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The LCDs used for projection systems are usually small reflective or transmissive panels lit by a strong arc lamp source. A line of lenses expands the reflected or transmitted image then displays it on a screen. With front-projection systems the LCD is situated on the same side of the screen as the viewer, while in rear-projection systems the screen is lit up from behind. Projectors of more expense and capability sometimes utilise three discrete LCD panels, reflecting separate red, green, and blue images that combine to reflect a coloured picture on the screen.

The increasing requirement for film displays has placed a particular emphasis on the switching speed of liquid crystals. This has led to the development of devices using smectic liquid crystals, particular kinds of which have a quicker 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 set out in layers perpendicular to the substrate planes, which are differentiated by one or two micrometres, and in 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 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 through the plane of the layers. Therefore, there has to be a permanent charge separation throughout 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 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 respective change in optical properties can effect a change from light to dark in the case that one or more polarizers are utilised.

SSFLC devices have been commercialized for big passive-matrix presentations, but their expense and detail has hindered them from making any particular progress on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have some possibility 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 highly expensive colour filters are replaced with a coloured backlight that flashes red, green, and blue in quick speed (approximately 100 cycles in a second). For example, the liquid crystal might be switched to a transmissive state for the red and green periods and then to a nontransmissive state for the blue period, creating the outcome that the eye sees an average of red and green light, or the colour yellow.

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