LCD HDTV: Questions Answered

With the holidays coming up, many people are looking to replace their old televisions with new flat panels, and many HDTV owners are simply wanting to upgrade to a larger size. In order to make shopping easier for you, we have listed some key facts on LCD displays and TV/monitor resolution from Samsung to help you choose the best television for your lifestyle and budget.

1) Which resolution is better for viewing HDTV and do all TV displays have the same resolutions?

• Full HD is 1080p (p for progressive), but there are other resolutions for “hi def.” A display is considered “hi def” if it is wide screen and in either 720p, 1080i (i for interlaced) or 1080p format. All flat-panel display technologies have these hi def resolutions, including LCD, plasma, and DLP.
• The best HDTV viewing is at 1080p, which is available with HD-DVD and Blu-Ray players as well as XBOX 360, Playstation 3 and other gaming consoles. However, hi def TV programming is broadcast at 720p and some 1080i. Both 1080i and 1080p (1920 pixels by 1080 pixels) provide a distinctly sharper picture with 1080 lines of vertical resolution rather than the 720 lines that appear with 720p (1280x720 pixels). For context, standard TV has about 480 lines of resolution. Of the two 1080 standards, 1080p is superior to 1080i because the “interlaced” displays employ a different method of painting the screen with lines of resolution, resulting in a slight degradation in picture quality compared to progressive displays.

• Progressive-scan HDTV displays show fewer annoyances involving motion (referred to as motion artifacts), such as jagged diagonal lines and blurred movement in finely detailed areas. They make a smoother video image that stays sharper during motion than an interlaced one. LCDs are offered in far more 1080p-consumer products than plasma displays.
• When shopping, consumers should look for availability of a HDMI (High-Definition Multimedia Interface) connector. This will ensure full video and audio compatibility with HDTV sources such as HD digital cable boxes, HD satellite receivers, and HD DVD and Blu-ray Disc players.
  

2) What are some of the benefits of liquid crystal displays or LCDs?

• LCD screens are easier than any other display technology to view in brightly lit rooms, so you don’t have to turn off the lights or shut the curtains to view your PC monitor or TV. But if you prefer a darker setting, LCDs show images just as well in low lighting.
  
• LCDs with full high-definition (FHD) images come in a variety of screen sizes that have up to six times the resolution of standard TV broadcasts and twice the resolution of most 40-inch class plasma TVs. About 60% of the LCD TVs sold in the USA in 2006 had FHD features.
  
• LCDs are thinner and lighter than comparably sized projection screens – important for wall-mounted flat panel TVs, as well as mobile phones.
  
• Life span, the number of viewing hours a television provides before dimming to half brightness, is one of the biggest advantages LCD technology has. Though the numbers vary among different brands, LCD and plasma TVs generally provide the most hours of flat panel viewing time, up to 50,000-60,000 hours before dimming.
  

3) In the past, LCD screens have been criticized for low color contrast, limited viewing angles and some blurriness during fast-action scenes. Are these perceptions still accurate?

• Low-color contrast and limited viewing angles are legacy issues that have long been corrected. In addition, that barely noticeable motion blur also will be a thing of the past for most LCD TVs being produced, by early 2008.
  
• New technological advancements such as “120Hz high-speed driving” and motion compensated frame interpolation led by Samsung’s McFi™ technology have been introduced that make fast-action scenes look exceptionally clear and virtually free from blur.
• New advancements in LCD technology now allow for the widest possible viewing angle – up to 180 degrees.
  
• Further advancements are coming that will dazzle viewers like extremely high dynamic contrast ratios (such as 50,000:1 or 100,000:1) and ‘instant on’. Today, there is more R&D and production investment in LCD than all other display technologies combined. Those investments ensure that LCD technology is constantly improving.
  

4) How wide is a good viewing angle?

• It is becoming increasingly common for more than one person to view the screen on a portable electronics device or monitor at the same time, and for a TV, the number of simultaneous viewers can be as many as 5-6 in a common living room. In the past, a viewing angle of 80-100 degrees was typical for many hand-held devices and 100-150 degrees for TVs. Today consumers should look for a viewing angle between 170 and the maximum of 180 degrees.
  

5) Shoppers have heard about the “burn-in” problem associated with some flat panel televisions. What is that?

• Burn-in – technically called “phosphor burn-in” – is a permanent disfigurement of areas on a phosphor-based display such as in older plasma TV displays (Samsung and most other newer models have resolved this problem) or in CRT monitors. Burn-in occurs when static or unmoving images stay onscreen for a prolonged period of time. This can happen, for example, with video gaming or DVD “start up” screens staying on for hours at a time repeatedly.
  
• LCD screens are not phosphor-based, so there is no permanent phosphor burn-in problem. While LCDs are not susceptible to burn-in, faint images or color-distortion could persist after a non-moving picture stays on screen over a long period of time. But unlike burn-in, such image persistence can usually be corrected. Best to avoid the possibility by simply shutting off the TV when you leave it for a good while, or adding a screen saver to a monitor.
  

6) Can shoppers view HDTV channels automatically when they purchase an HDTV?

• No. Many consumers think they’ll get HD programming by purchasing an HDTV. Not the case – you have to subscribe to an HD service. According to the Leichtman Research Group, reportedly only 50 percent of HDTV owners subscribe to an HD service, and 25 percent believe they are watching programs in HD when they are not. After buying an HDTV, viewers will need to contact their cable or satellite provider to receive the rich HD content offered on some channels.
  

7) What do shoppers need to know about “contrast ratio”?

• Contrast ratio measures luminosity, or difference in brightness between the brightest white and the darkest black. The higher the contrast ratio, the better. Contrast ratio is unaffected by screen size.
• TV buyers should be aware of two kinds of contrast ratios: static and dynamic. Static contrast refers to the direct ratio between the brightest and the darkest color a TV is capable of producing simultaneously at any instant of time. Dynamic contrast refers to the ratio achieved when luminosity is combined with standardized calculations that adjust for more popular darker room settings– usually used in rating brightness levels for LCD and plasma TVs. Comparing static and dynamic contrast is like comparing apples and oranges.
  
• Often manufacturers don’t state whether they’re providing a static or dynamic contrast ratio. The size of the number should be an indicator however. Dynamic contrast is measured in much larger numbers (3000:1 up to 15,000:1), while static is usually in the range of 500:1 up to 2000:1.
  
• Bottom line: the newest LCD technology tends to have the highest contrast ratios, followed closely by plasma sets.
  

8) How does aspect ratio differ from contrast ratio?

• Aspect ratio describes the relationship of screen width to screen height, not the level of brightness contrasted between dark black and bright white. Aspect ratio measures size of your viewing image with 4:3 the typical size for standard TVs and 16:9 the typical size for the wider, theatre-like dimensions of HDTVS and widescreen monitors.
  
• DVDs typically look better on wide-screen displays because nearly every movie made in the last 50 years was filmed in a wide-aspect-ratio format. With the emergence of HDTV, people in rapidly increasing numbers are venturing away from the standard 4:3 display ratio of traditional computers and TVs to alternate aspect ratios, which have a more rectangular look
  

9) Power consumption and “clean” technology are hot issues right now. How do LCDs compare in the energy efficiency category?

• As energy prices soar, consumers are watching their power bills. When considering a new TV, LCD presents a more energy-efficient option than CRT or plasma, helping reduce damage to the wallet and the environment. Since the electricity costs of a TV over its lifetime can approach the cost of the TV itself, considering low-power options makes a lot of sense.
  
• New technologies, such as advanced LED backlighting, will soon lower LCD power consumption by 20-30%.
  
• In a recent series of tests reported by CNET Labs, LCD TVs were found to consume the lowest wattage per square inch. Taking the averages from the tests, LCDs consumed .29 watt per square inch; plasmas consumed 0.34 watt per square inch, and CRT also consumed .34 watt per square inch. The lab noted that some LCD TVs can consume as low as .11 watt per inch.
  
• Some LCDs have backlights that you can turn down to consume less power or produce a dimmer image.
  

10) LED-backlit LCD screens are supposed to be a highly efficient means of backlighting that provides a brighter screen than traditional CCFL backlighting. Is this true and will all LCD TVs convert to LED backlighting in the future?

• After liquid crystal technology itself, backlighting is the most important technology affecting the quality of the image displayed. Increasingly, light-emitting diodes (LEDs) are becoming more common as the backlighting technology of choice in many LCDs. LED-backlighting provides higher color saturation than the traditional means of LCD-backlighting which employs CCFL or cold cathode fluorescent lamps. CCFL generally provides 70 percent of the NTSC standard for the color gamut level, while LED backlighting provides up to 100 percent of the NTSC standard when using RGB LED backlighting.
  
• While current LED backlighting technology makes it a more expensive proposition than CCFL, Samsung is leading the charge to develop a more cost-effective LED market solution.
  

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