TV pixels work by combining red, green, and blue subpixels in varying intensities to create a wide range of colors that form the images you see on the screen.
Understanding TV Pixels
A pixel, short for "picture element," is the smallest controllable element of a display screen. In a color TV, each pixel is actually composed of three subpixels: red, green, and blue (RGB).
How Color is Created
- Subpixels: Each subpixel emits light of its corresponding color.
- Intensity Control: The intensity of each subpixel can be individually controlled.
- Color Mixing: By varying the intensities of the red, green, and blue subpixels, the pixel can produce a vast spectrum of colors. When all subpixels are at their maximum intensity, the pixel appears white. When all are off, it appears black.
- Human Perception: Because these subpixels are incredibly small and close together, the human eye perceives the combined light as a single color.
Example: Creating Different Colors
| Red Subpixel Intensity | Green Subpixel Intensity | Blue Subpixel Intensity | Resulting Pixel Color |
|---|---|---|---|
| High | Low | Low | Red |
| Low | High | Low | Green |
| Low | Low | High | Blue |
| High | High | Low | Yellow |
| High | Low | High | Magenta |
| Low | High | High | Cyan |
| High | High | High | White |
| Low | Low | Low | Black |
Types of TV Displays and Pixel Technology
Different TV technologies use different methods to generate the light for the subpixels:
- LCD (Liquid Crystal Display): An LCD uses a backlight to shine light through liquid crystals. These crystals can be aligned to block or allow light to pass through the red, green, and blue filters of each subpixel, controlling their intensity.
- LED (Light Emitting Diode): LED TVs are essentially LCD TVs that use LEDs for backlighting. However, some newer LED TVs, like Mini-LED TVs, use much smaller LEDs for more precise control over the backlight, resulting in improved contrast.
- OLED (Organic Light Emitting Diode): OLED TVs use organic materials that emit light when an electric current is passed through them. Because each subpixel is individually lit, OLED TVs can achieve perfect blacks by simply turning off the corresponding subpixel.
- Plasma: While largely obsolete, plasma TVs used small cells filled with gas that illuminated when electrically charged, creating the red, green, and blue light.
Resolution
The resolution of a TV (e.g., 1920x1080, 3840x2160 (4K)) indicates the number of pixels present on the screen. A higher resolution means more pixels, resulting in a sharper and more detailed image.
In summary, TV pixels work by controlling the intensity of red, green, and blue subpixels to create a wide range of colors. The technology used to generate and control this light varies depending on the type of display (LCD, LED, OLED, etc.).
