Electronic Dimming Device

Abstract

To provide an electronic light-adjusting device capable of suppressing a decrease in response speed and color density during color-developing drive even when color-developing drive and color-decoloring drive are repeated. [Solution] An electrochromic element has a first electrochromic layer in which an oxidation reaction occurs, an electrolyte layer, and a second electrochromic layer in which a reduction reaction occurs, and at least one of the first electrochromic layer and the second electrochromic layer emits light due to the oxidation reaction or the reduction reaction; a voltage measurement unit that measures the open-circuit voltage of the electrochromic element; a color development drive that applies a voltage to the electrochromic element to cause it to develop color; and a voltage application unit that performs a refresh decolorization drive that drives the circuit of the electrochromic element until the open-circuit voltage measured by the voltage measurement unit drops below a predetermined value.

Description

[Technical Field]

[0001] The present invention relates to electronic dimming devices. [Background technology]

[0002] Patent Document 1 discloses an electrochromic element having a pair of substrates and an electrochromic medium disposed between them. When a voltage is applied to the electrodes provided on the pair of substrates, the transmittance of the compound in the electrochromic medium changes. This makes it possible to adjust the amount of light passing through the electrochromic element. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-167317 Summary of the Invention [Problem to be solved by the invention]

[0004] Such electrochromic elements may be driven to alternate between a colored state with reduced transmittance and a non-colored state with increased transmittance, which may cause a gradual decrease in response speed during coloring drive, making it impossible to achieve the target response speed.

[0005] An object of the present invention is to provide an electronic light control device that can suppress a decrease in response speed and color density during color driving, even when color driving and color erasing driving are repeated. [Means for solving the problem]

[0006] These objects can be achieved by the present invention as set forth in (1) to (7) below. (1) An electrochromic element having a first electrochromic layer in which an oxidation reaction occurs, an electrolyte layer, and a second electrochromic layer in which a reduction reaction occurs, wherein at least one of the first electrochromic layer and the second electrochromic layer emits light due to the oxidation reaction or the reduction reaction; a voltage measuring unit for measuring an open-circuit voltage of the electrochromic element; An electronic dimming device comprising: a coloring drive that applies a voltage to the electrochromic element to cause it to develop color; and a voltage application unit that performs refresh decoloring drive that drives the circuit of the electrochromic element until the open-circuit voltage measured by the voltage measurement unit drops below a predetermined value.

[0007] (2) The voltage application unit Stopping the application of voltage to the electrochromic element; and Short circuit the electrochromic element Rutsu Normal erasing drive stomach, In the refresh bleaching drive, the application of a voltage to the electrochromic element is stopped and the circuit of the electrochromic element is short-circuited, The time for which the circuit of the electrochromic element is short-circuited in the normal bleaching drive is shorter than the time for which the circuit of the electrochromic element is short-circuited in the refresh bleaching drive. The electronic dimming device according to (1) above.

[0008] (3) The electronic light control device according to (2), wherein the refresh bleaching drive causes the open circuit voltage measured thereafter to be lower than the open circuit voltage measured after the normal bleaching drive.

[0009] (4) The electronic dimming device according to (2) or (3), wherein the voltage application unit performs the refresh bleaching drive when the open-circuit voltage measured after the normal bleaching drive becomes equal to or greater than a threshold value.

[0010] (5) The voltage application unit is configured to repeatedly perform the coloring drive and the normal decoloring drive, The electronic light control device according to (2) or (3), wherein the voltage application unit performs the refresh bleaching drive when the number of repetitions of the coloring drive and the normal bleaching drive reaches a predetermined number or more.

[0011] (6) An electronic dimming device according to any one of (1) to (5) above, wherein the voltage application unit performs a reverse voltage application drive in which, prior to the refresh decolorization drive, a voltage of the opposite polarity to the voltage applied in the coloring drive is applied to the electrochromic element for a time shorter than the time for which the circuit is driven in the refresh decolorization drive.

[0012] (7) The electronic light control device according to any one of (1) to (6) above, which is used as glasses. [Effects of the Invention]

[0013] According to the present invention, an electronic light control device can be obtained that can suppress a decrease in response speed and color density during color driving, even when color driving and color-erasing driving are repeated. [Brief explanation of the drawings]

[0014] [Figure 1] 1 is a perspective view showing sunglasses (eyeglasses) to which the electronic light adjusting device according to the first embodiment is applied. [Figure 2] FIG. 2 is a perspective view of a first lens shown in FIG. [Figure 3] FIG. 3 is a cross-sectional view of the first lens shown in FIG. [Figure 4] FIG. 4 is a partially enlarged view of the EC function unit shown in FIG. 3. [Figure 5] FIG. 2 is a functional block diagram of a control unit shown in FIG. [Figure 6] 10 is a graph showing an example of the voltage applied to the first electrochromic element during the coloring drive period, and the change in voltage measured at the first electrochromic element during the coloring maintenance period, normal bleaching period, and refresh bleaching period. [Figure 7] 7 is a graph showing changes in transmittance of the first electrochromic element during a coloring drive period, a coloring maintenance period, and a normal decoloring period shown in FIG. 6. [Figure 8]A graph showing an example of the voltage applied to the first electrochromic element during the coloring drive period of the electronic dimming device of the second embodiment, and the change in voltage measured at the first electrochromic element during the coloring retention period, normal bleaching period, and refresh bleaching period. [Figure 9] 10 is a graph showing an example of the voltage applied to the first electrochromic element in the electronic dimming device according to the third embodiment, and the change in voltage measured at the first electrochromic element during the color retention period and the refresh bleaching period. DETAILED DESCRIPTION OF THE INVENTION

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An electronic light control device according to the present invention will be described in detail below with reference to preferred embodiments shown in the accompanying drawings.

[0016] First Embodiment 1. Configuration of the electronic light control device according to the first embodiment FIG. 1 is a perspective view showing sunglasses 100 (eyeglasses) to which the electronic light adjusting device according to the first embodiment is applied.

[0017] The sunglasses 100 shown in Fig. 1 include a frame 20, a first lens 31, a second lens 32, and a control unit 40. In the following description, when the sunglasses 100 are worn on the head of a user, the user side of the first lens 31 and the second lens 32 is referred to as the "back" and the opposite side is referred to as the "front." In the following description, the term "lens" includes not only optical elements that have the function of focusing or diverging light, but also optical elements that simply have the function of transmitting light.

[0018] Frame The frame 20 shown in FIG. 1 has two rim portions 21, 21, a bridge portion 22, two temple portions 23, 23, and two nose pad portions 24, 24.

[0019] The frame 20 is worn on the user's head, and the first lens 31 and the second lens 32 are positioned near the user's eyes.

[0020] Each rim portion 21 is ring-shaped. A first lens 31 is fitted inside one rim portion 21, and a second lens 32 is fitted inside the other rim portion 21.

[0021] The bridge portion 22 is rod-shaped and connects the rim portions 21 together. Each temple portion 23 is shaped like a temple, with one end connected to each rim portion 21 and the other end being a free end.

[0022] In addition, a control unit 40 is provided on the temple portion 23. The control unit 40 applies voltage to the first lens 31 and the second lens 32 to control their operation.

[0023] The nose pad portion 24 is provided on the edge of each rim portion 21 and is supported on the nose of the user of the sunglasses 100.

[0024] The constituent material of the frame 20 is not particularly limited, but examples thereof include various metal materials, various resin materials, etc. Also, it may be a composite material containing these materials.

[0025] The shape of the frame 20 is not limited to the shape shown in the drawings, as long as it can be worn on the user's head. For example, the rim portion 21 and the temple portion 23 may be omitted. Furthermore, the entire frame 20 may be omitted, and the first lens 31 and the second lens 32 may be used separately.

[0026] Furthermore, the electronic light adjusting device according to the present invention may be applied to eyeglasses other than sunglasses, such as prescription eyeglasses, fashion eyeglasses, goggles, etc. Furthermore, the electronic light adjusting device according to the present invention may be provided with one or more additional lenses similar to the first lens 31 and the second lens 32.

[0027] 1.2. First and second lenses Next, the first lens 31 and the second lens 32 will be described.

[0028] 1, the first lens 31 has a first electrochromic element 1. The second lens 32 has a second electrochromic element 2 that is separate from the first electrochromic element 1. The configurations of the second lens 32 and the second electrochromic element 2 are similar to the configurations of the first lens 31 and the first electrochromic element 1, and therefore will not be described.

[0029] FIG. 2 is a perspective view of the first lens 31 shown in FIG. The first lens 31 shown in FIG. 2 has a first electrochromic element 1 and a resin layer 35 provided on the rear surface thereof.

[0030] The first electrochromic element 1 is optically transparent and has the function of developing color when a voltage is applied. Furthermore, by switching the state of applied voltage, it is possible to reversibly switch between color development and decolorization. The power required for the operation of the first electrochromic element 1 is supplied from a control unit 40. The control unit 40 is also responsible for switching the state of applied voltage.

[0031] For example, when the sunglasses 100 are used, the amount of light passing through the first lens 31 (transmittance) can be controlled by switching the coloring and decoloring of the first electrochromic element 1 or by changing the coloring density.

[0032] FIG. 3 is a cross-sectional view of the first lens 31 shown in FIG. The first electrochromic element 1 shown in Figure 3 includes a first substrate 11, a second substrate 12, a first electrode 13, a second electrode 14, an EC functional part 60, a sealing part 55, a first auxiliary electrode 15, and a second auxiliary electrode 16.

[0033] 1.2.1. First board The first substrate 11 supports other components such as the EC function section 60. The first substrate 11 also serves as the outermost layer of the first electrochromic element 1, protecting the EC function section 60 and the like.

[0034] The material for forming the first substrate 11 is not particularly limited as long as it is a transparent resin material, but a material containing a transparent resin with thermoplastic properties is preferred.

[0035] The transparent resin is not particularly limited, but examples thereof include acrylic resins, polystyrene resins, polyethylene resins, polypropylene resins, polyester resins (such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN)), polycarbonate resins, polyamide resins, cycloolefin resins, vinyl chloride resins, and polyacetal resins, and a mixture of one or more of these resins is used. Among these, the transparent resin is preferably a polycarbonate resin or a polyamide resin, and more preferably a polycarbonate resin. These resins have excellent transparency (translucency) and mechanical properties, as well as excellent heat resistance and moldability. This can improve the transparency and shape precision of the first substrate 11, as well as the impact resistance and heat resistance of the first substrate 11.

[0036] Furthermore, the polycarbonate resin is preferably an aromatic polycarbonate resin, which has an aromatic ring in the main chain and contributes to improving the mechanical strength of first substrate 11.

[0037] The first substrate 11 may contain various additives such as dyes, pigments, antioxidants, fillers, plasticizers, light stabilizers, ultraviolet absorbers, heat ray absorbers, and flame retardants, as needed.

[0038] The thickness of the first substrate 11 is preferably 0.1 mm to 10.0 mm, more preferably 0.3 mm to 5.0 mm. If the thickness of the first substrate 11 is within this range, the first electrochromic element 1 can be made thin while maintaining its mechanical strength.

[0039] 1.2.2. Second board The second substrate 12 is disposed opposite the first substrate 11 with the EC functional unit 60 interposed therebetween, and supports other components such as the EC functional unit 60. The second substrate 12 also serves as the outermost layer of the first electrochromic element 1, protecting the EC functional unit 60 and the like. In the following description, the space between the first substrate 11 and the second substrate 12 is also referred to as the "inside."

[0040] The material of the second substrate 12 is not particularly limited as long as it is a transparent material, but a material containing a transparent resin with thermoplasticity is preferable. The transparent resin is the same as the material of the first substrate 11.

[0041] The thickness of the second substrate 12 may be the same as the thickness of the first substrate 11, or may be different.

[0042] The thickness of the second substrate 12 is preferably 0.1 mm to 10.0 mm, more preferably 0.3 mm to 5.0 mm. If the thickness of the second substrate 12 is within this range, the first electrochromic element 1 can be made thin while maintaining its mechanical strength.

[0043] 1.2.3.EC Functional Department FIG. 4 is a partially enlarged view of the EC function unit 60 shown in FIG.

[0044] The EC functional unit 60 (electrochromic circuit) shown in Figure 4 has a first electrode 13 and a first electrochromic layer 63 stacked in sequence on the inside of a first substrate 11, a second electrode 14 and a second electrochromic layer 64 stacked in sequence on the inside of a second substrate 12, and an electrolyte layer 65 filled between the first electrochromic layer 63 and the second electrochromic layer 64.

[0045] The first electrode 13 and the second electrode 14 are electrically connected to the control unit 40. The control unit 40 controls the potentials of the first electrode 13 and the second electrode 14, and injects and extracts charges into and from the first electrochromic layer 63 and the second electrochromic layer 64. This allows the EC function unit 60 to perform coloring drive, retention drive, normal bleaching drive, and refresh bleaching drive.

[0046] The constituent materials of the first electrode 13 and the second electrode 14 are not particularly limited as long as they are transparent conductive materials, and examples thereof include oxides such as ITO (Indium Tin Oxide), FTO (F-doped Tin Oxide), ATO (Antimony Tin Oxide), IZO (Indium Zinc Oxide), In2O3, SnO2, Sb-containing SnO2, and Al-containing ZnO, as well as Au, Pt, Ag, Cu, and alloys containing these, and one or more of these may be used in combination.

[0047] The thickness of each of the first electrode 13 and the second electrode 14 is set appropriately depending on the required conductivity. For example, when ITO is used as the constituent material of each of the first electrode 13 and the second electrode 14, the thickness is preferably about 50 nm or more and 200 nm or less, and more preferably about 100 nm or more and 150 nm or less.

[0048] The first electrochromic layer 63 contains a material that develops color through an oxidation reaction. The material that develops color through an oxidation reaction is not particularly limited, but examples thereof include polymers obtained by polymerizing a composition containing a radically polymerizable compound having triarylamine, triarylamine derivatives such as triphenylamine, bisacridan compounds, Prussian blue complexes, benzidine, nickel oxide, and the like, and one or more of these may be used in combination.

[0049] An example of a Prussian blue-type complex is a material made of Fe(III)4[Fe(II)(CN)6]3.

[0050] Among these, a polymer obtained by polymerizing a composition containing a radically polymerizable compound having triarylamine is particularly preferably used, since it can be operated at a constant voltage, has excellent durability against repeated use, and can provide an electrochromic element with high contrast.

[0051] The composition containing the radical polymerizable compound having a triarylamine may contain a radical polymerizable compound other than the radical polymerizable compound having a triarylamine, and a polymer obtained by polymerizing such a composition may be composed of a crosslinked product in which these radical polymerizable compounds are crosslinked.

[0052] The thickness of the first electrochromic layer 63 is not particularly limited, but is preferably about 0.1 μm or more and 30 μm or less, and more preferably about 0.4 μm or more and 10 μm or less.

[0053] The second electrochromic layer 64 contains a material that develops color through a reduction reaction. The material that develops color through a reduction reaction is not particularly limited, but examples thereof include inorganic electrochromic compounds, organic electrochromic compounds, conductive polymers, etc., and one or more of these can be used in combination.

[0054] Examples of inorganic electrochromic compounds include tungsten oxide, molybdenum oxide, iridium oxide, and titanium oxide, with tungsten oxide being particularly preferred. Tungsten oxide has a low reduction potential, resulting in a low coloring / fading potential, and is also excellent in durability due to being an inorganic material.

[0055] Examples of organic electrochromic compounds include low molecular weight organic electrochromic compounds such as azobenzenes, anthraquinones, diarylethenes, dihydroprenes, dipyridines, styryls, styrylspiropyrans, spirooxazines, spirothiopyrans, thioindigo, tetrathiafulvalenes, terephthalic acid, triphenylmethanes, triphenylamines, naphthopyrans, viologens, pyrazolines, phenazines, phenylenediamines, phenoxazines, phenothiazines, phthalocyanines, fluorans, fulgides, benzopyrans, and metallocenes. Viologen compounds and dipyridine compounds are particularly preferred. These compounds have low color development / discoloration potentials and good color values.

[0056] Examples of viologen compounds include compounds described in Japanese Patent No. 3955641 and JP-A-2007-171781.

[0057] Examples of dipyridine compounds include compounds described in JP-A Nos. 2007-171781 and 2008-116718.

[0058] Examples of conductive polymers include polypyrrole, polythiophene, polyaniline, and derivatives thereof.

[0059] Furthermore, it is preferable to use a material that develops color in the same tone as the material that develops color in the oxidation reaction described above as a material that develops color in the reduction reaction, which increases the maximum color density and, as a result, improves the contrast during color development.

[0060] On the other hand, when a material that develops color by an oxidation reaction and a material that develops color by a reduction reaction, which have different color tones, are used, it becomes possible to control the color development by mixing colors.

[0061] In addition, either the first electrochromic layer 63 or the second electrochromic layer 64 may be set not to develop color, but by having both develop color, the color density can be increased. This makes it possible to reduce the driving voltage applied to the EC function section 60 and improve the durability of the first electrochromic element 1 as the color development operation is repeated.

[0062] The thickness of the second electrochromic layer 64 is not particularly limited, but is preferably about 0.2 μm or more and 5.0 μm or less, and more preferably about 1.0 μm or more and 4.0 μm or less.

[0063] The electrolyte layer 65 is filled between the first electrochromic layer 63 and the second electrochromic layer 64, and contains an electrolyte having ion conductivity.

[0064] The electrolyte is not particularly limited, but examples thereof include inorganic ion salts such as alkali metal salts and alkaline earth metal salts, quaternary ammonium salts, and supporting salts of acids and alkalis. Specific examples include LiClO4, LiBF4, LiAsF6, LiPF6, LiCF3SO3, LiCF3COO, KCl, NaClO3, NaCl, NaBF4, NaSCN, KBF4, Mg(ClO4)2, Mg(BF4)2, etc., and these may be used alone or in combination of two or more.

[0065] Ionic liquids can also be used as the electrolyte material. Among ionic liquids, organic ionic liquids are easy to handle because they remain liquid over a wide temperature range, including room temperature.

[0066] As the molecular structure of organic ionic liquids, examples of the cationic component include imidazole derivatives such as N,N-dimethylimidazole salt, N,N-methylethylimidazole salt, and N,N-methylpropylimidazole salt; pyridinium derivatives such as N,N-dimethylpyridinium salt and N,N-methylpropylpyridinium salt; and aliphatic quaternary ammonium salts such as trimethylpropylammonium salt, trimethylhexylammonium salt, and triethylhexylammonium salt. Furthermore, in consideration of stability in the atmosphere, it is preferable to use a fluorine-containing compound as the anionic component, such as BF4. - , CF3SO3 - , PF4 - , (CF3SO2)2N - , (SO2F)2N - etc.

[0067] Such an electrolyte material may be an ionic liquid containing any combination of cationic and anionic components.

[0068] The ionic liquid may be directly dissolved in any of the photopolymerizable monomer, oligomer, and liquid crystal material. If the ionic liquid has poor solubility in these materials, it may be dissolved in a small amount of solvent to obtain a solution, and then this solution may be mixed with any of the photopolymerizable monomer, oligomer, and liquid crystal material to dissolve the ionic liquid.

[0069] Examples of the solvent include propylene carbonate, acetonitrile, γ-butyrolactone, ethylene carbonate, sulfolane, dioxolane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,2-dimethoxyethane, 1,2-ethoxymethoxyethane, polyethylene glycol, alcohols, and the like, or mixed solvents containing two or more of these.

[0070] The electrolyte may be in the form of a low viscosity liquid, a gel, a solid, a polymer cross-linked type, or a liquid crystal dispersion type. Of these, the electrolyte is preferably in the form of a gel or a solid, which can improve the mechanical strength and reliability of the EC functional unit 60.

[0071] The thickness of the electrolyte layer 65 is not particularly limited, but is preferably set to about 10 μm or more and 100 μm or less, and more preferably about 20 μm or more and 80 μm or less.

[0072] Between the first electrode 13 and the second electrode 14, an intermediate layer such as an insulating porous layer or a protective layer may be provided as needed.

[0073] In this embodiment, the EC function section 60 has the first electrochromic layer 63 and the second electrochromic layer 64, but either one of these may be omitted.

[0074] 1.2.4.Sealing Part 3, the sealing portion 55 is disposed between the first substrate 11 and the second substrate 12, and defines a colored region 70. This allows the EC functional portion 60 to be encapsulated in the colored region 70. The first electrode 13 and the second electrode 14 shown in FIG. 3 extend beyond the sealing portion 55 to the outside of the colored region 70.

[0075] The constituent material of the sealing portion 55 is not particularly limited as long as it is an insulating material having transparency, and examples thereof include resin materials such as acrylic resin and epoxy resin, and inorganic oxides such as silicon oxide (SiO), silicon oxynitride (SiON), and aluminum oxide (AlO).

[0076] The thickness of the sealing portion 55 is adjusted depending on the thickness of the EC function portion 60, and is preferably, for example, about 20 μm to 100 μm, and more preferably about 40 μm to 80 μm.

[0077] 1.2.5.1st auxiliary electrode The first auxiliary electrode 15 is laminated on the first electrode 13, which extends to the outside of the colored region 70. The first auxiliary electrode 15 is made of a material having a higher conductivity than the first electrode 13. This improves the efficiency of controlling the potential of the first electrode 13.

[0078] The material of the first auxiliary electrode 15 is not particularly limited as long as it has a higher conductivity than the first electrode 13, but examples thereof include silver, aluminum, copper, chromium, molybdenum, etc., and one or a combination of two or more of these may be used. The first auxiliary electrode 15 may be provided as needed, and may be omitted.

[0079] 1.2.6.Second auxiliary electrode The second auxiliary electrode 16 is laminated on the second electrode 14, which extends to the outside of the colored region 70. The second auxiliary electrode 16 is made of a material having a higher conductivity than the second electrode 14. This improves the efficiency of controlling the potential of the second electrode 14.

[0080] The material of the second auxiliary electrode 16 is not particularly limited as long as it has a higher conductivity than the second electrode 14, but examples thereof include silver, aluminum, copper, chromium, molybdenum, etc., and one or more of these may be used in combination. The second auxiliary electrode 16 may be provided as needed, and may be omitted.

[0081] 1.3.Control Unit The control unit 40 is provided in the temple portion 23 and controls the operation of the first electrochromic element 1 and the second electrochromic element 2. The control unit 40 performs similar control on each of the first electrochromic element 1 and the second electrochromic element 2, so below, the control over the first electrochromic element 1 will be representatively described.

[0082] FIG. 5 is a functional block diagram of the control unit 40 shown in FIG. The control unit 40 controls the operation of the first electrochromic element 1 so as to selectively execute a first operation (see FIG. 6), which is a normal coloring operation that causes the first electrochromic element 1 to color and fade, and a second operation (see FIG. 6), which differs from the first operation only in the behavior during fade. The control unit 40 basically repeats the first operation, but also executes the second operation when triggered by a condition described below.

[0083] As will be described in detail later, as shown in FIG. 6, during the period in which the first operation is performed, a period in which a voltage is applied to the first electrochromic element 1 to change the color density is referred to as a "coloring drive period." When the coloring drive period ends, the application of voltage is stopped and the electrochromic circuit (circuit) provided in the first electrochromic element 1 is opened. In the following description, opening the electrochromic circuit may be referred to as "opening the element." Short-circuiting the electrochromic circuit may be referred to as "short-circuiting the element."

[0084] After the coloring drive period ends, the color density is maintained due to the memory effect of the first electrochromic element 1. This period is called the "coloring retention period." After that, if necessary, the coloring state is canceled and the element is decolored by short-circuiting the first electrochromic element 1. The decoloring period is called the "normal decoloring period."

[0085] In the second operation, after the coloring drive period and coloring retention period have passed in the same manner as in the first operation, the first electrochromic element 1 is short-circuited (driven) to perform refresh decoloring drive. The period during which this refresh decoloring drive is performed is called the "refresh decoloring period."

[0086] The control unit 40 shown in FIG. 5 has a voltage measurement unit 42, a voltage determination unit 44, and a voltage application unit 46 as functional units.

[0087] In the first and second operations, the voltage measurement unit 42 measures the open-circuit voltage of the first electrochromic element 1. These open-circuit voltages are voltages (open-circuit voltages) between the first electrode 13 and the second electrode 14 measured when the first electrochromic element 1 is open.

[0088] The voltage determination unit 44 determines the color-developing drive voltage to be applied to the first electrochromic element 1 and the application time thereof in the first and second operations.

[0089] The functions of voltage determination unit 44 are realized by hardware including, for example, a CPU, memory, and an interface. An example of such hardware is a microcomputer. The CPU is a central processing unit. Examples of memory include any non-volatile memory element (ROM), any volatile memory element (RAM), and a removable external memory element. Examples of interfaces include digital input / output ports such as a Universal Serial Bus (USB). The functions of voltage determination unit 44 are realized by the CPU executing a program that is pre-loaded in memory. Note that instead of or in addition to a method in which a CPU executes a program to realize the above functions, a method in which hardware such as an FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit) realizes the above functions may be used.

[0090] In the first and second operations, the voltage application section 46 applies the color-developing drive voltage determined by the voltage determination section 44 to the first electrochromic element 1 for a predetermined time.

[0091] The first operation is an operation in which coloring drive, hold drive, and normal decoloring drive are performed in this order. Hereinafter, the period in which coloring drive is performed will be referred to as the "coloring drive period," the period in which hold drive is performed will be referred to as the "coloring hold period," and the period in which normal decoloring drive is performed will be referred to as the "normal decoloring period."

[0092] The second operation is an operation in which the same coloring drive as above, the same retention drive as above, and the refresh decoloring drive are performed in this order. Hereinafter, the period during which the refresh decoloring drive is performed will be referred to as the "refresh decoloring period."

[0093] The color-developing drive and the sustaining drive in the second operation may have different conditions from those in the first operation.

[0094] The refresh bleaching drive shorts the circuit of the first electrochromic element 1 until the open circuit voltage measured by the voltage measurement unit 42 drops below a predetermined value. This condition will be described in detail later. Note that the refresh bleaching drive will be described in the case where the circuit of the first electrochromic element 1 is shorted, but the present invention is not limited to this, and a configuration in which a reverse voltage is applied to the circuit of the first electrochromic element 1 may also be used.

[0095] The voltage application unit 46 includes, for example, a DC power supply, a voltage converter, and a switch. The DC power supply generates a predetermined DC voltage and may be, for example, a primary battery, a secondary battery, or an external power supply. The voltage converter converts the DC voltage generated by the DC power supply into a target value. The voltage converter may also have the function of generating a pulse-width modulated voltage from the DC voltage and changing its duty ratio to bring the effective voltage closer to the target value. The switch switches the coloring drive period, coloring retention period, etc. in response to a user's operation.

[0096] 2. Operation of electronic dimming devices 2.1.First operation Next, we will explain the operation of the sunglasses 100. In the following explanation, we will also explain the operation of the first electrochromic element 1 as a representative example.

[0097] As described above, in the first operation, the color development drive, the maintenance drive, and the normal decolorization drive are executed, for example, in this order.

[0098] 6 is a graph showing an example of the voltage V applied to the first electrochromic element 1 during the coloring drive period T1, and the voltage V measured at the first electrochromic element 1 during the coloring maintenance period T2, the normal bleaching period T3, and the refresh bleaching period T4. The horizontal axis of FIG. 6 represents time, and the vertical axis represents voltage.

[0099] Fig. 7 is a graph showing the change in transmittance of the first electrochromic element 1 during the coloring drive period T1, the coloring retention period T2, the normal bleaching period T3, and the refresh bleaching period T4 shown in Fig. 6. The horizontal axis of Fig. 7 represents time, and the vertical axis represents transmittance.

[0100] During the color-producing drive period T1 shown in Fig. 6, a voltage V is applied to the first electrochromic element 1. This causes charge to be injected into the first electrochromic element 1, increasing the color density. As a result, as shown in Fig. 7, color-producing drive is performed in which the transmittance gradually decreases during the color-producing drive period T1.

[0101] 6, after the coloring drive period T1 ends, the first electrochromic element 1 is opened, which causes a transition to the coloring maintenance period T2.

[0102] 7, immediately after the start of the coloring retention period T2, the transmittance (transmittance TR) immediately after the end of the coloring drive period T1 is maintained due to the memory effect. This allows coloring retention drive to be performed, which maintains the transmittance without consuming power.

[0103] In the example shown in Fig. 6, after the coloring retention period T2 ends, the first electrochromic element 1 is short-circuited, which causes a transition to the normal bleaching period T3. During the normal bleaching period T3, the application of voltage is stopped, causing the color density to decrease, and normal bleaching driving is performed, in which the transmittance increases, as shown in Fig. 7.

[0104] The above-described coloring drive, coloring maintenance drive, and normal color-eliminating drive are the basic operations of the sunglasses 100.

[0105] The period during which the normal bleaching drive is performed, i.e., the normal bleaching period T3, has a shorter period during which the circuit is shorted than the refresh bleaching period T4 described below. This shortens the time required for the normal bleaching drive, making it more convenient.

[0106] 2.2.Second operation Here, when the sunglasses 100 as an electronic photochromic device are used repeatedly, that is, when the first operation is repeated, there is a risk that the transmittance of the first electrochromic element 1 will not decrease sufficiently during the coloring drive period T1 or the coloring retention period T2. In this case, the density of the first electrochromic element 1 when it is coloring will be locally or overall low, and there is a risk that the functionality and design of the sunglasses 100 will be reduced. In particular, there is a concern about a decrease in response speed during coloring drive.

[0107] One of the causes of such a problem is a decrease in charge mobility that occurs with use of the sunglasses 100. When charge mobility decreases, it is thought that the injection and extraction of charge into and from the first electrochromic layer 63 is hindered, slowing down the rate at which the color density increases during color driving.

[0108] Therefore, in the second operation, as described above, the color development driving and the maintenance driving are performed, and then the refresh decoloring driving is executed.

[0109] During the refresh bleaching period shown in FIG. 6, the first electrochromic element 1 is kept short-circuited until the open-circuit voltage measured by the voltage measurement unit 42 drops below a predetermined value. This allows the charge injected into the first electrochromic layer 63 to be sufficiently removed (extracted), preventing or suppressing the above-mentioned problems. This prevents an unintended decrease in color density during coloring drive (an unintended increase in luminous transmittance during coloring) and also prevents a decrease in response speed during coloring drive. As a result, the sunglasses 100 can be made more durable during repeated coloring operations (ensuring sufficient response speed during coloring drive).

[0110] The "predetermined value" is an open-circuit voltage value at which the charge can be considered to have been released to such an extent that the occurrence of the above-mentioned problems can be sufficiently suppressed, and can be determined in advance by experiment, for example.

[0111] Furthermore, it is preferable that the voltage application unit 46 performs the refresh bleaching drive so that the open-circuit voltage VR measured after the refresh bleaching drive is lower than the open-circuit voltage VN measured after the normal bleaching drive, thereby more effectively removing the charge injected into the first electrochromic layer 63 and more effectively increasing the durability of the coloring operation to repeated cycles.

[0112] The ratio VR / VN of the open circuit voltage VR to the open circuit voltage VN is not particularly limited, but is preferably 0.05 or more and 0.95 or less, more preferably 0.1 or more and 0.9 or less, and even more preferably 0.2 or more and 0.8 or less.

[0113] This increases the probability that charges that could not be sufficiently extracted by the normal color-eliminating driving can be extracted by the refresh color-eliminating driving, so that the above-mentioned effect can be more reliably achieved.

[0114] If the ratio VR / VN is too large, the effect of performing refresh bleaching driving tends to be reduced, whereas if the ratio VR / VN is too small, the amount of charge injected into the first electrochromic layer 63 remaining after performing normal bleaching driving tends to increase, gradually decreasing the response speed.

[0115] The open-circuit voltage VN here is a threshold value at which refresh bleaching is required, and when this value is exceeded, refresh bleaching is performed. The specific value of the open-circuit voltage VN is not particularly limited, but is approximately 1.2 to 5.0 times the open-circuit voltage measured after normal bleaching of an unused first electrochromic element 1.

[0116] The refresh bleaching period T4 during which the refresh bleaching drive is performed is preferably longer than the normal bleaching period T3, which allows the charge injected into the first electrochromic layer 63 to be more effectively removed, thereby more effectively increasing the durability of the coloring operation to repeated cycles.

[0117] The ratio T4 / T3 of the normal bleaching period T3 to the refresh bleaching period T4 is not particularly limited, but is preferably 1.1 or more and 2160 or less, and more preferably 1.5 or more and 450 or less, thereby making it possible to more reliably exhibit the above-mentioned effects.

[0118] If the ratio T4 / T3 is too large, the refresh decoloring period T4 becomes relatively long, and it tends to take a long time before the next first operation becomes possible. In this case, convenience may be reduced. Also, if the ratio T4 / T3 is too large, the normal decoloring period T3 becomes relatively short, and decoloring after the first operation tends to be insufficient. In this case, the refresh decoloring drive will be performed more frequently, and as a result, convenience may be reduced.

[0119] Moreover, if the ratio T4 / T3 is too small, the refresh bleaching period T4 becomes relatively short, and the effect of the present invention may become insufficient.

[0120] The ratio T4 / T3 does not have to be within the above numerical range. That is, as long as the open-circuit voltage is reduced to a predetermined value or less during refresh bleaching drive, the normal bleaching period T3 and the refresh bleaching period T4 may be the same length, or the refresh bleaching period T4 may be shorter than the normal bleaching period T3.

[0121] The normal decolorization period T3 is not particularly limited, but is preferably 20 seconds or more and 100 seconds or less, and more preferably 40 seconds or more and 80 seconds or less.

[0122] The refresh decoloring period T4 is not particularly limited, but is preferably 110 seconds or more and 12 hours or less, and more preferably 120 seconds or more and 5 hours or less.

[0123] Furthermore, a particularly preferred combination is one in which the ratio VR / VN is 0.2 or more and 0.8 or less, and the ratio T4 / T3 is 1.5 or more and 450 or less, thereby enabling the above-mentioned effects to be more reliably and significantly exhibited due to a synergistic effect.

[0124] 2.3. Timing for Performing Second Operation (Timing for Performing Refresh Erasing Drive) In this embodiment, each time the first operation is completed, the circuit is opened and the voltage measurement unit 42 measures the open-circuit voltage. That is, after the first operation, a measurement period T5 is provided in which the voltage measurement unit 42 measures the open-circuit voltage. If the measured value is less than the threshold value, the first operation is performed next time, and when the measured value becomes equal to or greater than the threshold value, the second operation is performed.

[0125] The threshold value is a value at which it can be determined that if the charge injected into the first electrochromic layer 63 after the normal decoloring operation has not been sufficiently removed and the second operation is performed again in this state, an undesired increase in the luminous transmittance during color development will occur, and can be determined, for example, experimentally in advance.

[0126] In this way, by performing the second action as needed, the frequency with which the second action is performed can be reduced, and convenience can be improved.

[0127] After the refresh decoloring drive, another measurement period T5 may be provided, in which case it can be confirmed whether the refresh decoloring drive has been performed satisfactorily.

[0128] The timing for performing the refresh decoloring drive is not limited to the above, and may be, for example, performed immediately after the coloring drive or immediately after the normal decoloring drive.

[0129] 3. Effects of the First Embodiment The sunglasses 100 to which the electronic dimming device of the first embodiment is applied have a first electrochromic layer 63 in which an oxidation reaction occurs, an electrolyte layer 65, and a second electrochromic layer 64 in which a reduction reaction occurs, and are equipped with a first electrochromic element 1 and a second electrochromic element 2 as electrochromic elements in which at least one of the first electrochromic layer 63 and the second electrochromic layer 64 emits light through an oxidation reaction or a reduction reaction, a voltage measurement unit 42 that measures the open-circuit voltages of the first electrochromic element 1 and the second electrochromic element 2, respectively, and a voltage application unit 46 that performs a color development drive that applies a voltage to the first electrochromic element 1 and the second electrochromic element 2, respectively, to cause them to develop color, and a refresh bleaching drive that drives (in this embodiment, short-circuits) the circuits of the first electrochromic element 1 and the second electrochromic element 2, respectively, until the open-circuit voltage measured by the voltage measurement unit 42 drops below a predetermined value. By performing such refresh bleaching driving, it is possible to suppress an undesired decrease in color density during coloring driving of the first electrochromic element 1 and the second electrochromic element 2 (an undesired increase in luminous transmittance during coloring). Therefore, even when coloring driving and bleaching driving are repeated, it is possible to suppress a decrease in color density during coloring driving. In other words, it is possible to increase the durability of the sunglasses 100 against repeated coloring operations.

[0130] In this embodiment, the case where both the first electrochromic layer 63 and the second electrochromic layer 64 emit light has been described, but the present invention is not limited to this, and a configuration in which only one of the first electrochromic layer 63 and the second electrochromic layer 64 emits light may also be used.

[0131] Furthermore, the voltage application unit 46 performs normal bleaching drive, which requires a shorter time to short-circuit the circuits of the electrochromic elements, the first electrochromic element 1 and the second electrochromic element 2, than the refresh bleaching drive. This shortens the time required for normal bleaching drive, making it more convenient.

[0132] The refresh bleaching drive lowers the open-circuit voltage measured after the refresh bleaching drive compared to the open-circuit voltage measured after the normal bleaching drive. This more reliably prevents an unintended decrease in color density (unintended increase in luminous transmittance during color development) during color development drive of the first electrochromic element 1 and the second electrochromic element 2. This more effectively increases the durability of the sunglasses 100 against repeated color development.

[0133] The voltage application unit 46 performs refresh bleaching drive when the open circuit voltage measured after the normal bleaching drive reaches or exceeds the threshold value. In this way, by performing the second operation as needed, the frequency of performing the second operation can be reduced, thereby improving convenience.

[0134] Furthermore, the sunglasses 100 to which the electronic light control device according to the first embodiment is applied are used as spectacles. With this configuration, spectacles that are highly durable against repeated use can be realized.

[0135] Second Embodiment 4. Timing for performing the second operation in the electronic light control device according to the second embodiment Figure 8 is a graph showing an example of the voltage applied to the first electrochromic element during the coloring drive period T1 of the electronic dimming device of the second embodiment, as well as the change in voltage measured at the first electrochromic element during the coloring retention period, normal bleaching period, and refresh bleaching period.

[0136] The following description will focus on the differences from the first embodiment, and a description of the same points will be omitted.

[0137] In this embodiment, the control unit 40 counts the number of times the first operation has been performed, and when the number of times the first operation has been performed reaches a predetermined number, the control unit 40 performs the refresh decoloring operation. In other words, when the number of times that the coloring drive and the normal decoloring drive have been repeated reaches or exceeds a predetermined number, the control unit 40 performs the refresh decoloring drive.

[0138] The predetermined number of times is a value that can be used to determine whether the charge injected into the first electrochromic layer 63 after the normal decolorization drive has been sufficiently removed, and whether the next first operation will result in an undesired increase in the luminous transmittance during color development, and can be determined, for example, experimentally in advance.

[0139] In this way, by performing the second operation as needed, the frequency of performing the second operation can be reduced, thereby improving convenience. Furthermore, in this embodiment, the simple control of counting the number of repetitions is all that is required, so the control operation of the control unit 40 can be simplified.

[0140] When the predetermined number of times is n, n is preferably 1 or more and 100 or less, and more preferably 5 or more and 50 or less. This makes it possible to suppress an unintended decrease in color density during color driving (an unintended increase in luminous transmittance during color development) while suppressing the frequency of performing the second operation.

[0141] The first and second embodiments may be combined. That is, a determination as to whether the number of repetitions of the coloring drive and the normal bleaching drive has reached a predetermined number and a determination as to whether the open-circuit voltage measured after the normal bleaching drive has reached a threshold value may be performed in parallel. In this case, the second operation may be performed if either of the determinations indicates that the second operation is necessary, or if both of the determinations indicate that the second operation is necessary.

[0142] 5. Effects of the Second Embodiment In the second embodiment, the voltage application unit 46 is configured to repeatedly perform coloring drive and normal decoloring drive, and when the number of times that the coloring drive and normal decoloring drive are repeated reaches a predetermined number, the voltage application unit 46 performs refresh decoloring drive. This allows the second operation to be performed as needed, reducing the frequency of the second operation and improving convenience. Furthermore, the control operation can be simplified.

[0143] Third Embodiment 6. Second Operation of the Electronic Dimming Device According to the Third Embodiment Figure 9 is a graph showing an example of the voltage applied to the first electrochromic element in the electronic dimming device of the third embodiment, and the change in voltage measured at the first electrochromic element during the color retention period and the refresh decolorization period.

[0144] The following description will focus on the differences from the first embodiment, and a description of the same points will be omitted.

[0145] In this embodiment, reverse voltage application drive is performed in the second operation. Specifically, the second operation includes coloring drive, coloring maintenance drive, reverse voltage application drive, and refresh decoloring drive. The coloring drive, coloring maintenance drive, reverse voltage application drive, and refresh decoloring drive are performed in this order. That is, the voltage application unit 46 performs reverse voltage application drive before refresh decoloring drive.

[0146] In the reverse voltage application drive, a voltage of the opposite polarity to the voltage applied in the coloring drive is applied to the first electrochromic element 1 and the second electrochromic element 2. In addition, the time during which the voltage is applied in the reverse voltage application drive (reverse voltage application period T6) is shorter than the time during which the circuit is short-circuited in the refresh bleaching drive (refresh bleaching period T4).

[0147] By performing this reverse voltage application drive by the voltage application unit 46, the charge injected into the first electrochromic layer 63 can be quickly extracted, thereby shortening the refresh bleaching period T4, and therefore increasing the durability of the sunglasses 100 against repeated color development operations.

[0148] The ratio T6 / T4 of the reverse voltage application period T6 to the refresh bleaching period T4 is not particularly limited, but is preferably 0.9 or less, and more preferably 0.1 or less, so that the above-mentioned effects can be more reliably achieved.

[0149] The reverse voltage application period T6 is not particularly limited, but is preferably 0.1 seconds or more and 20 seconds or less, and more preferably 0.2 seconds or more and 10 seconds or less, so that the above-mentioned effect can be more reliably achieved.

[0150] 7. Effects of the Third Embodiment In the third embodiment, the voltage application unit 46 performs reverse voltage application drive, which applies a voltage of the opposite polarity to the voltage applied in the coloring drive to the first electrochromic element 1 and the second electrochromic element 2 before the refresh coloring drive for a time shorter than the time for driving the circuit in the refresh coloring drive (short-circuiting in this embodiment). This shortens the refresh coloring period T4. This increases the durability of the sunglasses 100 against repeated coloring operations.

[0151] The first embodiment and the third embodiment may be combined, the second embodiment and the third embodiment may be combined, or the first embodiment, the second embodiment, and the third embodiment may be combined.

[0152] Although the electronic light control device of the present invention has been described above, the present invention is not limited to the above-described embodiments.

[0153] For example, the electronic dimming device of the present invention may have each part of each of the above embodiments replaced with any component having a similar function, or may have any component added to each of the above embodiments. [Explanation of symbols]

[0154] 1. First electrochromic element 2. Second electrochromic element 11 First board 12 Second board 13 1st electrode 14 2nd electrode 15 1st auxiliary electrode 16 2nd auxiliary electrode 20 frames 21 Rim 22 Bridge section 23 Temple 24 Nose pad section 31 First lens 32 Second lens 35 Resin layer 40 Control Unit 42 Voltage measurement section 44 Voltage determination unit 46 Voltage application section 55 Sealing part 60 EC function department 63 First electrochromic layer 64 Second electrochromic layer 65 Electrolyte layer 70 colored area 100 sunglasses T1 Color driving period T2 color retention period T3 Normal bleaching period T4 Refresh bleaching period T5 measurement period T6 Reverse voltage application period V Voltage

Claims

1. an electrochromic element having a first electrochromic layer in which an oxidation reaction occurs, an electrolyte layer, and a second electrochromic layer in which a reduction reaction occurs, wherein at least one of the first electrochromic layer and the second electrochromic layer emits light due to the oxidation reaction or the reduction reaction; a voltage measuring unit for measuring an open-circuit voltage of the electrochromic element; An electronic dimming device comprising: a coloring drive that applies a voltage to the electrochromic element to cause it to develop color; and a voltage application unit that performs refresh decoloring drive that drives the circuit of the electrochromic element until the open-circuit voltage measured by the voltage measurement unit drops below a predetermined value.

2. the voltage application unit stops applying a voltage to the electrochromic element and performs normal bleaching drive to short-circuit the circuit of the electrochromic element; In the refresh bleaching drive, the application of a voltage to the electrochromic element is stopped and the circuit of the electrochromic element is short-circuited, The electronic light-adjusting device according to claim 1 , wherein the time for which the circuit of the electrochromic element is short-circuited in the normal bleaching drive is shorter than the time for which the circuit of the electrochromic element is short-circuited in the refresh bleaching drive.

3. The electronic light control device according to claim 2 , wherein the refresh bleaching driving causes the open circuit voltage measured thereafter to be lower than the open circuit voltage measured after the normal bleaching driving.

4. The electronic light-adjusting device according to claim 2 or 3, wherein the voltage application unit performs the refresh bleaching drive when the open-circuit voltage measured after the normal bleaching drive becomes equal to or greater than a threshold value.

5. the voltage application unit is configured to repeatedly perform the color development drive and the normal decolorization drive, The electronic light-adjusting device according to claim 2 , wherein the voltage application unit performs the refresh bleaching drive when the number of repetitions of the coloring drive and the normal bleaching drive reaches a predetermined number or more.

6. The electronic dimming device according to any one of claims 1 to 3, wherein the voltage application unit performs a reverse voltage application drive in which, prior to the refresh decolorization drive, a voltage of opposite polarity to the voltage applied in the coloring drive is applied to the electrochromic element for a time shorter than the time for which the circuit is driven in the refresh decolorization drive.

7. The electronic light-adjusting device according to claim 1 , which is used as eyeglasses.

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