A television is an electronic facility for receivingtelevision signals, usually consists of a displayand controls or controls.
Its operation is based on the phenomenon ofphotoelectricity, which is responsible for converting light into electricity in a camera thatcan transmit high-frequency wave to thereceiving antennas and reproduce on the screen of our television . The TV is one of the mosteveryday appliances.
Its operation is based on the phenomenon ofphotoelectricity, which is responsible for converting light into electricity in a camera thatcan transmit high frequency waves to thereceiving antennas and is reproduced on the screen of our television . The TV is one of themost everyday appliances.
Screen
Thanks to advances in display technology, there are now several classes in modern TVs:
Cathode ray tube or CRT: The most common displays are direct-view tubes are achieved with up to 37 inches diagonal. Until 2007, are still the least expensive, and it is a mature technology that can deliver a great picture. Since we do not have a fixed resolution, although a minimum resolution, given the separation between points, can display fonts in various resolutions with the best possible image quality. The frame rate of NTSC TV is 29.97 Hz and 25 Hz in the case of the PAL standard TVs. Visible vertical resolution of the TV is 480 lines NTSC, PAL and the 575-lines. Cathode ray tubes were quite bulky and heavy, are currently being replaced by formats Plasma, LCD and more recently LED.
Projection: They are large-screen TVs up to 100 diagonal inches or more. Uses three types of projection systems: CRT, LCD and DLP (chip micromirror device). Rear-projection TVs have existed since the 70's, but at that time had no common definition of a television cathode ray.Current models are much improved, and offer a large price. Projection screens do not give good results in the light of day or in brightly lit rooms, making them more suitable for darkened areas.
Liquid crystal display and plasma: The current developments allow the manufacture of flat panel TVs using liquid crystal technology for active matrix (LCD) or plasma. They are ready for high definition (1920x1080) pixels, although some have less resolution. These televisions can have only a couple of inches wide, and can be hung on a wall like a painting or be put on base.Some models can also be used as computer monitors. LCD flat screens can have narrow viewing angles, and are less suitable for the home, although this is being addressed in most current computers.
LED Matrix has become one of the options for video outdoors and in stadiums, since the advent of light emitting diodes and their respective circuits ultraluminous. The LED displays allow you to create scalable ultragrandes currently existing technologies that can not igualar.Recientemente has taken the initiative to apply this technology to the domestic TV. They take on different characteristics to other types of display. Lower power consumption compared to LCD screens, improved durability, reduced thickness of the same and higher contrast are examples of these features. The pioneer in this field was Korea's Samsung commercial.
http://es.wikipedia.org/wiki/Televisor
In this process, the light from outside is broken down into three components: red, blue and green. Next is to convert light rays captured by the camera into electrical signals called "Video".After obtaining video signals are sent to the receiver by some form of modulation. Finally, we must send each signal to its corresponding barrel, that is, the signal from the red light component will be sent to red canyon, and so do the signals from the blue light component and the component green light from the image to be reproduced. Parallel to this process is the transmission of the signal light component corresponding to the black-white image, in order to be displayed also in black and white monitors who are not prepared for reproduction in color.Currently there are several systems used to perform the transmission of video signals, such as NTSC, PAL or SECAM .. However, all will be compatible with each other because, otherwise, would be quite uncomfortable, if not unfeasible, the marketing of television where they could only reproduce images captured by the system. The same happens with the TV in color should occur with black and white. There must be a full compatibility to view images captured in black and white on a color monitor and be able to view images captured by a system of color in a black and white monitor, although obviously in the latter case, the images will be seen in black and white. The idea, therefore, is that the information contained in the video signal must be identical in color and black and white as well as profitable in both types of receptor. The color signal, called "chroma signal or chromium," will be used only in the recipient of color, while white and black, called "video luminance signal" will be used both in color monitors and in white and black.
http://www.angelfire.com/al2/Comunicaciones/Sistemas/tv22.html
Cathode ray tube or CRT: The most common displays are direct-view tubes are achieved with up to 37 inches diagonal. Until 2007, are still the least expensive, and it is a mature technology that can deliver a great picture. Since we do not have a fixed resolution, although a minimum resolution, given the separation between points, can display fonts in various resolutions with the best possible image quality. The frame rate of NTSC TV is 29.97 Hz and 25 Hz in the case of the PAL standard TVs. Visible vertical resolution of the TV is 480 lines NTSC, PAL and the 575-lines. Cathode ray tubes were quite bulky and heavy, and today has developed the Plasma and LCD
Projection: They are large-screen TVs up to 100 diagonal inches or more. Uses three types of projection systems: CRT, LCD and DLP (chip micromirror device). Rear-projection TVs have existed since the 70's, but at that time had no common definition of a television cathode ray.Current models are much improved, and offer a large price. Projection screens do not give good results in the light of day or in brightly lit rooms, making them more suitable for darkened areas.
Liquid crystal display and plasma: The current developments allow the manufacture of flat panel TVs using liquid crystal technology for active matrix (LCD) or plasma. They are ready for high definition (1920x1080) pixels, although some have less resolution. These televisions can have only a couple of inches wide, and can be hung on a wall like a painting or be put on base.Some models can also be used as computer monitors. LCD flat screens can have narrow viewing angles, and are less suitable for the home, although this is being addressed in most current computers.
