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Ellipsometric studies are generally carried out in the reflection mode rather than in the transmission mode, requiring invariably opaque substrates or substrates in which the backreflection is minimized or suppressed by different methods. In the present research we used a transmission and reflection photoellipsometry method to study electrochromic materials and their multilayer systems deposited on thick substrates. The role of the substrate is examined carefully, and the contributions from multiple reflections in the substrate are taken into account in the theoretical treatment. This procedure not only allows the study of thin films deposited on quasi-transparent substrates, but when carried out in conjunction with reflection measurements it greatly improves the accuracy in the determination of the optical constants. Optical measurements are carried out on an automatic reflection transmission spectroscopic ellipsometer. Solid-state ionic materials used in electrochromic systems such as indium tin oxide, tungsten oxide, and their multilayer structures deposited on glass substrates are used as examples. A software based on the above theory, OPTIKAN, was developed to model and analyze such systems. It is demonstrated that the photoellipsometry method proposed is especially suited to analyzing electrochromic materials and transmitting devices in a nondestructive way.

We propose a method that uses reflection and transmission photoellipsometry to analyze samples consisting of thin films combined with semitransparent thick layers or substrates in the form of multilayer structures. A thick film or substrate is defined as a layer for which no interference effects can be observed for a given wavelength resolution, and contributions from multiple reflections in the substrate are taken into account in the theoretical treatment. An automatic reflection-transmission spectroscopic ellipsometer was built to test the theory, and satisfactory results have been obtained. Examples corresponding to a strongly absorbing film deposited on a glass substrate and a highly transmitting film also deposited on glass are shown. In both cases a good fit between theory and experiment is found. The photoellipsometric method presented is particularly suited to the analysis of actual samples of energy-efficient coatings for windows. Key words: Reflection-transmission ellipsometry, transparent substrates.

Analysis of the effect of lithium doping on the electrical and optical properties of LiNbO3 and LiBO2 thin films reveals that lithium doping enhances the ionic conductivity of the films to high levels with a maximum conductivity of 4.5 times 10 to the power of -6 S per cm. The films display high level transmission in the 350 to 2500 nm spectral region. The simultaneous increase in transmission and conductivity enables the use of lithium doping for designing ion conductors for transmissive solid-state electrochromic systems.

The optical characteristics of a gelatin film with a very low concentration of silver particles was investigated. The results showed that the gelatin film featured isotropic properties and well-separated and noninteracting silver particles. An apparent blue shift in the plasma resonance absorption was observed with the loss function when the silver particles varied in size from 22 to 10 nm.

With the aim of improving the photonic efficiency of an organic light emitting diode (OLED) and its display duration, both the hole transport layer (HTL) and the emitting layer (EL) were prepared as nanostructured thin films. For the HTL, nanocomposite films were prepared by spin-coating a homogeneous solution of low molecular weight poly(4-styrenesulfonate) (PEDOT-PSS) and surfactant-capped TiO2 nanocrystals onto low resistivity indium tin oxide (ITO) substrates; for the EL, nancrystalline titatium oxide (nc-TiO2)-embedded Poly[2-methoxy-5-(2′-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV+nc-TiO2) conjugate polymers were spin-coated onto the HTL. Also, for a shallow contact of Al/LiF/MEH-PPV instead of Al/MEH-PPV a super LiF thin film was deposited onto the EL by vacuum evaporation. The resulting multilayer OLED had the following structure of Al/LiF/MEH-PPV+nc-TiO2/PEDOT-PSS+nc-TiO2/ITO. Characterization of the nanocomposite films showed that both the current-voltage (I-V) characteristics and the photoluminescent properties of the nanocomposite materials were significantly enhanced in comparison with the standard polymers. OLEDs made from these layers would exhibit a large photonic efficiency. [ABSTRACT FROM AUTHOR]

Thermally evaporated lithium borate films (LiBO2) are investigated to determine their optical and electrical properties. The investigation is used for the application of these films as conductors of lithium ions in electrochromic devices. A high degree of transmission in the solar spectral range is exhibited by LiBO2 films and lithium ion conductivity is about 10 to the power of -7 times S per centimeter. Such films possess high potential for use in electrochromic devices as ion conductors.

Presents information on a study which explained the attenuation of the parallel-band absorption in aluminum particles by using an approach based on a theory developed by Wood and Ashcroft, in terms of a quantum mechanical size effect. Theoretical considerations; Experimental results; Calculation of the transmittance using the Maxwell-Garnett theory.

Presents a study that investigated the p-polarized optical properties of aggregated gold films. Background on effective depolarization factors; Application of different types of distribution functions for the axial ratio; Analysis of the calculated p-polarized light transmittances.

Studies the electrochromic behavior of all-solid-state device. Details on the experiment; Results of the study; Conclusion.

Presents a study which examined the optical and electrochemical properties of vanadium pentoxide gel thin films. Polycondensation of vanadium components; Experimental procedures; Results.

Presents a study which gave evidence of resonant optical absorption with tungsten oxide (WO[sub3]) overcoat on thick silver films. Differential reflectance measurements for WO[sub3] overcoats; Reasons that WO[sub3] has been chosen as the discontinuous overlayer; Comparison between WO[sub3] and MgF[sub2].