LCD screen how it works

In recent years, most buyers of computer monitors and a large television screens buyers choose LCD screen. Apart from the data size and screen resolution, it is important to know what type of panel (panel Hebrew) of the screen that you are purchasing. The panel is actually the heart of the screen, is the most significant factor for picture quality and affects the basic data such as contrast, viewing angles, and more. Your needs, should determine the type of panel you wish to purchase, the panel will illuminate to your eyes for many hours of watching. On the back side of the screen, the power supply is in charge of the power supply, the current alignment and filter unwanted interference from the power supply. Side, is the video processing unit, its function is to receive the video signal came from your PC or other source and make it different image processing; In case the signal came analog VGA connector, it will be converted to a digital signal before then processed. Go through the closed panel unit. If we open it, we find the following parts: Backlight: On the back wall of the screen panel lighting units are, in most fluorescent lamps screens are long and thin. Lately, began to enter also agree that include expensive LED bulbs - the whole area of ​​the screen. These can be found, for example, laptops like the Dell XPS or the Apple iPhone. The light from these lamps we wish to spread evenly - so the lighting intensity will be the same in all parts of the picture. To do this, use a diffuser light (Diffuser) which receives the light of its lights various spreads it evenly and passes it forward to the user. Then, the light passes through several filters and polarizers, which filters unwanted light waves and polarizers the light that reach a uniform direction to the panel. The panel itself is made ​​of liquid crystals, the video image processing has appropriate, translated into a series of streams which are transmitted through the crystal panel. Features crystals allow them to change their molecules angle depending stream passes. Crystal angle determines how much light passes through it, the screen lit various parts differently. Each pixel consists of 3 sub-pixels of red, green and blue, together they form the range of visible colors. Three families of LCD panels Many are unaware that there are different types of panels, they differ from the properties of the crystals that make them. There are three families that have different panels quality picture performance. 1. TN panel Pros: fast response time, cheap, low energy consumption. Cons: depth of a six-bit color only, contrast and viewing angles are inferior. Uses: Average Internet browsing, office work (documents), laptops (due to low cost and low power consumption). In fact, a screen with TN panel suitable for anyone looking for an LCD screen for use "rules" (non-professional) relatively cheaply. 2. VA panel Advantages: eight-bit color depth, high contrast ratio, improved viewing angles with respect to the Panel TN. Cons: less wide viewing angle IPS panels, high energy consumption in relation to a panel, TN, a higher price. Uses: good image quality in general use (web and documents), the possibility to work graphically, improved picture quality for TV monitors. 3. IPS panel Pros: Best viewing angles compared to other two types, high quality color (eight-bit), good contrast (though not at the level of VA panels). Disadvantages: higher power consumption compared with other types of panels, requires strong backlighting. Applications: professional graphics work, very good image quality for general use (and prolonged computer work), improved picture quality for TV monitors. What are the differences between the panels? Features various panels families crystals are those that determine image quality basic parameters, such as those of the screens features derived directly the quality of the panel: Viewing angles When'll draw to the right-left or up and down, the screen has a narrow viewing angle, the image shuts down or you'll get whiter will obscure the picture, also the color will lose their original hue. Color depth TN panels present a picture quality six-bit color channel, which leads to only display 262,000 colors. Using artificial methods (interpolation) manufacturers fail to show 16.2 million colors or more, but the quality is not equal to the more expensive panels. VA and IPS panels quality image display eight-bit color, so the screen will show the true colors 16.7 million. Contrast (static) Represents the greatest proportion (to make it to the panel) between the darkest bright spot in the picture. High-contrast panel, displays an image with greater depth. Contrast (Dynamic) To increase the contrast ratio, the manufacturers use different methods: the radicalization of the black and white image with the video processor (which can damage the presentation details the dark parts of the picture) or amplification of weak intensity of the backlight. A weakness of LCD screens is the fact that the lighting is on their back without a break (as opposed to plasma or CRT screens), it is very difficult to block it entirely, what hurts the depth of black color and makes it in many cases to gray. Therefore, when viewing dark scenes that are problematic for the screen, the backlight is darkened and prevents leakage of light in the image. Darkening or increasing the lighting is not immediate and therefore often can be detected light intensity change. Response Time Represents the length of time that the individual pixel goes from white to black and vice versa, is measured in milliseconds. Due to the fact that a single standard manufacturers are committed to, choose any of them to display measurement data were conducted using different methods, some manufacturers measure gray to gray response time (which displays results faster, apparently). In the past, TN screens displayed the shortest response times, but now, with the help of various techniques, most types of panels show good results, in reality, most of the new screens do not suffer from the problem of spreading visible. So how to recognize the type of the panel? Dissolution of the panel screen, reveals a sticker on the back. This example shows that the panel is made in a factory joint panels of LG and Philips. A Google search of the model code LM170E01 panel shows that this is a 17-inch TN type a response speed of 16 ms. The panel type is not specified on the data it provides the manufacturer, or even a particular model will be sold as it comes with different types of panels of course, we can not begin to dismantle agree stores as customers. But there are a few tips to identify the panel: Price: Most LCD monitors come with a cheap TN panel type. Glimpse data sheet: 16.2 million figure indicates colors TN panel (although some manufacturers have begun to note given 16.7 million, mainly marketing reasons). Research: information on the exact model forums and product reviews sites. Database: Use FlatPanels huge database includes panels on many models. All in accordance with the needs Knowing the needs they serve as the LCD screen you wish to buy it, be it a computer or television screen. If you would like to purchase a screen that provides an impressive ratio of the size of the price, only for general uses, you will be satisfied with TN panel LCD panel: For example, the total price TN 22 inch is typically cheaper compared to a smaller screen, for example, 20 inches, but with a high quality panel compared. But, if you want to purchase a screen for professional use (such as graphics) or for prolonged work at a computer, you may want to spend more and get a quality panel that will provide you with hours of fun from the screen.