TV Buying Guide Part 2: LCD vs OLED Technologies

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So, you’re in the market for a brand spanking new television set and have already looked up the first part of our TV guide. It’s safe to say that by now you have a fair idea as to why it’s pointless to judge a TV by what you see in the showroom and that your helpful neighbourhood TV salesman isn’t exactly looking out for the best of your interests. We also learned how to go about the TV buying process by demystifying some of the most common TV jargon and how it affects your TV viewing experience and therefore your buying choice as well. Now that we have some idea as to what to look for in a TV, let’s figure out what makes the two dominant TV technologies tick and which one suits your budget and viewing needs.

OLEDs Trump LCDs

Let’s get right down to the brass tacks. The only two commercial TV technologies you should be concerned about are LCD and OLED. If you’re wondering which one of these is better, the answer without much ado is OLED. There’s no sugar coating this one to be honest. We aren’t even looking at some special use case where the LCD makes sense over the OLED. No sir, OLED TVs are categorically better than their LCD counterparts in every conceivable aspect except price, and display luminance if you want to pick some nits.

Now, before you hit the comments section to complain how this comparison is unfair because LED TVs are different and vastly superior to LCD TVs, save your keystrokes because LED displays are nothing but LCD displays that use LEDs for backlighting instead of CCFL tubes. In fact, pretty much all the LCD TVs sold now are LED-backlit LCD TVs. Since that’s too many words, these displays are colloquially referred to as LED TVs.

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What Makes OLEDs Better?

So what exactly makes LCD displays so inherently inferior to OLEDs, or plasma panels, or CRTs for that matter? That’s primarily because OLEDs, plasmas, and CRTs are emissive displays, whereas LCDs are transmissive. In layman’s terms, a emissive display essentially has the individual pixels emitting light. Transmissive displays such as LCDs depend on liquid crystals to block and bend light routed from a backlight to reproduce an image. Light is hard to block and such displays simply cannot do so entirely, leading to light leakage and poorer blacks.

These displays also reproduce colour by changing the physical orientation of liquid crystals to bend light, which in turn is passed through several colour and polarising filters to achieve the desired effect. This method isn’t anywhere near as accurate enough to faithfully reproduce colours. Liquid crystals themselves can’t change states quick enough to deliver fast enough response times. In effect, this leads to poor colours and an unsettling level of motion blur.

Furthermore, the bending of light and its passage through myriad arrays of colour and polarisation filters makes the entire display susceptible to parallax issues, which leads to colour shift and restricted viewing angles. The backlight itself tends to be impure and isn’t entirely comprised of red, green, and blue hues. The pink, orange, and yellow hues contained within the LED backlight further introduces inaccuracies in the colour reproduction of an LCD panel. OLEDs on the other hand face none of these issues.

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Better Colour Reproduction

For starters, OLED displays boast of significantly better colour reproduction compared to their LCD counterparts. That’s because while LCDs employ liquid-crystal filters to block and bend light to create different colours, OLEDs reproduce accurate colours by exciting the phosphors to emit light of desired colour. This method is similar to that employed by plasma as well as CRT TVs, which is the most uncomplicated means to generate colour. That also means OLEDs don’t have to deal with quality sapping colour and polarisation filters or the issues arising from using liquid crystal to bend light. That’s basically why OLEDs are better at producing superior contrast levels and authentic colours with rich saturation.

Better Contrast and Black Detail

OLEDs are emissive displays where the individual pixels themselves generate light, so they don’t need backlighting. This not only makes these panels thin, but it allows them to switch individual pixels off completely. That means no light leakage and the ability to reproduce pure blacks and render enhanced greyscale detail. LCD’s try to get around this problem with locally-dimmed panels that switch off some LED diodes, but this only ends up introducing an annoying halo effect in the darker scenes. Moreover, deeper blacks also translate into better contrast levels as well.

No Backlight Bleed

If you have owned an LCD television, you most certainly aren’t a stranger to the phenomenon known as backlight bleed. It manifests itself through very conspicuous bright spots visible across the panel in random locations. It can be caused by myriad factors such as the backlight escaping from the display chassis or just improper or poorly designed diffusion panel. Whatever the cause, this gremlin has an adverse effect in colour reproduction as well as the overall picture uniformity. OLED panels, naturally, aren’t susceptible to this issue since they don’t need a backlight at all.

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Faster Response Time

Pixel response time is the measure of time required by the displays individual pixels to transition from grey to black and white to black states. OLEDs are approximately ten times as fast as conventional LCD displays when it comes to pixel response times. LCDs suffer from slow response times primarily because they use electrical stimulation to bring about changes in the state of liquid crystals to create the desire transition of pixels. The pixels in an LCD panel are refresh much slower because the liquid crystals can’t change states fast enough. This is manifested as noticeable blurring apparent in fast moving images. This is a grave problem if you play a lot of videogames or watch a lot of action movies or sports. LCDs attempt to get around this issue through smart electronic solutions such as frame interpolation, pixel overdrive, backlight scanning, and higher refresh rates. However, the same technology works with OLEDs to deliver even more enhanced blur reduction.

The LCD Strikes Back

So far we have witnessed how LCDs are inferior and are trumped by OLED TVs in all crucial picture quality parameters. But then why isn’t LCD technology dead and relegated to annals of history as a complete and utter failure? Why isn’t everyone buying OLED TVs instead? Well, that’s because OLEDs aren’t affordable. They start from 55-inches and onwards and cost a minimum of Rs 2 lakhs at the moment. Needless to say, LCDs are going to be around for quite some time then.

However, the smart engineers behind LCD technology have hit back with the new Quantum Dot technology. An improvement over and compatible with existing LCD technology, Quantum Dot enhanced TVs aim to compete with OLED TVs while staying within the reach of the common man by positioning themselves within the huge price gap separating tradition LCD and OLED televisions. In the Part 3 of our TV Buying Guide, we will cover what makes Quantum Dot TVs tick and if they can challenge the OLEDs.


Content peddler by day and avid gamer by night, Nachiket has been obsessed with computers since the days of the 8086. He has worked with some of the reknowned tech publications and media houses like UTV, Network 18, Digit, Chip, TechTree, Tech2, International Business Times Australia, and DNA. His free time is meant for tinkering with hobby grade R/C, or just sharpening his knives. He also has a kitten named Nigel and is ready to give up his aquariums for him.