How does television work?

TV produces a number of small dots on the screen that, when you can see as a whole, appear to be a picture. Older TVs rely on the cathode tube to make images and work with an analog signal. Since the technology has passed from analogs to digital, plasma and LCD (liquid crystals) of televisions passing from analog to digital, plasma and LCDs (liquid crystals). These TVs are more compact and have sharper images than their cathode counterparts, because they use a thin grid of pixels to create images rather than a vacuum tube.

eyes and brain

Most types of television work from the same basic principle. Small dots of light produced on a television screen called Pixels, Flash according to a particular pattern provided by a video signal. The eyes of a person transmit this pattern to the brain where it is interpreted as a recognizable image. TV set these formulas refresh hundred times per second - faster than the human eye - cOz gives tiluze movement.

cathode beam tube

Cathode-spy (CRT), the oldest version of the television, consists of a vacuum tube with a narrow end and a wide end. The narrow end contains an ion weapon that fires a series of charged particles of electricity. A number of electromagnets lead the particles to specific points at the wide end of the tube, the screen that viewers look at. Phosphory, substances that light up when they are hit by a charged electric particle, annoy the inner surface of the screen. The ion pistol basically spray the image on the screen, similar to the painting of the pistol painting to the surface.

different types of phosphors produce different colors, but only red, blue and green are required for color TV. The use of these colors in different combinations and intensities can create all the colors that the human eye can see. As energy travels from an ion weapon to tphosphorus is filtered to make againThe exact point on the screen needed to create a particular shade. In combination all these colored pixels create a color picture.

The

cathode rays are relatively difficult due to the large amount of glass they contain and relatively inefficient, especially when used on TVs in a large screen. For this reason, new technologies have been developed to create lighter sets with sharper images. In addition, the development of digital broadcast high -resolution signals (HD) has increased larger screens more popular because images were of higher quality. Plasma and LCD TV were created in response.

plasma screen

The

plasma screen television consists of a number of small cells filled with neon and xenon gases. Each cell is associated with an electrode that excites the gases contained in the cell when burning. The gases emit the charge particles, similar to the ion pistol that interact with phosphors that hide the glass inside each cell. Phosphory light up, creating a figÁzka seen on the TV screen. A large number of cells on the plasma screen cause a large number of pixels, which will draw a clearer and clearer image.

Compared to other technologies, plasma TVs produce some of the deepest blacks, which means that the contrast ratio is very high. They also have very high refresh frequencies, so images will not change as they can on other TVs. However, if the image remains static, it may burn on the screen and create a permanent color; This is more common in older plasma TVs and can also occur in CRT screens. Plasma screens can be set so that they are very clear, which requires a lot of electricity. They also tend to be stronger than LCD TVs, albeit much thinner than CRT.

LCD screen

LCD TVs also use cells to create images. But rather than exciting gases like plasma TVs, cells contain a set of red, blue and greenThe filters covered with a layer of liquid Crystals were inserted between two pieces of glass. Depending on the display type, each cell is connected either to electrodes or thin film transistors (TFT) that trigger the necessary cells to create an image. Screens upright backlight-mostly fluorescent lamp cold cathode, so you can see the picture.

While LCDs are very light and thin, they are subject to "dead" pixels where one or more cells on the screen do not change. Looking LCD screens from angle can also reduce image quality. They have a slower time of response than plasma or CRT TVs, so pictures can "ghost" or blur in motion.

Newer versions of LCD TV use light emitting diodes (LED) as a light source than a cold cathode lamp lamps. LED TVs require less electricity than conventional LCD screens and take up even less space. LEDs also generally emit brighter white light, making these screens especially alive.