Different physics, different pictures
What is the difference between plasma and LCD?
Ah, a really great and perhaps the HD question I am asked most frequently. Let’s look at the physical differences first. We’ll discuss practical differences afterwards.
On a physical level, a plasma screen generates light by exciting gas inside a tiny capsule which in turn excites phosphorus that emits light that you see a pixel. Filters are used to generate colored light.
Meanwhile, LCD (liquid crystal display) works by running a charge into a tiny capsule of material that is liquid in one state and solid in another. As the electricity is increased, the crystals “twist” to block the light source (or untwist to allow the light to shine through). When fully blocked, the liquid crystal filled capsule shows up as a black pixel. When it is fully unblocked, it shows up as a white pixel. Filters are applied to give it color.
The practical differences are numerous:
- Plasma
is ideal for larger screens, such as 50 inches and up because its pixels tend to be larger.
- LCD has finer pixels and so – for the HD purist – it is a better choice for a sharper picture. LCD is the preferred choice below 50 inches, although it’s pushing the size-boundary these days.
- Plasma
display. So plasma has richer blacks and more vibrant colors. The reason: A black pixel on a plasma is a pixel turned off. A black pixel on LCD is a light source that’s blocked by twisted crystals. But there is still some light leakage.
- LCD is up to 30-per-cent more power-efficient over plasma. A choice for people who like to buy with energy conservation in mind.
- LCD display has a longer lifespan, typically 60,000 hours. Plasma screens can have lifespans that vary from 30,000 to 60,000 hours.
- LCD can also be more competitively priced than plasma.
But in the end, I invite you to stand in front of both screens. Sometimes it comes down to taste.