second way is the way of character box-A (Letterbox-A), 16: 9 images maintain its distortion, but up and down the screen leaving a black bar; The third way is-B (Letterbox-B) The way the first two compromise on both sides of the horizontal direction beyond the screen part, vertical up and down the black bars narrower than the second, the image aspect ratio of 14: 9. The current consumer notebook in order to meet the needs of home entertainment, usually the screen aspect ratio of 16:9 or 16:10. Widescreen can bring greater display area at the same time, does not significantly increase the area of the body and screen, and thus reduce the overall weight, another the same length of the diagonal widescreen, the area than the normal 4:3 smaller, can reduce production costs, due to the tube long and relatively smaller size of the screen, wide-screen brightness and contrast in the average ordinary 4:3 normal screen winning. The ================================ split line ================ ======= dividing line ===================== LCD monitor: screen size and screen size is the length of the diagonal LCD display screen, the unit is inches. CRT monitors, yes, the nominal liquid crystal display screen size is the size of the actual screen display, 17-inch LCD display viewing area close to the 19-inch CRT flat screen monitors. Mainstream product screen size of 17 inches and 19 inches. For more and more widescreen LCD monitor, the screen size is still the length of the diagonal LCD screen, the current commercially available products to 19 inches mainly. Screen ratio widescreen LCD monitor is no uniform standard of 16:9 and 16:10. Widescreen LCD monitor with more effective viewing area and other advantages compared to conventional LCD may become the development direction of the liquid crystal display may become the mainstream in the future. It is noteworthy that, in the same screen size, either 16:9 or 16:10 widescreen LCD monitor, the actual screen area actually smaller than the normal 4:3 LCD monitor. The ======================= split line ========================= the ======== split line ======================================== LCD monitors: the best resolution LCD monitor has the best resolution of 17-inch and 19-inch 1280 × 1024 19 widescreen 1440 × 900 20-inch 1920 × 1050 15 widescreen 1280 × 800 15 S & P The screen is 1024 × 768 ======================== dividing lines ================== the ================ split line ================================ ===== LCD: LCD panel LCD panel liquid crystal display has a very close relationship, the LCD panel production, the pros and cons, and other factors are linked to the liquid crystal display quality, price and market trends. Which the LCD panel related to the response time, color, viewing angle, contrast, and other parameters most important players. From the LCD panel can be seen that the performance of this LCD display quality? Kobayashi on the Internet to find information look at the LCD panel, as long as it is for the current mainstream LCD panel, so that everyone in mind one end of the purchase of liquid crystal display. VA type: VA type liquid crystal panel is widely used in the current display products for use in high-end products, 16.7M colors (8bit panel) and large viewing angle is the most obvious technical characteristics of the VA type panel points into two: MVA, PVA. The MVA Type: full name (Multi-domain Vertical Alignment) is a multi-quadrant vertical alignment technology. It is the use of the protrusion so that the LCD at rest is not a traditional upright, but a biased point of stationary; voltage so that the liquid crystal molecules into level through the backlighting is more rapid, so that we can significantly reduce the time because of changes to the liquid crystal molecules, so that the viewing angle is wider. Up to 160 degrees or more, in the perspective of the increase in reaction time is shortened to less than 20ms. PVA type: Samsung introduced a panel type is a vertical image adjustment technology that directly change the liquid crystal cell structure, so that the display performance dramatically superior to MVA light output and contrast can be obtained. In addition, these two types based on extension of the improved two kinds of S-PVA and P-MVA panel type, more up on technology development, viewing angle of up to 170 degrees, the response time was controlled in less than 20 milliseconds (using Overdrive to accelerate up to 8ms the GTG), contrast ratio can easily exceed the high standards of 700:1, the majority of Samsung's own brand of PVA LCD panel. IPS-type: the IPS type LCD panel has a large viewing angle and delicate color, etc., seem relatively transparent, and this is to identify a method of the IPS type LCD panel, the PHILIPS many LCD monitors are IPS type panel. S-IPS compared with second-generation IPS technology, it also introduces a new technology to improve the gray-scale reversal of the IPS mode in certain perspectives. LG and Philips independent panel manufacturers is the IPS for the technical characteristics of the launch of the LCD panel. TN Type: This type of LCD panel used in entry-level and midrange products, affordable, inexpensive, many manufacturers use. Technically, compared with the first two types of LCD panel slightly less on the technical performance, it could not be demonstrated 16.7M bright color, only up to 16.7M colors (6bit panel) but the response time is easy to raise. The viewing angle is also subject to certain restrictions on the viewing angle is not more than 160 degrees. The market is generally less than 8ms response time products mostly used in the TN LCD panel. The =================== split line ============================= ====== dividing lines ========================================= LCD types and the advantages and disadvantages of the display backlight (LCD CCFL, LED) LCD backlight display, the biggest difference between the principle of liquid crystal is different from the plasma is the liquid crystal must rely on passive light source, while plasma TVs are self-luminous display device. LCD backlight technology of the mainstream market, including the two types of LED (light emitting diode) and CCFL (cold cathode fluorescent lamp). The cold cathode fluorescent lamps (Cold Cathode Fluorescent Lamp; the CCFL) traditional LCD displays are based CCFL (cold cathode fluorescent tube) backlight. CCFL backlight design: the side-in "and" straight sets "type, but the side-in a higher rate of optical impairment due to the light guide design, thereby allowing the limited brightness of the backlight brightness when the panel size increases on the lower, only 8 inches to 15 inches TFT LCD panel is Laptop, Desktop personal viewing purposes, but at home to watch the LCD TV size above the side-brightness will be difficult to meet, replaced by The Telok type. However, the greater the size of the LCD backlight proportion of share of the cost, the higher is referring to is the Telok CCFL backlight according to statistics, the same to Telok type CCFL backlight, 15 inch backlight only 23% of the overall cost, but by 30 inches to 37 percent, and estimated to 57 inches the backlight share of the cost will be 50%. So, in straight sets CCFL backlight is only suitable for use at about 30 inches medium-size LCD TV is not suitable for use in the design of the larger area. CCFL is the use of mercury gas discharge lighting, although made by the EU RoHS Directive, as long as the "dose" mercury can still accept the standard the following , but no one can guarantee future standards to zero content (no allowed to use), then the CCFL will not be used or will be diverted to non-mercury type CCFL. Even non-mercury type CCFL is technically feasible, but the CCFL is still a closed optical tube of the gas discharge electronic lighting, fluorescent tubes, the external force of the anti-subject is limited, the larger the collision will light pipe rupture, so that the lighting failure, the relative other solid electronic lighting (LED) does not have this concern. In addition, in straight sets do not need the light guide plates, than matt impairment, so I do not need the brightness enhancement film, brightness enhancement film is a small number of industry patent technical , expensive, Telok eliminates the need for light guide plate and a brightness enhancement film, this helps to reduce costs. However, the the Telok type CCFL has its shortcomings, in order to enhance the brightness on the screen, you must increase the number of fluorescent tubes, and then fluorescent tubes, close-packed set of results will be not conducive to heat, since the distance of about white space reduction, had from the thickness level to increase the heat space, however, the thickness increases the advantages of LCD TV is also equal to partially offset loss: thin. Incidentally, in big inch LCD TV with CCFL light tube, light pipe length must also increase and growth should inch, however, the longer CCFL fluorescent tubes, fluorescent tubes of the middle and both ends prone to the question of the brightness MURA and color MURA , thereby affecting the backlight light are light are, you must spend the proliferation of film to strengthen the light all but the proliferation of film will also have a light transmittance of the impairment in order to continue to maintain , reduce the brightness, the brightness to reduce the results had to increase the fluorescent tubes, the number of reinforcement, but As mentioned above: increase in fluorescent tubes, the heat will be more difficult to design, to increase the thickness of the backlight module, and even electricity increase, is understood that the CCFL backlight electricity accounted for 90% of the overall electricity consumption in LCD TV high. Therefore, the change of backlight technology is one of a direction to change the LCD picture quality. Light emitting diode (Light Emitting Diode; the LED) CCFL backlight has many side effects concerns, the industry also seek new backlight technology, LED is one of the possible options, such as Sony Qualia series of television, that is, high side of the large size (40 inches, 46 inches) LCD TV, the backlight part is posed by the use WLED, known as the WLED backlight technology. LCD Monitor LED backlight technology R & D is also to the substantive stage in the 2007 CES Conference and Expo, we can see related products. LED backlight a number of benefits, the first solid electronic lighting, anti-collision by higher than the CCFL, and no environmental regulations concerns of mercury gas, there is no leakage of UV rays concerns, color saturation and life beyond The CCFL Another LED forward voltage to drive, unlike CCFL need to communicate positive and negative voltage, even if only on the positive drive voltage, LED level of demand is also lower than the CCFL. Furthermore, the LED brightness only with pulse width modulation (Pulse Width Modulation; PWM) mode can be adjusted, and available in the same way to suppress the blur on the TFT LCD display, however, the CCFL dimming on more complex and can not suppress the blur to separate suppression. The LED backlight has many advantages, but also has its drawbacks, the first luminous efficiency, the same electricity, the LED does not and the CCFL, the heat dissipation problem than CCFL serious, in addition to the LED is a point light source, linear with CCFL LED light source compared to the real difficult to control light are, in order to reach as much as possible light, produced by the LED on the characteristics of fine pick to select a large number of features (wavelength, brightness) for the same a backlight in this selection cost is quite high. Fortunately, the LED luminous efficiency is also the ascension, is now available to more than 100 ml / W, so better color saturation, and the backlight WLED row set a more relaxed, thereby allowing the electricity and heat problem soothing, and manufacturing yield continuous improvement maturity, selected features consistent bright LED costs will be reduced. Simply change the backlight technology may be enough to trigger the LCD revolution, then we went to look at other LCD technologies. OLED (Organic Light Emitting Diode) or organic light emitting diode. OLED display technology with traditional LCD display, no backlight, the use of very thin coating of organic material and the glass substrate, these machines material emits light when there is a current . OLED display screen can be done lighter and thinner, larger viewing angle, and can significantly save power. However, it life and the price is to limit the bottleneck of the development of the LCD . OLED panel applications is a subject of attention, and an earlier panel of the small size of process. View to the customer's plan , from 2008 to 2009 there will be more models come out, but still sub-panel-based, and even aircraft and shipments compared with a significant increase in market share will not more than 10%. OLED original of this because of their own thin, contrast, viewing angle, power and other conditions in different areas than those of TFT-LCD to be outstanding, has been subject to the attention of the industry that will replace the TFT-LCD, a few years ago also have invested in research and development. Encounter a problem, however, aspects of OLED technology itself, the life problems to be overcome; the other hand, the TFT-LCD technology continues to sophisticated, and can also provide excellent contrast and viewing angle, resulting in OLED demand still can not lift upgrade, and the market oversupply of limited price competition; original investment in the industry could not escape the fate of dissolved and downsizing. Taiwan's Wintek has invested to set up a victory garden into OLED research and development, seeing OLED and TFT-LCD can not compete, in particular, the cost difference, specifications TFT-LCD can easily reach the 170-degree viewing angle, 500:1 contrast, brightness increase, you can also do the thin reaction speed than less, but to reach the human eye can be of acceptable range. Victory garden has also been removed before, leaving only several R & D personnel to do the development of materials back to win China. OLED life span and price if substantial improvement, there are still opportunities; is limited at this stage with particularity, stressed that the products you want to create something new; large amount of time yet to see. AMOLED (Active Matrix / the Organic Light Emitting Diode) active matrix organic light-emitting diode panel (AMOLED) is called next-generation display technology, including Samsung Electronics, Samsung SDI, LG Philips attaches great importance to this new display technology . Apart from Samsung Electronics and LG Philips to develop large-size AMOLED products as the main direction, Samsung SDI, AUO is to small and medium size development direction. Product performance from the finished product, if the the AMOLED cost can effective control, then the traditional LCD panel technology will be a great challenge. AMOLED One of the advantages: no backlight AMOLED One of the advantages of: color saturation larger AMOLED One of the advantages: You can reach 180 degree viewing angle AMOLED One of the advantages of the IPS or VA panel : an effective solution to the LCD panel, dynamic fuzzy problems in the above the four OLED virtues, we are particularly concerned about the fourth characteristics, because in the current market of desktop LCD monitors, LCD screen can not be solved dynamic fuzzy problems. The dynamic screen of the LCD screen is fuzzy, usually refers to screen transformation process, the occurrence of the blurred edge profile, the dynamic picture blurring occurs for two reasons, a liquid crystal response time, and phosphor residual light the other is the TFT drive, like the Hold mode image control. Hold the main cause of the so-called fuzzy dynamic picture "Hold mode" display a Frame image is displayed in a certain period of time in the TV screen, Hold the equivalent of a vertical cycle (16.7 milliseconds) general words, we are quite clear, liquid crystal response time for dynamic screen display is very important, because the LCD TV, a picture of the conversion time is about 16.7 ms, so the response time of LCD TV can not be compared to 16.7ms shorter, for dynamic screen picture performance is very important. However, there is a case even if the LCD's response time of 0ms (which is unlikely and difficult), fuzzy , or will not disappear. This is because the LCD screen is the use of "Hold mode" method to display the image. According to some experimental reports, we can use the "Hold" approach displayed on the screen moving painting, will be rocking on the retina. Shaking accumulated over time, dynamic picture is blurred. And to improve the response time of LCD display methods must be developed to shorten the time of "Hold". According to the above situation, the dynamic picture of the LCD screen is fuzzy, the determination can not be used in a long time, from white to black and black to white, change the time of the LCD response time to represent. Improve the dynamic picture blur caused by Hold time if the response time of the is 0ms ideal LCD panel (Hold 100%) of the case, MPRT is 16.7 ms (frequency 60 Hz). Hold 50% , the MPRT approximately 8.3ms; the Hold time was 25% the MPRT for 4.2ms. General LCD the MPRT in the 8ms following; commercial products LCD high quality requirements , its MPRT can speculate on the following 4ms. Previously described the MPRT containing liquid crystal response time and Hold time two elements, therefore, if you want the image display quality, liquid crystal response time of hope than the above value is smaller. Improving LCD response time, high-speed dynamic model of OCB, IPS, VA, Over-drive drive. Now, the emphasis on painting quality of LCD TV has these methods into production. Cause dynamic picture blurred, there are two ways to improve due to the Hold time. With the screen frequency to a point off the backlight source, the other is to speed the use of motion compensation technology. The first use of the backlight flashes and black signal insertion. In these two technologies, the most interesting dynamic compensation technology. Point backlight off and the black signal insertion intermittent display method to improve the dynamic picture fuzzy, and relatively simple to achieve. However, in the case of a large screen, high brightness, easy to produce the flickering of the screen. In contrast , under dynamic compensation speed without increasing the screen flashing under the premise, the method can improve the dynamic picture fuzzy, but because of the need for large-scale signal processing circuit, until now still not easy to achieve. Japanese manufacturers published use to shorten the Hold time to improve quality in the past two years, quite a lot of companies use to shorten the Hold time to improve the quality of related technologies and products. For example, the Japanese industry to the use of dynamic compensation for high-speed display technology to produce 32-inch WXGA LCD TV. Method is the use of motion compensation technology, the screen frequency of the picture signal and drive, from the usual 60Hz to 90Hz, the Hold time is shortened to about 70%, and use the scanning backlight off reduced to 70%, a total of shortening by 50%. Without increasing the screen flashing under the premise of improved dynamic picture fuzzy. 90Hz under the backlight off point, the human eye is not easy to feel the flickering. In addition, there are other industry movement motion compensation technology to increase the number of the frame rate to 120Hz to improve the dynamic quality. Mainstream LCD backlight uses a short service life of the CCFL (cold cathode fluorescent lamp), which is the LCD Mishap. Fortunately, people now find it's successor - the LED. Defects of the traditional CCFL backlight in-depth understanding of the LED backlight technology, we need to first understand the current backlight technology exists. We know that the LCD is a material between the liquid and crystal. LCD wonderful is the current to change its molecular arrangement of the state applied to the LCD voltage can control the light throughput, which display a wide variety of images. But the LCD does not light, all LCD backlighting . LCD backlight almost all of the CCFL (Cold Cathode Fluorescent Lamps, Cold Cathode Fluorescent Lamp). Due to the cold cathode fluorescent lamp is not a flat light source, so in order to achieve uniform light output of the backlight, the LCD backlight also with the diffusion plate, light guide plates, sounding board, and many other auxiliary devices. Even so, it is still very difficult to obtain uniform light output such as a CRT. Most LCD all white or all black screen is displayed, the screen edge and center differences in brightness are very obvious. Addition to the structural complexity and light output uniformity, and CCFL LCD backlight headache - a short service life. CCFL backlight, the vast majority of 2 to 3 years after the brightness decreased very significantly (life of 15,000 hours to 25,000 hours), many LCD (especially the notebook computer's LCD screen) will be used for several years, the screen turn yellow. dark hair phenomenon, which is the CCFL attenuation of shorter defects caused. At the same time, CCFL backlight must contain a diffusion plate, and reflector optics, the volume of the LCD can not be further narrowed. Power consumption, with CCFL backlight LCD is also not satisfactory, the 14-inch LCD CCFL backlight often need to consume 20W or even more power. Notebook computers and portable devices, their life will undergo a major test of In order to solve the CCFL of these flawed, almost all LCD manufacturers began looking for more excellent LCD backlight. LED ultra-low power consumption, extremely long working life and a simple structure, quick access to the LCD manufacturers of all ages, then the LED is what it is? it magic? In fact, LEDs (Light Emitting Diode, Light Emitting Diode) is not cutting-edge products, it can be seen everywhere in our daily lives: roadside billboards, colorful, different colors of light on household appliances, mobile phones backlight button The car headlights, etc., using LED as light source. LED in the 1960s after the birth was identified as the terminator of the fluorescent tubes, light bulbs and other lighting equipment, and some even think the LED will be created in a new era of lighting, culminating in all occasions the need for lighting . LED works is completely different and our common incandescent, fluorescent, LED essence, is a semiconductor device. The core part of the LED is composed of P-type semiconductor and N-type semiconductor chip, there will be a special conductive properties of the thin layer at the interface of the P-type semiconductor and N-type semiconductor, is often said that the PN junction (PN Junction transistors). PN junction can produce resistance to diffusion of majority carriers in the P-type semiconductor and N-type semiconductor PN junction forward voltage is applied, the current from the LED anode to Yin pole, while the minority carrier in the PN junction compound, with the majority carrier excess energy will be transformed into light and released. LED It is based on this principle of electro-optical conversion. Depending on the physical properties of semiconductor materials , the LED may be issued from the ultraviolet to the infrared different band, different colors of light. The =================== split line ============================= the ======== split line ======================================== LCD display: Bandwidth Bandwidth is a very important parameter of the display was able to determine the performance quality of the display. The so-called bandwidth is referred to the monitor video amplifier pass band width, the bandwidth of a circuit is actually a reflection of the response speed of the circuit on the input signal. More bandwidth, the smaller the inertia, the faster the response, allows the signal the higher the frequency, the smaller the signal distortion, it reflects the resolving power of the monitor. The higher the number the better. Bandwidth on behalf of the display capabilities of a composite indicator, refers to the per second scan the pixel number, that is the sum of the display of frequency points for each scan line in a unit time, in MHz. The larger the bandwidth show that the ability to control, the stronger the better display. Bandwidth is calculated as follows: in theory, the bandwidth B = r (x) × r (y), x V r (x) that each horizontal scan line of pixels the number of r (y), said each frame, the horizontal scan B said bandwidth of the lines V said that the screen refresh rate per second (ie, field frequency)
