The LCDs used for projection systems are usually small reflective or transmissive panels lit up by a strong arc lamp source. A number of lenses enlarges the reflected or transmitted image then sends it on a screen. With front-projection systems the LCD is situated on the side of the screen as the viewer, although in rear-projection systems the screen is lit up from behind. Projectors of more expense and capability can have three discrete LCD panels, creating separate red, green, and blue images that mesh to reflect a coloured picture on the screen.

The increase in demand for film presentations has had a particular emphasis on the switching speed of liquid crystals. This has necessitated the invention of items employing smectic liquid crystals, some kinds of which emit a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this time the most sophisticated smectic device. With it the liquid crystal molecules are set out in layers that are perpendicular to the substrate planes, which are differentiated by one or two micrometres, and inside the layers the molecules are on a tilt, as displayed in the figure. The host liquid crystal holds optically active molecules, and a scarcely perceptible consequence of the optical activity and the angle 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 through the plane of the layers. Hence, there exists a permanent charge separation across the liquid crystal layer in the SSFLC, and its sign is directly coupled 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 so reverse the tilt direction of the molecules. The corresponding change in optical properties can make a change from light to dark in the case that one or more polarizers are used.

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

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