Difference Between LCD & Plasma Displays

Differences in technology lead to differences in performance between plasma and LCD TVs.

Flat panel televisions have led to an explosion in installation possibilities and introduced big-screen sets in places previously impossible. Although small differences exist between LCD and plasma TVs, those differences lead to markedly different appearance when viewed on a showroom floor or in the home. Regardless of the technology you choose, either is sure to produce fantastic images in nearly any room in the house.

LCD Television

Liquid crystal sets are virtually immune from image retention, also known as burn-in. Burn-in can occur when a high-contrast, static image (like a PC's task bar) is left in place for an extended duration. Images are created by either a fluorescent-style cold-cathode bulb or light-emitting diode backlight that shines through the individual liquid crystal cells. These color cells open and close at various intervals, blocking light to create black and addressed to the correct pixels to generate a vibrant image. Most LCD TVs are a little poorer in performance if the viewer is not directly in front of the set; viewers may see reduced black levels. This is mitigated by the tendency to have less screen reflection and overall brighter light output.

Plasma Displays

Plasma sets operate by allowing electrical current to excite internal inert gases (such as xenon and neon), illuminating the individual color-generating chemicals, known as phosphors. This creates a bright, colorful and engaging experience, simulating a flatter tube TV in performance and black level. Although it is possible to "burn in" an image, this requires a little effort and lack of attention paid to the display. In addition, rarely is this a permanent problem, and can be alleviated by continuing to play non-static images until the issue resolves itself.

Weight Considerations

LCD sets are generally lighter than plasma, given the lack of glass layers present in plasma. Plasmas must incorporate at least two glass panels internally, configured in a "sandwich" to constrain the internal gasses and phosphor cells.

The Green Movement and Flat Panels

Energy Star compliance and general consumer demand have created a situation where flat panel sets are less power hungry, without hampering picture quality. Although neither display is problematic in terms of standby power usage or while viewing, LCDs might be a superior choice for consumers looking to shave resource consumption for all household appliances. Occasionally, governments will offer tax incentives to consumers purchasing products that are known to be more energy efficient. LCDs are also a little cooler during operation, leading to potentially lower operating costs. Plasmas do indeed run warmer than LCD sets, although year by year, that gap in cool-running performance and energy efficiency between the two technologies is shortened.

All Shapes and Sizes

For home theater and media-room applications, plasma sets have attempted to position themselves as the performance leader. Known for superior black levels and contrast, plasma sets mimic traditional CRT in terms of picture quality, only thinner. With very few exceptions, plasmas begin at 42 inches, capping at 100 inches (as of March 2010) for the most avid home-theater enthusiast, and for professional media applications. LCD however has been proven to be superior for family-friendly whole-home usage, able to display video games and news broadcasts without risk of damage from burn-in. Additionally, LCDs come in sizes ranging from 15 inches all the way to 65 inches diagonally.

References

• Plasma TV Science: Inner Workings of Plasma Displays
• Bit-Tech.net: How CRT and LCD Monitors Work

Resources

• CNET: Four Styles of HDTV-CNET