LCD Display

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LCD Display

by umaa » Sun Aug 02, 2009 7:23 pm
In the past decade, rapid technological progress and a greater demand for high-quality digital imaging have led to dramatic advances in video display technology. The dominant technology currently used in most consumer product displays is the active matrix liquid crystal diode display(LCD).
LCDs apply thin-film transistors (TFTs) of amorphous or polycrystalline silicon sandwiched between two glass plates. The TFTs supply voltage to liquid-crystal-filled cells, or pixels, between the sheets of glass. When hit with an electric charge, the liquid crystals untwist to an exact degree to filter white light generated by a lamp. This filtered light shines directly on the viewing screen or, in the case of projection televisions, is projected through a small chip that acts as a lens. LCDs that are capable of producing color images, such as in televisions and computers, reproduce colors through a process of subtraction, blocking out particular color wavelengths from the spectrum of white light until only the desired color remains. It is the variation of the intensity of light permitted to pass through the matrix of liquid crystals that enables LCD displays to present images full of gradations of different colors.
The nature and functioning of LCD displays present many advantages relative to other display technologies. The amount of power required to untwist the crystals to display images, even dark ones, is much lower than that required for analogous processes using other technologies, such as plasma. The dense array of crystals displays images from computer or other video graphics sources extremely well, with full color detail, no flicker, and no screen burn-in. Moreover, the number of pixels per square inch on an LCD display is typically higher than that for other display technologies, so LCD monitors are particularly good at displaying large amounts of data with exceptional clarity and precision. As a result, LCD TVs are considered the best display platform for video games, high definition television, movie special effects, and other graphics-intensive uses.

The process through which an LCD monitor displays different colors is most closely analogous to


an hourglass partially blocked such that a limited stream of grains of sand fall into the lower portion


a series of filters that separate all of the components of a mixture according to size

a recording studio soundproofed so that any performances within are muted to those outside

a piece of construction paper with outlines of characters cut out such that a lamp in front of the paper casts shadows in the shapes of the characters

an air vent that emits warmer air outside of a building while an air conditioning system cools the interior of the building

Why Answer choice E is wrong? OA is D
Source: — Reading Comprehension |

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by abhasjha » Mon Aug 03, 2009 11:44 pm
The question seems pretty similar to parallel reasoning question of CR . look at the form .

" blocking out particular color wavelengths from the spectrum of white light until only the desired color remains"

for choice E to hold true - all warm air needs to be blocked till the point cool air starts coming in .

Option E says that - "air conditioning system cools the interior of the building " and this is where the difference lies . A different agent (air conditioner is producing the desired effect of cool air .

and so the option E is wrong .

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Re: LCD Display

by ketkoag » Fri Aug 07, 2009 1:46 am
umaa wrote:In the past decade, rapid technological progress and a greater demand for high-quality digital imaging have led to dramatic advances in video display technology. The dominant technology currently used in most consumer product displays is the active matrix liquid crystal diode display(LCD).
LCDs apply thin-film transistors (TFTs) of amorphous or polycrystalline silicon sandwiched between two glass plates. The TFTs supply voltage to liquid-crystal-filled cells, or pixels, between the sheets of glass. When hit with an electric charge, the liquid crystals untwist to an exact degree to filter white light generated by a lamp. This filtered light shines directly on the viewing screen or, in the case of projection televisions, is projected through a small chip that acts as a lens. LCDs that are capable of producing color images, such as in televisions and computers, reproduce colors through a process of subtraction, blocking out particular color wavelengths from the spectrum of white light until only the desired color remains. It is the variation of the intensity of light permitted to pass through the matrix of liquid crystals that enables LCD displays to present images full of gradations of different colors.
The nature and functioning of LCD displays present many advantages relative to other display technologies. The amount of power required to untwist the crystals to display images, even dark ones, is much lower than that required for analogous processes using other technologies, such as plasma. The dense array of crystals displays images from computer or other video graphics sources extremely well, with full color detail, no flicker, and no screen burn-in. Moreover, the number of pixels per square inch on an LCD display is typically higher than that for other display technologies, so LCD monitors are particularly good at displaying large amounts of data with exceptional clarity and precision. As a result, LCD TVs are considered the best display platform for video games, high definition television, movie special effects, and other graphics-intensive uses.

The process through which an LCD monitor displays different colors is most closely analogous to


an hourglass partially blocked such that a limited stream of grains of sand fall into the lower portion


a series of filters that separate all of the components of a mixture according to size

a recording studio soundproofed so that any performances within are muted to those outside

a piece of construction paper with outlines of characters cut out such that a lamp in front of the paper casts shadows in the shapes of the characters

an air vent that emits warmer air outside of a building while an air conditioning system cools the interior of the building

Why Answer choice E is wrong? OA is D
because D clearly represents a situation where there is a lamp and the light emitted by that lamp is modified to produce different effects or colors.. and this same situation is described in the passage..
hence true..