The Difference Between CRT & LCD Televisions
Manufacturers produce televisions using a variety of technologies. CRT (cathode ray tube) and LCD (liquid crystal display) are two of the most popular TV technologies. Karl Braun invented the CRT oscilloscope in 1897, but televisions did not use the technology commercially until 1931. Since then, CRT TVs have enjoyed widespread use. In contrast, George Heilmeier discovered LCD technology in 1964. LCD technology only became popular for televisions in the 1990s. While both technologies work well, there are several differences between them.
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Technology
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Cathode tube CRT televisions work by firing electrons down a cathode ray tube. These electrons pass through a filtered grid and react with a phosphorus coating on the inside of the TV screen. This interaction produces the colored TV images. In contrast, LCD televisions use liquid crystals between two plates. They work by using a back-light to illuminate millions of tiny pixels. A transistor controls each pixel, and each pixel has a polarized glass filter behind it. This filter controls the amount of light emitted by the pixel, producing the image seen on the screen.
Energy Efficiency
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Power consumption CRT televisions consume more energy than an LCD television. According to Energy Star, CRT televisions use up to 50 to 70 percent more energy than an LCD TV of the same size. As a result, LCD televisions are more environmentally friendly.
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Screen Resolution
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Screen resolution is the measure of the vertical and horizontal pixel dots per square inch. CRT screens can display multiple resolution types, which allows for a customized viewing experience. LCD screens can typically only display one resolution at its full screen size.
Price Comparison
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Price comparison CRT televisions are less expensive than LCD TVs. According to a price study performed by DisplaySearch.com in 2007-2008, CRTs are still less expensive, although the pricing gap is narrowing. CRT TVs cost less to manufacture due to the older technology. LCD is a newer technology, and the higher prices help cover high manufacturing and research costs.
Viewing Angles
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CRT televisions have a wider viewing angle than most LCD displays. When viewing a CRT television from an extreme angle, the picture quality remains stable. In an LCD television, the image fades at extreme angles.
Size Differences
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CRT TV CRT televisions are typically much larger and heavier than LCD TVs. CRTs must have a large space for the cathode ray tube and other internal electrical components important to their operation. In contrast, LCD televisions can be less than 1/2 inch thick in some applications due to the small film of pixels and liquid crystal compounds.
Health Considerations
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CRT televisions emit various types of electromagnetic field radiation (low frequency), which may be harmful under extended exposure. LCD televisions emit a significantly lower amount of radiation. CRT televisions also rely on a constant flash of electrons to illuminate the screen, which causes a flicker. Over time, this can cause increased eyestrain and headaches for users. LCD screens do not flicker.
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