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The LCDs built for projection systems are generally small reflective or transmissive panels illuminated by a bright arc lamp source. A number of lenses expands the reflected or transmitted image and casts it on the screen. In front-projection systems the LCD is situated on the same area of the screen as the viewer, while in rear-projection systems the screen is set off from behind. Projectors of higher cost and capability can utilise three separated LCD panels, forming separate red, green, and blue images that mesh to make a coloured picture on the screen.

The increase in demand for visual displays has had a growth in emphasis on the switching speed of liquid crystals. This has led to the development of devices utilizing smectic liquid crystals, certain types of which possess a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is in the current day the most complex smectic device. Inside it the liquid crystal molecules are arranged in layers perpendicular to the substrate planes, which are differentiated by one or two micrometres, and within the layers the molecules are on a tilt, as demonstrated in the figure. The host liquid crystal has optically active molecules, and a slight result of the optical activity and the shape of the molecules is the appearance 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 in the plane of the layers. Hence, there exists a permanent charge separation over 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 correct 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 make a change from light to dark when one or more polarizers are used.

SSFLC devices have been marketed for larger passive-matrix presentations, but their cost and complex detail has stopped them from making any particular movement on the market. Small transmissive and reflective active-matrix SSFLC displays, however, show some probability for use as elements in projection systems or as viewfinders in digital cameras. Their immediate reaction allows them to be utilised in time-sequential colour systems, in which highly expensive colour filters are replaced with a coloured backlight that flashes red, green, and blue in fast pace (approx 100 cycles every second). For example, the liquid crystal may be switched to a transmissive state for the red and green periods then to a nontransmissive state in the blue period, displaying the end result that the eye sees an average of red and green light, or the colour yellow.

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