CRT - LCD Comparison
The CRT is a very difficult product to replace. We will never totally replace the CRT because they are intrinsically a very simple and reliable device which have received considerable investments for improvement over the years. However, they do have their limitations.
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Positive CRT characteristics
- They create light that is Lambertian
- Fast response times
- Relatively easy to manufacture
- Images are easy to scale since they are analog
- Operates predictably in any temperature range
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Negative CRT characteristics
- Bulky size and heavy weight
- High power consumption
- Not digital devices
- Washes out in bright ambient light
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Positive LCD characteristics
- Crisp images
- Intrinsically digital
- Thin package
- Low power consumption
- Suitable for mobile applications
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Negative LCD characteristics
- Viewing angle uniformity
- Slower response times
- Limited operating temperature range
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An LCD is intrinsically a digital device and produces images that are sharp and crisp. There are no issues of linearity where you have to correct for pincushion or other types of artifacts that you will see with a CRT.
CRTs have the benefit of being very fast. CRTs can respond in microseconds. In fact one chooses phosphors with a decay time long enough so you don’t see flicker. LCDs are now converging on CRTs with response times that are under 10 milliseconds even for grayscale transforms – so acceptable video performance has just been commercialized for LCDs.
LCDs are increasing the color saturation to approach (and even surpass) the high-performance CRTs. Within a couple of years, LCDs should achieve the 80% level of NTSC – better than the 60% level of CRTs today.
The obvious advantages of LCDs are that they can be made very thin, use considerably less power, and can be made very lightweight. They are usable in applications that are impossible for CRTs because of their bulk.
Another advantage is that LCDs reflect far less light since the shadow mask of a CRT is an intrinsic reflector. When you take an LCD into an area with a high ambient light level, much less light is reflected, so it is better for applications such as ATM machines or kiosks where it is very difficult to protect a CRT from direct sunlight without turning up the brightness to extreme levels. LCDs can be made reflective or transflective to perform much better in these situations.
Environmentally, LCDs are the clear winner because of their significantly reduced power consumption. While there have been attempts to recycle CRTs, the overall benefits of LCDs in terms of energy use and the materials they are made from leads to much better environmental solutions in the long term.
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