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Are these available anywhere yet?



LCOS (Liquid Crystal on Silicon) technology, a souped-up derivative of LCD technology, is the hot new kid on the block in high-resolution displays. Rather than passing light through a transparent LCD panel to generate an image, in LCOS displays the light is bounced off of a reflective substrate onto which liquid crystals have been applied. There are two classes of LCOS light engines: single-chip and three-chip. In a single-chip system, light is filtered through a color-wheel system similar to that employed by DLP projection systems. The sequence of colors produced is then temporally coordinated with the modulation of light by the liquid crystals, producing subtle color variations. Three-chip displays use a system of prisms to split a single light source into its red, green and blue components (analogous to the three tubes in a CRT projection system). Discrete video modulations are applied individually to the three resulting light paths, which are then recombined by another prism array to create the composite image. LCOS technology is used in displays of 50" and larger.


Strengths

LCOS' calling card is ultrahigh resolution. A typical high-resolution LCOS panel comprises 1080 pixels x 1920 pixels, making it the first fixed-pixel imaging system capable of faithfully reproducing every detail in a 1080-line image (LCD and plasma HD panels typically "scale," or interpolate, 1080-line images in order to display them in the panels' 1024 actual lines). Additionally, among current technologies, LCOS is uniquely capable of upconverting a 1080-line interlaced image (1080i) for true progressive-scan display (1080p). Visible pixelization (known as "screen-door effect") is virtually eliminated at normal viewing distances with LCOS, because the cell structure of the panels features very little space between the individual pixels. And because the light passes through the liquid crystals twice on its way to the projection lens (once between lamp and mirror, and once more when reflected back toward the projection lens), LCOS improves upon the traditionally marginal contrast performance of LCD displays, while sharing LCD's imperviousness to burn-in.


Considerations

Because they generate color in much the same way as DLP projection systems, single-chip LCOS systems can share DLP's problem of "rainbow effect" artifacts. Most viewers won't even notice this anomaly, but to those sensitive few who do, it can be a real distraction. Conversely, 3-chip LCOS systems avoid the rainbow effect, but rely on very precise calibration in the manufacturing process to accurately recombine the color components into a sharp, seamless on-screen image. Since such calibrations are inherently imperfect (if only to a miniscule degree), 3-chip systems may suffer very slightly in the sharpness category — but since the light is separated and recombined by a fixed prism system, periodic user calibrations to maintain convergence are unnecessary. As with traditional LCD technology, pure, inky blacks are a weakness of LCOS displays — but as with LCD, recent refinements have improved LCOS' performance in this regard.


The bottom line

Overall, LCOS earns its pervasive buzz as a technology that may be the heir apparent to CRT projection for large-screen TVs, both high-definition and standard-definition. Its many advantages are balanced by bulk (cabinet dimensions similar to DLP units — slimmer than CRT projection but not as sleek as LCD or plasma) and weight (several hundred pounds is not uncommon). But if you want to feel like you're "looking out a window" while viewing your big-screen HDTV, LCOS' ultrahigh resolution and virtually invisible pixelization may be your dream come true.
 

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You are in the wrong subforum, as LCoS is rear projection. And yes they are available, as JVC uses a form of it called DILA in their rear projection sets. Lots of threads on it in rear projection. I think sony uses a form of it too, but I'm not positive. There are other smaller makers too, I think syntax has a LCoS set.


Check out TVA for the JVC models.
 
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