PC monitor is a significant device of a computer even though the computer was invented without the monitor. The monitor display images generated from the output of computers, which make more convenience for users to communicate with the computer. Until today, the monitor evolves slowly from CRT to LCD and the newer one, Plasma. The old style monitor, CRT, becomes extinct and replaced by LCD and Plasma. However, who knows the LCD was first studied almost ten years before the CRT. According to the article of Wikipedia, the free encyclopedia website, in 1888 Friedrich Reinitzer discovers the liquid crystalline nature of cholesterol extracted from carrots and published his findings at a meeting of the Vienna Chemical Society on May 3, 1888. On the other hand, the German physicist, Ferdinand Braun, invented the CRT in 1897.
A liquid crystal display (LCD) is an electro-optical amplitude modulator realized as a thin, flat display device made up of any number of color or monochrome p
ixels arrayed in front of a light source or reflector. It is often utilized in battery-powered electronic devices because it uses very small amounts of electric power. Nevertheless, the LCD was studied first time in 1888 as the liquid crystalline of cholesterol. It was studied continually until the year 1964, George H. Heilmeier, working on the effect discovered by Williams realized the switching of colors by field-induced realignment of dichroic dyes in a homeotropically oriented liquid crystal. Practical problems with this new electro-optical effect made Heilmeier to continue work on scattering effects in liquid crystals and finally the realization of the first operational liquid crystal display based on what he called the dynamic scattering mode (DSM). Then the UK’s Royal Radar Establishment at Malvern undertook pioneering work on liquid crystals in the late 1960s. Next, on December 4, 1970, the twisted nematic field effect in liquid crystals was filed for patent by Hoffmann-LaRoche in Switzerland. Hoffmann-La Roche then licensed the invention to the Swiss manufacturer Brown, Boveri & Cie who produced displays for wristwatches during the 1970s and also to Japanese electronics industry which soon produced the first digital quartz wristwatches with TN-LCDs and numerous other products. In 1971, the company of Fergason ILIXCO produced the first LCDs based on the TN-effect, which soon superseded the poor-quality DSM types due to improvements of lower operating voltages and lower power consumption. After that, the first active-matrix LCD panel was produced in 1972, United States.
The LCD evolved slowly when compared with the CRT. The CRT was studied after about ten years the LCD, but the CRT was available on sale before fifty years the LCD. The cathode ray tube (CRT) is a vacuum tube containing an electron gun (a source of electrons) and a fluorescent screen, with internal or external means to accelerate and deflect the electron beam, used to form images in the form of light emitted from the fluorescent screen. The image may represent electrical waveforms (oscilloscope), pictures (television, computer monitor), radar targets, and others. The earliest version of the CRT was invented by the German physicist Ferdinand Braun in 1897 and is known as the 'Braun tube'. It was a
cold-cathode diode, a modification of the Crookes tube with a phosphor-coated screen. The first version to use a hot cathode was developed by John B. Johnson (who gave his name to the term Johnson noise) and Harry Weiner Weinhart of Western Electric, and became a commercial product in 1922.
The newer technology became another competitor in the monitor market known as Plasma display. The Plasma display panel (PDP) is a type of flat panel display. Many tiny cells located between two panels of glass hold an inert mixture of noble gases. The gas in the cells is electrically turned into a plasma which then excites phosphors to emit light. In the late-1960's graduate student, Larry F. Weber became interested in plasma displays and completed his PhD studies in this area at the University of Illinois. After his graduation in 1975, he joined the university as a research professor and began a period of 15 years of intensive research into plasma displays, filing 15 patents and eventually developing the sustainer power-saving circuit and color plasma panels. In 1983, IBM introduced a 19-inch (48 cm) orange-on-black monochrome display (model 3290 'information panel') which was able to show up to four simultaneous IBM 3270 terminal session. Then in 1992, Fujitsu introduced the world's first 21-inch (53 cm) full-color display. Two years later, the Plasma display panel facing certain death from an onslaught of color LCD displays, Weber demonstrated color plasma technology on the last day of an industry convention in San Jose. Panasonic was interested, and began a joint development project with Plasmaco, which led in 1996 to the purchase of Plasmaco, its color AC technology, and its American factory. In the next year, 1997, Fujitsu introduced the first 42-inch (107 cm) plasma display; it had 852x480 resolution and was progressively scanned. Also in 1997, Pioneer started selling the first plasma television to the public.
In addition, we used the CRT monitor to communicate with the computer in the first age, and then we changed to LCD. Today, we have the Plasma display as another choice for PC monitor. From the information above, the CRT and Plasma have developed in a short period. The market of the CRT and Plasma grow very fast and drop down very fast as well. Conversely, the LCD is the first monitor that has been studied, the developer develop them step by step. Moreover, the market of the LCD grows slowly but stable and threatens the CRT’s and Plasma’s market until the CRT monitor becomes extinct today. Anyway, the Plasma display still holds the big part of market share even though the LCD holds the biggest share. They are in the tight competition. However, the future of the LCD and Plasma display depend on the users and other equipment, they usually chose the one that is compatible with other device they used or maybe they just chose the one they like more.
