How It Works
How a Light Emitting Diode works:
Light emitting diodes, commonly called LEDs, are real unsung heroes in the electronics world. They do dozens of different jobs and are found in all kinds of devices. Among other things, they form numbers on digital clocks, transmit information from remote controls, light up watches and tell you when your appliances are turned on. Collected together, they can form images on a jumbo television screen or illuminate a traffic light.
Basically, LEDs are just tiny light bulbs that fit easily into an electrical circuit. But unlike ordinary incandescent bulbs, they don't have a filament that will burn out, and they don't get especially hot. They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor. The lifespan of an LED surpasses the short life of an incandescent bulb by thousands of hours. |
How LEDs work in Televisions (3 types)
![Picture](/uploads/4/7/1/5/47157043/7555000_orig.png)
Full array LED backlight
This method is considered the best LED backlight type, but can only be found on a limited number of models.
In a full array LED screen, the LEDs are distributed evenly behind the entire screen. This produces a more uniform backlight and provides a more effective use of local dimming, where it can change the luminosity of only a specific part of the screen.
In some TVs, like Sony's XBR line, they use colored LEDs instead of white ones. Technically, this can create an even greater color range gamut by matching the backlight color with the picture. In practice though, you will not really see the difference.
This method is considered the best LED backlight type, but can only be found on a limited number of models.
In a full array LED screen, the LEDs are distributed evenly behind the entire screen. This produces a more uniform backlight and provides a more effective use of local dimming, where it can change the luminosity of only a specific part of the screen.
In some TVs, like Sony's XBR line, they use colored LEDs instead of white ones. Technically, this can create an even greater color range gamut by matching the backlight color with the picture. In practice though, you will not really see the difference.
![Picture](/uploads/4/7/1/5/47157043/3430877.png?250)
Edge-lit LED backlight
This is the most common method for LED TVs.
With an edge lit LED screen, the LEDs are placed at the peripheral of the screen. Depending on the television, it can be all around the screen or only on the sides or the bottom. This allows the screen to be very thin.
However, it can cause some spots on the screen to be brighter than others, like the edges. This problem is called flashlighting or clouding. It can be seen when watching a dark scene in a dark environment.
This is the most common method for LED TVs.
With an edge lit LED screen, the LEDs are placed at the peripheral of the screen. Depending on the television, it can be all around the screen or only on the sides or the bottom. This allows the screen to be very thin.
However, it can cause some spots on the screen to be brighter than others, like the edges. This problem is called flashlighting or clouding. It can be seen when watching a dark scene in a dark environment.
![Picture](/uploads/4/7/1/5/47157043/1728924_orig.png)
Direct lit LED backlight
This is how the lower-end LED TVs are constructed.
Similarly to the full array method, the LEDs are directly behind the screen. However, there are very few of them and they cannot be controlled separately to match the luminosity of the picture.
These TVs are not very thin because of the space required behind the screen to add the LEDs and to diffuse the light over a big area.
This is how the lower-end LED TVs are constructed.
Similarly to the full array method, the LEDs are directly behind the screen. However, there are very few of them and they cannot be controlled separately to match the luminosity of the picture.
These TVs are not very thin because of the space required behind the screen to add the LEDs and to diffuse the light over a big area.