Vacuum-Based Displays

Vacuum-based displays ultimately were unable to fulfiU the growing needs of the computer industry for a lightweight, low-power portable display that was less than an inch thick. It took the sohd-state revolution in electronic materials to identify candidates that could truly fill the needs of such devices. An early effort in electroluminescence was translated into hght-generating matrix displays such as the one shown in Fig. 7.16. The matrix itself is an array of pixels, each of which is a capacitor structure built of thin films vacuum-deposited... 

Note the rare earth based compositions are not represented. None of these phosphors, except the ZnO Zn composition have been entirely adequate. It is, perhaps, for this reason that this display has become nearly obsolete. With the advent of flat panel displays such as the computer controlled plasma display or the back-lighted liquid-crystal displays (which we will describe later), the vacuum fluorescent display has been largely superseded. Such computer controlled displays can show the item purchased, the amount of the sale and keep a running total for the buyer. 

CNT electron sources were thought to have their largest potential market in flat-panel field-emission displays (FEDs) [320,321], In 2011 the flat-panel display market had an estimated net worth in excess of 135 billion—one of the largest global markets in human history. Figure 5.26(g) illustrates a simple CNT-based display pixel, where the CNTs are vertically deposited on a matrix of electrodes in a vacuum housing. 

The reduction in cavity volume improves vacuum quality, display lifetime, and stability. The insets show typical RGB phosphor masks for each technology. Adapted from [136,325]. (h) An optical micrograph of Samsung s CNT-based full-color, 100 Hz, prototype 38-in. (diagonal) FED display. 

The display technologies traditionally employed in these applications are LCDs, vacuum fluorescence displays, and inorganic LEDs. Industrial soiu-ces estimate that hy 2004-2005, organic LEDs (including PLEDs as well as LEDs based on small organic molecules) may capture between US 350 to US 700 million of that market (3,35). In the long run, PLEDs also have the potential to replace current high resolution video-rate displays in, eg, desktop monitors, ultrathin television sets, and the like. 

Electronic displays are the connection between human beings and communication systems. Glass has played a key role in the development of such displays, first with vacuum-based cathode-ray tubes (CRTs) and then with solid-state flat panel displays (FPDs). 

Although television dates back to 1927 and was highly publicized during the 1936 Olympics, it was not until post-World War II prosperity that vacuum-tube-based television products reached the mass consumer market. The initial scries of televisions manufactured during the 1950s had screen displays that made the viewer... 

From this display it can be seen that a 0.1 /lb increase in naphtha price from 1.0 to 1.1 / lb would raise the ethylene production cost from 2.5 to 2.8 /lb. If such a movement did occur, heavy gas oil at current 0.75 /lb levels (based on equivalent heavy fuel oil adjusted for viscosity considerations and vacuum distillation costs) would become competitive with naphtha. 

Experimental data are obtained using a Vacuum Generators ESCA III spectrometer equipped with a dual Al/Ag X-ray source. The base pressure is 10 1 mbar in the spectrometer. A1 depositions are made in the attached preparation chamber with a residual pressure in the 10" mbar range, by thermal evaporation or sputtering as displayed in Figure 1. 

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