JPH0583732U - Electro-Magnetic Optical Device - Google Patents

Abstract

(57) [Summary] [Object] To provide an electro-magnetic optical device capable of controlling the amount of light transmitted to a panel. A magneto-optical device comprising a light valve having a dielectric interposed between a pair of transparent electrodes and a solar cell for applying a voltage between the transparent electrodes, wherein the dielectric is an inorganic titanium compound. The anisotropic titanium fine particles are dispersed and contained, and the light absorption coefficient of this inorganic titanium compound is 5 × 10 5.
³ / cm or more.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an electromagneto-optical device which transmits light in the daytime and blocks light in the nighttime.

[0002]

[Prior Art]

 2. Description of the Related Art Conventionally, electromagnetism optical devices have been used in fields such as window glass of buildings.

Such an electromagnetism optical device is configured to allow outside light to pass therethrough during the daytime and to block outside light during the nighttime. In the above-mentioned conventional electromagnetism optical device, the switching means for controlling the applied state of the voltage is provided.

[0004]

[Problems to be solved by the device]

 However, in such a conventional electro-magneto-optical device, it was not possible to automatically transmit and block light in response to the light and darkness of daytime and nighttime.

The present invention has been devised to correct the drawbacks of the conventional electromagnetism optical device.

[0006]

[Means for Solving the Problems]

That is, the present invention relates to an electro-magnetic optical device comprising a light valve having a dielectric material interposed between a pair of transparent electrodes and a solar cell for applying a voltage between the transparent electrodes, wherein the dielectric material is an inorganic material. This is an electromagneto-optical device in which anisotropic fine particles of a titanium compound are dispersedly contained, and the light absorption coefficient of the inorganic titanium compound is 5 × 10 ³ / cm or more.

The light absorption coefficient of the fine particles has a function as a factor for determining the light blocking efficiency when the light blocking area is constant, and the light valve function is improved as the light absorption coefficient is increased. Therefore, in the present invention, the light absorption coefficient of the inorganic titanium compound is set to 5 × 10 ³ / cm or more.

Further, the aspect ratio has a function as a factor that determines the light shielding area before and after the electric field is applied. That is, in the case of fine particles having a large aspect ratio, the light-shielding area before and after the application of an electric field is significantly different. Therefore, the anisotropic fine particles used in the light valve of the electro-magneto-optical device of the present invention have the general formula: TiOxNy (wherein 1.37 ≦ x + y ≦ 1.95, 0.15 ≦ y ≦ 0.92). ), And a titanium compound having an aspect anisotropy with an aspect ratio of 3.5 or more, or a compound represented by the general formula: TiOx (wherein 1.35 ≤ x ≤ 1.85) and having an aspect ratio of 5 or more. It is preferable to use a titanium compound having anisotropy.

Further, the fine particles to be used preferably have a major axis of 3 μm or less, and preferably, the wavelength of light or less, that is, 0.7 μm or less.

The TiOxNy fine particles can be obtained, for example, by previously placing a titanium compound having shape anisotropy in a furnace and reacting it in a nitrogen-containing atmosphere such as NH ₃ , hydrazine, or methylamine.

Examples of titanium compounds having shape anisotropy include titanium oxide and the general formula: M (II) TiO ₃ [wherein M (II) represents a divalent metal such as Ba, Pb, or Sr. ]] And the like.

Further, TiOx fine particles can be easily obtained by heating TiO ₂ fine particles having shape anisotropy and exposing them to plasma of a reducing gas such as H ₂ or CO.

The dispersion medium for dispersing the anisotropic fine particles has a high insulating property and a high weather resistance, and has a viscosity that allows Brownian motion of the fine particles to be moderate and in the dispersion medium of the fine particles. Any substance can be used as long as it has the effect of suppressing sedimentation, and among them, those having a viscosity in the range of 0.65 to 1000 CS are preferable. Further, considering that the operating temperature range of the light valve is in the range of about −20 to 80 ° C., it is preferable to use, for example, an organodimethylsiloxane liquid polymer as the dispersion medium. Further, the concentration of fine particles in the dispersion medium is preferably in the range of 1 to 10% by weight.

In the light valve used in the present invention, a transparent electrode is disposed between the insides of a pair of transparent plates, and a dielectric material containing anisotropic fine particles dispersed between the pair of transparent electrodes. Intervene. Examples of the transparent plate-like body with the transparent electrode include a general glass substrate having an indium tin oxide (ITO) film and a tin oxide (SnO ₂ ) film formed on the surface thereof, and a light-transmitting material. Other members such as a plastic substrate or a flexible plastic film can be applied.

As the solar cell, any of single crystal, polycrystal, amorphous, thin film and the like can be used, but the required voltage is preferably 20 V or more.

[0016]

[Action]

In the present invention, since the solar cell is used as a power source, the voltage is applied to the electrodes during the daytime and the voltage application to the electrodes is stopped during the nighttime. In this case, the anisotropic fine particles are made of an inorganic titanium compound, and the light absorption coefficient of this inorganic titanium compound is 5 × 10 ³ / cm or more. Therefore, the voltage applied between the transparent electrodes of the light valve is controlled. By changing the transparency of the light valve, the amount of light transmitted to the panel through the light valve can be adjusted.

[0017]

【Example】

 Hereinafter, the present invention will be described in detail based on embodiments.

FIG. 1 is a front view showing the appearance of the electro-magnetic optical device of the present invention. In the figure, in the electro-magnetic optical device 1, four panels 2 are connected to a solar battery 4 via a DC-AC converter 3.

As shown in FIG. 2, the panel 2 includes polydimethylsiloxane having fine particles of an inorganic titanium compound and bead-shaped spacers between glass substrates 7 and 8 having transparent electrodes 5 and 6 disposed on the inner surfaces thereof. A light valve 10 sandwiching a dielectric 9 obtained by mixing well is attached.

In the light valve 10, when no voltage is applied between the transparent electrodes 5 and 6, the fine particles of the inorganic titanium compound between the transparent electrodes 5 and 6 are randomly oriented due to Brownian motion, resulting in a multidirectional scattering state. And scatter light. Therefore, the panel 2 blocks the external light from the light valve 10 at night when no electromotive force is generated in the solar cell 4.

On the other hand, in a state in which the solar cell 4 has an electromotive force generated by sunlight, a voltage is applied between the transparent electrodes 5 and 6 of the light valve 10 to generate an electric field between the transparent electrodes 5 and 6. By the action, the fine particles of the inorganic titanium compound are oriented in the electric field direction. Therefore, external light can be transmitted without being blocked by the light valve 10 of the panel 2.

Example 1 500 mg of needle-shaped TiO ₂ particles having an average aspect ratio of 5.0 was placed in a stationary tube furnace, the pressure inside the furnace was evacuated to room temperature, and then nitrogen gas was supplied to the gas supply pipe. It was supplied from the inside to the furnace and the pressure inside the furnace was adjusted to atmospheric pressure. Then, preheating was performed under a normal pressure while supplying a nitrogen gas at a flow rate of 200 ml / min, and then the nitrogen gas was replaced with ammonia gas. Furthermore, the temperature inside the furnace was raised to 750 ° C. and kept at that temperature for 3 hours.

After that, the heating was stopped and the inside of the furnace was evacuated again to remove the ammonia gas. Further, the nitrogen gas was allowed to flow in the furnace and the exhaust was continued and cooled to room temperature to obtain TiOxNy fine particles having an average aspect ratio of 5.0 and a light absorption coefficient of 2.0 × 10 ⁴ / cm.

Next, 500 mg of the obtained TiOxNy fine particles were dispersed in 5 g of silicone oil having a viscosity of 20CS, and a very small amount of a bead-like spacer (average particle diameter 25 μm) was dispersed therein. The sandwiched cell was sandwiched between glass substrates with electrodes (area resistance of 200 Ω / □) to prepare a sandwich cell, and the light valve of the present invention was produced.

Using this light valve, the transmittance change spectrum was measured when no voltage was applied (OFF state) and when a voltage of AC 40 V × 60 Hz was applied (ON state). The result is shown in FIG. As is clear from the figure, strong absorption was obtained in the visible region (near 1000 to 1500 nm) in the off state. The visible light transmittance in the on / off state was calculated from this transmittance change spectrum, and a transmittance change width of about 36% was obtained. Moreover, when the voltage was changed from the on state to the off state, the time required for the TiOxN y fine particles to be randomly oriented was about 0.1 second.

Example 2 500 mg of needle-shaped TiO ₂ fine particles having an average aspect ratio of 10 were placed in a stationary tube furnace, the pressure in the furnace was evacuated at room temperature, and then nitrogen gas was supplied from the gas supply pipe to the furnace. It was supplied into the furnace and the pressure inside the furnace was adjusted to atmospheric pressure. Then, preheating was performed under a normal pressure while supplying a nitrogen gas at a flow rate of 200 ml / min, and then the nitrogen gas was replaced with hydrogen gas. Furthermore, the temperature inside the furnace was raised to 950 ° C. and held for 3 hours with the temperature kept constant.

After that, heating was stopped and the inside of the furnace was evacuated again to remove hydrogen gas. Further, exhausting was continued while flowing nitrogen gas into the furnace, and the mixture was cooled to room temperature to obtain TiO x fine particles having an average aspect ratio of 7.5 and a light absorption coefficient of 5.1 × 10 ³ / cm ³ .

Next, 500 mg of the TiOx fine particles obtained above was added to 5 g of polydimethylsiloxane, and agitated sufficiently to obtain a suspension state. A small amount of bead-shaped spacers (average particle size 25 μm) were dispersed in this, and this dielectric was sandwiched between two glass substrates with transparent electrodes (area resistivity 200 Ω / □) to form a sandwich cell. Was produced.

With respect to the light valve using the above TiOx fine particles, the transmission spectrum of the on-off state at a voltage of 40 V × 60 Hz was measured, and the visible light transmittance was calculated. As a result, a transmittance variation width of about 35% was obtained. It was Moreover, when the voltage was changed from the on state to the off state, the time required for the TiO x fine particles to be randomly oriented was about 0.1 second.

[0030]

[Effect of the device]

 In the electro-magneto-optical device of the present invention, by controlling the voltage applied between the pair of transparent electrodes of the light valve to change the transparency of the light valve, it is possible to automatically transmit and block light to the panel through the light valve. Can be done on a regular basis.

[Brief description of drawings]

FIG. 1 is a front view of an electro-magnetic device according to an embodiment of the present invention.

FIG. 2 is a sectional view of the light valve.

FIG. 3 Transmittance change spectrum

[Explanation of symbols]

 1 Electro-Magnetic Optical Device 2 Panel 3 DC-AC Converter 4 Solar Cell 5, 6 Transparent Electrode 7, 8 Glass Substrate 9 Dielectric 10 Light Valve

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masahiro Hirata 3-5-11 Doshomachi, Chuo-ku, Osaka-shi, Osaka Inside Nippon Sheet Glass Co., Ltd.

Claims (3)

[Scope of utility model registration request] 1. An electromagneto-optical device comprising a light valve having a dielectric interposed between a pair of transparent electrodes and a solar cell for applying a voltage between the transparent electrodes, wherein the dielectric is inorganic titanium. The compound contains anisotropic fine particles of a compound dispersed therein, and the inorganic titanium compound has a light absorption coefficient of 5
An electro-magnetic optical device having a density of × 10 ³ / cm or more. 2. The anisotropic fine particles have the general formula: TiOx.
Ny (wherein 1.37 ≦ x + y ≦ 1.95, 0.15 ≦
The electromagneto-optical device according to claim 1, which is a titanium compound represented by y ≦ 0.92 and having a shape anisotropy with an aspect ratio of 3.5 or more. 3. The anisotropic fine particles have the general formula: TiOx.
The electromagneto-optical device according to claim 1, which is a titanium compound represented by the formula (1.35 ≦ x ≦ 1.85) and having a shape anisotropy with an aspect ratio of 5 or more.