Electronic dimming device

Abstract

To provide an electronic dimming device that can increase the rate of change in color density while suppressing the degradation of the electrochromic element. [Solution] The electronic dimming device of the present invention comprises an electrochromic element whose transmittance changes when a voltage is applied, and a voltage application unit that performs color driving by applying a color pulse voltage to the electrochromic element in a first period, and applying a color drive voltage to the electrochromic element in a second period after the first period, thereby reducing the transmittance of the electrochromic element. The color pulse voltage is a higher voltage than the color drive voltage, and the application time of the color pulse voltage is shorter than the application time of the color drive voltage.

Description

Technical Field

[0001] The present invention relates to an electronic dimming device.

Background Art

[0002] Patent Document 1 discloses an electrochromic element having a pair of substrates and an electrochromic medium disposed therebetween. When a voltage is applied to electrodes provided on the pair of substrates, the transmittance of a compound in the electrochromic medium changes. Thereby, the amount of light passing through the electrochromic element can be adjusted.

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such an electrochromic element, when adjusting the amount of transmitted light (coloring density), it is necessary to apply a voltage for a long time. For this reason, there is a concern that the usability of the electrochromic element may decrease.

[0005] On the other hand, by increasing the applied voltage, the amount of transmitted light can be adjusted in a short time. However, in that case, there is a risk that the deterioration of the electrochromic element may be accelerated.

[0006] An object of the present invention is to provide an electronic dimming device that can increase the rate of change of coloring density while suppressing the deterioration of an electrochromic element.

Means for Solving the Problems

[0007] Such an object is achieved by the present invention described in the following (1) to (5). (1) An electrochromic element whose transmittance changes when a voltage is applied, A voltage application unit that performs color driving to reduce the transmittance of the electrochromic element by applying a color pulse voltage to the electrochromic element during the first period, and applying a color driving voltage to the electrochromic element during the second period after the first period, Equipped with, The aforementioned color-developing pulse voltage is a higher voltage than the aforementioned color-developing drive voltage. When the color-generating pulse voltage is denoted as VA and the color-generating drive voltage as VB, VA / VB is between 1.05 and 3.9. The color-developing pulse voltage is between 1.1V and 3.9V. The application time of the color-developing pulse voltage is shorter than the application time of the color-developing drive voltage. Ku, The voltage application unit applies the color pulse voltage multiple times during the color drive. An electronic dimming device characterized by the following features.

[0008] (2) The electronic dimming device according to (1) above, wherein the application time of the color-developing pulse voltage is the time for injecting an amount of charge equivalent to 1% to 50% of the amount of charge required for the electrochromic element to develop the maximum color intensity.

[0009] (3) The color pulse voltage is a voltage that is 0.1V or higher than the color drive voltage. The electronic dimming device according to (1) or (2) above, wherein the application time of the color-developing pulse voltage is 0.1 seconds or more and 15 seconds or less.

[0013] ( 4 The electrochromic element is The first electrochromic layer develops color through an oxidation reaction, Electrolyte layer, A second electrochromic layer that develops color through a reduction reaction, The above (1) to ( 3 An electronic dimming device as described in any of the following.

[0014] (5 ) The electrochromic device according to any one of the above (1) to 4 ).

Advantages of the Invention

[0015] According to the present invention, an electrochromic device capable of increasing the rate of change of coloring density while suppressing deterioration of the electrochromic element can be obtained.

Brief Description of the Drawings

[0016] [Figure 1] It is a perspective view showing sunglasses (glasses) to which the electrochromic device according to the first embodiment is applied. [Figure 2] It is a perspective view of the first lens shown in FIG. 1. [Figure 3] It is a cross-sectional view of the first lens shown in FIG. 2. [Figure 4] It is a partially enlarged view of the EC functional part shown in FIG. 3. [Figure 5] It is a functional block diagram of the control part shown in FIG. 1. [Figure 6] It is a graph showing an example of the voltage applied to the first electrochromic element during the coloring driving period, and the change in the voltage measured by the first electrochromic element during the holding driving period and the bleaching driving period. [Figure 7] It is a graph showing the change in the transmittance of the first electrochromic element during the coloring driving period, the holding driving period, and the bleaching driving period shown in FIG. 6. [Figure 8] It is a graph showing an example of the voltage applied to the first electrochromic element during the coloring driving period performed by the electrochromic device according to the second embodiment, and the change in the voltage measured by the first electrochromic element during the holding driving period and the bleaching driving period. [Figure 9] It is a graph showing the change in the transmittance of the first electrochromic element during the coloring driving period, the holding driving period, and the bleaching driving period shown in FIG. 8.

Modes for Carrying Out the Invention

[0017] The electronic dimming device according to the present invention will be described in detail below based on preferred embodiments shown in the accompanying drawings.

[0018] <First Embodiment> 1. Configuration of the electronic dimming device according to the first embodiment Figure 1 is a perspective view showing sunglasses 100 (eyeglasses) to which an electronic dimming device according to the first embodiment is applied.

[0019] The sunglasses 100 shown in Figure 1 comprises a frame 20, a first lens 31 and a second lens 32, and a control unit 40. In the following description, when the sunglasses 100 are worn on the user's head, the user-facing side of the first lens 31 and the second lens 32 is referred to as the "back," and the opposite side as the "front." Furthermore, in the following description, "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.

[0020] 1.1. Frame The frame 20 shown in Figure 1 has two rim sections 21, 21, a bridge section 22, two temple sections 23, 23, and two nose pad sections 24, 24.

[0021] The frame 20 is attached to the user's head, and the first lens 31 and the second lens 32 are positioned near the user's eyes.

[0022] 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. The bridge section 22 is rod-shaped and connects the rim sections 21 together.

[0023] Each temple portion 23 is shaped like a lisp, with one end connected to each rim portion 21 and the other end being a free end.

[0024] Furthermore, a control unit 40 is provided in the temple portion 23. The control unit 40 applies voltage to the first lens 31 and the second lens 32 and controls their operation.

[0025] The nose pad portion 24 is provided on the edge of each rim portion 21 and is supported by the nose of the wearer of the sunglasses 100.

[0026] The constituent materials of the frame 20 are not particularly limited, but examples include various metal materials, various resin materials, etc. Alternatively, composite materials containing these materials may also be used.

[0027] The shape of the frame 20 is not limited to the illustrated shape, 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. Alternatively, the entire frame 20 may be omitted, and the first lens 31 and the second lens 32 may be used individually.

[0028] Furthermore, the electronic dimming device according to the present invention may be applied to eyeglasses other than sunglasses, such as prescription glasses, fashion glasses, goggles, etc. Also, the electronic dimming device according to the present invention may have one or more additional lenses similar to the first lens 31 and the second lens 32.

[0029] 1.2. First lens and second lens Next, the first lens 31 and the second lens 32 will be described.

[0030] As shown in Figure 1, the first lens 31 has a first electrochromic element 1. The second lens 32 has a second electrochromic element 2, which is separate from the first electrochromic element 1. The configuration of the second lens 32 and the second electrochromic element 2 are the same as the configuration of the first lens 31 and the first electrochromic element 1, so their explanation is omitted.

[0031] Figure 2 is a perspective view of the first lens 31 shown in Figure 1. The first lens 31 shown in Figure 2 comprises a first electrochromic element 1 and a resin layer 35 made of hard resin provided on its back surface.

[0032] The first electrochromic element 1 is light-transmitting and has the function of emitting color when a voltage is applied. Furthermore, the color emission and decolorization can be reversibly switched by switching the voltage application state. The power required for the operation of the first electrochromic element 1 is supplied from the control unit 40. The control unit 40 is also responsible for switching the voltage application state.

[0033] For example, when the sunglasses 100 are used, the amount of light (transmittance) passing through the first lens 31 can be controlled by switching the color development or decolorization of the first electrochromic element 1, or by changing the color intensity.

[0034] Figure 3 is a cross-sectional view of the first lens 31 shown in Figure 2. The first electrochromic element 1 shown in Figure 3 comprises a first substrate 11, a second substrate 12, a first electrode 13, a second electrode 14, an EC function section 60, a sealing section 55, a first auxiliary electrode 15, and a second auxiliary electrode 16.

[0035] 1.2.1. First circuit board The first substrate 11 supports other components such as the EC function unit 60. Furthermore, the first substrate 11 forms the outermost layer of the first electrochromic element 1, protecting the EC function unit 60 and other components.

[0036] The constituent material of the first substrate 11 is not particularly limited as long as it is a transparent resin material, but a material containing a thermoplastic transparent resin is preferred.

[0037] The transparent resin is not particularly limited, but examples include acrylic resins, polystyrene resins, polyethylene resins, polypropylene resins, polyester resins (polyethylene terephthalate (PET), polyethylene naphthalate (PEN), etc.), polycarbonate resins, polyamide resins, cycloolefin resins, vinyl chloride resins, polyacetal resins, etc., and one or more of these can be used. Among these, the transparent resin is preferably a polycarbonate resin or a polyamide resin, and more preferably a polycarbonate resin. These have excellent transparency (light transmission) and mechanical strength, as well as excellent heat resistance and moldability. Therefore, the transparency and shape accuracy of the first substrate 11, as well as the impact resistance and heat resistance of the first substrate 11 can be improved.

[0038] Furthermore, the polycarbonate resin is preferably an aromatic polycarbonate resin. Aromatic polycarbonate resins have aromatic rings in their main chain, which contribute to improving the mechanical strength of the first substrate 11.

[0039] The first substrate 11 may optionally contain various additives such as dyes, pigments, antioxidants, fillers, plasticizers, light stabilizers, ultraviolet absorbers, heat absorbers, and flame retardants.

[0040] The thickness of the first substrate 11 is preferably 0.1 mm or more and 10.0 mm or less, and more preferably 0.3 mm or more and 5.0 mm or less. If the thickness of the first substrate 11 is within the above range, it is possible to achieve both thinness and mechanical strength of the first electrochromic element 1.

[0041] 1.2.2. Second board The second substrate 12 is positioned opposite the first substrate 11 via the EC function unit 60 and supports the EC function unit 60 and other components. The second substrate 12 also forms the outermost layer of the first electrochromic element 1 and protects the EC function unit 60 and other components. In the following description, the space between the first substrate 11 and the second substrate 12 will also be referred to as the "inside".

[0042] The constituent material of the second substrate 12 is not particularly limited as long as it is a transparent constituent material, but a material containing a thermoplastic transparent resin is preferred. The transparent resin is the same as that used for the constituent material of the first substrate 11.

[0043] The thickness of the second substrate 12 may be the same as or different from the thickness of the first substrate 11.

[0044] The thickness of the second substrate 12 is preferably 0.1 mm or more and 10.0 mm or less, and more preferably 0.3 mm or more and 5.0 mm or less. If the thickness of the second substrate 12 is within the above range, it is possible to achieve both thinning of the first electrochromic element 1 and mechanical strength.

[0045] 1.2.3.EC Function Section Figure 4 is a partially enlarged view of the EC function unit 60 shown in Figure 3.

[0046] The EC functional unit 60 (electrochromic circuit) shown in Figure 4 comprises a first electrode 13 and a first electrochromic layer 63 sequentially stacked on the inside of the first substrate 11, a second electrode 14 and a second electrochromic layer 64 sequentially stacked on the inside of the second substrate 12, and an electrolyte layer 65 filled between the first electrochromic layer 63 and the second electrochromic layer 64.

[0047] 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, thereby injecting and removing charge into the first electrochromic layer 63 and the second electrochromic layer 64. This enables the EC function unit 60 to perform color development, holding, and decolorization.

[0048] 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, but examples 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, Al-containing ZnO, gold, silver, copper, platinum, or alloys containing these, and one or more of these can be used in combination.

[0049] The thicknesses of the first electrode 13 and the second electrode 14 are set appropriately according to the required conductivity. For example, when ITO is used as the constituent material for the first electrode 13 and the second electrode 14, the thickness is preferably 50 nm to 200 nm, and more preferably 100 nm to 150 nm.

[0050] The first electrochromic layer 63 contains a material that develops color through an oxidation reaction. The materials that develop color through oxidation reactions are not particularly limited, but examples include polymers obtained by polymerizing compositions containing radical polymerizable compounds having triarylamines, triarylamine derivatives such as triphenylamine, bisacridan compounds, Prussian blue type complexes, benzidine, nickel oxide, etc., and one or more of these can be used in combination.

[0051] Examples of Prussian blue-type complexes include materials composed of Fe(III)4[Fe(II)(CN)6]3.

[0052] Among these, polymers obtained by polymerizing a composition containing a radical polymerizable compound having a triarylamine are particularly preferred because they can operate at a constant voltage, have excellent durability for repeated color development and decolorization, and provide high-contrast electrochromic elements.

[0053] Furthermore, a composition containing a radical polymerizable compound having a triarylamine may also contain other radical polymerizable compounds different from the radical polymerizable compound having a triarylamine, and the polymer obtained by polymerizing such a composition may be composed of crosslinked products in which these radical polymerizable compounds are crosslinked.

[0054] The thickness of the first electrochromic layer 63 is not particularly limited, but is preferably about 0.1 μm to 30 μm, and more preferably about 0.4 μm to 10 μm.

[0055] The second electrochromic layer 64 contains a material that develops color through a reduction reaction. The materials that develop color through the reduction reaction are not particularly limited, but examples include inorganic electrochromic compounds, organic electrochromic compounds, conductive polymers, etc., and one or more of these can be used in combination.

[0056] 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 decolorization potential, and furthermore, being an inorganic material, it has excellent durability.

[0057] Examples of organic electrochromic compounds include low-molecular-weight organic electrochromic compounds such as azobenzene, anthraquinone, diarylethene, dihydroprene, dipyridine, styryl, styrylspiropyran, spirooxazine, spirothiopyran, thioindigo, tetrathiafulvalene, terephthalic acid, triphenylmethane, triphenylamine, naphthopyran, viologen, pyrazoline, phenazine, phenylenediamine, phenoxazine, phenothiazine, phthalocyanine, fluorane, flugide, benzopyran, and metallocene compounds. In particular, viologen compounds or dipyridine compounds are preferred. These compounds have low color potentials and exhibit good color values.

[0058] Examples of viologen compounds include those described in Japanese Patent Publication No. 3955641 and Japanese Patent Application Publication No. 2007-171781.

[0059] Examples of dipyridine compounds include those described in Japanese Patent Publication No. 2007-171781 and Japanese Patent Publication No. 2008-116718.

[0060] Examples of conductive polymers include polypyrrole, polythiophene, polyaniline, or derivatives thereof.

[0061] Furthermore, for materials that develop color through reduction reactions, it is preferable to use materials that develop color in the same tone as the materials that develop color through oxidation reactions as described above. This improves the maximum color intensity, and as a result, improves the contrast during color development.

[0062] On the other hand, when using materials that develop color through oxidation reactions and materials that develop color through reduction reactions, which have different color tones, it becomes possible to control the color development by mixing the colors.

[0063] Furthermore, either the first electrochromic layer 63 or the second electrochromic layer 64 may be set not to produce color, but the color intensity can be increased by having both produce color. This also makes it possible to reduce the drive voltage applied to the EC function unit 60, and increases the durability of the first electrochromic element 1 when repeatedly producing and decolorizing color.

[0064] The thickness of the second electrochromic layer 64 is not particularly limited, but is preferably about 0.2 μm to 5.0 μm, and more preferably about 1.0 μm to 4.0 μm.

[0065] The electrolyte layer 65 is filled between the first electrochromic layer 63 and the second electrochromic layer 64 and contains an ion-conductive electrolyte.

[0066] The electrolyte is not particularly limited, but examples include inorganic ion salts such as alkali metal salts and alkaline earth metal salts, quaternary ammonium salts, acids, and supporting salts of alkalis. Specifically, examples include LiClO4, LiBF4, LiAsF6, LiPF6, LiCF3SO3, LiCF3COO, KCl, NaClO3, NaCl, NaBF4, NaSCN, KBF4, Mg(ClO4)2, Mg(BF4)2, etc., and one or more of these can be used in combination.

[0067] Furthermore, ionic liquids can also be used as electrolyte materials. Among ionic liquids, organic ionic liquids are easy to handle because they remain liquid over a wide temperature range, including room temperature.

[0068] Examples of cationic components in the molecular structure of organic ionic liquids 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 compounds such as trimethylpropylammonium salt, trimethylhexylammonium salt, and triethylhexylammonium salt. Furthermore, as anionic components in the molecular structure of organic ionic liquids, it is preferable to use compounds containing fluorine, considering stability in the atmosphere, such as BF4. - CF3SO3 - PF4 - , (CF3SO2)2N - (SO2F)2N - These are some examples.

[0069] Such electrolyte materials may be ionic liquids obtained by arbitrarily combining cationic and anionic components.

[0070] The ionic liquid may be directly dissolved in any of the photopolymerizable monomers, oligomers, or liquid crystal materials. If the solubility in these materials is poor, a solution may be obtained by dissolving the ionic liquid in a small amount of solvent, and then this solution may be mixed with any of the photopolymerizable monomers, oligomers, or liquid crystal materials to achieve dissolution.

[0071] Examples of solvents include propylene carbonate, acetonitrile, γ-butyrolactone, ethylene carbonate, sulfolane, dioxolane, tetrahydrofuran, 2-methyltetrahydrofuran, dimethyl sulfoxide, 1,2-dimethoxyethane, 1,2-ethoxymethoxyethane, polyethylene glycol, alcohols, etc., or mixed solvents containing two or more of these.

[0072] Furthermore, in addition to low-viscosity liquids, the electrolyte can take the form of gels, solids, polymer-crosslinked types, liquid crystal dispersions, etc. Of these, the electrolyte is preferably in the form of a gel or solid. This enhances the mechanical strength and reliability of the EC functional part 60.

[0073] The thickness of the electrolyte layer 65 is not particularly limited, but is preferably about 10 μm to 100 μm, and more preferably about 20 μm to 80 μm.

[0074] Furthermore, an intermediate layer, such as an insulating porous layer or a protective layer, may be provided between the first electrode 13 and the second electrode 14, if necessary.

[0075] Furthermore, in this embodiment, the EC function unit 60 has a first electrochromic layer 63 and a second electrochromic layer 64, but either one of these may be omitted.

[0076] 1.2.4. Sealing section As shown in Figure 3, the sealing portion 55 is positioned between the first substrate 11 and the second substrate 12 and defines the colored region 70. This allows the EC functional portion 60 to be sealed within the colored region 70. The first electrode 13 and the second electrode 14 shown in Figure 3 extend beyond the sealing portion 55 to the outside of the colored region 70, thereby sealing the functional portion 60.

[0077] The constituent material of the sealing portion 55 is not particularly limited as long as it is a transparent insulating material, but examples include resin materials such as acrylic resin and epoxy resin, and inorganic oxides such as silicon oxide (SiO2), silicon oxynitride (SiON), and aluminum oxide (Al2O3).

[0078] The thickness of the sealing portion 55 is adjusted according to the thickness of the EC functional portion 60, but is preferably about 20 μm to 100 μm, and more preferably about 40 μm to 80 μm.

[0079] 1.2.5.1st auxiliary electrode As shown in Figure 3, the first auxiliary electrode 15 is laminated on the first electrode 13, which extends outside the colored region 70. The material used for the first auxiliary electrode 15 has a higher conductivity than the first electrode 13. This improves the efficiency of controlling the potential of the first electrode 13.

[0080] The constituent 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 include silver, aluminum, copper, chromium, molybdenum, etc., and one or more of these can be used in combination. The first auxiliary electrode 15 may be provided as needed, but may be omitted.

[0081] 1.2.6.Second auxiliary electrode As shown in Figure 3, the second auxiliary electrode 16 is laminated on the second electrode 14, which extends to the outside of the colored region 70. The material used for the second auxiliary electrode 16 has a higher conductivity than that of the second electrode 14. This improves the efficiency of controlling the potential of the second electrode 14.

[0082] The constituent 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 include silver, aluminum, copper, chromium, molybdenum, etc., and one or more of these can be used in combination. The second auxiliary electrode 16 may be provided as needed, but may be omitted.

[0083] 1.3. Control Unit As shown in Figure 1, the control unit 40 is located in the temple section 23 and controls the operation of the first electrochromic element 1 and the second electrochromic element 2. Since the control unit 40 performs similar control on both the first electrochromic element 1 and the second electrochromic element 2, the control for the first electrochromic element 1 will be described below as representative. Specifically, the color-developing pulse voltage VA, color-developing drive voltage VB, and decolorization pulse voltage VC described below are voltages applied only to the first electrochromic element 1, while the color-developing pulse voltage VA, color-developing drive voltage VB, and decolorization pulse voltage VC are also applied separately to the second electrochromic element 2.

[0084] Figure 5 is a functional block diagram of the control unit 40 shown in Figure 1. The control unit 40 performs color development drive, holding drive, and color decolorization drive in this order.

[0085] Color drive is a drive that changes the color intensity by applying a voltage to the first electrochromic element 1. The period during which this color drive is performed is called the "color drive period" (see Figure 6). As will be explained in detail later, during the color development drive period T1, a color development pulse voltage VA is applied to the first electrochromic element 1 during the first period TA, and a color development drive voltage VB is applied to the first electrochromic element 1 during the second period TB.

[0086] The holding drive is a drive that stops the application of voltage and opens the electrochromic circuit (circuit) of the first electrochromic element 1. In the following explanation, opening the electrochromic circuit may be referred to as "opening the element." During this holding drive, the color density is maintained by the memory effect of the first electrochromic element 1. The period during which this holding drive is performed is called the "holding drive period" (see Figure 6).

[0087] The decolorization drive is a drive that short-circuits the first electrochromic element 1. This decolorization drive eliminates the colored state and causes the element to decolorize. The period during which the element is decolorized is called the "decolorization drive period".

[0088] The control unit 40 shown in Figure 5 has a voltage measurement unit 42, a voltage determination unit 44, and a voltage application unit 46 as functional units.

[0089] The voltage measuring unit 42 measures the open-circuit voltage of the first electrochromic element 1. These open-circuit voltages are the voltages between the first electrode 13 and the second electrode 14 (open-circuit voltages) measured when the first electrochromic element 1 is open.

[0090] The voltage determination unit 44 determines the color pulse voltage VA, the color drive voltage VB, and the application time of these voltages to be applied to the first electrochromic element 1.

[0091] The function of the voltage determination unit 44 is realized by hardware, for example, a CPU, memory, and an interface. Such hardware may include, for example, a microcontroller. The CPU is a Central Processing Unit. Examples of memory include any non-volatile memory (ROM), any volatile memory (RAM), or a removable external memory element. Examples of interfaces include a digital input / output port such as USB (Universal Serial Bus). The function of the voltage determination unit 44 is realized by the CPU executing a program that has been pre-loaded into memory. Alternatively, instead of, or in conjunction with, the method in which the CPU executes a program to realize the above function may be used, in which hardware such as an FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit) realizes the above function.

[0092] The voltage application unit 46 applies the color pulse voltage VA and color drive voltage VB determined by the voltage determination unit 44 to the first electrochromic element 1 for a predetermined time.

[0093] The voltage application unit 46 includes, for example, a DC power supply, a voltage converter, and a switch. The DC power supply is a power source that generates a predetermined DC voltage and is composed of, 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 to a target value. The voltage converter may also have a function to generate a pulse width modulated voltage from the DC voltage and to change its duty cycle to bring the effective voltage closer to the target value. The switch switches the color development drive period T1, the holding drive period T2, etc., in response to user operation.

[0094] 2. Operation of the electronic dimming device Next, the operation of the sunglasses 100 to which the electronic dimming device is applied will be described. In the following description, the operation of the first electrochromic element 1 will be described as representative.

[0095] As mentioned above, in sunglasses 100, the color development drive, the holding drive, and the color decolorization drive are executed in this order, for example.

[0096] Figure 6 is a graph showing an example of the voltage applied to the first electrochromic element 1 during the color development drive period T1, and the change in voltage measured at the first electrochromic element 1 during the holding drive period T2 and the decolorization drive period T3. In Figure 6, the horizontal axis represents time, and the vertical axis represents voltage.

[0097] Figure 7 is a graph showing the change in transmittance of the first electrochromic element 1 during the color development drive period T1, the retention drive period T2, and the decolorization drive period T3 shown in Figure 6. In Figure 7, the horizontal axis represents time, and the vertical axis represents transmittance.

[0098] During the color development drive period T1 shown in Figure 6, a voltage is applied to the first electrochromic element 1. This injects charge into the first electrochromic element 1, increasing the color intensity. As a result, as shown in Figure 7, color development occurs during the color development drive period T1 in which the transmittance TR gradually decreases.

[0099] In the example shown in Figure 6, the first electrochromic element 1 is released after the color development drive period T1 ends. This initiates the transition to the holding drive period T2.

[0100] In the example shown in Figure 7, immediately after the start of the hold-drive period T2, the transmittance TR from immediately after the end of the color development drive period T1 is retained due to the memory effect. As a result, a hold-drive is performed that retains the transmittance TR without consuming power.

[0101] In the example shown in Figure 6, the first electrochromic element 1 is short-circuited after the holding drive period T2 ends. This initiates the decolorization drive period T3. During the decolorization drive period T3, the color density decreases, and decolorization is performed in which the transmittance TR increases, as shown in Figure 7.

[0102] Here, the color development drive period T1 is divided into a first period TA and a second period TB. That is, the voltage application unit 46 applies a color development pulse voltage VA to the first electrochromic element 1 during the first period TA. Next, the voltage application unit 46 applies a color development drive voltage VB to the first electrochromic element 1 during the second period TB. That is, the voltage application unit 46 applies a color development pulse voltage VA to the first electrochromic element 1 prior to applying the color development drive voltage VB. The color development pulse voltage VA is a higher voltage than the color development drive voltage VB.

[0103] In the initial stage of color development, simply applying a low voltage as in the conventional method tends to result in a relatively long delay in the decrease in transmittance (increase in color density) (see dashed line in Figure 7). By applying a relatively high color development pulse voltage VA to the first electrochromic element 1 for a short time during this initial stage, the transmittance TR can be rapidly decreased (increase in color density). As a result, the responsiveness of the transmittance change is excellent. Furthermore, because the response speed is faster when the color development pulse voltage VA is applied to the first electrochromic element 1, the color development drive period T1 can be shortened, resulting in superior convenience.

[0104] Next, in the second period T2, after the decrease in transmittance (increase in color density) has been promoted to some extent, by applying a normal color drive voltage VB, which is lower than the color pulse voltage VA, to the first electrochromic element 1, the burden on the first electrochromic element 1 can be reduced and the degradation of the first electrochromic element 1 can be suppressed, compared to a configuration in which the color pulse voltage VA is constantly applied.

[0105] Thus, according to the present invention, it is possible to increase the rate of change in color density while suppressing the degradation of the first electrochromic element 1.

[0106] The ratio VA / VB between the color pulse voltage VA and the color drive voltage VB is not particularly limited, but is preferably between 1.05 and 3.9, and more preferably between 1.12 and 2.45. This makes it possible to achieve a high level of both suppression of degradation of the first electrochromic element 1 and improvement of the rate of change in color density.

[0107] The difference between the color pulse voltage VA and the color drive voltage VB is preferably 0.1V to 2.0V, and more preferably 0.2V to 1.0V. This makes it possible to achieve a high level of both suppression of degradation of the first electrochromic element 1 and improvement of the rate of change in color density.

[0108] The color-developing pulse voltage VA is not particularly limited, but is preferably 1.1V to 3.9V, and more preferably 1.3V to 2.7V. This makes it possible to more effectively improve the responsiveness of the transmittance change and shorten the color-developing drive period T1. Furthermore, it is possible to suppress the degradation of the first electrochromic element 1.

[0109] The color-generating drive voltage VB is not particularly limited, but is preferably 1.0V to 1.9V, and more preferably 1.1V to 1.7V. This makes it possible to more reliably suppress the degradation of the first electrochromic element 1.

[0110] The color drive voltage VB can be determined by the measurement method defined in (1) or (2) below.

[0111] (1) The midpoint of the voltage values ​​at the peaks of oxidation and reduction reactions observed when cyclic voltammetry (CV) measurements are performed at a low speed (sweep speed of 2 mV / s). (2) The voltage value at which the visible transmittance decreases by 20% or more when voltage is applied for 10 seconds.

[0112] The application time of the color pulse voltage, i.e., the first period TA, is preferably 0.1 seconds or more and 15 seconds or less, and more preferably 0.2 seconds or more and 10 seconds or less. This makes it possible to more effectively improve the responsiveness of the transmittance change and shorten the color drive period T1.

[0113] Furthermore, the application time of the color-developing pulse voltage VA, i.e., the first period TA, is preferably the time for injecting an amount of charge equivalent to 1% to 50% of the amount of charge required for the first electrochromic element 1 to develop maximum color intensity, more preferably 2% to 45%, and even more preferably 3% to 40%. This makes it possible to more effectively improve responsiveness and shorten the color-developing drive period T1. In addition, it is possible to suppress the degradation of the first electrochromic element 1.

[0114] The maximum density is defined as the density at which the luminous transmittance value is lowest when the color is produced within the controllable range of the electronic dimming device.

[0115] 3. Effects of the First Embodiment The sunglasses 100 to which an electronic dimming device is applied include a first electrochromic element 1 and a second electrochromic element 2, which are electrochromic elements whose transmittance changes when a voltage is applied, and a voltage application unit 46 that performs color driving by applying a color pulse voltage VA to the first electrochromic element 1 and the second electrochromic element 2 during a first period TA, and applying a color drive voltage VB to the first electrochromic element 1 and the second electrochromic element 2 during a second period TB after the first period TA, thereby reducing the transmittance of the first electrochromic element 1 and the second electrochromic element 2. The color pulse voltage VA is a higher voltage than the color drive voltage VB, and the application time of the color pulse voltage VA (first period TA) is shorter than the application time of the color drive voltage VB (second period TB).

[0116] According to the present invention, it is possible to increase the rate of change in color density while suppressing the degradation of the first electrochromic element 1 and the second electrochromic element 2.

[0117] The number of times the color-developing pulse voltage VA is applied is not particularly limited and may be two or more times. In other words, the color-developing pulse voltage VA may be applied in multiple steps. In the case of applying the color-developing pulse voltage VA in multiple steps, the voltage for each step may be the same or different. Furthermore, the color-developing pulse voltage VA may be applied multiple times in a continuous sequence of steps, in which case the value of the color-developing pulse voltage VA may change continuously.

[0118] The application time of the color-developing pulse voltage VA (first period TA) is preferably the time for injecting an amount of charge equivalent to 1% to 50% of the total charge amount required for the development of maximum color intensity in the first electrochromic element 1 and the second electrochromic element 2. This makes it possible to more effectively improve the responsiveness of the transmittance change of the first electrochromic element 1 and the second electrochromic element 2 and shorten the time required for color development driving.

[0119] The color-developing pulse voltage VA is preferably 0.1V or higher than the color-developing drive voltage VB, and the application time of the color-developing pulse voltage VA (first period TA) is preferably 0.1 seconds or more and 15 seconds or less. This further effectively improves the responsiveness of the transmittance change of the first electrochromic element 1 and the second electrochromic element 2 and shortens the time required for color development drive.

[0120] Furthermore, the first electrochromic element 1 and the second electrochromic element 2, which are electrochromic elements, each have a first electrochromic layer 63 that develops color through an oxidation reaction, an electrolyte layer 65, and a second electrochromic layer 64 that develops color through a reduction reaction. With this configuration, an electronic dimming device can be obtained that can increase the rate of change in color density while suppressing degradation by applying a color pulse voltage VA and a color drive voltage VB.

[0121] Furthermore, the electronic dimming device in this embodiment is used as eyeglasses. With this configuration, eyeglasses with high durability for repeated switching between color and decolorization can be realized.

[0122] <Second Embodiment> 4. Operation of the electronic dimming device according to the second embodiment Figure 8 is a graph showing an example of the voltage applied to the first electrochromic element 1 during the color-development drive period T1 performed by the electronic dimming device according to the second embodiment, as well as the change in the voltage measured at the first electrochromic element 1 during the holding drive period T2 and the decolorization drive period T3. Figure 9 is a graph showing the change in transmittance of the first electrochromic element 1 during the color-development drive period T1, the holding drive period T2, and the decolorization drive period T3 shown in Figure 8.

[0123] The following explanation will focus on the differences from the first embodiment, and similar matters will be omitted from the explanation.

[0124] As shown in Figure 8, the decolorization drive period T3 is divided into a first period TC and a second period TD. Specifically, the voltage application unit 46 applies a decolorization pulse voltage VC to the first electrochromic element 1 during the first period TC. Then, during the second period TD, the voltage application unit 46 short-circuits the circuit of the first electrochromic element 1. This reduces the color density, and as shown in Figure 9, a decolorization drive is performed in which the transmittance TR increases.

[0125] The decolorization pulse voltage VC is a voltage with the opposite polarity to the coloring voltage (coloring pulse voltage VA and coloring drive voltage VB) described in the first embodiment. Furthermore, the application time of the decolorization pulse voltage VC (first period TC) is shorter than the time (second period TD) for short-circuiting the circuit of the first electrochromic element 1.

[0126] In the decolorization drive period T3, if the configuration is such that only the circuit of the first electrochromic element 1 is short-circuited, it takes a relatively long time for the transmittance to increase, as shown by the dashed line in Figure 9. In contrast, in this embodiment, prior to short-circuiting the circuit of the first electrochromic element 1, that is, prior to the second period TD, a decolorization pulse voltage VC is applied for a short time during the first period TC.

[0127] In the initial stage, period TC, where the increase in transmittance (decrease in color density) tends to take time, applying the decolorization pulse voltage VC to the first electrochromic element 1 allows for a rapid increase in transmittance TR (decrease in color density). As a result, the responsiveness of the transmittance change is excellent. Furthermore, by applying the decolorization pulse voltage VC to the first electrochromic element 1, the decolorization drive period T3 can be shortened, resulting in superior convenience.

[0128] Next, in the second period TD, after a certain degree of increase in transmittance (decrease in color density), by short-circuiting the circuit of the first electrochromic element 1, the burden on the first electrochromic element 1 can be reduced and the degradation of the first electrochromic element 1 can be suppressed, compared to a configuration in which the decolorization pulse voltage VC is constantly applied.

[0129] Thus, according to the present invention, it is possible to increase the rate of change in color density while suppressing the degradation of the first electrochromic element 1.

[0130] The decolorization pulse voltage VC is not particularly limited as long as it is a voltage with the opposite polarity to the coloring voltage (coloring pulse voltage VA and coloring drive voltage VB), but it is preferably 0.05V to 1.0V, and more preferably 0.1V to 0.9V. This makes it possible to more reliably increase the rate of change in color density.

[0131] The ratio VC / VB between the decolorization pulse voltage VC and the color development drive voltage VB described in the first embodiment is not particularly limited, but is preferably 0.02 or more and 1.0 or less, and more preferably 0.05 or more and 0.82 or less. This makes it possible to achieve a high level of both suppression of degradation of the first electrochromic element 1 and improvement of the rate of change of color development density.

[0132] The application time of the decolorization pulse voltage VC, i.e., the first period TC, is preferably the time for removing 50% to 99% of the charge amount removed during the maximum decolorization of the first electrochromic element 1, more preferably 60% to 98%, and even more preferably 70% to 97%. This makes it possible to more effectively improve responsiveness and shorten the decolorization drive period T3.

[0133] The application time of the decolorization pulse voltage VC (first period TC) 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. This makes it possible to achieve a high level of both suppression of degradation of the first electrochromic element 1 and improvement of the rate of change in color density.

[0134] The time for short-circuiting the circuit of the first electrochromic element 1 (second period TD) is preferably 40 seconds or more and 100 seconds or less, and more preferably 60 seconds or more and 80 seconds or less. This makes it possible to more effectively suppress the degradation of the first electrochromic element 1.

[0135] 5. Effects of the second embodiment The sunglasses 100 to which an electronic dimming device is applied include a first electrochromic element 1 and a second electrochromic element 2, which are electrochromic elements whose transmittance changes when a voltage is applied, and a voltage application unit 46 that performs color drive, which applies a color-developing voltage (color-developing drive voltage VB) to the first electrochromic element 1 and the second electrochromic element 2 to reduce the transmittance of the first electrochromic element 1 and the second electrochromic element 2, and decolor drive, which applies a decolorization pulse voltage VC to the first electrochromic element 1 and the second electrochromic element 2 during a first period TC, and short-circuits the circuits of the first electrochromic element 1 and the second electrochromic element 2 during a second period TD after the first period TC. The decolorization pulse voltage VC is a voltage with the opposite polarity to the color-developing voltage (color-developing drive voltage VB), and the application time of the decolorization pulse voltage VC (first period TC) is shorter than the time for short-circuiting the circuits (second period TD).

[0136] According to the present invention, it is possible to increase the rate of change in color density while suppressing the degradation of the first electrochromic element 1 and the second electrochromic element 2.

[0137] The number of times the decolorization pulse voltage VC is applied is not particularly limited and may be two or more times. In other words, the decolorization pulse voltage VC may be applied in multiple steps. In the case of a configuration in which the decolorization pulse voltage VC is applied in multiple steps, the voltage for each step may be the same or different. Furthermore, the decolorization pulse voltage VC may be applied multiple times in a continuous sequence of time, in which case the value of the decolorization pulse voltage VC may change continuously.

[0138] Furthermore, the decolorization pulse voltage VC is preferably 0.05V to 1.0V with the opposite polarity to the color development drive voltage VB, and the application time of the decolorization pulse voltage VC (first period TC) is preferably 0.1 seconds to 20 seconds. This makes it possible to achieve a high level of both suppression of degradation of the first electrochromic element 1 and improvement of the rate of change in color development density.

[0139] The application time of the decolorization pulse voltage VC, i.e., the first period TC, is preferably the time for removing an amount of charge equivalent to 50% to 99% of the amount of charge removed during the maximum decolorization of the first electrochromic element 1. This makes it possible to more effectively improve responsiveness and shorten the decolorization drive period T3.

[0140] Although the electronic dimming device of the present invention has been described above, the present invention is not limited to the embodiments described above. Furthermore, the configuration of the first embodiment and the configuration of the second embodiment may be combined. In this case, the effects of the present invention can be obtained both when color is being produced and when color is being deactivated, and an even more convenient electronic dimming device can be obtained.

[0141] For example, in the electronic dimming device of the present invention, each part of each embodiment may be replaced with any component having a similar function, or any component may be added to each embodiment. [Explanation of Symbols]

[0142] 1. First electrochromic element 2. Second electrochromic element 11. First circuit board 12 Second board 13 1st electrode 14 2nd electrode 15 1st auxiliary electrode 16 2nd auxiliary electrode 20 frames 21 Rim section 22 Bridge section 23 Temple section 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 section 60 EC function department 63 First Electrochromic Layer 64 Second Electrochromic Layer 65 Electrolyte layer 70 colored area 100 Sunglasses T1 Color development drive period T2 Holding Drive Period T3 decolorization drive period TA (Teaching Assistant) Term 1 TB Period 2 TC 1st period TD Phase 2 VA color pulse voltage VB Color drive voltage VC decolorization pulse voltage

Claims

1. An electrochromic element whose transmittance changes when a voltage is applied, A voltage application unit that performs color driving to reduce the transmittance of the electrochromic element by applying a color pulse voltage to the electrochromic element during a first period, and applying a color driving voltage to the electrochromic element during a second period after the first period, Equipped with, The aforementioned color-developing pulse voltage is a higher voltage than the aforementioned color-developing drive voltage. When the color-developing pulse voltage is denoted as VA and the color-developing drive voltage as VB, VA / VB is between 1.05 and 3.

9. The color-developing pulse voltage is 1.1V or more and 3.9V or less. The application time of the color-developing pulse voltage is shorter than the application time of the color-developing drive voltage. The voltage application unit is characterized by applying the color pulse voltage multiple times during the color drive.

2. The electronic dimming device according to claim 1, wherein the application time of the color-developing pulse voltage is the time for injecting an amount of charge equivalent to 1% to 50% of the amount of charge required for the electrochromic element to develop the maximum color intensity.

3. The color-generating pulse voltage is at least 0.1V higher than the color-generating drive voltage. The electronic dimming device according to claim 1 or 2, wherein the application time of the color-developing pulse voltage is 0.1 seconds or more and 15 seconds or less.

4. The electrochromic element is The first electrochromic layer develops color through an oxidation reaction, Electrolyte layer, A second electrochromic layer that develops color through a reduction reaction, The electronic dimming device according to claim 1, having the following features.

5. An electronic dimming device according to claim 1, used as eyeglasses.

Images