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The LCDs used for projection systems are most often small reflective or transmissive panels lit up by a bright arc lamp source. A number of lenses magnifies the reflected or transmitted image and then sends it on a screen. In front-projection systems the LCD is located on the same side of the screen as the viewer, however in rear-projection systems the screen is lit up from behind. Projectors of more expense and performance sometimes utilise three separated LCD panels, creating separate red, green, and blue images that come together to make a coloured picture on the screen.

The increasing demand for pictographic displays has placed a growth in emphasis on the switching speed of liquid crystals. This has demanded the development of devices build with smectic liquid crystals, certain kinds of which have a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this point the most developed smectic device. In it the liquid crystal molecules are managed in layers perpendicular to the substrate planes, which are distanced by one or two micrometres, and in the layers the molecules are on a slant, as demonstrated in the figure. The host liquid crystal holds optically active molecules, and a slight result of the optical activity and the shape of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, likeable to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and within the plane of the layers. Thus, there must be a permanent charge separation across the liquid crystal layer in the SSFLC, and its sign is directly paired to the tilt direction of the molecules. An applied voltage of the right sign can reverse the direction of this dipole in tens of microseconds and in so doing reverse the tilt direction of the molecules. The resultant change in optical properties can cause a change from light to dark if or when one or more polarizers are used.

SSFLC devices have been marketed for big passive-matrix presentations, but their high cost and complexity has prevented them from having any significant impact on the market. Small transmissive and reflective active-matrix SSFLC displays, however, show some probability for use as aspects in projection systems or as viewfinders in digital cameras. Their immediate reaction allows them to be utilised in time-sequential colour systems, in which high cost colour filters are replaced by a coloured backlight that flashes red, green, and blue in quick succession (about 100 cycles in a second). For example, the liquid crystal can be switched to a transmissive state during the red and green periods but then to a nontransmissive state during the blue period, displaying the result that the eye sees an average of red and green light, or the colour yellow.

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