weak light, which is 1/10 to i/+o of the case where no weak electric field is applied.

Color development is now possible with light of the following intensity.

The inventors have confirmed that when irradiating light to develop color, the use of ultraviolet light having a wavelength of 600 nm or less can particularly effectively develop color. Further, a pair of electrodes, at least one of which is transparent to ultraviolet light, is provided between the two-layer structure, and light is irradiated through the electrodes that are transparent to ultraviolet light to cause color development.

The inventors have also discovered that when the electric field is applied to the double layer to erase color by applying a voltage between the electrodes, the electric field is applied more effectively to the double layer, and it is possible to erase the misalignment at a low voltage. confirmed. moreover.

The above-mentioned coloring layer is a sputtered film of a mixed oxide of lithium and tungsten in an argon atmosphere (a lid film is used as the ion supply source); It was confirmed that it is particularly effective as an optical coloring element of the present invention.If an -ITO film is used as an electrode that is transparent to ultraviolet light, the transparency in the visible region is also good, and it is also particularly effective. confirmed.

Description of examples FIG. 1 shows a first embodiment of the optical coloring element of the present invention.

The coloring layer 1 and the ion source 2 are placed in close contact and sandwiched between electrodes 3 and 4 that are transparent to ultraviolet light.

Although this four-layer structure is formed on the substrate 6, the substrate 6 is not necessarily required if it is mechanically stable. Further, the electrodes 3.4 are not necessarily required as long as a sufficient electric field is applied to the two-layer structure of the coloring layer 1 and the ion source 2. The coloring layer 1 reacts with ions supplied from the ion supply source 2 to develop color. During the reaction, the state A in which the substances and ions in one color-forming layer coexist to the state in which they react with each other and develop color must cross the energy wall A, as shown in Figure 2, so one energy Energy corresponding to the wall height E is required.

At the time of color development, the state of the substance and ions in the first color development layer is slightly excited in terms of energy by a weak electric field applied in the thickness direction of the 12-layer structure, and becomes energy e -5tate in the electrophase diagram 2. In order to overcome the energy wall from this state, it is only necessary to apply energy E'' (Fig. 2), and compared to the energy wall E when the weak electric field is not applied, the wall requires less energy. It is possible to react and develop color by exceeding the energy E.
The principle of color development of the present invention is to cause the color development layer 1 to develop color by providing " with light."

In the case where the above-mentioned weak electric field is not applied, strong light capable of imparting a large energy of one above E is required to cause one reaction.

In the present invention, a reaction can be caused even with weak light that can provide a small amount of energy, such as E".

It can be colored.

As shown in FIG. 3, when the light 6 is irradiated while applying the above-mentioned weak electric field, the ultraviolet light 6 passes through the electrode 3 which is transparent to ultraviolet light and acts on the interface γ between the coloring layer and the ion source.

The energy of this light gives the above-mentioned energy E", and one reaction occurs, and only the area 8 that was irradiated with light develops color. The details of this reaction are unknown, but due to the above-mentioned mechanism, the area that was irradiated with one shot develops color. It is thought that the coloring section 8 applies an electric field of opposite polarity to the one for coloring to the two-layer structure.In other words, by applying a voltage of opposite polarity to the one for coloring to the electrodes 3.4, the coloring is erased. and returns to the state before one color was developed.When erasing.

It is thought that a reaction opposite to the above reaction occurs, and is caused to occur by applying an electric field that provides energy greater than the energy wall (E' in FIG. 2).

A sputter-deposited film of the J-W-0 mixture in an Al atmosphere is used as the coloring layer, and a Ll-W-
When using an ITO film with a sputter-deposited film in an AI-02 atmosphere as one electrode, a mercury lamp was used as the light for producing one color, and a voltage of 2V was applied with the color-producing layer side set to - at 60 mJ/, , p.

When irradiated at a certain density, it developed a blue color. This color development can be done by setting the color development layer side to the above ITO electrode as "= (plus)".
It could be erased by applying a voltage of v. The film thickness was approximately 5,000 layers including the coloring layer and ion source.

At the time of color development, it was observed that the intensity of the transmitted light of the -He-Ne laser beam (6328 people) was attenuated by 10 dB or more, forming a colored part of a single color. When a voltage of 6 V was applied to the electrode and erased by the electric field, the state returned to the state before the first color was developed, and the transmitted light intensity was the same as the transmitted light intensity of the He-Ne laser beam in the state before the first color was developed. Here, specifically Li -W-0
Although only the sputtered film of the mixture is shown, the two-color developing layer may be made of a so-called electrocomic material, and the ion supply source is not limited to the above-mentioned materials. The ion supply source may be not only solid but also liquid, as long as it contains ions that act on the electrocomic material.

The irradiation light is not limited to one excimer laser, but may be any light that provides energy greater than the energy barrier for one reaction. Ultraviolet light with high energy is effective. By focusing the irradiated light with a lens, it is possible to develop a fine pattern of approximately 1 μm in color. It is also possible to write complex patterns by scanning light. Effects of the Invention As described above, the present invention provides a coloring element having a two-layer structure consisting of one coloring layer and an ion supply source provided in close contact with the coloring layer. By applying light while applying a weak electric field, color is generated, and a fine, high-density pattern can be realized with weak light. Also.

By applying an electric field of opposite polarity to that during color development.

The colored portion can be easily erased, and an erasable optical coloring element that is effective for fine, high-density optical memories, displays, etc. can be realized.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional structural diagram of the optical coloring element of the present invention, and FIG.
The figure is an energy diagram of the optical coloring element of the present invention in each state, and FIG. 3 is a diagram of the coloring operation of the optical coloring element of the present invention due to light. 1.--Coloring layer, 2. Group/ion supply source, 3.
4...electrode, 6...substrate, 6...
...Light (ultraviolet light).

Claims (1)

[Scope of Claims] (1) It has a two-layer structure consisting of a color-forming layer and an ion supply source provided in close contact with the color-forming layer, and a weak electric field is applied in the thickness direction of the two-layer structure and light is emitted. An optical coloring element that develops color by being irradiated with. (2) A patent claim characterized in that the colored portion is decolored by applying an electric field of opposite polarity to that during coloring to a two-layer structure consisting of a coloring layer and an ion supply source provided in close contact with the coloring layer. The optical coloring element according to item 1. (3) The optical coloring element according to claim 2, wherein ultraviolet light having a wavelength of 6 Q Q 11 m or less is used as the light. (4) A pair of electrodes, at least one of which is transparent to ultraviolet rays, are provided sandwiching a two-layer structure consisting of a coloring layer and an ion supply source provided in close contact with the coloring layer. An optical coloring element according to claim 1 or 2. (6) As a coloring layer, a sputtered film of a mixed oxide of lithium and tungsten in an argon/oxygen atmosphere is used as an ion supply source, using a sputtered film of a mixed oxide of lithium and tungsten in an argon/oxygen atmosphere. An optical coloring element according to claim 1 or 2. (6) The optical coloring element according to claim 4, characterized in that an -ITO film is used as the electrode that is transparent to ultraviolet rays.