Monitor Specs

Article Type: 
FAQ

This is meant to be general info about TFT and not about spesific monitors or brands - as objective a view as possible. Among other things, I will include a section about the different panel technologies and their pros and cons.

A quick recap of terminology for techs and specs. Explanations and what they mean put to practial use:


Brightness

Brightness is measured in candelas per meter squared (cd/m2). High brightness capabilities can be good for viewing video, playing games and general use. However, too high brightness can also increase stress level, give poor focus and loose some image contrast. Brightness is especially useful when adjusting the screen to the enviroment. Very bright enviroment tend to dim out the screen. Adjusting brightness is usually best to do by hardware (OSD) then through software to reduce washing out the colors. The importance of brightness is mainly determened by your enviroment. Brightness should be adjusted in conjunction with contrast.


Contrast Ratio

Contrast ratio is the difference between the brightest white and the darkest black. 500:1 means its 500 times darker then white. Higher number usually means better image and easier to read text. However, you must take into consideration that the contrast sensitivity of your eyes are about 300:1. Still, the enviroment plays a big part here and higher ratio gives more oportunity to adjust accordingly. Contrast should be adjusted in conjunction with brightness.


Diagonal Size

Measured in inches diagonally. Bigger is NOT nessesarily better! It all depends on what you will use it for and the distance you will have between you and the TFT. When far away, big is best. Closer up you will want high resolution and small pixel pitch.


Pivot

The ability to rotate the monitor from landscape to portrait view. Very useful for reading/editing a lot of text.


Pixel Pitch

The pixel pitch is measured in mm and the size depends on the resolution used. Lower number means sharper image. Since TFT has a fixed number of pixels, all TFT's at the same size and resolution has the same pixel pitch. So, why do they write the size on the specs?

As an example: Brand A is a 23" TFT with a native resolution of 1920*1200. Brand B is a 23" TFT with a native resolution of 1920*1200. Both have a pixel pitch of 0.258 mm. Brand C, however is a 24" TFT with a native resolution of 1920*1200 and its pixel pitch is 0.270 mm. For you this will mean that the 24" will give you a larger screen at the cost of picture sharpness. On bigger screens, the pixel pitch would play a much larger role.


Refresh Rate

Unlike CRT which need a constant redrawing of the picture, the TFT's refresh rate isn't so much of importance. This is because the pixels stands still until they are asked to be moved. On TFT you need to look for lower response time instead of higher refresh rates.


Resolution

Resolution is described by the columms and rows of pixels that can be displayed. (1920 columms * 1200 rows of pixels). TFT's are a fixed-matrix display. That means they have an exact number of pixels on a screen, unlike CRT which adjust the size of the pixel according to need. This gives the TFT an advantage over the CRT in providing a crispy clear image at native resolution.

However, at non-native resolutions, the TFT needs to use complex algorithms by doubling and dividing the pixels in different ways in order to display the selected resolution. This might result in different degrades in the picture at none native resolutions. Usually higher resolution is better, provided that your machine is capable of running such resolutions.


Response Time

Response time is measured in milliseconds. There are two parameters quantifying the response time: gray to gray and black to white. Unlike CRT, the TFT pixels stays put until they are asked to change. The gray to gray measures how fast one pixel turns from one color shade to another of the same color. The black to white measures how fast one pixel can turn to another color. Lower response time is better. This is very important when using the screen to watch video and play games, and has been one of the factors the hard core gamers consider when going from CRT to TFT. Be very careful when reading manufacturer specs on response time. Many will not indicate whether they are measuring gray to gray, or black to white. Also, there is no consistent way to measure response time, so one manufacturers 8ms will not necessarily be the same as another. Your best bet is to see the panel in question.


Viewing Angle

The viewing angle is measured in degrees and shows you how big angle you can watch the screen on without getting a picture distortion. Its important to have a big viewing angle for many purpouses. If you pivot the monitor, if several are watching the same monitor and if you need to see the picture from different angles.