JPH1138455A - Device having variable optical characteristic - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain glass which enables the flexible adjustment of optical characteristics in particular by electrically controlling and driving specific plural systems in order to modulate the light transmission level and light diffusion level of the device in a way of not associating these levels with each other. SOLUTION: The one system having the variable transmittance/absorptance of an electrochromic or viologen type is combined particularly with the systems having the variable light diffusion of an optical valve or liquid crystals. The respective systems are electrically controlled and driven in order to modulate the light transmission level and light diffusion level in a way of not associating these levels with each other. For example, this device is provided with the glass. The liquid crystal system 2 is disposed above one of the both surfaces thereof with an adhering means 3 in the form of a double coated adhesive sheet embodying the adhesion by pressure in-between. The electrochromic system 4 of a type A is arranged on the other surface of the substrate by continuous deposition using cathode sputtering.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to devices, devices having variable optical properties, and more particularly to glasses having variable optical / energy properties. The present invention more precisely relates to glasses whose properties can be changed by the diffusion or transmission of electrical input, for example electromagnetic waves of certain wavelengths, in particular infrared or visible light.

[0002]

BACKGROUND OF THE INVENTION So-called "intelligent" glass,
That is, there is a rapidly increasing demand for glasses whose properties can be varied freely, especially taking into account various parameters which can be gradually varied. Therefore, it would be extremely useful to be able to control the sunlight that enters through the glass that is fitted outside the building, car or train to prevent the room or cabin from being overheated during strong sunlight. You will understand. Similarly, for example, in the case of glass employed as an internal partition between two rooms in a building or between two passenger compartments of a train or airplane, it would be useful to be able to control the degree of visibility through the glass. . Many other applications for such glasses also exist. For example, a road sign or a city sign that shows a message or design only intermittently, for example, to prevent dizziness of the driver by darkening when necessary, or to show better attention And a rearview mirror of a vehicle that can prevent glare caused by the vehicle. Transparent glass devices can also be mentioned as having sufficient diffusion to be employed as a projection screen.

[0003] The interest in such glasses justifies that many systems have already been studied. Thus, known systems which make it possible to modulate the light transmission or absorption of glass are described, in particular, as the viologen system, as described in U.S. Pat. No. 5,239,406 or EP-A-0612826. I have.

[0004] For the same purpose, so-called electrochromic
The system exists and briefly describes the principle of its operation, in a known manner, they comprise a layer of electrochromic material capable of reversibly and simultaneously injecting cations and electrons, and The oxidized state corresponding to the injected state is of a different color, one of the states exhibiting a higher light transmission than the other. The injection and anti-injection reactions are:
Controlled and driven by a suitable electrical input by a current or voltage generator. Electrochromic materials, usually based on tungsten oxide, must thus be placed in contact with an electron source such as a transparent conductive layer and a cation source such as an ion conducting electrolyte.

Furthermore, in order to guarantee at least 100 switchings, etc., the electrochromic layer is used in combination with a counter electrode which can also inject cations reversibly and symmetrically with respect to the electrochromic material layer,
It is known that, macroscopically, the electrolyte must look like a medium for simple cations.

[0006] The counter electrode must consist of a neutral color, or at least a transparent or weakly colored layer, when the electrochromic layer is in a bleached state. Since tungsten oxide is the electrochromic material of the cathode, that is, its color state corresponds to the most diminished state, an anodic electrochromic material such as nickel oxide or iridium oxide is generally employed for the counter electrode. Further, it has been proposed to employ a material that is optically neutral in an oxidation state such as cerium oxide or a conductive polymer (such as polyaniline) or navy blue.

A description of such a system is given, for example, in European patents EP-0338876, EP040408.
27, EP-0575207 and EP-062884
No. 9 is found. Currently, these systems can be divided into two categories depending on the type of electrolyte employed:

[0008] That is, the electrolytic solution is a European patent EP-0.
In the form of a polymer or gel, such as, for example, a proton conducting polymer, as described in US Pat.
No. 623, EP-0518754 or EP-0532
No. 408, wherein the electrolyte is lithium ion, or the electrolyte is an inorganic layer,
Ion conducting but electronically insulating, these are what are referred to as "all solid" electrochromic systems. "All solid" electrochromic
For a description of the system, reference can be made to French patent application FR-96 / 03799 filed on Mar. 27, 1996.

A viologen or electrochromic system deposited or associated with a transparent substrate consists of a glass whose light absorption and transmission (and energy propagation) can vary within a given range, which range is employed. It is specifically determined by the choice of the electrochromic materials and / or their thickness. However, this glass has certain limitations inherent in it. Thus, even if a feature allows it to achieve very low light transmission in the colored state, for example below 1% to the order of 0.1%, it cannot guarantee complete darkness. In other words, the light transmission level, despite all things, is located on the other side of the glass, especially when there is a strong light source on the side of the object, for example in the case of room light at night Its light transmission level is still too high to prevent the observer from identifying the object or person.

Therefore, to obtain this effect, electrochromic glass alone is not sufficient, and if necessary, the transparency of the glass is reduced as in a net curtain, or the glass is simply completely opaque. It may be necessary to add an external device, which is made invisible by doing so. However, these devices require maintenance, are subject to aging, and have the property of being unable to modulate.
Another type of "intelligent" glass consists of what is referred to by the term optical bulb. It is a thin film comprising a generally cross-linked polymer matrix in which microdroplets containing particles exhibiting a favorable orientation under the action of an electric or magnetic field are dispersed.

The thin film exhibits variable optical properties, especially as a function of the potential applied to the terminals of a conductive layer disposed on either side of the thin film, and as a function of the concentration and properties of the directional particles. Show. Thus, Patent No. WO-93 / 0
No. 9460 discloses an optical valve based on a thin film comprising a crosslinkable polyorganosilane matrix and directional inorganic or organic particles, more particularly light absorbing particles such as polyiodide particles. When a voltage is applied to the thin film, light blocking is much less than when no voltage is applied.

Glasses with similar operating principles are also known under the name liquid crystal glass. It is based on the use of a thin film disposed between two conductive layers and is a nematic, having a positive dielectric anisotropy, to a polymeric material in which liquid crystal droplets are distributed. Is based on When a voltage is applied to the film, the liquid crystal is oriented along the desired axis, thereby making it visible. Without voltage,
Since there is no crystal alignment, the film diffuses and prevents vision.

Examples of such thin films are, inter alia, EP 0 238 164 and US Pat.
No. 47, US Pat. No. 4,806,922 and US Pat.
No. 56. This type of film is 2
The product name is `` Priva Light (Priva Light) ''
-Lite) ".

[0014] Actually, "NCAP" (nematic, curvilinear, aligned phase) or "PDL"
Any device can be employed, including a liquid crystal known under the name "C" (Polymer Disperse Liquid Crystal). Patent WO-92 / 19
For example, a polymer containing a cholesteric liquid crystal as described in No. 695 can be employed.

[0015]

The glass itself has its limitations. Thus, while it is possible to actually obtain a variable light diffusion, it is not possible to sufficiently darken the room or cabin in which the glass is fitted. Dichroic to successfully modulate light transmittance
There is a solution that consists of adding a dye type dye to the film. However, two disadvantages remain. That is,
On the one hand, with these dyes, the films exhibit a certain instability, especially for ultraviolet radiation, which partially dissolves not only in the liquid crystal droplets, but also in the polymer, which results in a system The possibility of modulating the light transmittance of the light is limited. In addition, light diffusion and transmittance changes are closely dependent on each other, and only high or low light transmittance / diffusion states can be obtained.

It is an object of the present invention to fill a gap in various "intelligent" glass systems that currently exist, and in particular to provide a glass that can flexibly adjust various properties, especially optical properties.

[0017]

The subject of the present invention is a device having variable optical properties, which device relates to at least one system with variable transmission / absorption of the electrochromic or viologen type, It concerns at least one system with variable light diffusion, in particular of the optical valve type, or it concerns liquid crystals. These two systems are electrically controlled and driven to modulate the light transmission and light diffusion levels of the device in an unrelated manner. Systems with variable light diffusion preferably function to spread more when no power is supplied than when electrically powered, especially when not powered, which maximizes the spread.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The device according to the invention opens a new field of application of so-called "intelligent" glass, especially when in the form of glass. In fact, it allows the choice of two different optical properties. Each of the two systems it comprises may be operated separately or together (steere
d) It is known to have its power supply.

[0019] Optional viologen or electrochromic systems are disclosed in the above-mentioned patent EP-0338876.
It is particularly suitable for the types described in EP 0 408 427, EP 0 575 203 and EP 0628849. It is preferably H ⁺ , Li ⁺ ,
A transparent conductive layer which is a so-called cathodic electrochromic layer capable of reversibly injecting cations such as Na ⁺ or Ag ⁺ , an electrolyte layer and, optionally, a second so-called anode which is also capable of injecting cations reversibly; And finally a second conductive layer in the form of a stack of functional layers.

With respect to the nature of the conductive layer of the device, two alternatives are possible. Fluoride doped tin oxide S
or you can use a doped materials based on metal oxide was such as _n O _2, F or tin is either possible to use doped indium oxide ITO. Further, for example, a layer made of a metal or a metal alloy such as gold Au, silver Ag, or aluminum Al can be employed. Since the device generally has two conductive layers, they can both be metal, both based on doped oxygen, or one based on metal and the other based on doped oxygen.

In order to form the electrochromic material layer of the cathode, tungsten oxide WO ₃ , molybdenum oxide MoO ₃ , vanadium oxide V ₂ O ₅ , niobium oxide NbO ₅ , titanium oxide TiO ₂ , WO ₃ / Au or WO ₃ / Ag such as "cermet" material (especially in the form of metal and ceramic combination of the metal particles in the ceramic matrix), and material selected from the group comprising tungsten oxide and rhenium oxide WO ₃ / ReO ₃ or mixtures thereof You can choose. These materials are particularly suitable for the reversible implantation of lithium ions. If the device works with reversible proton injection, the same material can be employed, but in this case it is hydrated.

To form the electrochromic material of the anode, a material corresponding to the formula M _x A _Y U ₂ can be selected. Here, M is a transmission metal, and A is, for example,
The ions employed for reversible injection, such as alkali metals or protons, and U is a chalcogen such as oxygen or sulfur. This is especially true for the implantation of H ⁺ proton ions, IrO _x H _y , IrO _x H _y N _z , Ni
_{O x, NiO x H y,} NiO x H y N z, RhO x, C
o _x and it may be mixtures of compounds or compound belonging to the group containing MnO _x. In the case of reversible insertion of Li ^+, the choices made are LiNiO _x , LiMn ₂ O ₄ , Li
_x IrO _y , NiO _x , CeO _x , TiO _x , CeO _x
-TiO _x , RhO _x , CoO _x , CrO _x , and Mn
The selection is made by compounds belonging to the group containing O _x or by bonding of the compounds.

As for the choice of electrolyte material, there are actually two types of choices as described above. In the case of reversible cation injection, this layer may be a layer of an aqueous solution such as water to which sulfuric acid or phosphoric acid is added, or in the case of reversible injection of lithium ions, an anhydrous liquid layer such as propylene carbonate containing a lithium salt. It is. This layer also may be a gel or a polymer layer, in particular polyoxyethylene and solid solution type cation phosphate POE-H ₃ PO ₄ - conducting polymer (in this case, the polymer is simultaneously an electron insulator Or based on a polymer obtained by polymerization of two precursors containing two types of grafted trialkoxysilanes and a plasticizer containing at least one urea group.
Selected lithium ion conducting polymers are those based on ionomers or branched polyethienimines and lithium salts obtained by partial neutralization of polyacrylic acid. For details regarding the nature and synthesis of such polymer products, reference may be made to the patents mentioned in the introductory part of the present application.

However, it can also be an electrolyte, especially in the form of a solid material based on metal oxides.
According to another preferred form of the invention, the system is selected to include only a layer of solid material. In the present invention, a “solid material” is a material having solid mechanical properties, in particular, all essentially inorganic or organic materials, so-called partially inorganic and partially organic materials,
All materials that can be obtained by sol-gel precipitation from organic-inorganic precursors are meant. These thus provide a so-called "all-solid" system structure that offers a clear advantage in terms of ease of manufacture. In fact,
If the system includes an electrolyte in the form of a polymer without solid mechanical properties, the manufacturer is actually forced to manufacture two "half cells" in parallel. Each of these cells is composed of a carrier substrate, covered by a first electrically conductive layer and then covered by a second electrochromic active layer, and these half cells are then formed by injecting an electrolyte therebetween. You. An "all solid" structure simplifies its manufacture because both layers of the system can be deposited one after another on a single carrier substrate. Since a single carrier substrate is sufficient compared to a usual two, a combination of an electrochromic system and a carrier substrate can reduce the weight.

This weight saving is of great value here. This is because the device according to the invention also comprises a second active system with variable light diffusion, and it is therefore important to limit its capacity and weight. Moreover, it is formed by an ionically conductive material that can be reversibly implanted with ions, whether the electrolyte is "solid" or not, but whose oxidation state remains essentially constant. Layers can be included. This may in particular be a material having electrochromic properties, as described in the aforementioned patent FR-96 / 03799.

A system comprising a device having variable light transmission / absorption according to the present invention is therefore particularly "all solid".
In the case of a system, it is found as being located between two rigid substrates or on one rigid substrate. The rigid carrier substrate is preferably formed from glass, acrylic polymer, polycarbonate or some polyurethane.

As a system with variable light diffusion to be incorporated into the device according to the invention, it is advantageous to choose a so-called optical valve system or a system with a liquid crystal as described above. In the case of systems involving liquid crystals, the properties of the polymer matrix (matrix) and of the crystals are correctly chosen such that the normal index (ordinary refractive index) n ₀ of the crystals is equal to the index (refractive index) n _p of the polymer.

When referring to systems with optical valves or liquid crystals, both systems have the form of an "active" polymer film, which in the case of optical valves contains droplets of a suspension of dichroic particles. In the case of a system including a liquid crystal, the droplet includes a liquid crystal. In order to ensure its electrical supply, it is usually arranged between two conductive layers, in particular those which are transparent and of the type used for the electrochromic system.

Further, in the film having two conductive layers, a carrier substrate is usually formed on one surface, more preferably on each of the surfaces. The latter are usually transparent. This is chosen to be rigid or semi-rigid, for example made of glass, acrylic polymer of the polymethyl methacrylate PMMA type or polycarbonate PC. It is also formed of flexible, in particular polyethylene terephthalate PET, or based on some flexible polycarbonate. As a result, a flexible sheet shape that can be easily handled,
It is possible to have a structure of the type PET / ITO / "active" polymer / ITO / PET. The combination of (“active” polymer + conducting layer + at least one carrier substrate) is then, with the aid of at least one layer of an organic binding polymer of the polyvinyl butyral PVB or ethylene / vinyl acetate EVA type or some polyurethane PU. , At least one transparent and rigid substrate.

The mounting of the two systems on a common device, one with variable light transmission / absorption and the other with variable light diffusion, can be performed in different ways. Without any limitation being included, the present invention proposes four shapes to choose from. Each of these shapes has its own effect on the intended application. In a first alternative configuration, the two systems are integrally connected to one another, but are at a distance from each other, or at least are mounted so that they do not completely adhere to each other. As a result, one system is fixedly and permanently mounted in place, and the second system is attached to this system based on additional and removable fixing means such as fixing clips or acrylate derivatives. It is conceivable to join with the aid of a pressure bonding means, such as a glued adhesive. Once both systems are coupled, means are provided to ensure electrical connection of both systems. This alternative configuration has the advantage that in the event of accident damage, one system can be replaced with another new system without having to replace or disassemble the entire device.

In a second alternative configuration, the device according to the invention has a rigid substrate of the glass substrate type. On one side, an "all solid" electrochromic system is installed. Place the system with liquid crystal on top of the electrochromic system on the same side or on the opposite side. This stacking can also provide the system with the liquid crystal first on the same side and then the electrochromic system. The advantage of this configuration is that the device thus formed is compact, since only one substrate is required.

In a third alternative form, the device according to the invention comprises two rigid substrates of the glass substrate type. The first embodiment places two systems between the two substrates. In a second embodiment, one of the two systems is located between two substrates and the second is located on the outer surface of one of the substrates. Preferably, the electrochromic system is placed between the two substrates, and the system with liquid crystal is outside, or vice versa. In the latter, the most suitable electrochromic system is an "all solid" system. This third alternative configuration is advantageous in that it is possible to use all electrochromic systems, including layers that are not "all solid" or "solid."

In a fourth alternative, the device according to the invention comprises three rigid substrates of the glass substrate type. In this case, one system is located on the first and second substrates and the other system is located between the second and third substrates. The advantage of this alternative configuration is the stiffness resulting from the complete mechanical protection of the functional layers of the two systems.

If the system with variable light diffusion is a system with an optical valve or a liquid crystal, these may be mounted on a rigid substrate of the glass type or on a variable transmission system of the electrochromic type already deposited on the rigid substrate. To adhere, replenish the adhesive means between the two parts to be joined. This bonding means is an adhesive or a pressure-sensitive adhesive, in particular an organic polymer layer for assemblies of the acrylate derivative type or of the PVB, EVA or PU type.

Further, the above-described device according to the present invention comprises:
It is effectively provided as a laminated glass and / or a multi-layer glass with gas interposed between sheets. The following are examples of applications of the device according to the present invention. The device is used, in particular, as architectural glass, for automobiles and for all industrial or public transport vehicles, as railway glass or airplane glass.

This device is used as a glass material facing the outside of a room or a passenger compartment. In this case, the operation of the variable transmittance system is adjusted in such a way as to limit the energy input, in particular from sunlight, or to slightly screen the light incident thereon. In the case of an electrochromic system, it is further colored in proportion to trying to limit the amount of light and / or heat incident on the cabin or room,
Adjust visual and thermal comfort. The function of the light diffusion variable system is adjusted in parallel and in a complementary manner, for example, to allow the glass to be transparent and, on the contrary, to be completely diffused. Light diffusion level is typically 560
It is measured using turbidity, defined as the ratio of diffuse transmittance to total transmittance in nm.

The device according to the invention thus exhibits all the light transmission _TL and all the turbidity in the given range. For example, by choosing a high T _L and a high turbidity, the glass can gain a hiding function.
This allows privacy to be protected in the room or cabin. This makes it possible to avoid using a net-like curtain.

By choosing a combination of low T _L and high turbidity, the glass acquires the function of a window shutter. In fact, at night, such glasses are very effective when used in lit rooms or passenger compartments. Outside pedestrians can no longer see the interior of the room or cabin, which is practical both as architectural glass and as glass especially used in sleeper train cabins.

The device according to the invention is likewise used as a glass material for interior partitions or glass doors. In this case, the darkness with a sufficient level of turbidity allows for shielding / privacy between rooms or cabin compartments. It is important to emphasize that, if the two systems are separated from each other, such a result and such a flexible operation cannot be obtained. Only when they are used in combination does such a function become possible in a complementary manner, in fact beyond the limits inherent in each case. The device according to the invention is therefore, for example, between 1 and 60%, in particular 5 and 50%
Between, or for illuminant D ₆₅ 0.01 and 20%
It independently has a light transmission that can vary between 1 and 100% and in particular a turbidity that can vary between 6 and 99%.

The device according to the invention can likewise be used advantageously as so-called "sunlight" glass for buildings, in particular mounted at an angle from vertical or even on horizontal parts. In the present invention, "sunlight blocking"
The term implies the property of preventing the formation of "sunspots" in rooms with very inclined glass. The device according to the invention can be completely replaced by glass or simply attached to it. The device according to the invention also has a completely different application case. So this device is very effective,
It forms part of a screen for a rear projection, more particularly for a transmission-type rear projector. There are many applications of transmissive rear projection screens. Display window,
Advertising boards or information boards can in particular be mentioned. A preferred arrangement to be found is to place the projector on one side and a viewer on the other side. In the device functioning as a screen, the variable diffusion system is preferably located on the side of the projector, and the variable transmittance / absorbance system is located on the side of the viewer. The light beam emitted from the projector then passes through the screen, and the variable transmittance / absorptivity system absorbs a portion of the transmitted beam once, but absorbs the interfering light that is diffused and reflected off the screen twice. to enable. This interference light is generated from a viewer.

In view of the above, the combination of the variable transmission / absorptivity system and the variable diffusion system greatly enhances the quality of the projected image, especially by adjusting the absorption level of the screen as a function of ambient light, for example. It is possible to improve. Therefore, the image quality and visibility can be maintained even when this projection is performed entirely during the day. As is generally known, the degree of improvement in visibility is quantitatively measured by a contrast C defined by the following relationship.

C = (L _max + R _I ) / (L _min + R _L ) where L _min is the minimum luminance based on the black point, L _max is the maximum luminance based on the white point,
R _L is the ambient light reflected by the screen including diffuse reflection by the diffuse component of the screen. With this definition of contrast C, when the value of _RL decreases,
It is possible to further improve the contrast, and the device of the present invention finely changes the diffused portion of _RL , and thereby adjusts the contrast as much as possible without darkening the building where the projector is installed. It is understood that it is possible.

In the case of rear projections operating by reflection, ie when both the spectator and the projector are located on the same side of the screen, the advantages of using the device according to the invention as a screen are: In other words, in the transmittance / absorptivity variable system, when the screen is placed in front of a normal window frame, it is possible to reduce the transmission level of direct light passing through the screen by darkening the projecting building. is there. This advantage is smaller than in the case of transmissive rear projection. In this example, in order to make the image projected on the screen by reflection visible even during the entire day, it is preferred to be assisted by an electrochromic type variable transmittance / absorptivity system. This type of system allows a very low light transmission, for example of less than 0.1%, in order to achieve a complete shielding effect with respect to external light.

The invention further relates to a method of operating the device according to the invention. The method comprises combining and controlling the power supply to the variable transmittance system and the variable diffusion system to achieve the desired _TL and light diffusion level by manual or automatic control. You. A voltage or current generator is used to power a system having a variable T _{L of the} electrochromic type. For details, see, for example, E
P-408427, EP-475847, EP-5
No. 68457, EP-683419 or FR-27
28696 can be referred to.

To supply power to a variable diffusion system of the type having a liquid crystal, a suitable voltage, for example 110 V /
A generator of a 50 Hz AC sinusoidal signal is sufficient. Either or both of the two systems are therefore electrically controlled by automatic control with the aid of electronic and / or data processing means. This control is performed according to pre-configured instructions or servo controlled by parameters provided by appropriate sensors. This parameter is temperature, brightness, light transmittance or sunlight. In applications where the device of the invention is used as a rear projection screen, the ambient brightness is a relevant parameter. When used as exterior glass in buildings or automobiles, measurements of temperature, _TL levels or sunlight passing through the device are more relevant.

FIGS. 1 to 4 are very schematic and do not correspond to the proportions of the various devices shown, but merely to make them easier to understand. In particular, electrical connections known per se are not shown. The rigid substrate used in all the examples below is 4 mm clear silica-soda-lime glass. (They are also colored in the bulk and have different thicknesses, for example in the range of 3 and 6 mm.) In all of the following examples, the device of the present invention works in conjunction with a system comprising a liquid crystal in electrochromic Use the system. The system with the liquid crystals used is of the type shown in patents WO-90 / 03593, US-5206747 and EP-0409442.

This is a transparent polymer film in which fine droplets of a nematic liquid crystal are already dispersed, and constitutes a liquid crystal emulsion having a total thickness of 25 μm, and a thickness of 17 μm.
It is sandwiched between two polyethylene terephthalate (PET) sheets, each of which is covered with a transparent conductive layer of 5 μm and each formed of ITO of 100 ohms per unit area. The structure of the system with liquid crystal is thus: PET / ITO / liquid crystal emulsion / ITO / PE
T.

The liquid crystal has several refractive index: equal in two directions perpendicular to the axis of symmetry, "normal" refractive index n ₀
And the “extraordinary” refractive index n ₀ on the axis of symmetry. The polymer is usually selected to have a refractive index very close to the refractive index n ₀ . When no voltage is applied, the axes of the various droplets are not interconnected. Thus, at the boundary between each polymer and the droplet, the incident light is greatly refracted by the difference in the refractive index between the polymer and the randomly oriented droplet. Therefore, the light is diffused in all directions. Maximum voltage (1
When 10 V) is applied, the optical axes of the various droplets are arranged in the direction of the electric field, that is, in the direction perpendicular to the glass. Light incident essentially perpendicular to the glass then encounters a medium with a continuous index of refraction n _p equal to n ₀ and is no longer diffused. Intermediate turbidity states are achieved at voltage values of in particular from 0 to 110V.

The type of electrochromic system used, for that part, depends on the type of construction of the device, which is more evident in the description of the figures, but here the reversible H ⁺ ions Works in all cases with insertion. Included are electrochromic systems referred to below as system "A" which is an "all solid" system. In this system, the functional layers are stacked as follows: 300 nm, S
nO ₂ : Conductive layer formed of F, 380 nm, cathode electrochromic material layer formed of tungsten oxide, 18 nm, tantalum oxide hydrate Ta ₂ O _5.
an electrolyte twin layer formed of an nH ₂ O layer and a 200 nm tungsten oxide hydrate WO ₃ .nH ₂ O layer;
45 nm, anodic electrochromic material layer based on iridium oxide hydrate H _X IrO _Y (which is replaced by nickel oxide hydrate), 200 nm, ITO
The conductive layer formed by.

The system is colored by applying a potential difference of -1.6 V, and +0.6 V eliminates the coloring of the system. Alternatives to the above include the electrochromic system referred to below as system "B" using an electrolyte in the form of a polymer. In this system, the functional layers are laminated as follows (lamination according to patent EP-0628849):
300 nm, first conductive layer formed of SnO ₂ : F, 55 nm, first layer of anodic electrochromic material formed of iridium oxide hydrate, which is replaced by nickel oxide hydrate 70 nm tantalum oxide hydrate Ta ₂ O ₅ .H functioning as a protective layer
_X layer, 100 μm polyoxyethylene and POE phosphate
-H ₃ PO electrolyte layer formed by solid solution of _4, 350 nm
Second layer of cathodic electrochromic material based on tungsten oxide, 300 nm second SnO
₂ : F layer.

Each operates in the same voltage range. Each of the systems "A" and "B" is connected to a voltage generator by striped current leads located at opposite ends of the two conductive layers. These two electrochromic systems, as described, make it possible to scan a range of light transmission between approximately 5 and 60%.

If one wishes to achieve a perfect shielding effect (for the case of an application as a rear projection screen operating as transmissive, as described above), a very low transmission value, 0.1 % Or less, for example, 0.01 to 0.1%.
05% can be achieved by significantly increasing the thickness of the injection / drain layer of the functional stack. Therefore,
WO ₃ type cathode electrochromic material layer
00 nm or more, further 1000 nm or more, for example, 500 nm
It is possible to make the thickness between 1500 and 1500 nm.

Similarly, by using an iridium oxide hydrate layer of, for example, 100 nm or more, or even 200 nm or more, the thickness of the anode electrochromic material layer can be made particularly 100 to 300 nm. It is possible. In this way, a 1000 nm layer of WO ₃ and 2
When a “B” type system with a 00 nm H _X IrO _Y layer is used, the T _{L in the} colored state is approximately 0.01%.
Is achieved. On the other hand, in the absence of coloring, the maximum light transmittance that can be achieved is not very high, especially 20%
From the order of 30%. Example 1 This corresponds to the device shown in FIG. 1 and a glass 1 is provided. On one of the two sides, a liquid crystal system 2 is provided with an adhesive means 3 in the form of a double-sided adhesive sheet interposed therebetween, which secures the adhesion by pressure (particularly a calendaring type operation). An "A" type electrochromic system 4 is placed on the other side of the substrate by continuous deposition using cathode sputtering. Example 2 This corresponds to that shown in FIG. 2, again with one glass substrate 1. In this case, the liquid crystal system 2 also has "A"
Supported on an electrochromic system 4 of the type. Example 3 This corresponds to that shown in FIG. 3, in which there are two glass substrates 1, 10 between which the liquid crystal system 2
Are placed between two sheets of EVA or PU with a thickness of 0.76 mm. The “A” type electrochromic system comprises a PVB sheet 6 and a glass substrate 10.
Or on the outer surface of the substrate 10. More clearly, the two forms are indicated by reference numerals 4 and 4-1. Example 4 This corresponds to that shown in FIG. 4, in which the device according to the invention comprises three glass substrates 1, 10,
11 is included. Between the substrate 1 and the substrate 10, a liquid crystal system 2 is arranged between the PVB sheets 5, 6 having a thickness of 0.76 mm. Between the substrate 10 and the substrate 11,
An electrochromic system 4 of the "B" type is arranged. In particular, in this configuration, given the use of the device as an outward facing glass, the electrochromic system 4 is preferably inward, which is a type of radiation by the sun that affects its durability. , Especially from ultraviolet light, by the insertion of PVB sheets 5, 6 in which the UV screening agent is advantageously incorporated.

FIG. 5 is a graph produced from the results obtained from Example 4. In FIG. 5, the light transmission (expressed as a percentage according to issuer D ₆₅ ) on the horizontal axis, which is actually obtained with the glass of Example 4 and is represented by all points within the rectangle 15 (including the edges) The turbidity value is plotted as a function of the turbidity value on the ordinate (turbidity is the ratio of diffuse transmittance to light transmittance at 560 nm, expressed as a percentage). .

The glass according to the invention can bind a low _TL value associated with a high turbidity, which means that the frame surrounds an area where the glass can fulfill the function of a window shutter, for example. It corresponds to 15 upper left quadrants. In the area enclosed by the upper right quadrant, the glass has a high T _L value and a high turbidity, again fulfilling the “hiding” function.

The combination of low T _L and low turbidity can provide a glass that can be viewed in the case of intense sunlight while limiting the heating of a room or cabin.
Combining high turbidity with a variable T _L can provide a glass that can be employed as a diffusion back screen that can be applied as an ambient light function to optimize image quality.

By comparison, the same value of turbidity is plotted as a function of T _L for other types of “intelligent” glass. The type of laminated electrochromic glass, ie
For glass / electrochromic system "B" / glass / PVB glass, a straight segment 16 is obtained.

In practice, this is not completely 0%, but "rises" at 5% in the most colored state and scans _TL in the range of up to 60% in the most faded state. On the other hand, the glass is non-diffuse, regardless of its coloring state. The straight line 17 is obtained in the case of a so-called liquid crystal laminated glass, such as that marketed under the name "Priva-Lite" by Saint-Gobain-Bitrage. The turbidity of such glasses can vary between approximately 6% of the value higher than 95%. On the other hand, the change in T _L is minimal, with T _L values in the range of 3-4% near 70%.

The linear segments 18 are employed in laminated glass having "Private Light" type 8 liquid crystal, in which a 2% black dichroic die is mixed, and the density is reduced by the mass relative to the liquid crystal. Is based on Changes in _TL and turbidity are completely interdependent. -The straight segment 19 is the same as that of the patent WO-93 / 09460.
And in particular in the case of glasses with optical valves based on dichroic particles as described in Example 1 therein. Again, _TL and turbidity are limited to a narrower range,
These changes are clearly interdependent.

It is noted that the axes of the graph contain negative values, which, of course, have no physical reality but make the graph easier to read. From the description of the above example, the following conclusions can be drawn. -The device according to the invention can be very varied in form, depending, for example, on whether compactness (Example 1 or 2) or robustness (Example 4) is a priority.

If a liquid crystal system clamped between two PVB sheets is selected, a laminated glass is formed which is clamped between two glass substrates (Examples 3 or 4). ). From the comparison made in FIG. 5, it can be seen that only the device according to the invention is able to change the turbidity and T _L in an unrelated manner, in particular the currently available “intelligent”
A "pair" of T _L / turbidity, which cannot be achieved with glass, can be obtained.

[Brief description of the drawings]

FIG. 1 illustrates an example of an apparatus employing a single rigid substrate according to the present invention.

FIG. 2 illustrates another example of an apparatus employing a single rigid substrate according to the present invention.

FIG. 3 illustrates an apparatus employing two rigid substrates according to the present invention.

FIG. 4 illustrates an apparatus employing three rigid substrates according to the present invention.

FIG. 5 is a graph comparing _TL values with turbidity.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Glass substrate 2 ... Liquid crystal system 3 ... Adhesion means 4 ... Electrochromic system 4-1 ... Electrochromic system 5 ... Sheet 6 ... Sheet 10 ... Substrate 11 ... Substrate

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09K 9/02 C09K 9/02 A

Claims (22)

[Claims] 1. An apparatus having variable optical properties, in particular at least one system having a variable transmittance / absorption of electrochromic or viologen type (4).
In combination with at least one system (2), in particular with variable light diffusion or liquid crystal of an optical valve, each system modulating the light transmission and light diffusion levels of the device in a manner unrelated to each other, An apparatus having variable optical characteristics, which is controlled and driven in a controlled manner. 2. A system with variable transmission / absorption (4) is an electrochromic system comprising a stack of functional layers, said functional layers comprising a conductive layer and H ⁺ ,
A so-called cathodic electrochromic layer capable of reversibly implanting cations such as Li ⁺ , Na ⁺ and Ag ⁺ ;
2. The device with variable optical properties according to claim 1, comprising an electrolyte layer and optionally a so-called anodic second electrochromic layer and a second conductive layer, also capable of reversibly implanting cations. 3. The system with variable transmittance / absorption (4) is an electrochromic system comprising a stack of functional layers, said functional layers being in the form of an aqueous or anhydrous liquid or of a polymer or gel. 3. The device with variable optical properties according to claim 1 or 2, comprising an electrolyte material in form. 4. The system with variable transmission / absorption (4) is an electrochromic system with a stack of functional layers, said functional layers being in the form of solid materials, especially based on metal oxides. The device with variable optical properties according to claim 1 or 2, wherein the electrochromic system comprises only a layer of solid material. 5. A system with variable transmission / absorption (4) comprising a stack of functional layers arranged between two transparent rigid substrates (1, 10-10, 11), especially made of glass. The device with variable optical properties according to any one of claims 1 to 4, wherein the device has a variable optical property. 6. A system with variable transmission / absorption (4) is an electrochromic system comprising a stack of functional layers deposited on a single transparent rigid substrate (1), especially made of glass. Apparatus with variable optical properties according to any one of claims 1, 2 and 4. 7. The system with variable light diffusion (2) is a system with an optical valve or a liquid crystal, in particular comprising a film of a polymer with beads embedded in a liquid crystal, preferably of a crystal with a polymer index np. 7. The device with variable optical properties according to claim 1, wherein the device has an index np and is arranged between two conductive layers. 8. A polymer film of the optical valve type or a film having a liquid crystal between two conductive layers, on at least one side, in particular on both sides, of a transparent, rigid or relatively rigid type of glass. 8. A device with variable optical properties according to claim 7, comprising an acrylic polymer and some polycarbonate PC or a flexible type of polyethylene terephthalate PET or other polycarbonate. 9. A combination of an optical valve type polymer or a polymer film having a liquid crystal, a conductive layer thereof, and a carrier substrate thereof, comprising polyvinyl butyral P
Can be laminated to at least one transparent glass type rigid substrate by at least one layer of organic polymer combining VB, ethylene / vinyl acetate EVA, or some polyurethane PU types,
An apparatus having variable optical properties according to claim 8. 10. The system (4) with variable transmission / absorption and the system (2) with variable light diffusion are both held together but have a certain distance from each other. ,
An apparatus having variable optical properties according to any one of claims 1 to 9. 11. A solid substrate of a glass substrate type (1)
The substrate comprises an all-solid electrochromic system (4) comprising a stack of functional layers of solid material on one side, and a system (2) comprising a liquid crystal on the other side comprises an electrochromic system. 10. Any one of claims 1 to 9 superimposed on
An apparatus having the variable optical characteristics according to the paragraph. 12. The method according to claim 1, comprising two rigid substrates of the glass substrate type, between which the all-solid-state electrochromic system and the system with liquid crystal are arranged. An apparatus having variable optical properties according to any one of the preceding claims. 13. An electrochromic system (4) arranged between two substrates and a system (2) having a liquid crystal arranged on one outer surface of the two substrates, or 2
With liquid crystal arranged between two substrates and 2
11. A substrate according to any one of the preceding claims, comprising two rigid substrates (1, 10) of the glass substrate type having an all-solid electrochromic system disposed on one outer surface of one substrate. An apparatus having the described variable optical properties. 14. An electrochromic system (4) disposed between the first and second substrates (10, 11) and a liquid crystal disposed between the second and third substrates (1, 10). Of glass substrate type with system (2) having
Device with variable optical properties according to any of the preceding claims, comprising two rigid substrates (1, 10, 11). 15. System with variable light diffusion (2)
Are rigid substrates (1, 10) of glass type or bonding means, in particular pressure-sensitive adhesives or PV for sheets or assemblies.
A system comprising a liquid crystal adapted to be attached to an electrochromic system (4) having a variable transmission / absorption utilizing a B, PU or EVA organic polymer (5, 6). 15. An apparatus having variable optical characteristics according to any one of claims 14 to 14. 16. Variable optical properties according to claim 1, mounted as laminated glass and / or mounted as multiple glasses with gas sheets in between. apparatus. 17. The variable optical property according to claim 1, which is used as glass for industrial or public transport vehicles such as buildings, automobiles, trains, and airplanes. How to use the device. 18. The device with variable optical properties according to claim 17, which is used as an external glass or as a glass or a door glass for an internal partition, in particular to provide the function of a window shutter or the function of a blurring means. how to use. 19. The use of a device with variable optical properties according to claim 17, wherein the device is used as a sun-blocking glass for buildings, in particular as a glass which is tilted with respect to the vertical. 20. A back projector that operates as a reflection type to form part of a screen for a back projector, particularly a back projector that operates as a transmission type, or to darken the screen, to improve screen contrast. 17. Use of a device having variable optical properties according to any of the preceding claims, used to form part of a screen for use. 21. Supply of electricity to a system (4) with variable transmittance / absorptivity and supply of electricity to a system (2) with variable light diffusion using manual or automatic control. In order to obtain the light transmission and diffusion level of
17. A method of operating a device having variable optical properties according to any one of claims 1 to 16, which is jointly controlled. 22. Supply of electricity to the system (4) with variable transmission / absorption and / or supply of electricity to the system (2) with variable light diffusion is achieved by means of suitable sensors, in particular temperature, illumination, Performed by automatic control using electronic and / or data processing means, in response to pre-established or servo-controlled commands, by measurement of light transmittance, or parameters given by the measurement of sunlight; A method of operating a device having variable optical properties according to claim 21.