If you're looking to buy a new TV this year, you have two main options: LED and OLED. While their names suggest they're similar, in many ways they're actually quite different. The broad term "LED" also covers QLED, QNED, ULED and even mini-LED, which are all fundamentally similar to each other. OLED and QD-OLED are closely related.
Broadly speaking, OLED is a newer technology that is usually more expensive, but it typically produces better image quality. That's why our best TV list has had an OLED TV at the top for years. That's not to say you shouldn't consider an LED TV. They have their own strengths, and they're improving every year, and they could be a better option in some homes.
What's an LED?
The evolution of LEDs getting smaller and smaller. The top left is the most recent, getting larger/older in a clockwise direction. Geoffrey Morrison/CNET
LED stands for light emitting diode and is a small device that, as you can guess, emits light. LED TVs have anywhere between a handful of these lights and many thousand, depending on the price and specific type of TV. The cheapest LED TVs have strips of LEDs arranged on one side of the TV, usually the bottom. The most expensive LED TVs have thousands arranged across the entire TV. Both configurations are colloquially known as the "backlight."
An LED TV is more accurately called an LED LCD, as the portion of the screen that creates the image is LCD, or liquid crystal display, a technology that first came to market over 20 years ago. Any display tech that's not OLED with a single letter in front, like QLED, ULED and so on, is LED LCDs with some additional tech thrown in. You can learn more about that in LED vs QLED.
The layers required to make an image with different TV technologies. With LCD the light and the image are created separately. With WOLED (LG's tech until recently), the "white" layer is actually blue and yellow. Color filters create red and green. Check out their latest OLED tech: How LG's 4-Stack OLED Tech Makes TVs Brighter, Better Than Ever.
With Samsung QD-OLED, only blue OLED material is used, with red and green created by quantum dots. Samsung
Meanwhile, OLED is an organic light-emitting diode, which means an LED that uses carbon as part of its design. While they create light, just like LEDs, their design means they can more easily be much, much smaller. While better LED TVs might have thousands of LEDs, OLED TVs have millions of OLEDs, one for every pixel (well, technically at least three per pixel). Because each pixel can be turned off (i.e. emit no light), OLED TVs have a better contrast ratio, as in the difference between the brightest and darkest parts of the image. LED TVs can only dim larger areas of the image behind hundreds or thousands of pixels at a time.
What's better: LED or OLED?
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