Which display type operates fully on DC power and is known for being more energy-efficient?

LED displays, which refer to Light Emitting Diode technology, operate fully on direct current (DC) power. This characteristic contributes to their increased energy efficiency compared to other display types. The technology uses an array of LEDs to emit light and create images, which allows for lower energy consumption. This efficiency is particularly noticeable in backlit applications, where LEDs can be dimmed more effectively, leading to less power usage when displaying darker images.

LED displays are also known for their ability to produce bright images with vibrant colors while maintaining a lower heat output compared to other types of displays. This combination of low power consumption and heat generation not only conserves energy but also potentially extends the lifespan of the display.

In contrast, LCDs still typically require a backlight that may not be as efficient as LEDs, while TN and IPS panels are variations of LCD technology, relying on the same principles but using different methods to manipulate light. As such, LED technology stands out in terms of energy efficiency and DC operation, making it the correct choice among the display types listed.