Monitor Question

[JPRoy392]

What is the second value when I see a monitor for sale? They number ranges from (usually) .26-.31 . Someone told me that it is the "Aperture Grille". What does that mean?

Thank you for the help.

[barrk]

http://www.csf.org.uk/csf/dot-pitch/dotpit.htm

[HarryW]

Well, it's either 'aperture grille' (AG) or 'dot pitch' (DP), depending on the kind of monitor.

Most monitors use a shadow mask to allow light through to specific points on the phosphors of your screen (so the light is split into clear pixels). A shadow mask is like a sheet of behind your screen with lots of little holes in it. This kind of monitor is also commonly called a flatter, squarer tube, or FST (you've probably seen 'FST' in adverts before). An FST monitor has what's called a 'dot pitch', which is the distance between the holes in the shadow mask, and is also the distance between the centres of adjacent pixels. Typically this is 0.28 (in millimetres) for a 17" monitor, but can be higher or lower occasionally. Bigger monitors generally have a smaller DP, so you may see 19" models with a DP of 0.26. Smaller is better, obviously.

Diamondtron (DT) and Trinitron (TT) monitors, and other similar technologies (I think there is FlatTron too) use a different method to display pixels. They have a grille of vertical wires behind the screen which splits up the pixels. I think the red, green and blue phosphors are then stacked alternately in vertical rows so that pixels don't get blurred vertically. in order to keep them in position there are 2 (maybe sometimes more/less?) horizontal retaining wires across the grille. If you look closely at a TT/DT monitor you will see horizontal lines where these retaining wires interfere with the pixels. They are usually all but invisible, but are noticeable when they are in the middle of a solid block of colour, common in office apps. Typically, a 17" TT/DT monitor will have an AG of 0.25 (millimetres again). This is a measure of the apertures in the grille, which makes sense :) As with FST, larger monitors can often have a smaller AG, which is better.

TT/DT monitors are more expensive than FST monitors in general. TT/DT monitors are also usually much flatter, especially the latest generation of the technology, like Diamondtron NF (Naturally Flat). Diamondtron tubes are made by Mitsubishi, and Trinitron tubes are made by Sony, although they sell the tubes to other monitor manufacturers.

The two different types have different colour/contrast/clarity properties too, which I don't honestly remember right now.

Personally, I have a Mitsubishi Diamond Pro 710, which is a 17" Diamondtron NF monitor, and I am very pleased with it. The screen is completely flat.

Check reviews in magazines if you can, they often get a whole load of monitors and rate them for clarity etc. Considering you're probably buying mail order, this is very useful.