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The 12864 dot matrix liquid crystal display module (LCM) is an array of 128 columns * 64 rows composed of 128 * 64 LCD dots. Each display point corresponds to a binary number, 1 means bright, 0 means off. The RAM that stores these dot matrix information is called display data memory. To display a certain figure or Chinese character is to write the corresponding dot matrix information into the corresponding storage unit. The dot matrix information of graphics or Chinese characters is of course designed by yourself. The key to the problem is the relationship between the position (row and column) of the display dot on the LCD screen and its address in the memory. Since the drive circuit of most LCD modules is composed of a row driver and two column drivers, the 12864 LCD screen is actually composed of two independent 64 * 64 LCD screens on the left and right, and there is a 512 * 8 on each half bits show data RAM. The left and right half-screen drive circuits and memory are selected by chip selection signals CS1 and CS2, respectively. (In order to simplify the user design, a few manufacturers add a decoding circuit to the module, so that the 128 * 64 LCD screen is a full screen, and only one chip select signal is required.) The position of the display point on the 64 * 64 LCD screen is determined by the line number (line, 0 ~ 63) and column number (column, 0 ~ 63). The address of a storage unit in 512 * 8 bits RAM is determined by the page address (Xpage, 0 ~ 7) and the column address (Yaddress, 0 ~ 63). Each storage unit stores the display information of 8 liquid crystal dots. In order to make the correspondence between the position information of the liquid crystal dots and the storage address more intuitive, the 64 * 64 LCD screen is divided into 8 display blocks from top to bottom, each block includes 8 rows * 64 columns of dot matrix. The 8 rows of dot matrix information in each column constitute an 8-bit binary number, which is stored in a storage unit. (Need to pay attention: the corresponding relationship between the order of binary high and low significant bits and line number is different for different businesses.) The RAM area that stores a display block is called a storage page. That is, the dot matrix information of the 64 * 64 LCD screen is stored in 8 storage pages, each page is 64 bytes, and each byte stores one column (8 rows) of dot matrix information. Therefore, memory cell addresses include page addresses (Xpage, 0 ~ 7) and column addresses (Yaddress, 0 ~ 63). For example, the liquid crystal dot at the position of (20, 30) in the 128 * 64 screen is lit. Since the column address 30 is less than 64, the dot is in the 29th column of the left half of the screen, so CS1 is valid; the row address 20 is divided by 8 to round up 2. Take the remainder and get 4. The page address in RAM is 2 and the sequence number in the byte is 4; so write binary data 00010000 (may also be 00001000, the order of the high and low depends on the manufacturer) to Xpage = 2, The memory cell with Yaddress = 29 lights up the liquid crystal dots on (20, 30).

What is an LCD module The LCD module is simply a screen + backlight assembly. The display part of the LCD TV is the liquid crystal module, and its low temperature is equivalent to the picture tube in the CRT. Other parts include the power supply circuit, signal processing circuit, etc., and of course the casing. The module is mainly divided into screen and backlight components. The two parts are assembled together, but they work independently of each other (ie, the circuits are not related). The principle of the liquid crystal display is that the backlight assembly emits uniform surface light, and the light reaches our eyes through the LCD screen. The function of the screen is to process the light by pixels to display images. Both parts contain a lot of parts, so I won't go into details here. Currently, the best technology is Sharp, followed by Samsung and Sony. LCD panel expertise Usually when we sell LCDs, there are always consumers who ask what level your screen is, everyone may casually say it is A-level, A + -level, in fact, such answers are not professional, if the consumer is professional Of consumers who talked to such sales with disdain, will only go away, if the tenth of the transactions can be completed, the customer has already understood the outside market, and it is just to let you out. At the lowest price, we must be a valuable salesman for LCD sales. Blind low-cost shipments are not excellent salesmen. You only need to convince customers, let customers believe your profession, and your service. success! For conventional panel grading standards, please see: LCD panel grading standards, truly professional panel grading factory standards, see: AU panel grading standards If you want to be a professional LCD salesman, you must have a deep understanding of LCD professional terms. You know more than customers. At least you can't understand the nouns that customers can't say. Below are some of my collection. LCD proper nouns, you can combine the models you sell to understand: LCD panel The liquid crystal panel is the main component of the liquid crystal display, accounting for nearly 80% of the cost of the liquid crystal display. At present, there are not many manufacturers with panel manufacturing technology in the world, only SHARP (Sharp), SANYO (Sanyo), Samsung, LG-Philips, Taiwan `s AUO and other manufacturers have core technology, most LCD displays use their panels To assemble and produce. Ant's experience: We can prove that we encountered some in the sale, the LCD panel was artificially damaged after the sale and changed the screen, the after-sales customer service of the major manufacturers answered (LCD screen + manual replacement of the screen) the charging standard was close to or exceeded a new LCD Cost, let customers understand the importance of LCD screen quality and the importance of three-year free service! Not long ago, we encountered a couple fighting in Danjiangkou, broke the screen, and wanted to change the screen, and the manufacturer's customer service answer was artificial If it is damaged, the charge will be 1,000 yuan. It is recommended that the customer not repair it, sell the circuit board and buy a new one. There is also the example of many customers who have been selling "Stupid Q" brand LCDs for four years before, after using them for one year, the screen is not bright, black, and the lamp glows yellow. Their customer service refuses to repair. Last week we encountered a gray shadow on the VA721 screen of a customer in Ezhou. Because it was free for three years, it was replaced with a new screen for free. The quality and value of the panel are currently divided into three grades: Sanyo and Sharp of Piglet belong to the first grade, which are mostly used in high-end products, such as: EIZO, SONY, ViewSonic (VP, VG series), etc., the price is relatively high; South Korea's Samsung, LG, and Philips belong to the second level, and most of them are used on monitors sold with branded machines; Taiwanese manufacturers such as AUO are in the third position. Chimei and Hanyu Caijing mostly obtain a large number of OEM OEM orders at a cost-effective ratio. According to my understanding, there is also a NEC-SVA (Shanghai Broadcasting and TV) joint venture fifth-generation line panel with particularly good prices. We can see ultra-low prices in the market. Most price models are such panels. Dead pixels The so-called dead pixels are the general term for pixels that cannot be displayed normally on the LCD panel. The liquid crystal panel is composed of many display points, which are completed by the liquid crystal substance on each display point under the control of electric signals to change the light transmission in the same state. At a resolution of 1024 × 768, the LCD panel has a total of 786,432 display points, so many points are difficult to completely guarantee that individual problems will occur. However, at the current level of technology, if the LCD panel with dead pixels is scrapped, it is believed that the LCD display can only be a sky-high commodity in the window. Therefore, the number of dead pixels has become the main basis for panel classification. Manufacturers generally avoid LCD panels by splitting the bad spots, and sell LCD panels with no or few bad spots at a higher price, while those with a larger number of bad spots are sold to small factories at low prices to produce cheap products. The current main grading standards are: Panel manufacturer standards: Korean manufacturers, 3 or less are A-level Japanese manufacturers, 5 or less are A-level Taiwan manufacturers, and 8 or less are A-level manufacturers Key indicators of mainstream LCD monitor brands: AA level: The LCD display without any dead pixels is AA level. Class A: Less than 3 dead pixels, with no more than one bright spot, and the bright spot is not in the central area of the screen. Level B: Less than 3 dead pixels, of which there are no more than two bright spots, and the bright spots are not in the central area of the screen. Ant Tip: The LCD panel has so far not been able to overcome the dead spots and highlights from the process, the general ratio of a little bit to no point is 8: 2; we see the no-bad spot guarantee promised by the dealers, most of them are manufacturers and distribution Some of the products in the business are picked manually, and there is no point to promise to sell to the seller at a high price, while some are sold to the industry order at a low price. Therefore, if you find this model, you should talk to the salesperson and customers. Can meet the requirements of users to pick points, of course, the price should also be controlled, some machines should be cheap (or send gifts) as soon as possible to the Internet cafes and unit customers! Contrast The accessories such as control IC, filter and orientation film used in the manufacture of LCD panels are related to the contrast of the panel. For the average user, a contrast ratio of 350: 1 is enough, but in the professional field, such contrast is not enough. Meet the needs of users. Compared with CRT monitors, it is easy to achieve a contrast ratio of 500: 1 or higher. Only high-end LCD monitors can achieve this level, because contrast is difficult to accurately measure by the instrument, so you have to see it yourself when picking. Little Ant Tip: Contrast is very important, it can be said that it is a more important indicator to select the LCD than the bright spot. When you understand that the LCD that your customers buy is used for entertainment and watching DVDs, you can emphasize that the contrast is more important than no dead pixels. When we look at streaming media, the general source of the film is not very bright, but to see the contrast between the light and dark of the character scene, the texture of the hair from gray to black, it depends on the level of contrast. ViewSonic's VG and VX have always emphasized the contrast index. The VG910S is a 1000: 1 contrast ratio. We compared this with a Samsung dual-head graphics card. The Samsung LCD is obviously comparable. You can try it if you are interested. In the 256-level grayscale test in the test software, you can see more small gray grids when you look up, that is, good contrast! brightness Liquid crystal is a substance between solid and liquid, which cannot emit light by itself. It needs an additional light source. Therefore, the number of lamps is related to the brightness of the LCD. The earliest LCD monitors only had two lamps on the top and bottom. Up to now, the lowest for popular models is four lamps, and the highest is six lamps. The four-lamp design is divided into three placement forms: one is that there is a lamp on each of the four sides, but the disadvantage is that there will be a black shadow in the middle, and the solution is to arrange the four lamps from top to bottom, The last one is the "U" -shaped display, which is actually two lamps produced by the two lamps in disguise. The six-lamp design actually uses three lamps. The manufacturer bends the three lamps into a "U" shape and places them in parallel to achieve the effect of six lamps. Little ant tips: Brightness is also an important indicator. The brighter the LCD, the better it looks from a row of LCD walls. The high-brightness technology we often see in CRT (Sonic is called Gaoliang, Philips It `s called Xianliang, BenQ is called Ruicai.) It is by increasing the current of the shadow mask tube and bombarding the phosphor to produce a brighter effect. Such a technology is generally traded for sacrificing image quality and the life of the display. All Products using this kind of technology are normally bright by default, and they can only be executed by pressing a button. Press 3X to play the game; press again to change to 5X to watch the disc, and he will become confused when he looks at it. To see the text, you have to honestly return to the ordinary text mode, this design is actually to let everyone not use highlighting. The principle of LCD display brightness is different from CRT. They are realized by the brightness of the backlight tube behind the panel. Therefore, the design of the lamp tube is more, the light will be uniform. In the early days, when we sold LCDs, we told others that LCDs were three, so it was a good thing. But at the time, Chi Mei CRV came up with a six-lamp technology. In fact, the three tubes were bent into a "U" shape and became The so-called six lamps; such a six-lamp design, plus the lamp itself is very strong, the panel will see very bright, such a masterpiece is represented by VA712 in ViewSonic; but all the highlighted panels will have a fatal Injury, the screen will leak light. This term is rarely mentioned by most people. I personally think that he is very important. Light leakage refers to the liquid crystal is not black, but white and gray under a completely black screen. Therefore, a good LCD should not just emphasize the brightness, but to emphasize the contrast. ViewSonic's VP and VG series are products that do not talk about brightness and contrast! Signal response time Response time refers to the response speed of the LCD to the input signal, that is, the response time of the liquid crystal from dark to bright or from bright to dark, usually in milliseconds (ms). To make this clear, we need to start with the human eye's perception of dynamic images. There is a "visual residue" phenomenon in the human eye, and the high-speed motion picture will form a short impression in the human brain. Animation, movies, etc. until now the latest game is the application of the principle of visual residue, allowing a series of gradual images to be displayed quickly and continuously in front of the human eye, forming a dynamic image. The acceptable screen display speed is generally 24 frames per second, which is the origin of the 24 frames per second of the movie. If the display speed is lower than this standard, people will obviously feel the pause and discomfort of the screen. According to this index calculation, the display time of each screen needs to be less than 40ms. In this way, for a liquid crystal display, a response time of 40ms becomes a hurdle, and a display of less than 40ms will have a significant "tailing" or "afterimage" phenomenon, which makes people feel chaotic. If you want the image to be smooth, you need to reach 60 frames per second. I used a very simple method to calculate the number of frames per second under the corresponding reaction time as follows: Response time 30ms = 1 / 0.030 = approximately 33 frames per second response time 25ms = 1 / 0.025 = approximately 40 frames per second response time 16ms = 1 / 0.016 = approximately 63 frames per second response time 12ms = 1 /0.012=approximately 83 frames per second response time 8ms = 1 / 0.008 = approximately 125 frames per second response time 4ms = 1 / 0.004 = approximately 250 frames per second response time 3ms = 1 / 0.003 = seconds Approx. 333 frames response time 2ms = 1 / 0.002 = approx. 500 frames per second response time 1ms = 1 / 0.001 = approx. 1000 frames per second Little Ant Tip: Through the above content we have learned the relationship between response time and the number of frames. From this point of view, the shorter the response time, the better. At the time, when the LCD market was launched, the lowest response time was 35ms, which was mainly represented by EIZO. Later, BenQ `s FP series came out at 25ms, and basically could n`t feel it from 33 to 40 frames. The change is 16MS, which displays 63 frames per second to meet the requirements of movies and general games, so until now 16MS is not outdated. With the improvement of panel technology, BenQ and ViewSonic have started a speed battle. ViewSonic starts from 8MS, 4 milliseconds has been released to 1MS, it can be said that 1MS is the end of the LCD speed battle. For game enthusiasts, the speed of 1MS means that the marksmanship of CS will be more accurate, at least psychologically, such customers will recommend VX series monitors. But everyone should pay attention to the grayscale response when selling. The difference between the full-color response text and sometimes the grayscale 8MS and full-color 5MS mean the same thing. Just like when we sold CRT before, we said that the dot distance is .28 It must be said that his is .21, but the horizontal dot pitch is ignored. In fact, the two sides are talking about one meaning. Now LG has recently come up with a sharpness of 1600: 1. This is also a concept hype. Everyone uses Basically, there are only a few screens, and how can only LG be able to achieve 1600: 1, and everyone stays at the level of 450: 1? Speaking of consumers, the meaning of sharpness and contrast is clearly broken. It is like the PR value of AMD, which has no real meaning. Viewing angle The viewing angle of the liquid crystal is a headache. When the backlight passes through the polarizer, liquid crystal and alignment layer, the output light has directionality. That is to say, most of the light is emitted vertically from the screen, so when viewing the LCD from a large angle, you can not see the original color, or even see all white or all black. In order to solve this problem, manufacturers have also started to develop wide-angle technology, so far there are three more popular technologies, namely: TN + FILM, IPS (IN-PLANE -SWITCHING) and MVA (MULTI-DOMAIN VERTICAL alignment). TN + FILM technology is to add a layer of wide viewing angle compensation film on the original basis. This layer of compensation film can increase the viewing angle to about 150 degrees, is a simple and easy method, and is widely used in liquid crystal displays. However, this technology does not improve performance such as contrast and response time. Perhaps TN + FILM is not the best solution for manufacturers, but it is indeed the cheapest solution, so most Taiwanese manufacturers use this kind of technology. Method to build a 15-inch LCD display. IPS (IN-PLANE -SWITCHING, in-board switching) technology, which claims to allow the viewing angle of up, down, left and right to reach a greater 170 degrees. Although the IPS technology increases the viewing angle, using two electrodes to drive the liquid crystal molecules requires greater power consumption, which increases the power consumption of the liquid crystal display. In addition, fatally, the response time of driving liquid crystal molecules in this way will be relatively slow. MVA (MULTI-DOMAIN VERTICAL alignment) technology, the principle is to add protrusions to form multiple viewing areas. The liquid crystal molecules are not completely vertically aligned when they are static. The liquid crystal molecules are aligned horizontally after the voltage is applied so that light can pass through the layers. MVA technology increases the viewing angle to more than 160 degrees, and provides a shorter response time than IPS and TN + FILM. This technology was developed by Fujitsu, and currently Chimei Taiwan (Qili is a subsidiary of Chimei in mainland China) and Taiwan AUO are authorized to use this technology. ViewSonic `s VX2025WM is a masterpiece of this type of panel. The horizontal and vertical viewing angles are both 175 degrees. There is basically no visual dead angle, and it also promises no bright spots. The viewing angles are divided into parallel and vertical viewing angles. The vertical central axis of the center is the center, moving left and right, you can clearly see the angle range of the image. The vertical angle is centered on the parallel central axis of the display screen and moves up and down to clearly see the angle range of the image. The viewing angle is in "degrees". At present, the most common form of labeling is to directly mark the total horizontal and vertical range, such as: 150/120 degrees. The current minimum viewing angle is 120/100 degrees (horizontal / vertical). Below this value is unacceptable, it is best to reach 150/120 degrees or more.

Product Overview: LCD liquid crystal display is the abbreviation of Liquid Crystal Display. The structure of LCD is to place liquid crystals in two parallel glasses. There are many vertical and horizontal small wires in the middle of two glass plates, and the rod crystal molecules are controlled through energization or not. Change direction and refract light to create a picture. It is much better than CRT, but the price is more expensive. product structure: Each pixel of the liquid crystal display consists of the following: a column of liquid crystal molecules suspended between two transparent electrodes (indium tin oxide), and two polarization filters perpendicular to each other on the outside. If there is no liquid crystal between the electrodes, the polarization direction of the light passing through one of the polarization filters will be completely perpendicular to the second polarization plate, and thus be completely blocked. However, if the direction of polarization of light passing through a polarizing filter is rotated by the liquid crystal, it can pass through another polarizing filter. The rotation of the liquid crystal in the polarization direction of the light can be controlled by the electrostatic field, so that the control of light can be achieved. Liquid crystal molecules are extremely susceptible to induced electric charges due to the influence of an applied electric field. A small amount of charge is applied to the transparent electrode of each pixel or sub-pixel to generate an electrostatic field, and the molecules of the liquid crystal will be induced by this electrostatic field to generate an induced charge and generate an electrostatic torsion, which causes the original rotational arrangement of the liquid crystal molecules to change and thus also change. The amount of rotation through the light. Change the angle so that it can pass through the polarizing filter. Some liquid crystal displays turn black under the influence of alternating current, alternating current destroys the spiral effect of the liquid crystal, and after shutting off the electric current, the liquid crystal display screen will become bright or transparent, this kind of liquid crystal display screen is common in the notebook computer and the low-price liquid crystal display screen. Another type of liquid crystal display commonly used in high-definition liquid crystal displays or large LCD televisions is when the power is turned off, the liquid crystal display is opaque. In order to save power, the liquid crystal display uses a multiplexing method. In the multiplexing mode, one end of the electrodes is grouped together, each set of electrodes is connected to one power supply, and the other end of the electrodes are also connected in groups. Each set is connected to a power supply. At the other end, the packet design ensures that each pixel is controlled by an independent power source. The electronic device or the software that drives the electronic device controls the pixel display by controlling the on/off serial of the power supply. The indicators for testing the LCD include the following important aspects: display size, response time (synchronization rate), array type (active and passive), viewing angle, supported colors, brightness and contrast, resolution and screen aspect ratio, And input interfaces (such as visual interfaces and video display arrays). Product principle: The LCD liquid crystal projector is a combination of liquid crystal display technology and projection technology. It utilizes the electro-optical effect of liquid crystals to control the transmittance and reflectivity of liquid crystal cells through circuits, thereby generating different gray levels and up to 16.7 million colors. Beautiful image. The main imaging device of the LCD projector is a liquid crystal panel. The size of the LCD projector depends on the size of the LCD panel. The smaller the LCD panel, the smaller the projector's size. According to the electro-optic effect, liquid crystal materials can be classified into two types of active liquid crystals and inactive liquid crystals, in which the active liquid crystal has high light transmittance and controllability. The liquid crystal panel uses active liquid crystal, and people can control the brightness and color of the liquid crystal panel through the relevant control system. Like liquid crystal displays, LCD projectors use twisted nematic liquid crystals. The light source of the LCD projector is a dedicated high-power light bulb, and the light emitting energy is much higher than that of a CRT projector using fluorescent light, so the brightness and color saturation of the LCD projector are higher than those of a CRT projector. The pixels of the LCD projector are the liquid crystal cells on the liquid crystal panel. Once the liquid crystal panel is selected, the resolution is basically determined. Therefore, the function of the LCD projector to adjust the resolution is worse than that of the CRT projector. According to the number of internal LCD panels, LCD projectors can be divided into single-chip and three-chip LCDs. Most modern LCD projectors use 3-chip LCD panels (Figure 1). The three-chip LCD projector uses red, green, and blue three liquid crystal panels as control layers for red, green, and blue light, respectively. The white light emitted by the light source is condensed into the dichroic mirror group after passing through the lens group. The red light is firstly separated and projected onto the red liquid crystal panel. The image information represented by the transparency under the [record" of the liquid crystal panel is projected into an image. Red light information. The green light is projected onto the green liquid crystal panel to form the green light information in the image. The same blue light passes through the blue liquid crystal panel to generate the blue light information in the image. The three colors of light converge in the prism and are projected by the projection lens. A full-color image is formed on the projection screen. Three-chip LCD projectors have higher image quality and higher brightness than monolithic LCD projectors. LCD projectors are smaller, lighter in weight, simpler in manufacturing process, higher in brightness and contrast, and moderate in resolution. Nowadays LCD projectors occupy a market share of about 70% of the total market share, which is the current market share. The highest and most widely used projector. Features: 1, low voltage micro power 2, small and exquisite appearance, thickness is only 6,5-8mm 3, passive display type (no glare, does not stimulate the human eye, will not cause eye fatigue) 4, shows a large amount of information (because the pixels can be done very small) 5, easy to color (can be very accurate reproduction on the chromatogram) 6, no electromagnetic radiation (safety to humans, conducive to the confidentiality of information) 7, long life (this device has almost no deterioration problem, so the life is extremely long, but the backlight life of the LCD is limited, but the backlight can be replaced) Product Categories: The liquid crystal display can be divided into passive matrix LCD and active matrix LCD according to different control modes. Segmented display and dot matrix display. Segment codes are the earliest and most common display methods, such as calculators and electronic watches. Since MP3 has been developed, dot-matrix formats such as MP3, mobile phone screens, and digital photo frames have been developed. 1, passive matrix Passive-matrix LCDs are greatly limited in brightness and viewing angle, and their response speed is slow. Due to the problem of picture quality, such a display device is not conducive to the development of a desktop display. However, due to a low cost factor, some displays on the market still employ a passive matrix LCD. The passive matrix LCD can be divided into TN-LCD (Twisted Nematic-LCD, Twisted Nematic LCD), HTN-LCD (High Twisted Netamic-LCD, High Twisted Nematic LCD), and STN-LCD (Super TN-LCD). Twisted nematic (LCD) and DSTN-LCD (Double layer STN-LCD, double layer supertwisted nematic LCD). 2, active matrix Currently widely used active matrix LCD, also known as TFT-LCD (Thin Film Transistor-LCD, thin film transistor LCD). The TFT liquid crystal display has built-in transistors in each pixel of the picture, which can make the brightness brighter, the colors more abundant, and the wider viewing area. Compared with CRT displays, the flat display technology of LCD displays is characterized by fewer parts, fewer desktops, and less power consumption, but CRT technology is relatively stable and mature. Product Specifications: 1, visible area The size of the LCD display is the same as the actual screen area that can be used. For example, a 15-inch LCD display is approximately equal to the viewing range of a 17-inch CRT screen. 2, visual angle The viewing angle of the liquid crystal display is symmetric, but the top and bottom are not necessarily symmetrical. For example, when the incident light of the backlight passes through the polarizer, the liquid crystal, and the alignment film, the output light has a specific directional characteristic, that is, most of the light emitted from the screen has a vertical direction. If we look at a completely white picture from a very oblique angle, we may see black or distorted colors. In general, the upper and lower angles are less than or equal to the left and right angles. If the viewing angle is 80 degrees left and right, it means that the screen image can be clearly seen when the screen is at a position of 80 degrees from the normal of the screen. However, due to the different scope of human vision, if you do not stand in the best viewing angle, you will see errors in the color and brightness. Currently, some vendors have developed various wide viewing angle technologies to try to improve the viewing angle characteristics of LCDs, such as IPS (In Plane Switching), MVA (Multidomain Vertical Alignment), and TN FILM. These technologies can increase the viewing angle of the liquid crystal display to 160 degrees or even more. 3, pitch We often ask how big is the dot pitch of the liquid crystal display, but most people do not know how this value is obtained, let us now understand how it is obtained. For example, a typical 14-inch LCD has a viewing area of 285, 7mm x 214, and 3mm. Its maximum resolution is 1024 x 768, so the dot pitch is equal to: visible width/horizontal pixels (or visible height/vertical pixels ), ie 285, 7mm/1024=0, 279mm (or 214, 3mm/768=0,279mm). 4, color degree The important color of LCD is of course the degree of color expression. We know that any color in nature is composed of three basic colors: red, green, and blue. The LCD panel is composed of 1024×768 pixels. Each independent pixel color is controlled by three basic colors of red, green, and blue (R, G, and B). The liquid crystal display produced by most manufacturers, each basic color (R, G, B) reaches 6 bits, that is 64 degrees of expression, then each individual pixel has 64×64×64=262144 colors. Many manufacturers also use the so-called frame rate control (FRC) technology to display full-color images in an emulated manner. That is, each basic color (R, G, B) can reach 8 bits, that is, 256 performance degrees. , then each individual pixel has up to 256×256×256=16,777,216 colors. 5, the contrast value The contrast value is the ratio that defines the maximum brightness value (all white) divided by the minimum brightness value (all black). CRT displays typically have contrast ratios as high as 500:1, so that rendering a true black screen on a CRT monitor is easy. However, it is not easy for the LCD. The backlight formed by the cold cathode ray tube is difficult to perform fast switching operations. Therefore, the backlight is always on. In order to get a full black picture, the liquid crystal module must completely block the light coming from the backlight, but in terms of physical characteristics, these components cannot fully meet this requirement, and there will always be some light leakage. In general, the acceptable value for human eyes is about 250:1. 6, brightness value The maximum brightness of the liquid crystal display is usually determined by a cold cathode ray tube (backlight), and the brightness value is generally between 200 and 250 cd/m2. The brightness of the liquid crystal display is slightly lower and the screen will feel dark. Although technically higher brightness can be achieved, this does not mean that the higher the brightness value, the better, because too high brightness of the display may cause the viewer's eyes to be injured. 7, response time The response time refers to the speed at which each pixel of the liquid crystal display reacts to the input signal. Of course, the smaller the value, the better. If the response time is too long, it may cause the liquid crystal display to have the feeling of tail dragging when displaying a dynamic image. The response time of a typical liquid crystal display is between 20-30ms.

Compared to LCD displays and LED displays, LEDs have more advantages in terms of brightness, power consumption, viewing angle, and refresh rate, and have canceled navigation to this page. With LED technology, displays that are thinner, brighter, and clearer than LCDs can be produced. 1, LED and LCD power consumption ratio is about 1:10, LED is more energy-efficient. 2, LED has a higher refresh rate, in the video has a better performance. 3, LED provides a wide viewing angle of 160 °, you can display a variety of text, numbers, color images and animation information, you can play TV, video, VCD, DVD and other color video signals. 4. The response speed of individual elements of LED display screen is 1000 times that of LCD LCD screens. It can also be viewed under strong light and it can adapt to the low temperature of minus 40 degrees. Simply put, LCD and LED are two different display technologies. LCD is a display screen composed of liquid crystal, and LED is a display screen composed of light-emitting diodes. Dear friends, now we should understand the difference between LCD and LED! Then we will certainly say that LED is so good, then I must buy LED display! However, the focus of this article will come: Currently on the market said the LED display The screen is not a true LED display. It is exactly a LED-backlit LCD. The LCD panel is still a traditional LCD display. In a sense, this is a lot of fraudulent nature! The reason why the British Advertising Association organized a violation of the country`s advertising law was that its [LEDTV" LCD TVs misled consumers. For liquid crystal displays, the most important key is the type of LCD panel and backlight, and the LCD panel of the display on the market generally uses TFT panels, which is the same. The difference between LED and LCD is only that their backlight types are different: LED Backlights and CCFL backlights (ie, fluorescent lamps) are diodes and cold cathode lamps, respectively. The difference between LED display and LCD display: LED backlight: power saving (30%~50% compared to CCFL power saving), high price, high brightness and saturation. CCFL backlight: Relative to the LED backlight power consumption (or a lot of power than the CRT), cheaper. Picture difference: LED backlight has brighter colors and higher saturation (CCFL and LED's natural light source are not the same). How to distinguish: LED backlight will be particularly emphasized LED TV, did not emphasize CCFL LCD TV There are still real LED TVs in the market (not backlit, they will be active), SONY and Samgsung have, but the panel is currently under 11 inches, and the price is very expensive, such as SONY 11-inch AMOLED TV asking price about rmB18000, It belongs to the high-end market, so it is rarely available in the market. Let's look at the actual picture comparison between LCD and LED. The following two notebook displays: CCFL backlight LCD on the left and LED backlight LCD on the right, red, green, and blue. The comparison is as follows: As can be seen from the figure, the color difference between the LCD screen and the LED screen is generally not very large under the naked eye. If you just pay for the name of LED, it is not worth the money. It is really not necessary. Smart TV/box information can focus on smart TV information network sofa butle, China's influential TV box and smart TV website, providing information, communication, TV boxes, smart TVs, smart TV software, etc. Answering questions.

The performance of automotive radiators is a major factor affecting the cooling water temperature of automotive engines. There are two main types of materials used in automotive radiators: aluminum and copper. The former is used for general passenger cars and the latter is used for large commercial vehicles. At present, the development direction of automotive technology is light, efficient, and economic. The automotive radiator materials and manufacturing processes are constantly adapting to new requirements. Under the premise of ensuring sufficient heat dissipation capacity and strength, the size, weight, and heat dissipation efficiency are reduced. Higher has become the trend of radiator development. This article studies and tests the problem of high water temperature of the 6DL engine, and compares and analyzes the wind tunnel test results of the copper and aluminum radiators to determine the technical improvement measures and solutions, which can solve the problem of high cooling water temperature of the 6DL engine. Significance. Investigation and analysis of the problem of high water temperature in the 6DL engine We learned from the follow-up investigations of the after-sales service department and users in Henan, Hebei, Shaanxi, etc. that the high horsepower temperature of the high-powered vehicles in the plant experienced high temperatures in summer. . Through investigation and analysis, find out the reason why the water temperature is high: Check whether the fins of the water tank heat dissipation core and the fins of the intercooler heat dissipation core are not properly ventilated by the fan due to clogging. After asking the customer to thoroughly clean the water tank from the inside out with a high-pressure water gun, it was reinstalled on the vehicle and the tracking test revealed that the water temperature was still relatively high. Excluding the fins of the radiator core and the fins of the intercooler heat sink core, the poor heat dissipation caused by the clogging of the ware. Check the problem The engine fan is not damaged, so it is also possible to rule out the poor fan blowing capacity due to engine fan breakage. ) Check the internal cause of the engine: After querying the technical personnel of the Xichai R&D department, when the engine water temperature is lower than 76°C, the engine is in a small circulation state. When the water temperature reaches 76°C, the thermostat will be automatically turned on and the water temperature reaches 86°C. The thermostat is fully open. A thorough inspection and commissioning of the engine of a vehicle with high water temperature revealed that the engine's large and small circulatory systems were working properly.

The automobile radiator is a heat exchange device for heat exchange between the engine coolant and the air of the automobile. The radiator exchanges heat with convection of the air to dissipate the heat of the engine coolant to cool the engine. In an oscillating flow heat pipe automobile radiator, heat is radiated by a forced convection heat exchange between the heat radiating section of the oscillating flow heat pipe and the air. In order to enhance the heat transfer performance between the oscillating flow heat pipe and the air, the heat pipe can be used to effectively increase the heat exchange area and increase the turbulence, thereby enhancing the heat transfer effect. Oscillating flow heat pipe automotive radiator structure diagram, its dimensions and experimental use of the belt-belt copper radiator is the same, so that it is easy to conduct comparative analysis. In the experimental process, the tube-belt copper radiator and the oscillating-flow heat pipe radiator were respectively tested. During the experiment, the heat sink was placed in the mid section of the air duct, different wind speeds were achieved through the air duct, and the situation that the radiator of the automobile was heat exchanged with the air was simulated. The hot end used hot water as the heating medium. In the experiment, air side pressure, temperature, and speed were measured. The experimental study of the heat transfer performance of an oscillating flow heat pipe automobile radiator was shown in the layout of measuring points at the A and B sections, and the nine points uniformly arranged in the air cylinder were measured. Take the average value as the final measurement result; oscillating flow heat pipe radiator water side pressure, temperature and flow measurement point arrangement; pipe belt type copper automobile radiator measuring point arrangement. Test equipment used in the experiment. The solid line is a tube-belt type copper automobile radiator, and the dotted line is an oscillating flow heat pipe automobile radiator. It can be seen from the figure that the heat dissipation of both radiators increases with the increase of wind speed. Obviously this is because the greater the wind speed, the greater the forced convection heat transfer coefficient of the surface, and thus the other conditions are the same. The greater the heat exchange. It can also be seen that at the same wind speed, the greater the water flow, the greater the heat dissipation. And the heat dissipation of the oscillating flow heat pipe car radiator is larger than that of the tube-belt copper car radiator under the same experimental conditions, and the increase rate is up to 26.5%.

Huangshan Kaichi Technology Co.,Ltd is found today 21st December 2021.The main business lines are the Auto Radiator,LCD/LCM,and ODM Crafts.Hope to have a great cooperation with you.