The LCDs utilised for projection systems are usually small reflective or transmissive panels lit up by a forceful arc lamp source. A series of lenses expands the reflected or transmitted image and then sends it on the screen. In front-projection systems the LCD is situated on the side of the screen as the viewer, although in rear-projection systems the screen is set off from behind. Projectors of higher cost and capability sometimes utilise three separate LCD panels, casting separate red, green, and blue images that combine to reflect a coloured display on the screen.

The increasing requirement for visual displays has placed a particular emphasis on the switching speed of liquid crystals. This has led to the development of objects build with smectic liquid crystals, certain types 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 complex smectic device. In it the liquid crystal molecules are cast in layers perpendicular to the substrate planes, which are distanced by one or two micrometres, and within the layers the molecules are slanted, as displayed in the figure. The host liquid crystal contains optically active molecules, and a subtle result of the optical activity and the slant 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. Hence, there exists a permanent charge separation across the liquid crystal layer in the SSFLC, and its sign is directly coupled 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 therefore reverse the tilt direction of the molecules. The respective change in optical properties can cause a change from light to dark if one or more polarizers are used.

SSFLC devices have been produced for larger passive-matrix presentations, but their cost and complex nature has hindered them from having any remarkable movement on the market. Small transmissive and reflective active-matrix SSFLC displays, however, show some probability for use as aspects in projection systems or as viewfinders in digital cameras. Their speedy responding allows them to be utilised in time-sequential colour systems, in which highly expensive colour filters are taken out for a coloured backlight that flashes red, green, and blue in quick pulsing (approximately 100 cycles a second). For example, the liquid crystal might be switched to a transmissive state for the red and green periods 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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