Understanding TV Refresh Rates
The TV refresh rate in the industry describes the frequency at which a video screen updates per second; a high refresh rate gives you a smooth, natural-looking motion. The refresh rate originates with early film, when movie projectors ran at 24 frames per second, with shutters allowing projection of 48 frames a second (each image showed twice), or 48 hertz (Hz). Traditional, tube televisions delivered a 60 Hz or 50 Hz refresh rate.
During the early digital stages, all LCDs had issues with blurring during fast motion or when panning content, popularly known as motion blur. To resolve the issue, manufacturers created television sets that refreshed at a rate faster than 60 Hz. Today, the innovative solution uses the frame insertion technique to create additional images, which it inserts between the original images for a better viewing experience. Today, you can enjoy HD TVs with a TV refresh rate of up to 240 Hz: typically a higher refresh rate results in less motion blur.
TV marketers often use the TV refresh rate for marketing purposes to encourage consumers to upgrade. However, the refresh rate numbers have been in the market long enough that consumers often assume that a number such as 120 or 240 on the box refers to the refresh rate, and as such expect to pay more for a box with a higher number.
TV Refresh Rate in Marketing
After the introduction of HD TV sets, manufacturers got into a "refresh rate" race of sorts, ramping up refresh rates in multiples of 60, 120 and 240 Hz. In the marketing craze, some marketers made dubious claims of a refresh rate of up to 600 Hz, feeding into the assumption that the higher the number, the better the product.
In the post-HD 4K era, TV sets are still at a 240 Hz refresh rate. However, most of the TVs in the market, including the 4K TVs (with price tags of $1,000-plus) feature a refresh rate of 120 Hz at best. The less expensive versions are at 60 Hz, with the more expensive versions offering a higher TV refresh rate.
Most of the refresh rate references by TV manufacturers and marketers exist to convince you to get a new TV set, with different brands coming up with different terms to refer to their model's TV refresh rate and individual motion blur solution. The "refresh rates" you see on marketing campaigns from different brands are not complete fabrications. Each company uses a simple, though dubious, method to determine and make refresh rate claims. In order to boost their numbers, different brands use the flashing backlight and video processing to determine the "refresh rate." All LCD panels feature a backlight that helps in image creation. The backlight flashes fast without creating flicker, playing every image twice and significantly reducing motion blur. Video processing, on the other hand, offers "motion smoothing" for a better viewing experience.
Some of the common ‘refresh rate’ terms you will see on your favorite brands include:
LG – TruMotion
LG refers to its refresh rate as TruMotion. LG advertises TruMotion as the better option for fast-action video, with 120, 240 and 480 Hz options available on some LCD TVs. In the models available in the market, only one has a 480 Hz TruMotion. The other models are either TruMotion 120 or 240 Hz.
Panasonic – Backlight Scanning
Panasonic is open about its backlight scanning, with statements from the manufacturer claiming that the Backlight Scanning technology minimizes flicker, even in high-speed action images to give smooth viewing. The 120 Hz/240 Backlight blinking technology also promises to improve clarity, contrast, and sharpness, with virtually no image blur.
Samsung - CMR
Samsung takes a more creative marketing approach; instead of using the ‘480 Hz’ claim, they have CRM (Clear Motion Rate). The CMR takes into consideration the three basic factors that influence motion clarity namely: image processor speed, panel refresh rate and backlight technology. This means that a TV with a 240 CMR may have a 120 HZ panel, a scanning backlight and an average processor. Therefore, there is no guarantee that a TV set with a CMR of 240 could come with a 240 Hz panel.
Sharp – AquoMotion
Sharp is quite honest with its specs specification; however, their backlight scanning technology multiplies the refresh rate to give you smooth images during fast-moving action and sports. For example, AquoMotion 960 quadruples the refresh rate while the AquoMotion 480 backlight scanning technology doubles the refresh rate, which means your screen features a 240 Hz screen in both cases.
Sony – Motion Flow
Sony claims to improve picture clarity during fast action by taking the image viewing experience beyond the refresh rates by quadrupling the motion effect so that you can enjoy the action as if you were present.
Toshiba – ClearScan and ClearFrame
Toshiba’s marketing messages cover very little detail about is ClearFrame and ClearScan technology. Both the ClearFrame and ClearScan technologies improve clarity significantly, without affecting the flicker and the brightness of the image. TV lovers who prefer a film look can choose the 5:5 pull down option available with the ClearScan 240 Hz.
Vizio – SPS
Vizio’s SPS (Scenes Per Second) offers 120 Hz technology together with scanning backlight for high quality detail. This essentially means that the "240 Hz SPS" refers to a 120 Hz TV with a scanning backlight.
A plasma TV does not feature a TV refresh rate that compares equally with an LCD. For example, you will see claims of 600 Hz; however, they do not compare directly to the 120 and 240 Hz refresh rates mentioned above. Producing LCDs with a higher TV refresh rate is significantly more expensive, forcing manufacturers to get creative about including higher numbers in their marketing.
OLED TVs have a 120Hz refresh rate but since OLEDs are solid state emissive devices, the have very fast response times, sometimes 10 times faster than LCDs. As a result, there is virtually no motion lag or trailer effect and no visible Motion Blur.
You will rarely find the actual TV refresh rate mentioned on your TV set. However, most online reviews and some listings will include the actual refresh rate of every panel available.
While buying your next TV set, do not go by the manufacturer’s refresh rate claim. While the different interpretations of the refresh rate can help resolve motion blur, it does not mean the same as increasing the refresh rate. Make an informed decision by going through available resources to find out the true refresh rate and other technologies that help improve overall picture quality.