Plasma vs LCD vs LED
Wondering about the differences between Plasma vs LCD vs LED!
Have you been thinking lately of buying a High Definition Television (HDTV), and not sure of today’s technology?
You have reached the ideal site Plasma vs LCD vs LED.
Here I will take the technology jargon and break it down into simple to understand language.
Plasma TV
A Plasma TV is called plasma because the technology uses very small cells (also known as pixels) containing electrically charged ionized gases (xenon and neon). You can find these cells or pixels along the length and breadth of the screen. There are thousands upon thousands of these tiny cells, behind the screen. Each cell is made up of three fluorescent lights, red, blue and green. Plasma forms the central element of these fluorescent lights. Based on the video signals coming into the Plasma TV, the individual cells or pixels will glow in varying intensity of red, blue and green color, forming the images on the screen.
Plasma displays are generally bright, and have a wide color range. The black color in plasma has low luminance. This means that blacks are shown as real black on plasma, and greyer on LCD TVs. You can find screen sizes from 30 inches and upwards. Power consumption is more in plasma vs LCD vs LED. The life expectancy for latest generation plasma TVs is 100,000 hours of display time at 8 to 10 hours per day.
Plasma screens are made up of glass and as a result reflect more light than the materials used to make an LCD or LED screen. So you have to make sure that your TV room has controlled light. Even though the latest models of Plasma screens have antiglare material, it’s suggested that you consider the fact that streams of light falling on plasma screen could cause glare.
LCD TV
Liquid Crystal Display (LCD) is probably found in some of the items you use daily. It’s commonly found in digital wristwatch, laptops, MP3 players, and some kitchen appliances like microwave, some model of slow cookers and so on.
Haven’t you heard about the three states of matter? Matter could be Solid, Liquid or Gaseous. Solids are solid because the molecules that make them up stay the way they are, maintaining their orientation in respect to one another. Whereas the molecules in liquids keeps changing their orientation and move around within the liquid. But in some substances the molecules exists in both liquid and solid state. When it’s in this state, the molecule attempts to maintain its orientation like in solids but at the same time moves around within the liquid to different positions, like in liquids. That’s how liquid crystal got its name. In fact, liquid crystals are more biased towards a liquid state than solid.
The function of liquid crystal is based on the interacting properties of the liquid crystal itself and light. Liquid crystal does not have it’s own light. There is a light source behind the screen. This light source is a series of Cold Cathode Fluorescent Lamps (CCFLs). Liquid crystals are broken down into tiny cells (pixels), which forms the very smallest unit of screen resolution. If you are to open and remove the front panel, you could see the pixels along the length and breadth of the screen.
The liquid crystals are placed in between two electrodes among other circuitry and light filters. These circuitry and filters selectively allow the passage of light, which passes through multitude of individual LCD shutters. These shutters form the colored filters, and allow only the red, green and blue light to pass through. A shutter and filter pair forms an individual sub-pixel and these sub-pixels compound together to form the image on screen.
There are different types of technologies used to manufacture LCD panels (display) as compared to plasma or LED. I will briefly touch on those here.
Panel Technology
▪ S-IPS/H-IPS [In Plane Switching] panels are considered the best among all LCD panel type, but they are very expensive and very few are made. High end, expensive.
▪ S-PVA/MVA [Vertical Alignment] panels gives better color reproduction and viewing angles than TN panels; response time is slightly slower than TN or S-IPS; best contrast ratios. Mid range; fair price compared to plasma or LED.
▪ TN [Twisted Nematic] panels are the most widely used ones for LCD TVs. TN panels are very cheap and have the quickest response times, but it suffers from inferior color reproduction, contrast ratios and viewing angles. Low end, inexpensive compared to plasma or LED.
LED TV
An LED TV is an LCD TV that uses LED [Light Emitting Diode] backlighting instead of cold cathode fluorescent lamps. In other words, the light source for LED TV comes from light emitting diodes.
Since LED lamps are really small, there are various advantages. One being a real slim or thin display panel and the other being low power consumption among many other benefits.
Essentially, there are three typical ways these LEDs are placed inside the TV, which makes them different from plasma and LCD. Edge LEDs; Dynamic RGB LEDs and a Full array of LEDs.
Edge-Lit LEDs
In this layout, white edge-LEDs are laid around the edge of the TV screen and a special light diffusion panel [light guides] is used to spread light uniformly behind the screen. This allows the engineers to remove extra layer of LEDs and just have LEDs on the four sides of the TV screen. This makes Edge-lit LED TVs to be the thinnest and is the most commonly available ones in market today, compared to plasma and LCD.
Full-Array LEDs Without Local Dimming
A full array of LEDs is arranged behind the screen, across the back of the entire panel, just like a CCFL backlight. This makes the screen thicker. Not so widely used.
Full-Array LEDs With Local Dimming [Dynamic RGB]
In this method, LEDs are positioned right behind the entire screen, just like full-array, but individual sections of LEDs can be dimmed or brightened independently, while other sections of LEDs gets darker or brighter. This helps to reduce the light that leaks into the darkened areas. This makes black appear blacker and realistic. As black levels are very important for contrast ratio, darker the blacks, sharper the picture. The disadvantage of local dimming is that it creates an effect called “blooming”, where brighter areas seep into the darkened areas and reduce the black levels. But blooming varies from model to model.
| Plasma: Advantages | Plasma: Disadvantages |
|---|---|
| Great black levels with excellent contrast ratio | A slim chance of screen-burn but with technological advancements, the chances are very less |
| High refresh rates; fast response time with superior performance | power consumption is more than LCD or LED |
| Wide viewing angle | Can cause buzzing noise when used at very high altitudes |
| Great for home theatre setup |
| LCD Advantages | LCD Disadvantages |
|---|---|
| High resolution compared to equal sized plasma | Picture quality degrades when viewed from an angle |
| Power consumption is less than plasma | Response time is low for fast moving images |
| No screen-burn | Motion blur |
| Less heat generated than plasma | Chances of dead or stuck pixels at manufacturing or through usage |
| Lighter than plasma | Black levels not as good as plasma |
| No screen reflections | |
| Cheap |
| LED Advantages | LED Disadvantages |
|---|---|
| Deep Black levels and higher brightness (comparable to plasma) | Expensive |
| Rich colours | Picture quality degrades when viewed from an angle |
| Crisp picture quality than LCD | |
| No screen-burn | |
| Power consumption lower than plasma and LCD | |
| Heat generated is very lesser than plasma & LCD | |
| With Edge-Lit LED configuration, display panel can be very slim | |
| LED uses no mercury. Mercury is an environment pollutant |
I hope this article helped you understand the difference between plasma vs LCD vs LED and given you a better understanding of the technology behind plasma, LCD or LED.
