Television History
History of television
In its early stages of development, television employed a combination of optical, mechanical and electronic technologies to capture, transmit and display a visual image. By the late 1920s, however, those employing only optical and electronic technologies were being explored. All modern television systems rely on the latter, although the knowledge gained from the work on mechanical-dependent systems was crucial in the development of fully electronic tv’s.
The first time images were transmitted electrically were via early mechanical fax machines, including the pantelegraph, developed in the late 1800s. The concept of electrically-powered transmission of television images in motion, was first sketched in 1878 as the telephonoscope, shortly after the invention of the telephone. At the time, it was imagined by early science fiction authors, that someday that light could be transmitted over wires, the same as sounds.
The idea of using scanning to transmit images was put to actual practical use in 1881 in the pantelegraph, through the use of a pendulum-based scanning mechanism. From this period forward, scanning in one form or another, has been used in nearly every image transmission technology to date, including television. This is the concept of “rasterization”, the process of converting a visual image into a stream of electrical pulses.
In 1884 Paul Gottlieb Nipkow, a 20-year old university student in Germany, patented the first electromechanical television system which employed a scanning disk, a spinning disk with a series of holes spiralling toward the center, for rasterization. The holes were spaced at equal angular intervals such that in a single rotation the disk would allow light to pass through each hole and onto a light-sensitive selenium sensor which produced the electrical pulses. As an image was focused on the rotating disk, each hole captured a horizontal “slice” of the whole image, in a scanning fashion.
Nipkow’s design would not be practical until advances in amplifier tube technology became available in 1907. Even then the device was only useful for transmitting still “halftone” images – represented by equally spaced dots of varying size – over telegraph or telephone lines. Later designs would use a rotating mirror-drum scanner to capture the image and a cathode ray tube (CRT) as a display device, but moving images were still not possible, due to the poor sensitivity of the selenium sensors.
Scottish inventor John Logie Baird demonstrated the transmission of moving silhouette images in London in 1925, and of moving, monochromatic images in 1926. Baird’s scanning disk produced an image of 30 lines resolution, just enough to discern a human face, from a double spiral of lenses. Remarkably, in 1927 Baird also invented the world’s first video recording system, “Phonovision” — by modulating the output signal of his TV camera down to the audio range he was able to capture the signal on a 10-inch wax audio disc using conventional audio recording technology. A handful of Baird’s ‘Phonovision’ recordings survive and these were finally decoded and rendered into viewable images in the 1990s using modern digital signal-processing technology.
In 1926, Hungarian engineer Kálmán Tihanyi designed a television system utilizing fully electronic scanning and display elements, and employing the principle of “charge storage” within the scanning.
Choosing a TV can be hard, but look similar, but the flat screen and thin profile is where the the two different camps of flat-panel display standard will, of course, gladly spruik the advantages of their own standard and the deficiencies of the other. But which type of display, plasma or LCD, is better? And which will give you more bang for your buck for getting the best choice of your new plasma-television albeit plasma lcd, television plasma flat panel,tv plasma hdtv, lcd televisions, lcd tv plasma tv,42inch or 50inch the same questions are often asked.Plasma and LCD technology — what’s the difference?
Plasma and LCD panels may look similar, but the flat screen and thin profile is where the similarities end. Plasma screens, as its name suggests, uses a matrix of tiny gas plasma cells charged by precise electrical voltages to create a picture. LCD screens (liquid crystal display) are in layman’s terms sandwiches made up of liquid crystal pushed in the space between two glass plates. Images are created by varying the amount of electrical charge applied to the crystals. Each technology has its strengths and weaknesses, as you’ll read below.
54-inch Panasonic plasma a great value for getting the best of your new plasma-television “Which are the best”.
For some people, a 50-inch HDTV just isn’t big enough. Panasonic created its new 54-inch screen size, represented by the TC-P54G10, for just those kinds of people. In our testing, the plasma proved every bit the equal of its smaller brothers in the company’s G10 series, which remains one of the best values for shoppers who prize picture quality.
LCD Plasma-television Reviews – the same question apply “Which are the best”. Both types of flat-panel TVs — plasma and LCD — are thin and wall-mountable, but each has different advantages. In general, plasma TVs can achieve deeper black levels. LCD televisions are generally brighter than plasma TVs, meaning they are easier to watch in a well-lit room, and many can double as a computer monitor or media-center display.
To the best of your new plasma-television .Although flat LCD HDTVs used to be restricted to sizes smaller than 32 inches, LCD TVs up to 55 inches are now common, and larger sizes are available. LCD TV reviews also indicate that black levels have improved (although most are still not quite up to the level of plasma). In the past, plasma TVs had been less expensive than LCD TVs, but that gap has now largely disappeared. Since LCD TVs are available in such a wide size range, it’s easier to find a television that matches your budget. See our companion report on plasma TVs for more flat-screen options. Rear-projection TVs give you an even larger screen, but they aren’t as thin and are not wall-mountable, and very few models are still being made Getting the best of your new plasma-television results from knowledge gained by reading reviews.
The History of Plasma Display Panels
“For most of its time, it was a solution looking for a problem,” says Larry Weber of the technology he has dedicated his professional life to. Today that “solution”—the amazing plasma display panel, invented at the University of Illinois in 1964—seems to have finally found the problem (not to mention the goldmine) it always deserved: carrying high-definition television (HDTV) into millions of homes.
Weber’s 60-inch plasma display, a prototype he developed for Matsushita (bearing the Panasonic label), combines the large size and superb resolution necessary for HDTV with the convenience of thinness. You can even hang it on your wall. In fact, one of these marvels hangs on the wall of Weber’s upstate New York company, Plasmaco, an R & D arm of Matsushita. When you see it, you’ll know why the Society for Information Display gave Weber its highest award in 2000 for his contributions to plasma displays.
And you’ll begin to understand why the TV industry gave a 2002 Emmy award for technological achievement to the original U of I inventors of the plasma display: Weber’s old teachers Donald Bitzer and the late Gene Slottow and their first graduate student, Robert Willson , whose name appears alongside those of Bitzer and Slottow on the original plasma display patent. Fujitsu, the leading manufacturer of plasma displays, also shared the award.