Mirrors, switchable

The main application areas for electrochromic systems are in electrically switchable rear-view car mirrors for anti-dazzle, in glazing units for temperature and light control and in visnal displays. The main advantage offered by electrochromic systems in the first two of these applications is the fact that the cells can be made very large, i.e. one cell can comprise a whole glazing unit. 

Electrically switchable rear-view mirrors for cars and trucks have been in commercial production since the early 1990s, the leading company being the Gentex Corporation. The Gentex mirror consists of an ITO-glass surface, with the conductive side inwards, and a reflective metallic surface, spaced less than a millimetre apart. In the gap between these two electrodes is the solution electrolyte that is coloured at the anode by formation of the stable radical cation, similar to Wurster s... 

At present metal hydrides, owing to their unique properties, find applications (Figure 2) in many fields of science and technology, associated with hydrogen storage, thermal compression, separation, electrochemistry, switchable mirror, etc. 

Optical Properties of Metal Hydrides Switchable Mirrors I 275... 

The purpose of this article is to review the essential properties of switchable mirror materials with special emphasis on their optical properties. So far three generations of hydrogen-based switchable mirrors have been discovered ... 

Each of these generations has specific properties that are described separately in the next sections. The rare-earth switchable mirrors are historically important... 

The growth and microstmcture of switchable mirror thin fllrns involves specific aspects that need to be discussed before describing their physical properties. We focus first on Y, La and rare-earth films (for convenience all abbreviated as RE films), deposited in both their metallic and hydride forms. Some references to second-generation mirrors (Mg-RE) are included and third-generation switchable mirrors (Mg-TM) are shortly discussed separately. 

First-Generation Switchable Mirrors Rare-Earth Metal Hydride Films... 

One of the most important aspects of the discovery of switchable mirrors is the fact that in the form of thin films rare-earth hydrides (REH ) are amenable to a whole series of experiments, which were often impossible with bulk samples since hydrogen absorption resulted in a total disintegration of bulk samples. 

Hysteretic effects are considered in Section 7.2.3.3. Although papers have appeared on, for example Pr [107], Sm [108], Gd [109,110] and Dy hydrides [111] most investigations on switchable RE hydrides are dealing with Y. In this way Y has become the archetypal material for the first generation switchable mirrors. Scandium, although trivalent, does not form a trihydride under normal conditions (room temperature and 10 Pa) [112]. 

Theoretical Models for the First-Generation Switchable Mirrors... 

Second-Generation Switchable Mirrors Magnesium-Rare Earth Films... 

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