InFocus LP330

The modern presenter's greatest fear is that technology will let them down. Such is this concern that a new breed of projector has evolved: one that's so small and light you can happily carry your own display around with you and forget about incompatibilities.

InFocus claims its LP330 is the world's lightest 'notebook' projector, although NEC and Compaq have also since announced 'the lightest, brightest projectors on the market'. The InFocus LP330, NEC LT140 and Compaq MP1600 share remarkably similar specifications, which isn't at all surprising considering they're all based around the same technology: Texas Instrument's Digital Light Processing (DLP), which employs a matrix of tiny mirrors to reflect light, as opposed to the grid of crystals and filters through which light is shone in an LCD projector. All three models feature a high native XGA resolution of 1,024 x 768 pixels.

One big advantage of DLP is that the gaps between adjacent pixels are much smaller than those with LCDs - the result being less 'dead' area where no light is present, and an image with less of a pronounced grid effect. Single-chip DLP projectors also boast smaller optical assemblies than three-chip LCD projectors, which is why it's the technology of choice in ultra-portables.

Size and weight are obviously critical measurements for ultra-portable projectors, and today you'll be paying a significant premium for the privilege. The three models from InFocus, NEC and Compaq all carry price tags around £5,000 excluding VAT, which is almost double the price of equivalently specified transportables. However, place them side by side and the physical difference is astonishing. While most transportables measure around 150 x 300 x 400mm and weigh between 4 and 7kg, the InFocus LP330 is a tiny 64 x 229 x 267mm and weighs only 2.2kg. Compaq's MP1600 is fractionally smaller at 63 x 209 x 228mm and slightly lighter too at 1.9kg, while NEC's LT140 is a tad bigger at 58 x 235 x 298mm and the heaviest of the three at 2.6kg. While there's about a pound of weight difference between each model, none of them can be described as a burden to carry around.

However, despite the weight similarities, they do look quite different from the outside. The InFocus is curvey, the NEC boxy, and the Compaq retro.

Interestingly, all three manufacturers cite looks as very important to the whole experience and the impression audiences have of their presenter, so choose carefully. More importantly, InFocus and NEC share a flat design, whereas the Compaq stands up. Since the flat models use 100 per cent image offset, the bottom of the picture is in line with the bottom of the lens. This means you don't need to raise the projectors above the surface of a desk for an unobstructed view.

All models feature extending front feet, although angling the lens upwards introduces keystone distortion, with the top of the image being wider than the bottom. Both the NEC and Compaq feature keystone correction, but the InFocus does not. So saying, in the environments an ultra-portable will be used, significant keystone correction shouldn't be necessary and, besides, over correction of a digital projector reduces image quality.

Brightness is an essential specification, literally defining the maximum image size and amount of ambient light that can be overcome. Compaq offers 600, InFocus squeezes 650 and NEC boasts an impressive 800 ANSI Lumens of light output. While the NEC is the brightest, all three have sufficient output to produce a good-looking 4ft to 5ft image under fair daytime conditions.