A number of manufacturers are fine tuning their 3-D technology to improve picture clarity, detail and sharpness as well as providing an authentic three dimensional experience.

The important technological element of the latest approach to 3D TV involves the use of transparent cylindrical lenses known as lenticules. Lenticules are placed onto a transparent sheet, which is fixed onto an LCD. The transparency of the lenticular sheet is crucial because it allows for full brightness and contrast.

The lenticular sheet is fixed onto an LCD panel so that the image plane of the LCD is at the focal plane of the lenses. The viewer's eye observing the screen perpendicular to the display sees the portion of the LCD that is directly under each lens. The other eye, observing the screen from a different angle, sees a portion of the LCD that is off-center under each lens, the two different views creating the perception of depth.

A characteristic of all 3D displays is the tradeoff between pixel resolution and depth. This tradeoff exists because, viewed in 3D, pixels that in 2D would have contributed to high resolution are required to show depth. If the lenticular sheet were placed vertically atop the LCD, then horizontal resolution would drop by a factor equal to the number of views. A sheet of slanted lenticules, by contrast, distributes the resolution loss in the vertical and horizontal planes.

A number of manufacturers have employed slanted lenticules to increase the resolution of their 3D screens. The Dutch electronics giant Philips has recently demonstrated a 56in Quad Full HD screen which has four times the resolution of a conventional Full HD panel. The Korean manufacture LG recently unveiled a 42in prototype 3-D TV which it claims will offer resolutions comparable with today's Full HD screens.

One of the few drawbacks of the technology stems from the fact that these 3D TV's are effectively broadcasting multiple, slightly different views (through the lenticular lenses) and to pick up two different views (essential for the eye to perceive depth) the viewer needs to be sitting in a 'sweet spot' within a 135 degree viewing angle.

Philips plan to release their 56in Quad 3D screen to trade customers (for use as advertising display units) early in 2009 for around £9000.

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