Showing papers on "Electrochromism published in 1975"
TL;DR: In this paper, the authors developed a theory that gives the correct time dependence and magnitude of the current for double extraction in amorphous WO3 films containing electrons and mobile cations.
Abstract: Measurements have been made of the current flow in amorphous WO3 films containing electrons and mobile cations. In a configuration in which electrons are extracted at one contact and cations at the other, the current decays as t−3/4 over many decades of time. By using space‐charge current flow ideas, we develop a theory that gives the correct time dependence and magnitude of the current for this double‐extraction phenomenon.
181 citations
TL;DR: In this article, it was shown that the positive ion remains fully ionized even in the presence of high densities of injected electrons in amorphous WO3 films and in tungsten bronzes.
Abstract: X‐ray photoelectron spectra of colored WO3 films, thermodynamic analysis of galvanic behavior of the tungstic oxide cathode, plus other new lines of evidence, clearly establish the previously uncertain mechanism of the electro‐optic effect in amorphous WO3, viz., a simultaneous injection of electrons and positive ions into a film via an electrochemical process, with the consequent development of a low‐x tungsten bronze. The positive ion, in both the films and in tungsten bronzes, remains fully ionized even in the presence of high densities of injected electrons.
114 citations
TL;DR: In this article, a model is proposed in which the electrocoloration process is attributed to the formation of a ‘tungsten-blue’ phase following cathodic reduction by active hydrogen.
Abstract: Studies of electrochromism in evaporated and chemically prepared tungsten-oxide films have shown that electrocoloration takes place only in films containing H2O. A model is proposed in which the electrocoloration process is attributed to the formation of a ‘tungsten-blue’ phase following cathodic reduction by active hydrogen.
100 citations
Patent•
21 Aug 1975TL;DR: An electrochromic data display and imaging device which may be formed by sandwich arrangement of the imaging area and the counter-electrode area, with a suitable ion-conductive layer between, having means to illuminate the image area.
Abstract: An electrochromic data display and imaging device which may be formed by sandwich arrangement of the imaging area and the counter-electrode area, with a suitable ion-conductive layer between, having means to illuminate the imaging area
37 citations
IBM1
TL;DR: In this paper, several different types of electrochromic display devices are compared and compared in terms of their applicability to information display and it is concluded that electrochromism is best suited for direct-addressed displays.
Abstract: Several different types of electrochromic display devices are discussed. Their electrooptical properties and device characteristics are investigated and compared. Performance parameters for these devices are discussed in terms of their applicability to information display. It is concluded that electrochromism is best suited for direct-addressed displays.
31 citations
Patent•
06 May 1975TL;DR: In this article, a controllable electrochromic indicator device is described, which includes two electrodes, an electro-chromic layer and an adjacent charge-carrier-transmitting insulator layer.
Abstract: A controllable electrochromic indicator device is disclosed which includes two electrodes, an electrochromic layer and an adjacent charge-carrier-transmitting insulator layer situated between the two electrodes and at least one of the electrodes being deposited on a supporting plate and at least one of the electrodes being transparent The charge carrier transmitting insulator layer is a good ion conductor and functions to almost completely block the flow of electrons At least one of the electrodes is non-polarizable and is disposed in direct contact with the ion conductor
25 citations
Patent•
14 Mar 1975TL;DR: An electrochromic medium and an auxiliary redox system comprising reversibly oxidizable metallic ions, for example iron, a complexing agent for the metallic ion, particularly a carboxylic acid such as tartaric acid, and an inert solvent as discussed by the authors.
Abstract: An electrochromic medium and electrochromic devices containing such mediums comprising an electrochromically active material, an auxiliary redox system comprising reversibly oxidizable metallic ions, for example iron, a complexing agent for the metallic ions, particularly a carboxylic acid such as tartaric acid, and an inert solvent.
25 citations
24 citations
Patent•
19 Aug 1975
TL;DR: In this article, a display device suitable for timepieces and the like includes a solid electrochromic material and a solid electrolyte, which is free of liquid components and is substantially thinner than conventional display devices.
Abstract: A display device suitable for timepieces and the like includes a solid electrochromic material and a solid electrolyte. The device is free of liquid components and is substantially thinner than conventional display devices. The problem of leakage arising from the use of liquid electrochromic material or liquid electrolyte is avoided.
16 citations
Patent•
15 Jul 1975
TL;DR: An electrochromic display cell has a first transparent plate for viewing said display therethrough and a second plate having thereon a reflective metal coating, said coating being inert to electrochemical oxidation under the conditions of operation of said display as mentioned in this paper.
Abstract: An electrochromic display cell has a first transparent plate for viewing said display therethrough and a second plate having thereon a reflective metal coating, said coating being inert to electrochemical oxidation under the conditions of operation of said display Conductive leads are covered, at least in part, by an insulating film
15 citations
Patent•
04 Apr 1975TL;DR: In this paper, a counter electrode structure of a transition metal electrochromic compound for use in an electro-optical device, which is useful in control of visible and infrared absorption by windows, in data display devices and the like, typically comprising in sandwich arrangement a pair of electrodes, and disposed therebetween, a layer of transition metal electrolychromic compounds and a semi-solid highly conductive sulfuric acid gel electrolyte, one of the electrodes being said counter electrode.
Abstract: A counter electrode structure of a transition metal electrochromic compound for use in an electro-optical device, which is useful in control of visible and infrared absorption by windows, in data display devices and the like, typically comprising in sandwich arrangement a pair of electrodes, and disposed therebetween, a layer of transition metal electrochromic compounds and a semi-solid highly conductive sulfuric acid gel electrolyte, one of the electrodes being said counter electrode. The gel exhibits good conductivity, stability and compatibility with the electrochromic layers. The present counter electrode is more efficient and has a longer lifetime.
Patent•
13 Jan 1975
TL;DR: An electrochromic display device has transparent electrodes on a substrate and coated with electro-chromic material for selectively displaying optical patterns, a counter-electrode on a parallel substrate also coated with the same material, and a thin porous separator membrane for closely spacing the substrates as mentioned in this paper.
Abstract: An electrochromic display device having transparent electrodes on a substrate and coated with electrochromic material for selectively displaying optical patterns, a counter-electrode on a parallel substrate also coated with electrochromic material, a thin porous separator membrane for closely spacing the substrates, the separator pores saturated with liquid electrolyte contacting the electrochromic layers and pigment providing a contrasting background for the first mentioned electrochromic layer and hiding the second electrochromic layer.
TL;DR: In this article, the mechanisms and capabilities of photochromism and electrochromism in Ni,Mo doped SrTiO 3 ; and hologram storage in Fe doped LiNbO 3.
Patent•
12 Mar 1975
TL;DR: In this article, a liquid crystal, electrochromic or other electro-optical material is sandwiched between two glass substrates, and an electric field is applied to the electro optical material to display time and other information on a watch.
Abstract: A liquid crystal, electrochromic or other electro-optical material is sandwiched between two glass substrates. An electric field is applied to the electro-optical material to display time and other information on a watch. The lower glass substrate is thinner than the upper substrate so as to create clear displays and to enable the manufacture of a thin watch which is also light weight and shock resistant.
Patent•
19 Sep 1975
TL;DR: An electrochromic display for selectively displaying optical patterns comprising a sandwich type structure which includes transparent front electrodes, electro-chromic layers on the front electrodes and an electrolyte and a special electroreactive layer on a rear electrode is described in this article.
Abstract: An electrochromic display for selectively displaying optical patterns comprising a sandwich type structure which includes transparent front electrodes, electrochromic layers on the front electrodes, an electrolyte and a special electroreactive layer on a rear electrode. The electroreactive layer, which serves as hydrogen source, is composed of electrochemical material which is first oxidized and subsequently heat treated in a hydrogen or forming gas atmosphere to improve the operating and life characteristics of the display. The electrodes are mounted or deposited respectively on parallel substrates which form the outer structures of a hermetically sealed display arrangement. The electroreactive layer can be a single layer structure serving the functions of both the rear electrode and hydrogen source material.
Patent•
02 Sep 1975
TL;DR: An electrochromic display device has transparent front electrodes on a substrate, front electrodes being coated with Electrochromic material having different oxidation states for displaying optical patterns, a back electrode on a parallel substrate also coated with electro-chromic materials, a thin porous separator between the substrates, a liquid electrolyte contacting the Electro-Chromic layers, said electrolyte being saturated with ElectroChrome materials in each of the oxidation states to reduce the degradation of the electro-Chrome layers as they pass through each of their oxidation states.
Abstract: An electrochromic display device having transparent front electrodes on a substrate, said front electrodes being coated with electrochromic material having different oxidation states for displaying optical patterns, a back electrode on a parallel substrate also coated with electrochromic material, a thin porous separator between the substrates, a liquid electrolyte contacting the electrochromic layers, said electrolyte being saturated with electrochromic materials in each of the oxidation states to reduce the degradation of the electrochromic layers as they pass through each of the oxidation states. The saturating materials are tungsten trioxide, hydrogen tungsten oxide, and tungsten dioxide in the electrochromic display described.
Patent•
06 Oct 1975TL;DR: A totally solid electrochromic display cell comprising a display electrode of tungsten oxide or vanadium oxide, a counter electrode of metallic silver or a silver-containing compound, and a solid electrolyte of a mixed inorganic silver salt including silver iodide in contact with both electrodes is described in this paper.
Abstract: A totally solid electrochromic display cell comprising a display electrode of tungsten oxide or vanadium oxide, a counter electrode of metallic silver or a silver-containing compound, and a solid electrolyte of a mixed inorganic silver salt including silver iodide in contact with both electrodes.
Patent•
03 Jan 1975
TL;DR: An electronic timepiece with a digital display device employing electrochromic materials, such as titanate and niobate, as an electro-optical element, was proposed in this paper.
Abstract: An electronic timepiece with a digital display device employing electrochromic materials, such as titanate and niobate, as an electro-optical element. An electrochromic material produces different states of coloration depending upon the polarity of voltage applied thereto for a remarkably long period, and with a minimum of power consumption, whereby the timepiece enjoys a minimization in its size, a long life for its battery, and a variable design in the display.
TL;DR: None of these technologies is suitable for video applications; however, it is quite likely they will be used in digital displays where low power consumption is important and where only a small numbtr of display elements are required.
Abstract: Liquid Crystal, Electrochromic, and Electrophoretic displays are the three examples of low power, passive displays which are described in this review. Their principles of operation are briefly summarized and their properties are compared in six different categories. None of these technologies is suitable for video applications; however, it is quite likely they will be used in digital displays where low power consumption is important and where only a small numbtr of display elements are required.
Patent•
11 Jul 1975
TL;DR: In this article, the coloration of the layer of electrochromic material exhibits an improved match to the spectral sensitivity of the human eye, and less electrical energy is required to operate the device at satisfactory viewing levels as compared to conventional devices where the color center absorption peak is less closely matched to the spectrum of human eye.
Abstract: An electrochromic device includes a layer of electrochromic material, such as tungsten oxide. The electrochromic material includes a dopant, such as molybdenum oxide. A sufficient amount of the dopant, for example, 2% by atomic weight, functions to shift the natural color center absorption peak of the electrochromic layer. Due to the shift of the color center absorption peak, coloration of the layer of electrochromic material exhibits an improved match to the spectral sensitivity of the human eye. Consequently, less electrical energy is required to operate the device at satisfactory viewing levels as compared to conventional devices where the color center absorption peak is less closely matched to the spectral sensitivity of the human eye.
TL;DR: A review of the fundamental concepts associated with passive displays based on liquid crystals and other liquid media is presented in this article, where the operation of dynamic scattering and field effect type liquid crystal displays is discussed in detail.
Abstract: A review of the fundamental concepts associated with passive displays based on liquid crystals and other liquid media is presented. The operation of dynamic scattering and field-effect type liquid crystal displays is discussed in detail. Electrophoretic, electrochromic, rotatable dipole, and liquid vapour displays are also described.
Patent•
25 Jun 1975
TL;DR: A display device includes a layer of photoconductive material and an electrochromic material between electrodes as mentioned in this paper, which is useful as an image converter for the spectrum from X-rays to infra-red and as a memory device.
Abstract: A display device includes a layer of photoconductive material and a layer of electrochromic material between electrodes The device is useful as an image converter for the spectrum from X-rays to infra-red and as a memory device
Patent•
30 Dec 1975TL;DR: A controllable electrochromic indicator device with a transparent first and a second electrode, the second electrode having a porous solid impregnated with a liquid electrolyte is described in this paper.
Abstract: Electrode for a controllable electrochromic indicator device with an electrochromic layer between a transparent first and a second electrode, the second electrode having a porous solid impregnated with a liquid electrolyte.
01 Jan 1975
TL;DR: In this article, the development of a solid state electro-chromic device for display applications is reported, which consists of a multilayer thin film system and therefore, successful fabrication of it requires optimization of each constituent layer with respect to various deposition parameters.
Abstract: The development of a solid state electro-chromic device for display applications is reported in this paper. The electro-chromic structure consists of a multilayer thin film system and therefore, successful fabrication of it requires optimization of each constituent layer with respect to various deposition parameters. We discuss the physical principle, the fabrication methods and operational characteristics of a typical system. Some of the other systems involving "super-ionic conductors" and impurity doped systems are also considered.
01 Jan 1975
TL;DR: In this article, LiquidCrystal, Electrochromic, and Electro-Electrophoretic displays are compared in terms of low power, passive displays for video applications, and their principles of operation are summarized and their properties are compared.
Abstract: LiquidCrystal, Electrochromic, andElectrophoretic displays arethethreeexamples of lowpower, passive displays whicharedescribed inthisreview. Theirprinciples ofoperation are briefly summarized andtheir properties arecomparedinsixdifferent categories. Noneofthese technologies issuitable forvideoapplications; however, itisquite likely theywill beusedin digital displays wherelowpowerconsumption isimportant andwhereonlyasmall numbtrof display elements arerequired.
01 Jan 1975
TL;DR: In this article, the authors studied electrical and (uv) photo-coloration of MoO 3 and found that both electrical and photo coloration are accompanied by a chemical phase change, based on this, together with electrical charging/discharging characteristics, they concluded that both photo-and electro-chromism in such materials is chemical in nature.
Abstract: Electrochromic devices for use as alphanumeric displays have been the subject of recent interest. Their optical absorption is changed when current passes through them or if exposed to uv light. Electrochromic materials are generally transition metal compounds such as WO 3 and MoO 3 . Some people have suggested coloration occurs by electrochemical redox. Others have proposed that coloration results from electron filling of deep traps incorporated during film deposition. We studied electrical and (uv) photo-coloration of MoO 3 and found that both electrical and photo-coloration are accompanied by a chemical phase change. Based on this, together with electrical charging/discharging characteristics, the conclusion is reached that both photo-and electro-chromism in such materials is chemical in nature. The significance of this, regarding electrochromic devices is discussed.