Narrow-band emitters

Figure 135 Molecular structures of lanthanide complexes of europium (Eu), tris (thenoyltrifluoroacetonato) Eu3+ (a), tris(thenoyltri-fluoroacetonatoXmonophenanthroline) Eu3+ (b), and terbium (Tb), tris(acetylacetonato) Tb3+ (c) employed as narrow-band emitters in organic EL devices (see Ref. 19, 425, 534-536 and 539).

Resolution, however, is affected by lens astigmation, coma, spherical aberration, and chromatic aberration. The first three factors are dependent on the excellence of the lens, but chromatic aberration can be minimized by using line emitters (monochromatic) or narrow-band emitters for each of the three image sources. Because a specific lens design possesses different magnification for each of the three primary colors (the index of refraction varies with wavelength), throw distance for each must also be adjusted independently to attain perfect registration. 

Fig. 2. General configurational—coordinate diagrams for (a) broad-band absorbers and emitters, and (b) narrow-band or line emitters. The ordinate represents the total energy of the activator center and the abscissa is a generalized coordinate representing the configuration of ions surrounding the...

El-Kady, Biswas R., Ye Y., Su M.F., Puscasu I., Pralle M., Johnson E.A., Daly J. and Greenwald A, Tunable narrow-band infrared emitters from hexagonal lattices, Photonics and Nanostructures 2003 1 69-77. 

Transition metal ion activators that emit in the visible region of the spectrum belong mainly to the d-3 and d-5 electron configurations, d ions have a characteristic narrow band emission that is largely independent of the crystalline host, d ions are broad band emitters with emission wavelengths that are very sensitive to details of the crystal structure. 

After that, Cao and coworkers synthesized a series of copolymers derived from DOF and narrow-band-gap 4,7-di-2-thienyl-2,l,3-benzothiadiazole (DBT) with various feed ratios of DOF/DBT [58]. The highest quantum efficiency and brightness were only 1.4% and 259 cdm2, respectively, from the device based on the copolymer with 15% DBT content (ITO/PEDOT PSS/27/Ba/Al). As DBT content increases from 1 to 35%, the EL emission peak shifts from 628 nm to 674 nm, indicating that the copolymers are promising candidates as pure-red emitters though the performance needs to be further improved. 

Xie R, Chen K, Chen X, Peng X (2008) InAs/InP/ZnSe core/shell/shell quantum dots as near-infrared emitters bright, narrow-band, non-cadmium containing, and biocompatible. 

The mechanism of radiative transfer in flares was found to depend on compn, flare diameter and pressure (Ref 69). The flare efficiency calcn is complicated by the drop-off in intensity at increasing altitudes and at very large diameters owing to the lower reaction temps (Ref 11, p 13) and the narrowing of the spectral emittance band (Ref 35). The prediction of the light output in terms of compn and pressure (ie, altitude) is now possible using a computer program which computes the equilibrium thermodynamic properties and the luminance (Ref 104) Flare Formulations... 

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