Films polarizing

Polymer Ferroelectrics. In 1969, it was found that strong piezoelectric effects could be induced in the polymer poly(vinyhdene fluoride) (known as PVD2 or PVDF) by apphcation of an electric field (103). Pyroelectricity, with pyroelectric figures of merit comparable to crystalline pyroelectric detectors (104,105) of PVF2 films polarized this way, was discovered two year later (106.)... 

Most of the LC polymer systems discussed so far contain the LC moiety incorporated in the polymer main chain. One of the few examples of polarized emission of light using a side-chain LC system was reported by Chang et al. [107]. A polyacrylate was used as the polymer backbone. The nematic LC side-chains consisted of ethyl- and propyl-substituted bis-tolan units. When deposited on a rubbed PEDOT film, polarized EL dichroic ratios were reported to be around 6. 

Title Norbornene-Based Polymer, Film, Polarizing Plate and Liquid-Crystal Display Device... 

Additional norbornene polymers, (I), were previously prepared by Watanabe et al. (1) and used in films, polarizing plates, and liquid-crystal devices. 

Iodine makes blue colored complexes with many substances such as starch [1, 2] nylon-6 [3], poly(vinyl pyrrolidone) [4], poly(vinyl alcohol) PVA [5, 6], From the application point of view, the blue PVA-Iodine complex is the most important among them, for it is widely used for film polarizers [7,8]. The polarizers are prepared by soaking PVA films in a solution of iodine and potassium iodide (KI) with boric acid, and subsequent drawing to cause the high... 

In the contribution written by Miyasaka the complex of system poly(vinyl alcohol) and iodine is discussed. Such systems are important materials as film polarizers. It is shown that different structures can be formed depending on the concentration of iodine and the degree of orientation of the polymer. The optical behaviour is explained by the structure of the material. 

Poly[(p-butoxyphenyl)phenylsilane] (PBPPS) has been employed as an emissive layer of an organic EL device.95 PBPPS was spin coated onto an uniaxially oriented poly(diethylsilane) (PDES) ultrathin film. Polarized NUV-EL was observed and the polarization direction was found to be identical with the drawing direction of the friction-transfer process for the PDES film, indicating that PBPPS in the emissive layer was aligned parallel to the uniaxial orientation of PDES. 

Figure 1.9. The optical parametric amplifier (OPA). BS, beam splitter TFP, thin-film polarizer HWP, half-wave plate IMP, dichroic beam splitter or long wave pass filter F,...

Ih of passivation [17]. In this study, it was observed that after 1 h of passivation the amount of disorder increased sharply for a Cr content of the alloy between 14.7 and 16.5%. The effect of aging was tested only in ex-situ conditions and it was observed that it favors the (re)crystallization of the passive film for 18 and 21% Cr content [15]. The structural order observed in the passive film was consistent with the (0001) orientation of a-Cr203. In the case of pure Fe sputter-deposited thin films polarized at high anodic potentials in borate buffer solution, the same group reported long-range crystalline order in both ex-situ and in-situ conditions of examination [18]. 

Some drawbacks remain with the commercial packages, however. Packages for anisotropic measurements are not currently available, and most of the polarization accessories available from the major companies are film polarizers that are not useful. Furthermore, only a few of the commercial systems (such as the one made by Jobin Yvon, Inc.) work in the NIR. Most basic systems are designed for silicon detectors that go from about 200-1150 nm (G.R. Rossman, pers. comm. 2000). For this reason, astute users are well served to build their own equipment. 

Figure 14.22 Decomposition of the OMA polaron band during the PANI/Sn02 film polarization at 450 mV in a pH 3 solution in two sub-bands at 3.16 eV (bipolaron) and 2.88 eV (isolated polaron/polaron lattice).

Figure 14.25 In situ Raman spectra of a PANI/Sn02 film polarized in pH 3 solution (a) pristine material (b) after 4300 cycles—> 450 mV (c) after 3000 cycles—> 550 mV Bleaching at —300 mV.

Fig. 7.11 Photomicrographs of the different forms of indomethacin (crystal film, polarized light) and IR spectra recorded with an FT-IR microscope of corresponding crystal films prepared between ZnSe discs.

Fig. 9.33 Schematic layout of the regenerative amplifier based on an active-mirror cryogenie cooled Yb YAG ceramic. TFPfj) and TFP(2) thin film polarizers, FR Faraday rotator, DM dichroie flat mirror (AR 750-1000 nm, HR 990-1170 nm), and Pockels cell Lasermetrics 5046E. Reproduced with permission from [261]. Copyright 2009, Elsevier...

The temperature dependence of the film polarization calculated by the above free energy minimization is reported on Fig. 3.11 for different PmIPs ratios. It is seen, that surface polarization P (related to built-in field) plays a dual role. First, it induces a non-zero polarization in the films with thickness less then critical one. Second, for films with thickness more then critical one, it transfers the polarization to the temperatures higher than transition one, see Fig. 3.11a, b respectively. It follows from Fig. 3.11b, that at P Q,Eq = 0 the polarization behavior is similar to that for bulk polarization in external electric field. Without built-in field, the polarization equals zero at 7 = Td, see dashed line in Fig. 3.1 lb. 

Iwakawa, Y. Kawaguchi, Y Inoue, T. Hydrophihc polymer films, polarizer films, optical films, and image display devices. Jpn. Kokai Tokkyo Kobo JP 2006023328, 2006 Ghent. Abstr. 2006, 144, 160410. 

Using Polarizer Using Conventional with WV film Polarizer... 

Compensation film Polarizer Collimation film Diffuser Light guide... 

Y. Bobrov, C. Cobb, P. Lazarev, et al.. Lyotropic thin film polarizers, SID Tech. Digest, 31, 1102 (2000). 

Figure 4 Relationship between piezoelectricity and orientation of dipoles for films polarized at various and films heat-treated at various temperatures.

The relationship between the piezoelectricity d and the orientation of dipoles 0 (b) are given in Figure 4, for the films polarized at a high temperature with various E, and for the films heat-treated at various temperatures. iSe polarization at 140°C seems to induce the piezoelectricity with less orientation at low E, the piezoelectricity becomes parallel to the orientation of dipoles with medium E, and only the orientation of dipoles continues to increasi as E increases further. When the films polarized at 140 with 670kv/cm were heat-treated at various temperatures, the orientation of dipoles decreases more quickly than the piezoele-... 

A negative electric field was applied to the piezoelectric films(polarized at 140 C and 670kv/cm)at room temperature under fixed conditions, and subsequently decreased the d-constant of the films, giving the negative d-constant at last. 

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