JPS6148137B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for displaying interference colors by electrical means.

Conventionally, as methods for displaying by electrical means, there are active display methods such as display tubes and lamps using EL and ELD, and passive display methods using electrochromy, liquid crystal, etc. The present invention is a novel type of display method not found in conventional methods, and is characterized by color display, change in display color depending on the observation point, and display memorability.

Specifically, by applying current between the electrodes of an element formed by sandwiching a solid layer containing a transition metal compound between a pair of electrodes, one of which is transparent and the other is reflective, A metal semi-transparent film layer is formed on the light-transmitting electrode, and an interference color caused by an optical path difference between the light reflected by the metal semi-transparent film layer and the light reflected by the light-reflecting electrode is displayed. This is a display method characterized by:

Hereinafter, the display method of the present invention will be explained by giving specific examples with reference to the drawings.

FIG. 1 shows an example of a device according to the present invention.

In Figure 1, 1 is glass, acrylic resin, CaF ₂
It is a light-transmitting substrate made of a material such as the like, and also serves to protect the inner layer, but it is not necessarily necessary in the present invention. 2 is a layer of a transparent conductive material, preferably one having high electronic conductivity. For example, it is a vapor deposited film of SnO ₂ , TiO ₂ , In ₂ O ₃ or the like.

Layer 3 is preferably made of a material having a lower electronic conductivity than layer 2, and can be formed into a transparent thin film by vapor deposition, CVD, sputtering, or the like. For example, it is selected from the following transition metal compounds.

ZrO Bi ₂ O ₃ Nb ₂ O ₅ ReO ₇ PbO CeO Ta ₂ O ₅
RaO ₄ MgO ZnO Sb ₂ O ₃ CsO ₄ Ni ₂ O ₃ V ₂ O ₃
Cr ₂ O ₃ Co ₂ C ₃ CdO GaO MoO ₃ Sb ₂ S ₃ Ag ₂ O
Ga ₂ O ₅ TeO ₂ IrS HgO Pb ₂ O ₅ MnO ₂ GaS CoS
NH ₄ VO ₃ CuCl H ₃ [PMo ₁₈ O ₄₀ ] 30H ₂ O HgS Pb
(NO ₃ ) ₂ ZnCl ₂ SnS Fe (NO ₃ ) ₃ H ₂ SbO ₅ H ₃
[PW ₁₂ O ₄₀ ]・30H ₂ O WS ₂ Ni(NO ₃ ) ₂ H ₂ SeO ₄
K ₂ MoO ₄ PtS Cr(NO ₃ ) H ₂ MoO ₄ Na ₂ MoO ₄
PdS Zn(NO ₂ ) ₂ H ₂ WO ₄ Na ₂ Mo ₃ O ₂₅・17H ₂ O
MnS Sr(NO ₃ ) ₂ H ₃ SbO ₄ (NH ₄ ) ₂ MoO ₄ MoS
Pb (NO ₃ ) ₂ H ₄ TiO ₄ Na ₄ [Mo ₃ O ₂₅ ]・12H ₂ O RhS
(NH ₄ ) ₃ [P(Mo ₃ O ₁₀ ) ₄ ] (NH ₄ ) ₅
[Mo ₇ O ₂₇ ]・4H ₂ O BeCl ₂ H ₄ [Si(Mo ₃ O ₁₀ ) ₄ ]
(NH ₄ ) ₆ [Ca ₂ Mo ₁₂ O ₄₅ ]・2H ₂ O AgCl AgNO ₃
H ₄ MoO ₆ BiCl ₃ PZT H ₄ Sb ₂ O ₇ H ₂ SeO ₃ InCl ₃
MgCl ₂ H ₅ SbO ₅ H ₂ TeO ₃ SbCl ₄ NiCl ₂ H ₅ TeO ₆
H ₂ TiO ₅ CeCl ₃ NbCl ₅ H ₁₀ SnO ₁₅ Mn(NO ₃ ) ₂
CuCl ₃ H ₄ [SiMo ₁₈ O ₄₀ ] 30H ₂ O Furthermore, in the present invention, the composition ratio of the ternary compounds listed below is not specified, and a wide range of compositions can be used.

Li-Ti-O compound Na-Ti-O compound K -Ti-O 〃 Ca-Ti-O 〃 Sr-Ti-O 〃 Ba-Ti-O 〃 Li-W -O 〃 Na-W -O 〃 K - W -O 〃 Ca-W -O 〃 Sr-W -O 〃 Ba-W -O 〃 Li-V -O 〃 Na-V -O 〃 K -V -O 〃 Ca-V -O 〃 Sr-V - O 〃 Ba-V -O 〃 Li-Mo-O 〃 Na-Mo-O 〃 K -Mo-O 〃 Ca-Mo-O 〃 Sr-Mo-O compound Ba-Mo-O compound Li-Nb-O 〃 Na−Nb−O 〃 K −Nb−O 〃 Ca−Nb−O 〃 Sr−Nb−O 〃 Ba−Nb−O 〃 Li−Ta−O 〃 K −Ta−O 〃 Na−Ta−O 〃 Ca− Ta−O 〃 Sr−Ta−O 〃 Ba−Ta−O 〃 Li−Zn−O 〃 Na−Zn−O 〃 K −Zn−O 〃 Ca−Zn−O 〃 Sr−Zn−O 〃 Ba−Zn− O 〃 Li−Sn−O 〃 Na−Sn−O 〃 K −Sn−O 〃 Ca−Sn−O 〃 Sr−Sn−O 〃 Ba−Sn−O 〃 Li−Cr−O 〃 Na−Cr−O 〃 K -Cr-O 〃 Ca-Cr-O 〃 Sr-Cr-O 〃 Ba-Cr-O 〃 Li-Mn-O 〃 Na-Mn-O 〃 K -Mn-O 〃 Ca-Mn-O 〃 Sn- Mn-O 〃 Ba-Mn-O 〃 Li-Fe-O 〃 Na-Fe-O 〃 K -Fe-O compound Ca-Fe-O compound Sr-Fe-O 〃 Ba-Fe-O 〃 Li-Co- O 〃 Na−Co−O 〃 K −Co−O 〃 Ca−Co−O 〃 Sr−Co−O 〃 Ba−Co−O 〃 Li−Ni−O 〃 Na−Ni−O 〃 K −Ni−O 〃 Ca−Ni−O 〃 Sn−Ni−O 〃 Ba−Ni−O 〃 Li−In−O 〃 Na−In−O 〃 K −In−O 〃 Ca−In−O 〃 Sr−In−O 〃 Ba− In-O 4 is a light-reflective electrode, and various metals can be used, but those that satisfy the following conditions are preferable.

(a) A material that does not easily cause a chemical reaction with the material of layer 3 above.

(b) High light reflectance and uniform spectral sensitivity at each wavelength.

(c) Good exchange of electrons with the layer 3 above.

5 is a power supply, and 6 is a polarity changeover switch.

In the first illustrated example, the light emitted from the light source 7 is A,
It reaches the observation eye 8 via points C and D. (in this case,
Layers 1, 2, and 3 are all translucent, and layer 4 is reflective. ) Note that it is also possible to apply an anti-reflection film to the surface of the first layer to prevent surface reflection at point A, or to prevent interface reflection at point C by selecting the material of each layer. You can also do it.

If the above selection conditions are satisfied, most of the light from the light source 7 will reach the viewing eye through reflection at point D. Next, when electricity is applied between the 2nd and 4th layers from the polar power source 5 through the switch 6, a colored state is instantaneously brought about.

The reason for this is considered to be that a metal semi-permeable film layer is formed at the interface due to an oxidation-reduction reaction between the second layer and the third layer, and the reflectance at point C becomes high. Therefore, by instantaneous energization, the reflected light at point D and the reflected light at point C reach the observing eye, and interference colors based on them are observed. This interference color is preserved even after the power to the element is cut off, and has a so-called memory property. Keeping in mind that the interference in the present invention is neither due to electrically induced film thickness changes nor to changes in refractive index, after removing the fourth and third layers of the device by chemical treatment, , by X-ray analysis 2
This is confirmed by the fact that a metal thin film is observed to be formed on the layer.

Also, interference on surfaces other than C to D is also considered,
For those in which the film thicknesses of layers 1, 2, and 3 are changed (actually, the film thickness is gradually changed by moving the mask during vapor deposition), devices are created by considering all combinations of film thickness changes. As a result of research, C~
It turned out to be interference between D. When the element, which has become colored due to the previous energization, is energized with the opposite polarity, the polarization state in the three layers becomes opposite to the previous one, and the reflectance at point C decreases, returning to the original state. to return to. Therefore, the viewing eye 8 observes the decolored state.
In addition, in the present invention, when the observation position is changed while the color is developing as in the second illustrated example, F,
Interference colors are generated due to the optical path difference with the reflected light from points F', G, and G', and since the optical path difference differs depending on the observation position, the interference colors at points 8' and 8'' of the observing eye are different. Another feature of the present invention is that the color can be freely changed by controlling the thickness of the three layers.

Hereinafter, the present invention will be explained in further detail with reference to Examples.

Example 1 After cleaning, In ₂ O ₃ was evaporated onto a dried glass substrate and heat treated to obtain a transparent electrode. Then on the deposited film
Performed electron beam evaporation of ZrO ₂ to a film thickness of 5900 Å.
Four types were created: 3700Å, 3500Å, and 2800Å. Pt was patterned and further deposited as a counter electrode. When electricity was applied between In ₂ O ₃ and Pt at a voltage of 15 V for 0.1 seconds using In ₂ O ₃ as a cathode, interference color development was observed. 30 by measuring the viewing eye from the normal to the substrate.
When the film was fixed at a certain angle within 100°, the film thickness was observed as red, grass green, purple, colorless, etc. Where electricity was applied with the opposite polarity to the previous one,
The color disappeared within 0.1 seconds. At this time, the current used for color development and decolorization was 10 mA or less.

Example 2 SnO ₂ was applied to a glass substrate treated in the same manner as in Example 1.
Attach a Nesa electrode of _5200Å on top of the
Electron beam deposition was performed to film thicknesses of 4800 Å, 3900 Å, and 3700 Å, and an Al electrode was further patterned and deposited.

Through the same energization and observation as in Example 1, interference colors of red, magenta, grass green, and red were observed, respectively. The repetition of reverse polarity decoloring, coloring, and decoloring, and coloring memory were also satisfactory.

Example 3 BaTiO ₃ was applied to the same Nesa electrode substrate as in Example 1.
Perform electron beam evaporation of ZrO ₂ and SrTiO ₃ ,
When experiments were conducted using various combinations of counter electrodes such as NiCrSn, interference color display was observed in each case, and various color changes were observed as the position (angle) of the observing eye changed.

The present invention has been explained above, but the reactions to these displays are diverse, including various displays by patterning electrodes, displays by matrix electrodes, and optical images by combining with other properties, such as optical semiconductors. There are various ways of displaying, but the present invention extends to a display method that electrochemically causes interference colors, and is not limited to only the illustrated examples and examples.

[Brief explanation of the drawing]

1 and 2 are schematic diagrams illustrating the display method of the present invention. 1... Transparent substrate, 2... Transparent electrode layer, 3...
... layer containing a transition metal compound, 4 ... light-reflecting electrode layer, 5 ... power supply, 6 ... switch, 7 ... light source, 8, 8', 8'' ... observation eye.

Claims (1)

[Claims] 1. By applying current between the electrodes of an element comprising a pair of electrodes, one of which is transparent and the other is reflective, and in which a solid layer containing a transition metal compound is sandwiched between the pair of electrodes, the transparent A metal semi-transparent film layer is formed on a photosensitive electrode, and an interference color generated due to an optical path difference between light reflected from the metal semi-transparent film layer and light reflected from the light-reflective electrode is displayed. A display method characterized by: