Color-from-blue approach

The simulation discussed above was based on full color produced by individual red, green, and blue emitters. Other full-color reproduction approaches have been proposed for OLED displays including color from blue emitter by means of energy down conversion fluorescent filter [177], and color from white emitters by means of transmission color filter sets similar to that used in LCD industry [178,179]. Table 1.5 compares the EL efficiency of equivalent white... 

Abstract Mononuclear Ir(III)-polyimine complexes show outstanding luminescence properties, i.e., high intensities, lifetimes in the is time range, and emission wavelengths that can be tuned so as to cover a full range of visible colors, from blue to red. We discuss the approaches for the use of ligands that afford control on luminescence features. Emphasis is placed on subfamilies of cyclometalated complexes, whose recent enormous expansion is motivated by their potential for applications, including that as phosphorescent dopants in OLEDs fabrication. The interplay of the different excited states associated... 

Benedict s solution is heated, when the temperature approaches boiling point, the color of the mixture changes from blue to green-yellow or orange. A brick red precipitate of copper(I) oxide is then formed. 

Blue Large-Area EL Devices Covered with Filters and Appropriate Dye Layers That Convert the Blue EL Emission into the Required Emission Color. One of the most promising methods for the production of flat color screens is the use of blue PLEDs covered with dye layers to convert the EL emission into the RGB colors and, if necessary, with filters to purify the emission light [171-174] (see Fig. 30.20). In principle, the internal quantum efficiency of this technique for color conversion from blue into any other emission color can approach 100%. 

Other Color Order Systems. The Natural Color System (24), abbreviated NCS, developed ia Sweden is an outgrowth of the Hesselgren Color Adas, and uses the opponent color approach. Here colors are described on the basis of their resemblances to the basic color pairs red-green and blue-yeUow, and the amounts of black and white present, all evaluated as percentages. Consider a color that has 10% whiteness, 50% blackness, 20% yellowness, and 20% redness note that the sum is 100%. The overall NCS designation of this color is 50, 40, Y50R iadicating ia sequence the blackness, the chromaticness (20 + 20), and the hue (50% on the way from yellow to red the sequence used is Y, R, G, B, Y). 

Nanometals have interesting optical properties [37,73,74]. For example, suspensions of nanoscopic Au particles can be pink, purple, or blue depending on the diameter of the particles [74]. These colors arise from the plasmon resonance absorption of the nanometal particle, a phenomenon we have explored in some detail [37,73]. We have shown that membranes containing Au nanowires like those described here also show this plasmon resonance band, and as a result such membranes can show a wide variety of colors. This absorption in the visible region provides an interesting optical approach for characterizing the Au nanowire-containing membranes. 

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