Is the hottest LCD TV more power efficient than pl

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Is LCD TV more power efficient than plasma

at present, flat panel TV mainly refers to liquid crystal (LCD) TV and plasma (PDP) TV. Compared with traditional picture tube (CRT) TV, flat panel TV has the advantages of high-definition imaging, richer colors, longer service life, light and beautiful appearance, space saving and low radiation. With the continuous innovation of flat panel TV technology and the continuous reduction of cost, it will become the first choice for consumers in the future

the flat-panel TV market is developing so rapidly. Although its performance is excellent, it is expected to reach 70.8 million tons in 2020, which is related to the hype of many businesses. "HD", "big screen", "digital", "thin", "XXX million colors" and so on, how many consumers really understand flat-panel TVs under these beautiful words? Today's flat-panel TVs are constantly innovating. How many are truly healthy, environmentally friendly and energy-saving TVs behind the larger and larger screens, higher and higher resolutions, more stable performance and lower and lower prices

when consumers are immersed in the enjoyment of large screen, they are also bearing higher electricity charges. Therefore, choosing a flat panel TV with excellent performance and energy saving is the right way. Then who is more energy-saving between plasma TV and liquid crystal TV? Let's make a comparison:

lcd LCD TV working principle

liquid crystal panel is based on liquid crystal materials. Because liquid crystal is between solid and liquid, it not only has solid crystal optical properties, but also has liquid flow properties. When powered on, the liquid crystal arrangement becomes orderly, making it easy for light to pass through; The arrangement is disordered when there is no electricity, preventing the light from passing through

the liquid crystal panel consists of two rather delicate sodium free glass materials with a layer of liquid crystal sandwiched between them. When the light beam passes through this layer of liquid crystal, the liquid crystal itself will stand in rows or twist in an irregular shape, thus blocking or making the light beam pass smoothly. Most liquid crystals are organic compounds composed of long rod-shaped molecules. In the natural state, the long axes of these rod-shaped molecules are roughly parallel. Pour the liquid crystal into a well processed slotted plane, and the liquid crystal molecules will be arranged along the slots. Therefore, if those slots are very parallel, the molecules are also completely parallel

lcd is composed of two polarization filters that are perpendicular to each other, so under normal circumstances, all the light trying to penetrate should be blocked. However, since the twisted liquid crystal is filled between the two filters, the light will be twisted 90 degrees by the liquid crystal molecules after passing through the first filter, and finally pass through the second filter. On the other hand, if a voltage is applied to the liquid crystal, the molecules will rearrange and be completely parallel, so that the light is no longer twisted, so it is just blocked by the second filter. In a word, power on blocks the light, and no power on makes the light emitted. Therefore, the liquid crystal molecules will not consume energy during the use of the TV, and the applied voltage will. However, this is not the main aspect of the energy consumption of the liquid crystal TV, but the backlight

the liquid crystal itself does not show color and light, so where do we get the image from the liquid crystal screen? In fact, the LCD panel is a passive display device, which cannot emit light by itself, and can only display images through the illumination of the light source. At present, most LCD TVs use cold cathode fluorescent tubes as backlight. The cold cathode fluorescent lamp tube is filled with inert gas and a small amount of mercury, and the inner wall of the glass tube is coated with phosphor. When the voltage is increased to the electrodes at both ends of the tube, the two poles begin to discharge, and the Mercury will be activated due to the collision of electrons or atoms of the charged inert gas, emitting ultraviolet light, which activates the phosphor to emit light. After long-term continuous improvement, the current cold cathode fluorescent tube technology has been very mature, with long service life and excellent performance in brightness, power saving, etc. Cold cathode fluorescent tubes are tubular light sources. In order to make the brightness of different areas of the screen uniform, a large number of accessories are required

tft LCD TV working principle

the image of liquid crystal depends on the lamp on the back of the liquid crystal panel to form an image through the liquid crystal panel. The brightness has always been a big problem that puzzles the liquid crystal TV. There are two ways to improve the brightness: one is to improve the light passing rate of the liquid crystal panel, but this is limited. Second, the technology of multiple light tubes is adopted, which greatly improves the brightness. Under the same parameters, the brightness effect of liquid crystal is better. However, another problem arises. More cold cathode fluorescent tubes mean increased power consumption. In particular, large screen LCD TVs usually need dozens of cold cathode fluorescent tubes, which is bound to increase power. The power of 21 inch LCD TV is about 40W, and that of 30 inch LCD TV is about 120W. The larger the size, the higher the power consumption

tft LCD TV working principle

the principle of plasma TV consists of numerous plasma display units. The structure of plasma display units is similar to that of fluorescent lamps. The difference is that electrodes replace filaments to create electric fields, inert gases replace mercury, and upper and lower glass substrates replace fluorescent lamp tube walls

plasma display units on the plasma screen

as shown in the figure, the plasma display unit is composed of front and rear glass substrates. The front panel glass is provided with transparent ITO electrode and bus electrode to enhance ITO conductivity, and the electrode is covered with transparent dielectric layer and magnesium oxide protective layer, mainly to protect the electrode from the loss caused by discharge impact. The rear panel glass is provided with a data electrode, a dielectric layer and a strip-shaped partition layer, and red, green and blue fluorescent materials are printed in each partition layer. After vacuumizing between the upper and lower substrates, the thin mixed gas is encapsulated

when the electrode is powered on, the electrons between the two electrodes escape to form a current. The electric field will excite the inert gas into a plasma state. The inert gas in the plasma state collides with the electrons to produce ultraviolet light. The ultraviolet light will excite the red, green and blue phosphors to emit light, thus producing corresponding colors

working principle of PDP TV

here we can see the difference between plasma TV and LCD TV in light-emitting mode. Plasma TV adopts the active light-emitting mode, and each small pixel is emitting light. Although the power consumption of each plasma display unit is very low, the consumption of so many plasma display units together is also very large. When the inert gas is excited into the plasma state, it needs to absorb energy. In addition, the inert gas has important practical significance and far-reaching historical significance. In the process of generating ultraviolet light by collision with electrons, it is inevitable to generate heat, which is not used by the display process and is lost in vain, which also increases the power of the plasma TV

the same as the LCD TV, the power of the plasma TV is also increasing with the increase of the screen, but the increase is the plasma display unit rather than the cold cathode fluorescent tube. Plasma TV consumes a large amount of power and is known as the king of high energy. In summer, it is even popular to say that it is like an oven. However, with the continuous development and improvement of plasma technology in recent years, it has been greatly improved in this regard

power saving competition: LCD PK plasma

take the management station data of several companies for example, they are the representative manufacturers in the field of LCD TV - Samsung, Sony and sharp, and the representative manufacturers in the field of plasma TV - Hitachi and Panasonic. By comparing the official data, it is found that among the flat-panel TVs of about 45 inches, the users of plasma TVs can choose the appropriate specifications according to the product test requirements, and the power is lower than that of LCD TVs. However, it is undeniable that the temperature of the LCD screen is lower than that of the plasma when it works

which of LCD TV and plasma TV consumes more power? If both the LCD and plasma screens display white, let the same small pixels glow to the peak. If the same is a 42 inch TV, the plasma TV will consume more power. Because the LCD TV is passive, there is a backlight behind it. After the LCD panel is turned on, there are cold cathode fluorescent tubes behind it, which are always on. By changing the voltage value stimulating the LCD, the light intensity and color can be controlled, and then the color combinations with different depths can be changed on the LCD panel. The power will not change because of the display effect

plasma TV is an active light-emitting device. Each small pixel is emitting light, and its power is related to the number of light-emitting times, brightness, etc. in the case of all white, each plasma display unit reaches the peak. At this time, the power consumption of plasma TV is higher than that of LCD TV. However, there are white and black images on the TV, and there is no light on the black picture. At this time, the power consumption is only 30-40% of that of all white. Considering the balance, in practice, the focus is on a certain period of time. Panasonic and sharp have made a comparison of power consumption, which should be said to be basically the same; Or plasma TVs save a little electricity. At peak power consumption, plasma TV consumes more power. But from a dynamic point of view, the power consumption of plasma TV is not necessarily higher than that of LCD TV. Professor larryweber, one of the inventors of PDP, made the following statement on sid2004: "In terms of power consumption, although PDP TV is worse than LCD TV in the case of maximum brightness display, when playing ordinary TV images, although it is not obvious, the power consumption of PDP TV is lower. This is because when playing such images, the power consumption of self luminous PDP TV is only about 20% of that in the case of maximum brightness display, and the power consumption of LCD TV has nothing to do with the image, and the backlight must be turned on, so the power consumption has been very large."

at the American International Consumer Electronics Show (CES) in January this year, Canon and Toshiba jointly launched a new generation of SED (surface conduction electron emission display) TV after the end of the copper molybdenum mine strike in Peru. The 36 inch sedtv displayed on the scene consumes 133 watts, while the 37 Inch LCD TV consumes 199 watts and the plasma TV 370 watts. From this perspective, It seems that LCD TV has the upper hand in the battle with plasma TV

through years of improvement in the structure of discharge chamber, gas formula, electrode shape and driving circuit, the luminous efficiency of PDP has increased from 1.2lm/w in the early years to 1.8lm/w in the previous two years, and then to 2.5lm/w now, reducing the power consumption of 42 inch PDP from more than 400 watts to more than 200 watts. The goal is to increase the luminous efficiency to 5lm/w and reduce the power consumption of 42 inch PDP to more than 100 watts. The luminous efficiency of LCD TV and fluorescent tube is 30 ~ 100 lumens/watt. The luminous efficiency of CCFL backlight tube of large screen LCD TV can be 50 ~ 60 lumens/watt, which is more than 20 times that of PDP. However, after the display screen is assembled, the overall backlight utilization rate is only about 5%, which is not much less than that of plasma TV. (end)

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