Summary

The operation of an LCD, or “Liquid Crystal Display”, television set is dependant upon the behaviour of molecules of liquid crystal, held between two polarised screens. As a voltage is applied, or removed, the liquid crystal molecules align themselves one way, or the other, allowing light to pass, or not, and hence creating light, or dark, spots in a displayed image. Colour is applied, to each picture element, or “pixel”, by individual red, green and blue colour filters.

LCD Television Features

The aspect ratio of a television screen or, more properly, of a displayed image, is the ratio of its width to its height. DVD movies, or HD (“High Definition”) television broadcasts, for example, have a typical aspect ratio of 16:9 ­ that is, the image displayed almost twice as wide as it is high ­ but the aspect ratio that you choose will depend largely on the type of viewing that you are intending to do. Conventional television pictures have an aspect ratio of 1.33:1, more commonly quoted as 4:3, and you will see so-called “letterbox”, or black bar effects, if you view 16:9 material on a 4:3 television set, or vice versa.

The screen size of an LCD television set is obviously an important factor, and it should be borne in mind that, to date, screen sizes have been somewhat smaller than those of competing, Plasma television sets. The principal problem is that larger screens require more individual picture elements, or pixels, which, in turn, require more transistors, and production quality has been difficult to maintain in screens above 40 inches, or so. In terms of depth, however, LCD ­ and Plasma, for that matter ­ television sets score highly over conventional “tube” televisions, with many being as little as 3 inches deep, and light enough to hang on a wall, or mount of a ceiling.

Another desirable characteristic of an LCD television screen is something known as “active matrix” (as opposed to the less expensive “passive matrix”). Active matrix allows pixels to be switched on, or off, more rapidly than the passive alternative, allowing a faster refresh rate, and an absence of “ghosting”, or blurring.

Conclusion

A state of the art LCD television set is all very well, but it does need to be installed correctly, and safely, and viewed at the correct distance, to be experienced to its full capability. As a rule of thumb, you should be able to sit comfortably at a distance of three times the diagonal screen measurement, from the screen, for optimum viewing. Any closer than this, and individual pixels are likely to become visible, spoiling the effect. You may also need to consider the viewing angle ­ the higher the better, up to as high as 175 degrees in some cases ­ when positioning your LCD television.

In terms of actual, physical installation, many articulated, tilting or swivel mounts are available for walls, and, indeed, ceilings, although do take care to ensure that these are properly fitted ­ perhaps professionally ­ to protect what is likely to represent a fairly sizeable investment. Another popular option, for slightly smaller LCD televisions, is a free standing, or table mount, often equipped with a column, in which mains, and other, cables can be concealed.