The LCDs utilised for projection systems are generally small reflective or transmissive panels lit by a forceful arc lamp source. A number of lenses enlarges the reflected or transmitted image and displays it onto the screen. In front-projection systems the LCD is situated on the same side of the screen as the viewer, although in rear-projection systems the screen is set off from behind. Projectors of more expense and performance sometimes utilise three separate LCD panels, casting separate red, green, and blue images that combine to form a coloured display on the screen.

The increasing need for visual presentations has placed a growth in emphasis on the switching speed of liquid crystals. This has demanded the invention of objects employing smectic liquid crystals, particular types of which give a faster electro-optical response than nematic liquid crystals. The surface-stabilized ferroelectric liquid crystal (SSFLC) display is at this point the most sophisticated smectic device. With it the liquid crystal molecules are arranged in perpendicular layers to the substrate planes, which are differentiated by one or two micrometres, and in the layers the molecules are on a tilt, as shown in the figure. The host liquid crystal holds optically active molecules, and a minor outcome of the optical activity and the slant of the molecules is the appearance 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 through the plane of the layers. Therefore, there has to be a permanent charge separation over the liquid crystal layer in the SSFLC, and its sign is directly attracted 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 hence reverse the tilt direction of the molecules. The respective change in optical properties can make a change from light to dark in the case that one or more polarizers are utilised.

SSFLC devices have been produced for large passive-matrix presentations, but their expensiveness and complexity has stopped them from enjoying any significant progress on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have shown some probability for use as aspects in projection systems or as viewfinders in digital cameras. Their quick responding allows them to be made use of in time-sequential colour systems, in which expensive colour filters are emulated with a coloured backlight that flashes red, green, and blue in rapid speed (around 100 cycles per second). For example, the liquid crystal may be switched to a transmissive state between the red and green periods and then to a nontransmissive state during the blue period, displaying the upshot that the eye sees an average of red and green light, or the colour yellow.

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