The LCDs built for projection systems are most often small reflective or transmissive panels lit up by a strong arc lamp source. A number of lenses enlarges the reflected or transmitted image and then displays it on the screen. With front-projection systems the LCD is located on the same side of the screen as the viewer, while in rear-projection systems the screen is illuminated from behind. Projectors of greater cost and performance can utilise three separated LCD panels, casting separate red, green, and blue images that combine to make a coloured display on the screen.

The increase in demand for film displays has placed a growing emphasis on the switching speed of liquid crystals. This has led to the development of objects build with smectic liquid crystals, some kinds of which give a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is in the current day the most developed smectic device. Within it the liquid crystal molecules are set out in perpendicular layers to the substrate planes, which are separated by one or two micrometres, and inside the layers the molecules are on a tilt, as displayed in the figure. The host liquid crystal contains optically active molecules, and a scarcely perceptible turn up of the optical activity and the angle of the molecules is the presence of a permanent charge separation, or ferroelectric dipole, analogous to the ferromagnetic dipole of a magnet. The direction of this dipole is perpendicular to the tilt direction of the molecules and throughout the plane of the layers. Hence, there is a permanent charge separation throughout 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 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 create a change from light to dark if or when one or more polarizers are employed.

SSFLC devices have been publicized for larger passive-matrix displays, but their cost and detail has prevented them from enjoying any significant progress on the market. Small transmissive and reflective active-matrix SSFLC displays, however, show some promise for use as parts in projection systems or as viewfinders in digital cameras. Their speedy response allows them to be utilised in time-sequential colour systems, in which high cost colour filters are replaced by a coloured backlight that flashes red, green, and blue in fast speed (about 100 cycles every second). For example, the liquid crystal might be switched to a transmissive state during the red and green periods and to a nontransmissive state in 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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