The LCDs utilised for projection systems are generally small reflective or transmissive panels set off by a powerful arc lamp source. A line of lenses magnifies the reflected or transmitted image and then displays it onto the screen. For front-projection systems the LCD is located on the side of the screen as the viewer, although in rear-projection systems the screen is lit up from behind. Projectors of greater cost and capacity can use three separate LCD panels, reflecting separate red, green, and blue images that come together to create a coloured display on the screen.

The growing demand for pictographic presentations has granted a growing emphasis on the switching speed of liquid crystals. This has necessitated the invention of objects build with smectic liquid crystals, particular types of which possess a better 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 managed in layers that are perpendicular to the substrate planes, which are distanced by one or two micrometres, and inside the layers the molecules are tilted, as shown in the figure. The host liquid crystal contains optically active molecules, and a minor result of the optical activity and the angle 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. So, there is a permanent charge separation throughout 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 right sign can reverse the direction of this dipole in tens of microseconds and in so doing reverse the tilt direction of the molecules. The resultant change in optical properties can create a change from light to dark if one or more polarizers are utilised.

SSFLC devices have been marketed for larger passive-matrix presentations, but their cost and complex detail has hindered them from having any remarkable progress on the market. Small transmissive and reflective active-matrix SSFLC displays, however, have some possibility for use as parts in projection systems or as viewfinders in digital cameras. Their speedy reaction allows them to be utilised in time-sequential colour systems, in which dear colour filters are emulated with a coloured backlight that flashes red, green, and blue in quick pulsing (around 100 cycles a second). For example, the liquid crystal may be switched to a transmissive state during the red and green periods and then to a nontransmissive state during 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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