The LCDs utilised for projection systems are typically small reflective or transmissive panels lit up by a forceful arc lamp source. A number of lenses magnifies the reflected or transmitted image then casts it on the screen. With front-projection systems the LCD is located on the side of the screen as the viewer, while in rear-projection systems the screen is set off from behind. Projectors of greater cost and performance can use three separated LCD panels, reflecting separate red, green, and blue images that mesh to reflect a coloured picture on the screen.

The growth in need for video presentations has put a special emphasis on the switching speed of liquid crystals. This has necessitated the manufacture of items using smectic liquid crystals, certain ones of which possess a quicker electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this point the most sophisticated smectic device. In it the liquid crystal molecules are set out in layers that are perpendicular to the substrate planes, which are separated by one or two micrometres, and throughout the layers the molecules are slanted, as shown in the figure. The host liquid crystal contains optically active molecules, and a subtle outcome of the optical activity and the shape 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 in the plane of the layers. Therefore, there must be a permanent charge separation across 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 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 effect a change from light to dark if one or more polarizers are utilised.

SSFLC devices have been publicized for larger passive-matrix presentations, but their expensiveness and complexity has impeded them from having any particular movement on the market. Small transmissive and reflective active-matrix SSFLC displays, however, show some probability for use as parts in projection systems or as viewfinders in digital cameras. Their immediate reaction allows them to be made use of in time-sequential colour systems, in which highly expensive colour filters are emulated with a coloured backlight that flashes red, green, and blue in rapid pulsing (around 100 cycles per second). For example, the liquid crystal can be switched to a transmissive state during the red and green periods and then to a nontransmissive state in the blue period, creating the end result that the eye sees an average of red and green light, or the colour yellow.

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