LED is a TLA. What? OK it’s a bit of a joke (TLA means “three letter acronym”). But this little quip sums up the industry’s approach to how it sometimes communicates with the consumer. It seems to think that throwing impressive looking acronyms at the consumer is a great idea.
TV technology is complex, and the manufactures make up all kinds of acronyms (usualy TLAs) to try give them a marketing difference from their competitors. Some of their technologies are really great, but sometimes you kinda wonder.
This blog doesn’t explore every technical buzz-word, but endeavors to debunk a common point of confusion.
Don’t get me wrong, acronyms have a valuable place when defining and explaining conformance to defined technology standards, and that’s fine. However, although many consumers are quite tech-savvy, a sprinkling of acronyms – designed solely to impress or befuddle the potential buyer – can lead to uncertainty and confusion.
In this article, we will try to debunk what are meant by LCD, LED and OLED.
Firstly, the meaning of these acronyms
LCD means “Liquid Crystal Display”. It’s the same base technology used in countless applications from kitchen timers, watches, laptops. A LCD (or part of it) is transparent until an electronic charge (voltage) is applied when it turns opaque/dark. The great thing about LCD is they it’s a cheap, reliable and low power technology.
LED means “Light Emitting Diode”. This is an electronic device that illuminates when powered up – again used in countless applications. LEDs have traditionally been made using very small amounts of quite nasty materials like arsenide (the common red-colour LED uses a compound called Gallium Arsenide Phosphate).
OLED means “Organic Light Emitting Diode”. These are a really terrific, advanced light source that use usually made using carbon and hydrogen. They are called “organic” because they use carbon. Because of their structure, OLEDs are very adaptable and can be made into curved shapes, or even flexible displays. Newer development include transparent displays – which could be useful to make “glass” that can display superimposed information. Imagine a pair of glasses that can show useful information to the wearer, without having the wear Google Glasses which many thought looked a little odd.
Why should you care?
An understanding of the technology means that you don’t glaze over when the TV shop salesman is liberally throwing acronyms around. So, lets explore how, for example, TVs are made, in simple terms.
LCD TVs operate by mounting an LCD in front of coloured filters which is in front of a white light (this light is a backlight that spans the rear of the LCD). Hence, as the individual pixels (a pixel being an individual “dot” of the millions in the screen) in the LCD switches to a clear state, the white light shines through the filter and out through the LCD at the front of the screen. The white light in these screens was traditionally a (fluorescent) light in the back of the TV. This is simple yet effective. In early LCD display, the LCD pixels could not switch on and off quickly enough and so we saw “ghosting” during rapid action TV like sport.
Another fundamental shortcoming of the LCD (when used in a TV) is that the LCD can never quite go completely opaque which allows some light to seep through. Hence, LCD displays could never quite achieve a total black (unlike, for example a Plasma display). These are usually the cheapest TV types.
LED TVs, in essence, is a simple upgrade to the LCD TV above where LEDs replace the fluorescent light. The same basic LCD operating method is the same. The key difference was a more consistent light spread and thinner displays. These were a little more expensive when first developed, but today you should not buy a TV that isn’t LED (or OLED – see below).
The thing to remember is that a “basic” LED TV is really an LCD TV (that is not a typo mistake) as the LEDs simply replaces the fluorescent backlight. Both the fluorescent and LEDs are situated at the edge of the screen so the only (but important) benefit is that the LED display can be thinner.
There is, however, another type of LED TV which uses an array of LEDs that spans the rear of the display – and in this case the LEDs in sections of the screen can be dimmed (in that local area) – if for example the picture has a consistent area of black in a scene. This LED display method is called “local dimming” – and its better than simple LED backlighting because it enables better blacks.
OLED TVs are very different. OLED screens are made from millions of individual LED pixels (display “dots”), thus doing away with the LCD panel and backlight. This means that these TVS can be very thin and with smaller bezels. In fact, because OLEDs are flexible, curved screens can be produced (actually quite easily). These screens are also more environmentally friendly as they use fewer hazardous metals. OLED displays are more expensive to buy, but we will see how long that situation persists as their manufacturing volume increases.
Actually, it’s my view that OLED was the key reason why Plasma are yesterday’s news. Plasma’s key benefit was “better blacks” but they used a lot of power (and boy they could get hot). Because individual OLED pixels are either illuminated or totally off, OLED TVs offer the same “blacks” at a much lower power than plasma, and are thinner lighter and cheaper. They are not, at this time, quite as bright though – but bright enough.
These are the key things to take away
- LED TVs are the same as LCD TVs, except the backlight comprises LEDs instead of fluorescent. They are not a “new generation” of technology.
- LED TVs are not the same as OLED TVs. Despite both have “LED” in the name, they are very, very different.
- Don’t let the TV salesperson get away with interchanging the words LED and OLED to bamboozle into you into buying a cheaper (LED) TV rather than having to explain OLED.
- OLEDs TVs are usually more expensive.
- OLED offers future possibilities that other technologies will struggle to deliver.
- Although the type of TV (LCD, LED, OLED) is very important, other factors like processing power, the selection of connections, and other considerations etc are also important.
If you can afford it, buy OLED. If you have to buy LED – buy LED with “local dimming”. Last choice would be “LED backlit”. Don’t bother with an LCD with florescent backlight until you just want a real cheapie TV to glance at in the garage whilst you work on the car.
Thinking about QLED versus OLED?
Read our guide here