QLED, OLED, LCD Differences
Buying a new TV ain’t what it used to be—there are a lot more choices and features to think about than yesteryear, when the only decision you needed to make was screen size. Among the most common questions I’m asked these days is, “Should I get an LCD or plasma flat-panel TV?” If you want the quick answer, jump to the end of this article. But if you want to understand the answer, read on.
Misconceptions
LCD is clearly the more popular choice these days, outselling plasmas by a goodly margin. This is due to how TVs are displayed in stores and some misconceptions about plasma longevity and “burn-in.”
In retail stores, TVs are typically displayed in showrooms with lots of bright lights, and LCDs can pump out more light than plasmas can, which makes them look brighter and more attractive in that environment. But your living room or home theater is nothing like a retail showroom, so this apparent advantage is somewhat deceiving.
Many people are concerned about the longevity of plasmas, having heard rumors that the gas within the screen must be “recharged” periodically. This is completely false—plasma TVs have never required “recharging.” Today’s plasmas and LCDs have about the same expected lifespan—around 60,000 hours, which translates to over 20 years of watching TV eight hours a day, seven days a week.
Then there’s the issue of plasma “burn-in,” which causes ghostly images to remain on the screen after a static picture has been displayed for some period of time. This used to be a problem with early generations of plasmas, but it is almost no concern today. Yes, static images can be retained after a time, especially when the set is new, but it is rarely permanent, and it can be combated using one of several different techniques that most plasma TVs provide.
One thing to be aware of is the set’s power consumption. Plasmas tend to consume more power than comparably sized LCDs, though manufacturers are narrowing that gap in modern designs. Interestingly, plasmas draw more or less power depending on the overall brightness of the image at any given moment.
By contrast, LCDs draw relatively constant power. And if you decrease the brightness of an LCD’s backlight—which is usually advisable in a dark room—you can save even more power.
So, what are the real issues you need to consider in making this important decision? Ask yourself the following questions:
What will I be watching mostly?
If you’re a serious movie watcher, I generally recommend plasma for its lower black level and higher contrast, which makes the picture “pop” more than most LCDs illuminated by a CCFL (cold-cathode fluorescent) backlight. However, more and more LCD TVs today use LEDs (light-emitting diodes) instead of CCFLs for the light source, and these sets can achieve very deep blacks—with a few caveats.
There are two types of LED-illuminated LCD TVs—backlit and edgelit. As these terms imply, LED-backlit sets have LEDs in an array behind the LCD panel itself, while LED-edgelit models have LEDs at the edges of the screen, and their light is diffused and directed through the LCD panel using special optical materials.
Virtually all LED-backlit models provide a feature called local dimming, which brightens the LEDs behind bright areas of the image and dims the ones behind dark areas, essentially forming a very low-resolution, black-and-white version of the image as shown above. This greatly increases the perceived contrast and depth of blacks, but small, bright objects on a dark background—such as stars in outer space—can be surrounded by halos, because the size of the independently dimmable LED “zones” is often much larger than the size of the bright objects.
Just like CCFL sets, LED-edgelit LCD TVs such as the Sony NX810 seen here can brighten and darken the entire screen dynamically, resulting in better blacks and contrast overall. In fact, LEDs can be dimmed farther than CCFLs, and they can be turned off completely if the entire image is solid black, such as the interstitial black screens between the opening shots in Cars or the title screens in Master and Commander
. However, you can often see this process in action, which can be distracting.
Another problem with virtually all LED-edgelit LCDs is uneven lighting in dark scenes, which is referred to as poor screen uniformity. Some portions of the screen—especially the corners and sides where the LEDs are located—look lighter than other portions when displaying dark scenes. This is also evident in black letterbox bars when watching widescreen movies.
If you plan to play lots of video games on your new flat panel, LCD is probably the way to go. Video games have many static elements (score boxes, unmoving scenes, etc.) that can leave ghost images on plasmas, especially when they’re new. The same goes for some TV shows, especially news and business channels with a ticker running across the bottom of the screen.
The problem is compounded if you watch a lot of 4:3 TV or 2.35:1 movies—an outline of the 4:3 or 2.35:1 window can appear on the screen after a while. Many plasmas provide a “wipe” function that floods the screen with white to exercise these ghosts, but the longer they remain on the screen, the harder it is to completely erase them. As I mentioned earlier, new models are much better about this, but it is a concern that LCDs do not share for the most part, though some can exhibit slight image retention.
If you tend to play games and/or watch sports or other fast-motion material and you decide on an LCD, get one that refreshes the screen 120 or 240 times per second (120Hz or 240Hz) instead of the conventional 60Hz, which suffers from “motion blur.” When this higher refresh rate is combined with frame interpolation—new frames are generated by the TV to fill in the gaps between actual frames, as shown above—they can significantly sharpen onscreen motion. (Frame interpolation is also called motion estimation/motion compensation, or MEMC.) On the downside, it can also introduce an artifact called the “soap-opera effect,” which makes movies look like they were shot on video. Many people hate the way this looks, but I can easily tolerate it in favor of less motion blur.
Just to be perfectly clear, LED backlighting with local dimming, which is used in the SIM2 HDR47 seen here, and high refresh rates with frame interpolation are designed to address problems that plasmas do not suffer from in the first place. On the other hand, LCD TVs exhibit much less image retention than plasmas.
In what environment will I be watching?
If you have good control of ambient light in the room, or you watch mostly at night and can dim or turn off the room lights, either type of flat panel will work just fine, and as I said earlier, I prefer the look of plasma in this case. However, if you watch during the day without good black-out shades or you need to leave the lights on, LCD is often the better choice.
Plasmas have a shiny, reflective screen, while many LCDs have a matte screen that does not reflect room light nearly as much. (Samsung LCDs are one exception with shiny screens.) So if you watch the TV with lots of room light, you can often see yourself and other objects reflected in a plasma screen, especially during dark scenes. This problem is even worse during the day if there’s a window or glass door directly opposite the screen.
Will it normally be a large or small group watching?
If you often host a large gathering around the electronic hearth, or you often watch from off-center—say, from the kitchen while cooking—plasma is a better bet with its much wider viewing angle. If you mostly fly solo or cozy up to your partner for an evening’s video entertainment directly in front of the TV, either technology will work fine.
In the graphic above, the upper two images show a plasma directly on axis and about 45 degrees off axis; the lower two images show the same views with an LCD TV. Notice that the colors tend to wash out more on the LCD when viewed off axis, and the difference between white and black in the bottom row of squares is diminished, leading to less contrast in the picture.
How much can I afford to spend?
Inch for inch, LCDs have traditionally been more expensive than plasmas, and this is often still true—at least slightly—for screen sizes of 50 inches or more. And LED-backlit LCDs are definitely more expensive than similarly sized plasmas and LED-edgelit LCDs. Of course, features also play an important role: 3D capabilities, online apps, more inputs, even cabinetry all affect the price of both types of displays.
Speaking of cabinetry, all types of flat panels are getting mighty skinny these days; thinnest of all are LED-edgelit LCDs, such as the Vizio Blade seen edge-on in the photo above. If you intend to mount your new flat panel on the wall, pay attention to the cable connections—super-thin panels often have connections oriented sideways, which might require cables with angled connectors. And if the sideways connectors are on the edge of the panel, it might be difficult to hide the cables.
You can spend as little as $400 or even less for a good 32-inch LCD up to $500,000 for Panasonic’s 152-inch plasma. (Sizewise, plasmas start at 42 inches and go up from there, so if you want something smaller, it’ll be an LCD.) Expect to pay somewhere in the neighborhood of $1000 to $2000 for a good flat panel in the 50-inch size range.
Cheetsheet
The following table summarizes the pros and cons of LCD and plasma. Which technology has pros that are important to you and cons you can live with? That’s the answer to the question “LCD or plasma?” for you.
| Technology | Pros | Cons |
| Plasma | – Lower black level, higher contrast than CCFL LCD – Best motion detail – Widest viewing angle – Large sizes generally less expensive than comparable CCFL & LED-edgelit LCD, way less than LED-backlit LCD |
– Shiny, reflective screen – Potential for image retention – Draws more power on average than comparable LCD – Heavier than LCD of equal size |
| LCD (CCFL backlight) | – Brighter, better room-light tolerance – Most have non-reflective matte screen – Little chance of image retention – Draws less power on average than comparable plasma – Weighs less than plasma of equal size |
– Higher black level, lower contrast than plasma – Motion blur in 60Hz models – Narrow viewing angle – Large sizes slightly more expensive than comparable plasma |
| LCD (LED backlight w/local dimming) | – Generally lowest black level, highest contrast – Brighter, better room-light tolerance – Most have non-reflective matte screen – Little chance of image retention – Frame interpolation in 120 and 240Hz models can decrease motion blur – Draws less power on average than comparable plasma – Weighs less than plasma of equal size |
– Most expensive type of flat panel – Local dimming can cause halo effect around bright objects on dark background – Frame interpolation in 120 and 240Hz models can cause “soap-opera effect” – Narrow viewing angle |
| LCD (LED edgelight) | – Brighter, better room-light tolerance – Most have non-reflective matte screen – Little chance of image retention – Frame interpolation in 120 and 240Hz models can decrease motion blur – Draws less power on average than comparable plasma – Thinnest type of flat panel – Weighs less than plasma of equal size |
– Lighting in dark scenes and letterbox bars usually uneven – Frame interpolation in 120 and 240Hz models can cause “soap-opera effect” – Narrow viewing angle – Large sizes slightly more expensive than comparable plasma |
If you don’t understand the pros and cons listed here or why they are good or bad, call Lanza Home Theater and Security. Then, lets go forth and find the flat panel of your dreams!
Source: https://www.hometheater.com/content/should-you-get-lcd-or-plasma-flat-panel-page-2