| By :
Andy Grant
The term "LCD" is one that most of us seem to take for granted. But what does LCD mean and why is it important? This article provides a simple explanation of LCD technology. LCD stands for "liquid crystal display." Essentially, this term is used to refer to a device that contains two transparent polarized panels, with a liquid crystal solution located in-between them. Electricity causes light to shine through the panels from behind, and an image appears. More specifically, polarized panels will only pass light waves in one plane, and the panels are positioned at a 90 degree angle to each other, which means light from one plane cannot pass through the other panel because of its angle. But when electricity passes through the liquid crystals, segments are switched on or off, to produce a specific image. The crystals are actually lined up in a particular way that allows the light to twist through both panels, in order to be visible on the other side. When it comes to projectors, LCD projectors typically send light through a prism from a metal halide lamp that separates the light into colors (red, green and blue). In other words, the video signal is essentially split by color, and the prism sorts the colors and projects the specified images. How are the colors sorted? Put simply, three poly silicone panels are present (one for each color) and as the polarized light passes through the panels, individual pixels can be allowed to open up and allow light through, or close up to block the light. Combinations of open/closed pixels produce a virtually limitless range of colors and shades in the viewable image. Of course, all this happens in such rapid succession that you never notice the delay - the images, projected so quickly, seem to "move" on the screen. There are projectors that use other forms of technology (non-LCD) but LCD projectors are the most popular because they are lightweight and extremely portable. Typically, metal halide lamps are used for their ideal color temperature and ability to display a broad spectrum of colors. Additionally, metal halide lamps can produce a vast amount of light in a relatively small area, which makes it ideal for high-lumen outputs. Arguably, CRT (cathode ray tube) technology provides the cleanest, crispest images, but it's lack of portability makes it less convenient than LCD projectors; therefore, most rental projectors are LCD projectors.
|
![[Valid RSS feed]](http://www.articlesbacklink.com/images/icon_Rss.png "XML Feed For RSS"){kind=icon}
Category Rss Feed
Print This Article
Add To Favorites
