Hitachi CML181SXW

Last year, Hitachi stepped away from developing CRT-based products to concentrate on TFT technology. One of the latest developments out of the Hitachi camp is Super IPS, a new version of its ageing Super TFT or IPS (In Plane Switching) technology.

Hitachi developed Super TFT to improve poor viewing angles. In a conventional TN (Twisted Nematic) panel, the molecules rotate with varying levels of twist, depending on the distance from the electrode on each glass plate. Super TFT uses a pair of electrodes that lie parallel to the molecules and also to each other and the glass. As the molecules are more uniformly aligned, changes in the refractive index at increasing angles are decreased, reducing colour shift. The molecules can also spin, dispersing the light and improving viewing angles.

Super IPS takes this further by using a new electrode structure that angles the orientation of the electric field to help reduce colour shifts even more. Super IPS also claims to improve colour uniformity across the screen.

Even more impressive is the fact that Hitachi's claims appear to be justifiable. Connected to the DVI output of a GeForce4 Ti 4600 graphics card, the CML181SXW was wonderfully bright and sharp, with vivid colours. Viewing angles were tremendous too, and the screen was easily visible viewed almost side on. The contrast drops at greater angles, but colour uniformity and brightness still appear even - a truly superb achievement.

The CML181SXW also handled the DisplayMate Multimedia Edition tests well at its native resolution of 1,280 x 1,024. Colour performance was excellent, with smooth fades and good high-end greyscale and colour extension. Response times were also up to scratch, and the CML181SXW had no problem playing DVDs or fast-paced 3D games.

However, low-end greyscale extension was slightly truncated and primary colours didn't fade evenly. In addition, we noticed some minor colour timing issues, where adjacent blocks of colour bled into each other slightly, and low-resolution scaling wasn't the best we've seen. That said, these are fairly minor issues and the CML181SXW is an otherwise superb performer, beating the LG Flatron L1800P (see Reviews, issue 91, p132) in terms of image quality.

Image quality aside, the CML181SXW has a few other issues, the main one being poor performance with an analog signal. Switching to the D-SUB output of the GeForce4 resulted in a massive drop in sharpness, which couldn't be properly compensated for. The message is clear - don't buy this monitor unless you have a DVI-capable graphics card.

Adjusting the colour balance was problematic - although there's an RGB setting in analog mode this disappears under DVI. For most graphics cards, though, you can adjust the screen through the Display Properties panel.

The Hitachi CML181SXW is a superb TFT and certainly one of the best 18in panels we've seen. However, despite a pair of stereo speakers, the lack of a USB hub or portrait facility means it's pretty basic. It also looks quite dated next to the latest thin-bezel designs. More importantly, though, the image quality and viewing angles are both top notch, providing you use DVI.

Author: Gareth Ogden