Feature: New projector technologies

If you already find yourself bemused, befuddled and bewildered by the amount of different home cinema technologies now out there in the market place, we've got some bad news for you - it's going to get worse (or better, depending on how you look at it). The choice in the projection world is no longer merely a matter of picking between DLP or LCD, as there are now three more acronyms for you to get your head around: LCOS, SXRD and D-ILA.

But before you shut your PC down in horror, you should know that these new technologies haven't just been launched to confuse you; they're actually capable of delivering some seriously impressive picture quality and specifications without breaking the bank. Plus the three technologies we're talking about actually have quite a bit in common, so adopting them into your already overflowing brainbox isn't necessarily as taxing a prospect as you might have thought.

Canon XEED SX6 £4,600 The technologies LCOS (Liquid Crystal on Silicon) LCOS, or Liquid Crystal on Silicon to give it its full name, is arguably the 'mommy' of the new projection technologies. And actually, to be honest it isn't all that new. It's been doing the rounds largely in the presentations market for three or four years, even finding its way into a rear projection TV or two in the US. But in the UK it's never really caught on as a home cinema option until recently, for a number of reasons we'll get to presently. LCOS technology is based around liquid crystals on a reflective mirror substrate, with those crystals opening or closing depending on whether the picture wants the light to be reflected from the mirror or blocked off. LCOS projectors generally use three separate mirror/liquid crystal chipsets, one for each of the core red, green and blue elements of the picture. As with LCD technology, this means the red, green and blue colour elements arrive on the screen at exactly the same time. So what are the advantages of LCOS over DLP and LCD? The first is that LCOS chipsets allow pixels to be placed extremely close together, delivering very high native resolutions and reducing the 'gaps' between pixels to such a small level that they're practically invisible in the final image. This avoids the 'grid' effect sometimes seen with LCD technology, and gets round the problems DLP has (because of its reliance on fitting mirrors onto a microchip) in showing very high resolutions. We'd also argue that the smaller pixels possible with LCOS make for slightly more natural contours and pixel edges than you can get with LCD and DLP. The fact that LCOS's approach puts reds, greens and blues on screen at once, meanwhile, rather than sequentially using a fast-spinning colour wheel arrangement as happens with DLP technology, means it avoids DLP's issues with the rainbow effect (where you can see stripes of pure colour in your peripheral vision) and motion blur/noise. The simultaneous reproduction of colours also arguably helps LCOS deliver richer, more natural colours than DLP, though Texas Instruments' new Brilliant Colour technology as found (currently exclusively) on the ProjectionDesign M20 certainly closes this gap considerably. So if LCOS is so great, how come it hasn't struck big before? There are four reasons. First, its extreme resolutions have tended to mean that it's not a cheap technology. Second, it's struggled to deliver a convincing contrast range for home cinema use, with dark parts of the picture tending to appear grey rather than black. Third, LCOS chipsets have tended for commercial reasons to come in 4:3 aspect ratios rather than the widescreen 16:9 ratio preferred for home cinema use. Finally, lamp life has tended to be rather limited versus DLP and LCD projectors - though this aspect of LCOS is fast improving. If you want to check out LCOS in action, try and get yourself a demo of the main user of the technology in the UK right now, Canon's XEED range. The naturalism of the XEED projectors pictures can be quite striking - but so, alas, can their lack of black level response and the fact that they're not produced on a native widescreen chipset. Which is why our SXRD and D-ILA contenders might actually be better bets…

Sony Ruby VPL-VW100 £6,000 SXRD (Silicon X-Tal Reflective Display) Developed by Sony and currently only found in Sony projectors, Silicon X-Tal Reflective Display (SXRD) technology is really a variant of the generic LCOS technology. But Sony's SXRD take on LCOS is notable for a number of innovations. First, groundbreaking Silicon Driving Circuitry, Silicon Wafer Process Technology, and a new Liquid Cystal Device design result in a 2.4-fold increase in pixel density and a ten-fold improvement in inter-pixel spacing. In fact, Sony claims its SXRD system delivers the smallest inter-pixel spacing in the world. Also key to SXRD's success is the way it overcomes the black level problems traditionally associated with LCOS devices. Sony has developed a unique Vertically Aligned Liquid Crystal material, where the liquid crystal molecules are aligned vertically to the cell substrates. This helps the projector enjoy improved driving voltages and higher optical properties, ensuring high contrast images that would be unachievable with conventional LCOS devices. What's more, these innovations have also helped SXRD deliver a very rapid 2.5 millisecond response time to keep the image clean and smear-free. Although SXRD only made its debut in the UK last year, it's already available on a selection of AV products, including two hugely impressive mainstream home cinema projectors, the 'Ruby' VPL-VW100 and 'Pearl' VPL-VW50, plus two outstanding rear projection TVs, the 56in KDS-56R2000 and massive 70in KDS-70R2000.

JVC DLA-HD1 £4,500 D-ILA (Direct-Drive Image Light Amplification) Direct-Drive Image Light Amplification (D-ILA) technology is another variation on the LCOS theme developed by JVC. Originally developed with even closer pixel spacing than standard LCOS, for military simulator applications, D-ILA also improves on LCOS by using vertically oriented pixels to boost contrast and adding an inorganic alignment layer that stabilises device performance - as well as making D-ILA chipsets easier and therefore more commercial to produce. These features obviously make it very close in approach to SXRD (which it actually predates). But recently JVC has added a further note of difference between its and Sony's technologies thanks to a smoothing technology that reduces irregularities in the liquid crystal alignment to reduce the amount of stray light sent bouncing around the optical array. JVC has been steadily refining its D-ILA technology for more than five years now, and earlier this year it used its latest incarnation - together with a revolutionary new 'Wire Grid Optical Engine' system that pretty much completely solves the traditional black level issues of LCOS and its variants - to produce the £4,500 DLA-HD1: possibly the finest projector we've seen this side of £10k…

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