When shopping for a new television set, buyers often have to choose between an LED or LCD TV. Although there are no obvious differences between the two options at first glance, it pays to understand the details of these technologies.
LCD TVs: How Do They Work?
LCD was at the forefront of the flat screen television trend, although the technology has been used for a while in calculators and digital watches. LCD technology uses liquid crystal display panels, which consist of liquid crystals sandwiched between two sheets of polarising filters, to control how light is displayed on the screen. Since these crystals don't produce lights of their own, an LCD TV uses cold cathode fluorescent lamps (CCFL) as backlights.
The lights emitted pass through the LCD panel, and the polarising filters of the panel serve as a shutter which either allows light to shine through or blocks light to form an image on the screen. Each pixel consist of three crystals (red, blue, and green) that produce thousands of colours on the screen. LCD TVs use thin film transistors (TFT) to turn LCD pixels on or off.
LED TVs: How Do They Work?
LED is a misnomer. The more accurate term is LED-backlit LCD display. LED TVs are really a subset of the LCD technology and use the same type of liquid crystals to form the display panels. The only difference between the two is that LED uses light emitting diodes as backlights instead of LCD's CCFL. LED TVs are currently available in two types:
Sometimes known as direct-lit or full-array backlighting, this type of LEDs has backlights on the rear part of the screen. While this allows for lighting to be more consistent, LED TVs of this type are typically bulkier.
Slim LED TVs are usually this type, since backlights are placed on the edge of the screen instead of the rear. Although this technology has improved significantly over the years, buyers have to make sure they don't get the short end of the stick, as earlier models of edge-lit LED TVs often offer inconsistent lighting.
Advantages of LED
With the emergence of LED HDTVs, LCD TVs are fast becoming a thing of the past. Below are some advantages of LED-backlit TVs over its predecessor:
- LED backlights are considerably thinner than CCFLs, and LED TVs are generally slimmer than LCD TVs. Plus, with the prevalent edge-lit technology, LEDs win the contest hands down when it comes to form.
- LED backlights consume less power than CCFLs, and LED TVs are more energy-efficient than LCD TVs.
- LED TVs offer better contrast and colour depth due to local dimming capability. The problem with CCFL backlight is that all fluorescent tubes at the back of the screen light up when the TV has to render just one white pixel on a sea of darkness. The LCD panel must block the other lights to display blackness. With this method, contrast can be compromised because the LCD panel may not entirely block out the lights. This problem is easily remedied by using LED's local dimming technique. Light emitting diodes are individually controlled, and those that are not used in specific scenes are turned off completely.
- LED backlights are capable of a wider gamut of colours, especially those sets that feature RGB-LED backlighting. This results in dynamic contrasts and better picture quality.
Why Buy LCD TV if LED TVs Are Great?
While LED TVs supersede LCD TVs in terms of style, power consumption, and picture quality, price is still the LCD TV's biggest advantage. Consumers who want the features that an LED TV offers are expected to pay a premium for it.
Consumers are faced with so many choices when they shop for a new television set. Buyers can browse online stores to check out all the options available. Those who want TVs that are slim, energy-efficient, easy to mount, and offer a better picture display would do well to choose an LED TV. LCD TVs may be the outdated choice of the two, but for those buyers who have a limited budget, this type of flat screen will do.