Philips 150B user manual LCD Panel Technology, Return To Top Of The Page

FAQs (Frequently Asked Questions)

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LCD Panel Technology

Q:What is Liquid Crystal Display?

A:A Liquid Crystal Display (LCD) is an optical device that is commonly used to display ASCII

characters and images on digital items such as watches, calculators, portable game consoles etc. LCD is the technology used for displays in notebook and other small computers. Like light-emitting diode and gas-plasma technologies, LCD allows displays to be much thinner than cathode ray tube (CRT) technology. LCD consumes much less power than LED and gas-display displays because they work on the principle of blocking light rather than emitting it.

Q:How are LCDs made?

A:LCDs are created from two glass plates separated from each other at a distance of a few

microns. Plates are filled with liquid crystal, then seals together. The top plate is colored with a RGB pattern to make the color filter. Then polarizers are glued to both plates. This combination is sometimes called "glass" or "cell." The LCD cell is assembled into a "module" by adding the backlight, driver electronics and frame.

Q:What is polarization ?

A:Polarization is basically directing light to shine in one direction. Light is electromagnetic wave.

Electric and magnetic fields oscillate in a direction perpendicular to the propagation of the light beam. The direction of these fields is called "polarization direction." Normal or non-polarized light has fields in several directions; polarized light has a field in only one direction.

Q:What differentiates passive matrix LCDs from active matrix LCDs?

A:An LCD is made with either a passive matrix or an active matrix display grid. An active matrix has

a transistor located at each pixel intersection, requiring less current to control the luminance of a pixel. For this reason, the current in an active matrix display can be switched on and off more frequently, improving the screen refresh time (your mouse pointer will appear to move more smoothly across the screen, for example). The passive matrix LCD has a grid of conductors with pixels located at each intersection in the grid.

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