Optical transmission characteristics

Films of pure CNLCs have a unique transmission behavior as CP light with the same sense of circular polarization as the CNLC is filtered out by reflection, while CP light of the opposite handedness as the CNLC film is transmitted. This selective optical transmission characteristic is referred to as a one-dimensional photonic stop-band or a selective reflection band. The stop-band is centered at a certain wavelength Ac, which is dependent on the pitch length p and the average refractive index n of the CNLC ... 

Figure 46. The optical transmission characteristics of a UV-3 filter for the Perkin Elmer Micralign 500. The filter was designed for Mid-UV projec-tion lithography. Note that it is essentially opaque in the near and deep UV. The wave length of the major mercury emission lines are noted.

The optical transmission characteristics of three PLZT comp-... 

Figure 7. Optical transmission characteristics of three selected PLZT compositions...

A spectrum analyzer (Spectro 320, Instrument Systems, Germany) was used to study the optical transmission characteristics (in the visible spectrum) of the dyes and of the dye-sensitized photoelectrodes. The I-V characteristics, and hence efficiency, were obtained using a locally made manual I-V measuring apparatus with a 500 Q linear potentiometer as the variable load. Simulated light (Phillips Electric, Japan) of 1,000 W/m incident radiation was used. The overall conversion efficiency was determined from the relationship... 

The optical transmission characteristics of the following four FPEOF/PMMA pseudo-SlPNs have also been studied FPE012F/PMMA (Cso content = 1.1%), FPE012F/PMMA (Cso content = 1.5%), FPEO20F/PMMA (Cso content = 2.7%) and FPE05F/PMMA (Cgo content = 4.5%). Figure 4.9 shows the transmission spectra of solid films of the four pseudo-SIPNs. Similarly, the spectrum also red-... 

Plastics are suitable for most optical applications that utilize transparent materials, including color carriers. Color filters have all types of standard transmission characteristics that can be made and, because of the uniqueness of the plastic structure, a large number of dichroic and trichroic materials are possible that have different colors when viewed from different angles. One application for this is in polarizing filters. 

Figure 2.28 Transmission characteristics of various optical materials (A) glass, (B) plastic, (C) silica glass, (D) quartz.

Figure 12.8. Transmission characteristics of some commonly used optical fibers, (a) glass fiber (b) gradient-index fiber (c) plastic-clad silica fiber (d) plastic fiber. (Reproduced with permission from the Ealing Corporation.)...

The most important characteristics of this two-layer system is the so-called "edge sharpening" effect. During exposure, as Ag is doped into the Ge-Se layer, two other phenomena happen. The optical transmission of the Ag2Se film increases as Ag is depleted. This enhances the exposure in the exposed areas just as the case of photobleaching of conventional organic... 

Table 6.29 Comparison of Transmission Characteristics for Copper Wire and Optical Fiber...

Amorphous polymers characteristically possess excellent optical properties. Unlike all the other commercially available fluoropolymers, which are semicrystalline, Teflon AF is quite clear and has optical transmission greater than 90% throughout most of the UV, visible, and near-IR spectrum. A spectrum of a 2.77-mm-thick slab of AF-1600 is shown in Figure 2.5. Note the absence of any absorption peak. Thin films of Teflon AF have UV transmission greater Ilian 95% at 200 mm and are unaffected by radiation from UV lasers. The refractive indexes of Teflon AF copolymers are shown in Figure 2.6 and decrease with increasing FDD content. These are the lowest refractive indexes of any polymer family. It should be noted that the abscissa could also be labeled as glass transition temperature, Tg, since Tg is a function of the FDD content of the AF copolymer. Abbe numbers are low 92 and 113 for AF-1600 and AF-2400. 

The following table lists the more common materials used for optical components (windows, prisms, etc.) in the infrared region of the electromagnetic spectrum. The properties listed are needed to choose the materials with optimal transmission characteristics.1 2 The thermal properties are useful when designing experiments for operation at elevated temperatures.3-5 This listing is far from exhaustive, but these are the most common materials used in instrumentation laboratories. 

Optical transmission is an essential physical characteristic of halide glasses in the sense that, except for beryllium-based fluoride glass, this property differentiates... 

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