LCD flat panel displays save space, power, and eye strain, but until recently the upfront cost has been prohibitive. As they increase in popularity and come down in price, the arguments for investing in LCDs become more compelling. Has the time come to ditch the CRT for good?
LCDs are ideal for the office environment. If, like most work PCs, your computers are used for office applications, Web-browsing and other text-intensive applications, an LCD monitor can make a great difference to your workspace. They offer a good uniform picture, good colour, and have a lot to offer in terms of space saving and ergonomics.
The best part is they are now more affordable than ever. Prices have plummeted since RMIT IT Test Labs last reviewed LCDs back in June 2000. Back then 15in displays were about $2500, and now you can pick one up for under $1000. However, this may be the bottom price for the time being. Several manufacturers expanded their production capacity in 2000-1, resulting in an oversupply, and LCDs were discounted heavilyââ,¬"more so in the US than in Australia. Some analysts are now predicting that the increased demandââ,¬"in part stimulated by Apple's new-look iMacââ,¬"could lead to shortages during 2002, and will almost certainly lead to price rises. However, the fluctuations of supply and demand are always difficult to second guess.
Advantages
LCD displays have several advantages over CRTs. One of the most compelling advantages for businesses is that LCDs take up considerably less space on desktops.
A 15in LCD display will offer roughly the same viewing area as a 17in CRT monitor. This is because a CRT monitor can't display all the way to the edge, and the edges are masked off by the monitor case. However, a 17in CRT is approximately 45cm deep, while a comparable 15in LCD is only 20cm deep. A 15in LCD weighs up to 6kg, while an average 17in CRT is over 18kg.
CRTs tend to have distorted pictures and often require fiddly adjustmentââ,¬"this can even be affected by the direction in which the CRT faces. On the other hand, LCDs are less prone to these distortions (although they are not immune). While CRTs can flicker and cause eye strain, LCDs don't have any appreciable flicker, and the image is much less harsh.
LCDs also consume less power. On average a 15in LCD consumes about 40 watts compared to 110-120 watts for a 17in CRT. This may not seem a vast difference for a single monitor, but the cost savings for 100 PCs, or 1000, would be significant. LCDs also emit less electromagnetic radiationââ,¬"15in LCDs produce around 0.1 milliGauss while a 17in CRT can produce 7 to 9 milliGauss.
On the other hand
There are also some disadvantages to LCDs. CRTs can be viewed from just about any angle, but the prime viewing angle for LCDs is considerably smaller. However, this problem has improved greatly from previous generations of LCD displays. LCDs also have less contrast: CRTs can go as high as 700:1, while even the best LCDs only can manage a contrast of 400:1. A low contrast causes darker shades to be displayed black and colour gradients to be lost.
Another major drawback of LCDs is their slow response timesââ,¬"the time they take to redraw when displaying moving pictures such as games, video, and animation. This also has improved over previous generations of LCD, to the point where most LCDs are capable of playing back video adequately, although fast-moving games are still beyond their capabilities. Of course, in a corporate environment, discouraging the use of video and games is not necessarily a bad thing.
Connectors
Since CRT monitors require an analogue signal, video cards traditionally converted the computer's digital information into an analogue signal. However, with the advent of digital LCD monitors this became unnecessary. LCD monitors that usthe analogue 15 pin mini-D-sub (standard VGA monitor) connector are in effect turning a digital signal into analogue, then back into digital. As a result they suffer from phase jitter and need to be tweaked manually for the best result. All the LCD screens we looked at had 15-pin VGA connectors. Now that the Digital Display Working Group has ratified the DVI (Digital Video Interface) standard, DVI connectors are also becoming common. DVI allows the computer to deliver a digital signal directly to your monitor. This offers a much cleaner picture, but your video card must have a DVI output for this to work.
Warranty
The most common problem with LCD displays is that individual pixels get stuck either on or off, as a result of single transistors either shorting out or failing. This can be very annoying, particularly if the stuck pixel is towards the middle of the screen. However, once the screen has been assembled, it is impossible to fix a single transistor, and the entire display must be replaced. Most vendors will not replace the display under warranty if a single pixel is stuck, and the number of dead pixels there must be before you can get the panel replaced varies greatly between manufacturers. This isn't something the manufacturers like to talk about, and we couldn't get a firm answer from any of them.
Future Trends
Manufacturers are still working on improving the viewing angle of LCDs by introducing a different type of film. We are going to see more and more displays ship with DVI connectors.
For this feature we only looked at 15in displays. We gave the opportunity to all the leading manufacturers of LCD displays to submit an LCD, and in total we received 15 displays.
Next: AG Neovo F-15
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