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2. LCD vs. CRT
3. LCD basics
4. CRT basics
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7. Warranties
8. Monitor glossary
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You can get a lot for your money with CRTs, although they're often much bigger and heavier than LCDs. In recent years, CRT technology has advanced, so there is very little difference in performance among brands. In other words, unless you buy the absolute cheapest CRT, you should be happy with whatever you choose. Here are some key features in CRT specifications.
Bandwidth: The rate in megahertz (MHz) at which a CRT can process information. As you approach the bandwidth limit, thin black or white lines appear gray because the electron beams cannot turn all the way on or off fast enough to keep up. Generally, the higher a CRT's bandwidth is, the faster its refresh rate is at any resolution, and the better its image quality.
Convergence: Colour CRTs rely on three separate electrical beams to project simultaneous red, green, and blue images; these combine to form a full-colour image. If these beams are not precisely aligned, the red, green, and blue portions of the image may not overlap correctly; the image will look unfocused and will have visible colours along the edges. When the three beams converge correctly at all points on the display, you get a perfect image.
Maximum refresh rate: If an image refreshes too slowly on a CRT, you may notice a flicker. You want at least 70Hz at the resolution you intend to use. This becomes more of a factor as the screen size gets larger, as people are more susceptible to flicker in their peripheral vision.
Power consumption: CRT power consumption is typically specified in watts. A typical 19-inch model may draw 130 watts when operating--that's more than two standard 60-watt lightbulbs--and will generate a good deal of heat.
Screen size: CRTs specify the diagonal dimension of the entire picture tube. This is one to two inches larger than the viewable image size (also measured diagonally).
Convergence: Colour CRTs rely on three separate electrical beams to project simultaneous red, green, and blue images; these combine to form a full-colour image. If these beams are not precisely aligned, the red, green, and blue portions of the image may not overlap correctly; the image will look unfocused and will have visible colours along the edges. When the three beams converge correctly at all points on the display, you get a perfect image.
| Dot pitch: A smaller dot pitch means that a monitor can display higher-resolution images more accurately. Some manufacturers report the "horizontal dot pitch," which measures only the horizontal component of the diagonal distance between triads and offers an easier comparison to stripe-pitch measurements. |  |
Maximum refresh rate: If an image refreshes too slowly on a CRT, you may notice a flicker. You want at least 70Hz at the resolution you intend to use. This becomes more of a factor as the screen size gets larger, as people are more susceptible to flicker in their peripheral vision.
Power consumption: CRT power consumption is typically specified in watts. A typical 19-inch model may draw 130 watts when operating--that's more than two standard 60-watt lightbulbs--and will generate a good deal of heat.
Screen size: CRTs specify the diagonal dimension of the entire picture tube. This is one to two inches larger than the viewable image size (also measured diagonally).
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