The LCDs put for projection systems are usually small reflective or transmissive panels illuminated by a bright 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 set on the same area of the screen as the viewer, but in rear-projection systems the screen is lit from behind. Projectors of higher cost and capacity sometimes use three discrete LCD panels, reflecting separate red, green, and blue images that combine to make a coloured picture on the screen.

The increase in need for film displays has placed a growing emphasis on the switching speed of liquid crystals. This has demanded the creation of devices utilizing smectic liquid crystals, particular kinds of which emit a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this point the most developed smectic device. With it the liquid crystal molecules are cast in layers that are perpendicular to the substrate planes, which are distanced by one or two micrometres, and in the layers the molecules are tilted, as displayed in the figure. The host liquid crystal possesses optically active molecules, and a subtle outcome of the optical activity and the slant of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, comparable to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and within the plane of the layers. Thus, there exists a permanent charge separation across the liquid crystal layer in the SSFLC, and its sign is directly paired up 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 therefore reverse the tilt direction of the molecules. The consequential change in optical properties can create a change from light to dark if or when one or more polarizers are employed.

SSFLC devices have been produced for bigger passive-matrix displays, but their high cost and complex nature has stopped them from having any remarkable progress on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have displayed some possibility for use as parts in projection systems or as viewfinders in digital cameras. Their immediate responding allows them to be used in time-sequential colour systems, in which expensive colour filters are replaced by a coloured backlight that flashes red, green, and blue in quick pulsing (around 100 cycles in a second). For example, the liquid crystal might be switched to a transmissive state during the red and green periods and to a nontransmissive state for the blue period, having the result that the eye sees an average of red and green light, or the colour yellow.

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