The LCDs utilised for projection systems are usually small reflective or transmissive panels set off by a bright arc lamp source. A number of lenses enlarges the reflected or transmitted image and casts it onto the screen. With front-projection systems the LCD is placed on the same side of the screen as the viewer, although in rear-projection systems the screen is lit up from behind. Projectors of greater expense and performance can use three distinct LCD panels, creating separate red, green, and blue images that combine to create a coloured display on the screen.

The growing need for pictographic displays has had a particular emphasis on the switching speed of liquid crystals. This has necessitated the invention of items utilizing smectic liquid crystals, particular types of which have a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this time the most developed smectic device. Inside it the liquid crystal molecules are arranged in layers perpendicular to the substrate planes, which are separated by one or two micrometres, and within the layers the molecules are on a slant, as illustrated in the figure. The host liquid crystal contains optically active molecules, and a slight outcome of the optical activity and the angle of the molecules is the appearance 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 throughout the plane of the layers. Hence, there must be a permanent charge separation over 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 so reverse the tilt direction of the molecules. The consequential change in optical properties can cause a change from light to dark if or when one or more polarizers are employed.

SSFLC devices have been produced for big passive-matrix presentations, but their expense and complex detail has stopped them from having any particular effect on the market. Small transmissive and reflective active-matrix SSFLC displays, however, display some possibility for use as parts in projection systems or as viewfinders in digital cameras. Their immediate responding allows them to be made use of in time-sequential colour systems, in which dear colour filters are emulated by a coloured backlight that flashes red, green, and blue in fast succession (approximately 100 cycles a second). For example, the liquid crystal can be switched to a transmissive state in the red and green periods and then to a nontransmissive state in the blue period, creating the result that the eye sees an average of red and green light, or the colour yellow.

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