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The LCDs built in projection systems are usually small reflective or transmissive panels lit by a bright arc lamp source. A series of lenses enlarges the reflected or transmitted image and sends it on the screen. For front-projection systems the LCD is set on the same side of the screen as the viewer, while in rear-projection systems the screen is lit up from behind. Projectors of greater cost and performance might utilise three separated LCD panels, forming separate red, green, and blue images that blend to make a coloured picture on the screen.

The growth in desire for visual displays has granted a special emphasis on the switching speed of liquid crystals. This has demanded the manufacture of devices utilizing smectic liquid crystals, certain kinds of which possess a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is currently the most progressive smectic device. In it the liquid crystal molecules are set out in layers that are perpendicular to the substrate planes, which are separated by one or two micrometres, and in the layers the molecules are tilted, as illustrated in the figure. The host liquid crystal contains optically active molecules, and a slight turn up of the optical activity and the shape of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, similar to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and in the plane of the layers. So, there is a permanent charge separation over 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 right sign can reverse the direction of this dipole in tens of microseconds and by doing so reverse the tilt direction of the molecules. The respective change in optical properties can cause a change from light to dark when one or more polarizers are employed.

SSFLC devices have been produced for larger passive-matrix displays, but their cost and complex nature has stopped them from making any remarkable impact on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have shown some probability for use as parts in projection systems or as viewfinders in digital cameras. Their immediate reaction allows them to be employed in time-sequential colour systems, in which highly expensive colour filters are emulated with a coloured backlight that flashes red, green, and blue in fast succession (approx 100 cycles every second). For example, the liquid crystal might be switched to a transmissive state during the red and green periods then to a nontransmissive state during the blue period, with the outcome that the eye sees an average of red and green light, or the colour yellow.

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