Cathode ray tubes, CRTs

In colored cathode ray tubes (CRTs), such as those used in televisions and computer terminals, three electron gun beams are focused on three different sets of phosphor dots on the front face of the tube. The dots are produced by using a compHcated photoHthography process. The phosphor dots are produced by settling the three different phosphors, each of which emits one of the primary saturated colors, red, green, or blue. Each phosphor is deposited separately and the three dots in each set are closely spaced so that the three primary colors are not resolved at normal viewing distances. Instead the viewer has the impression that there is only one color, the color achieved when the three primary colors are added together. 

Phototypesetting represented an easier way to compose type. Eady phototypesetters used an optical process, whereby a disk of characters, ia different sizes and typefaces, was spun under computer control. Each character was projected ia turn onto photosensitive film or paper. This was followed by systems where characters drawn on a cathode ray tube (CRT) exposed the photosensitive material. In each case, the operator iateracted with the system at a video screen that only showed the characters of the text (the iaformation content) and codes that iadicated how the characters were to look on paper. An experienced operator was required to obtain high quaUty results. 

Monitors. Cathode ray tube (CRT) monitors ate a key element of electronic prepress systems, providing an electronic canvas for the operator. They may also be used to judge general adequacy of color in a process called soft proofing. 

Uses. The main appHcation for strontium is in the form of strontium compounds. The carbonate, used in cathode ray tubes (CRTs) for color televisions and color computer monitors, is used both in the manufacturing of the glass envelope of the CRT and in the phosphors which give the color. 

Most monitors are display terminals that use cathode-ray tube (CRT) displays, which function by exciting a layer of phosphors with an electron gun. These devices include monitors used with PCs and terminals used with mainframes or minicomputers. Features such as color, resolution, and size influence power requirements. Most PC monitors are... 

Lead (Pb) is used for many applications, for example in electronic goods such as cathode ray tube (CRT) televisions and as a stabilizer in PVC. Pb is one of the oldest known and most studied occupational and environmental toxins. Despite the many studies, there is still debate regarding the toxic effects caused by Pb [39]. 

It is worth summarizing at this point the different excitation methods used for phosphors that will be referred to throughout this chapter. There are three types photoluminescence (PL) which is based on initial excitation by absorption of light, cathodoluminescence (CL) which is based on bombardment with a beam of electrons, as in a cathode ray tube (CRT) and electroluminescence (EL) which is based on application of an electric field (either a.c. or d.c.) across the phosphor. 

The secondary electrons emitted from the sample are attracted to the detector by the collector screen. Once near the detector, the secondary electrons are accelerated into the scintillator by a positive potential maintained on the scintillator. Visible light is produced by the reaction of the secondary electrons with the scintillator material. The emitted light is detected by a photomultiplier tube, which is optically coupled to the scintillator via a light pipe. The PMT signal is then transferred to the grid of a cathode ray tube (CRT). Data collection... 

The field emission display held a particular fascination for this field, because of its potentially large market [36,44-49]. Field emission displays (FEDs) are flat panel displays, which are a flat panel equivalent of the cathode ray tube (CRT), but in which each pixel is addressed by its own electron beam from a field emitter, rather than having a beam scanned across it as in the CRT (Fig. 13.8) [44]. The emitters can be diode or triode type. The triode type is the most elegant, the diode type is lower cost. 

To eliminate the need for recalibration during a measurement and to obtain additional information, the Royco instrument was supplemented with a Nuclear Data ND-60 Multichannel Analyser (MCA). The amplified signal of the Royco 225 (which is proportional to the cimount of light scattered from each particle) was connected to the input of the MCA which cem count and classify pulsed input signals into as many as 2048 channels and display the results on a cathode ray tube (CRT). This number of cells is of course much more than required to determine the PSD. The data were therefore grouped into eleven cells whose limits were consistent with those used earlier (5), emd the counts in these cells were then printed on a Texas Instruments 743 KSR Data Terminal interfaced with the MCA. 

There are not many uses for dysprosium. Scientists continue to experiment with it as a possible alloy metal (it has a high melting point) to be mixed with steel to make control rods that absorb neutrons in nuclear reactors. There are only a few commercial uses for dysprosium, such as a laser material and as a fluorescence activator for the phosphors used to produce the colors in the older TV and computer cathode ray tubes (CRTs). When combined with steel or nickel as an alloy, it makes strong magnets. 

Cathode ray tubes (CRTs) are almost universally used in colour televisions and still dominate in the display monitors of desktop computers. They are obviously not suitable for laptop PCs, because of bulk and weight, where currently liquid crystal displays are the systems of choice. Neither are they the most suitable technology for very large area displays, where other display techniques such as plasma panels and electroluminescent devices offer advantages. 

Recycling of computer monitor or television cathode ray tubes (CRT) or other lead-contaminated glass... 

The green as well as the blue transparent cobalt pigments are used as filter materials for cathode ray tubes (CRT) [5.279]. 

Field operating personnel have access to the computer through a man-machine input/output (I/O) system located in the Field office. The I/O equipment consists of a cathode ray tube (CRT) with attached keyboard, a card reader and a printer for permanent copy of transmitted information. The I/O system supplies all alarms and operating data needed to monitor production operations. 

The color tube of the television that we use at our home is simply a vacuum tube, or cathode ray tube (CRT). CRT s are frequently used in televisions, computer monitors or anywhere where it is necessary to produce a picture. 

The most familiar display is a television or visual display unit associated with a computer. Both are based on the mature cathode ray tube (CRT) technology, whereby an electron beam selectively activates red, green, and blue (RGB) inorganic phosphors. It is an emissive technology and therefore produces bright images. 

Today, neither household nor office is conceivable without LCDs. They are flat, lightweight, low in energy consumption, and transportable, and continue to displace older technologies such as cathode ray tubes (CRT). After all, a flat television that hangs on the wall like a painting is highly desirable - especially in the living rooms of East Asian cities where space is often in short supply. In fact, surely an LCD TV would be better than a bulky TV set in any room anywhere ... 

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