The Difference Between 120Hz & 240Hz LED TVsby Andy Josiah ; Updated September 15, 2017
The 120 Hz and the 240 Hz frequencies are refresh rates for high-definition televisions, which include LED TVs. A refresh rate is defined as the speed at which the TV can switch from one picture to the next. In this sense, 240 Hz is a faster rate than 120 Hz. However, it is precisely because of its slower speed that the 120 Hz is considered a better rate for a natural TV display.
Refresh rates rose in importance when early LED TVs – liquid-crystal display televisions that use light-emitting diodes for their backlight – suffered from motion blur. This is when the TV produces a streaking effect upon failing to keep up with fast-motion events. Although 60 Hz became the standard refresh rate by 2007, it was surpassed by 120 Hz in 2009. As of 2011, 240 Hz is one of the faster refresh rates that some TV manufacturers use.
Due to its faster speed, the 240 Hz rate is designed to reduce motion blur better than the 120 Hz rate, thus producing a smoother picture. The numerical digits represent the number of times per second that the LED TV can change its pictures. Thus, a 240 Hz LED TV can do so 240 times – twice as much as a 120 Hz LED TV.
Some LED TV manufacturers combine their refresh rates with video processing technology to combat anti-judder. This is the vibrating or trembling effect that occurs with the display during conversion of film content to video. A faster refresh rate also means the reduced likeliness of judder, thus making a 240 Hz LED TV better than a 120 Hz LED TV in that regard.
Too Smooth, Too Stable
The downside of a faster refresh rate is the tendency to smoothen and stabilize a LED TV display to the extent that the images and motion come off as less realistic or natural. This is because the refresh rate by far outstrips the speed of source material. This is especially true for film content, which is only processed at a range between 24 and 60 frames per second. Thus, a 240 Hz LED TV might produce a more artificial display of images than 120 Hz.