Optical densities

Photochromic lenses for eyewear serve as variable density optical filters. Other appHcations for photochromic light filters have been proposed including gla2ing appHcations for solar attenuation, variable transmission camera lenses, and shields for protection against the light flash from a nuclear explosion. 

Michael K. L., Taylor L. C., Schultz S. L., Walt D. R., Randomly ordered addressable high-density optical sensor arrays, Anal. Chem. 1998 70 1242-48. 

Smoke density. Optical density measurements on the smoke evolved from burning plastic samples were carried out using an NBS Smoke Chamber. The samples, which measured 75mm x 75mm, with a thickness of 0.6 - 4mm, were burned in the flaming mode in accordance with ASTM E662-79. Specific smoke density (Ds) values reported are the averages of three independent determinations. 

I. Ichimura, S. Hayashi, and G. S. Kino, High-density optical recording using a solid immersion lens, Applied Optics 36, 4339-4348 (1997). 

Opposite-end assembly and disassembly, MICROTUBULE TREADMILLING MICROTUBULE ASSEMBLY KINETICS OPTICAL ACTIVITY OPTICAL DENSITY Optically active substance,... 

In order to demonstrate the feasibility of the LIDA concept in high density optical recording systems, a number of dyes have been investigated and the results reported (9,10). In this paper, the results for two of these dyes, Disperse Red II, and Disperse Blue 60 are described in detail. Disperse Red II is manufactured by ICI and Disperse Blue 60 is manufactured by Dupont. Both are derivatives of 1,4-diaminoanthraquinone. Their molecular structures are shown in Figure 2. 

For a high density optical recording medium, two important parameters which characterize its capability are the size of mark and the threshold energy density required for mark creation. The size of the mark was found to be dependent on both the incident power and the exposure time. The size of the marked areas is shown in Figure 6 for different levels of power and exposure... 

The LIDA concept, discussed above, has demonstrated the potential of organic dyes for use in high density optical recording systems. However, it is apparent that the contrast density is marginal, particularly in the reflection mode. Furthermore, vacuum deposited dyes are also subject to crystallization effects which lead to focussing and archival problems. 

Fig. 9.29 Randomly ordered, addressable, high-density optical sensing array (see text for description of steps adapted from Michael et al., 1999)...

K.L. Michael, L.C. Taylor, S.L. Schultz, D.R. Walt, Randomly Ordered Addressable High-density Optical Sensor Arrays , Anal. Chem., 70(7), 1242-1248 (1998). 

M. Sisido in Photoreactive Materials for Ultra-high Density Optical Memory (Ed. M. Irie), Elsevier, Amsterdam, 1994, p. 13. 

Sieving is the simplest and most widely used technique for powder classification. This method is based only on the size of the particles and is independent of other particle properties (e.g., density, optical properties, and surface roughness). 

A ferrocene moiety-attached spironaphthoxazine derivative, 22a, which isomerizes into a thermally stable merocyanine form, 22b, and its application in rewritable high density optical data storage have been reported by Song et al. [22],... 

Selenophene-containing quinones were prepared to explore their potential use as dyes and photomaterials. They were found to have good physical and chemical properties for use as dyestuffs for laser-driven high-density optical storage media <1996H(43)941, 1996JOC4784>. 2-Aminoselenophene derivatives were synthesized as indicators for measurement of solvent polarity <2002ZNB420>. 

The cross-sectional shape of a fiber can affect many properties, e.g. luster, density, optical properties, feel of the fabric and an important characteristic called the covering power of a fabric. Covering power is the ability of fibers to occupy space. The reader can easily visualize that fibers having a circular cross-section will have a lesser covering power than fibers having a lobed cross-section. Noncircular fibers can provide a greater density in a fabric than circular fibers. 

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