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The LCDs utilised for projection systems are most often small reflective or transmissive panels set off by a powerful arc lamp source. A series of lenses enlarges the reflected or transmitted image and then displays it on the screen. With front-projection systems the LCD is located on the same area of the screen as the viewer, although in rear-projection systems the screen is set off from behind. Projectors of greater cost and performance sometimes be found with three discrete LCD panels, casting separate red, green, and blue images that blend to form a coloured display on the screen.

The growth in demand for video presentations has granted a particular emphasis on the switching speed of liquid crystals. This has necessitated the development of devices employing smectic liquid crystals, certain types of which possess a speedier electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this time the most progressive smectic device. Within it the liquid crystal molecules are managed in perpendicular layers to the substrate planes, which are differentiated by one or two micrometres, and in the layers the molecules are slanted, as shown in the figure. The host liquid crystal possesses optically active molecules, and a minor outcome of the optical activity and the shape of the molecules is the appearance of a permanent charge separation, or ferroelectric dipole, analogous to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and throughout the plane of the layers. Hence, there must be a permanent charge separation across the liquid crystal layer in the SSFLC, and its sign is directly partnered to the tilt direction of the molecules. An applied voltage of the corresponding sign can reverse the direction of this dipole in tens of microseconds and by doing so reverse the tilt direction of the molecules. The corresponding change in optical properties can cause a change from light to dark in the case that one or more polarizers are utilised.

SSFLC devices have been marketed for big passive-matrix presentations, but their high cost and intricacy has impeded them from enjoying any great progress on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have some promise for use as aspects in projection systems or as viewfinders in digital cameras. Their speedy reaction allows them to be used in time-sequential colour systems, in which expensive colour filters are emulated by a coloured backlight that flashes red, green, and blue in quick pace (about 100 cycles a second). For example, the liquid crystal could be switched to a transmissive state between the red and green periods then to a nontransmissive state during the blue period, creating the end result that the eye sees an average of red and green light, or the colour yellow.

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