Crt
Crt or Cathode Ray Tube monitors are the monitors every person will have seen before. They that look like televisions. They range in size from 15 to nearby 22 Inch, and weight up to 30 kilos.
Advantages
Great value for money
Mature technology
Good for graphical detail
Can accommodate many distinct resolutions
Disadvantages
Big
Take up a lot of space
Cost more to run than an Lcd
Lcd/Tft
Lcd or Liquid Crystal Display screens have now been nearby a few years, these are the thin screens. Some look approximately like a picture frame. You will see them referred to as Lcd or Tft (Tft being a type of Lcd). They start at nearby 14 inches, and due to technological advances bigger Lcds are being produced all the time, 30 Inch are already ready with 40 inch on the way too. They weigh very limited compared to their Crt equivalent and can be mounted on a wall or shelf with ease.
Advantages
Less desk space needed
Require less power to run, more environmentally friendly
Increased Viewable area, a 15"Lcd can give the same viewable area as a 17" Crt monitor
Disadvantages
Viewing angle can sway image quality
One native resolution
More costly than a Crt
General Monitor Features
Size
Here is one area where size does matter, the bigger the monitor the easier it will be on the eye. You will be able to open more windows and the text should be easier to read. Keep in mind the viewable area, all Crt have a smaller viewable area than their size. For Example a typical 17" Crt will have a viewable area of nearby 15.8". Lcd tends to have the same viewable area, so a 15" Lcd will have a 15" viewable area. Monitor size (and Tvs) are measured diagonally, from the top left corner to the bottom right hand corner.
Resolution
Resolution is the amount of pixels displayed on screen at one time, it's ordinarily in the format Horizontal x Vertical, e.g.?- 800x600 or 1024x768. Crt monitors can display manifold resolutions easily, while Lcd monitors are optimised for 1 native resolution (They can display other resolutions, but are optimised for 1) the higher the resolution the more you can get on screen and the sharper the image.
Crt exact Features
Dot Pitch
Dot pitch is the length in millimetres in the middle of two dots of the same colour on the screen, it's ordinarily measured diagonally and you should be seeing for something nearby 0.26mm
Refresh Rate
This is the amount of time the screen is redrawn per second, most new monitors should have inexpensive refresh rates, 75Hz or higher. Some older Crts had lower refresh rates that can cause screen flicker and induce eye strain.
Lcd exact Features
Brightness
Because Lcds require their own back light to create colour, glow is an foremost factor. It's measured in candelas per metre squared or cd/m2, where one candle produces a glow of 1 candela. The higher this number, the brighter the screen.
Contrast Ratio
This is the degree of dissimilarity in the middle of the extremes of light and dark colours. The higher the dissimilarity ratio, the more detailed the image will be. Blacks will be blacker, whites will be whiter, and particularly text on the image will be more vivid. It will ordinarily be written as 500:1 or 250:1
Response Time
Refers to just how fast a pixel can turn colour. It's measured in milliseconds with 20-30ms being the normal at the moment. Gamers and citizen who watch a lot of movies on Lcd screens would be great opting for something with a fast response time, nearby 16ms as this reduces the ghosting corollary of fast motion.
When seeing to buy a new monitor all of the above needs to be considered. Keep in mind you will be seeing at your purchase day in day out for the next few years, so do not cut corners here, buy the best you can afford, your eyes will thank you for it later.
Dead Pixel Policy
Due to the difficulties related with producing Lcd screens very few brands warrant a pixel perfect (Class 1) product,
and those that do payment a premium for it.
Most of the screens we sell currently adhere to the international standard, Iso 13406-2 and use class 2 panels.
It is possible, although uncommon, for a Class 2 Lcd screen to have a small amount of faulty pixels.
In these cases, this thorough deems the screen as being 'not faulty'.
For an Lcd monitor to be determined faulty there has to be a determined amount of dead pixels:
Acceptable malfunctioning pixels by class & type per Million pixels:
2 complete pixels enduringly illuminated (a white spot)
2 complete pixels not illuminated (a black spot)
5 sub pixels enduringly on or off or intermittent fault. May blink or show a pixel as a base colour (Red, Blue, Green, Cyan, Magenta or yellow)
or, any 2 sub pixel faults within a 5 x 5 block of pixels
Also, the faults are cumulative, so if you have 1 white spot and 1 black spot per million pixels then this counts.
Native Resolution Pixel Count Example
1024 x 768 786,432 2 or more dead pixels determined faulty
1280 x 1024 1,310,720 3 or more dead pixels determined faulty
1600 x 1200 1,920,000 3 or more dead pixels determined faulty
So, You can have a 19" Lcd monitor with a low native resolution where 2 pixels would be determined faulty, but if it had a native resolution of 1600 x 1200 and therefore had many more pixels, then 2 would not be classed as faulty.
For any Lcd to be classed as faulty it must meet the above requirements, primarily those of the exact manufacturer. Please taste the constructor directly for their current dead pixel policy.
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