When HDTVs first started out, refresh rates or field rates are typically rated as 50Hz (PAL) or 60Hz (NTSC). That's 25 frames per second for PAL sources, and 30 frames per second for NTSC content. Things were simple back then. But with the dawn of frame interpolation (also known as frame insertions) and backlight scanning, television makers have found a way to reduce motion blur by interpolating or adding additional frames to the TV's original frames. For instance, a 60Hz television may sport a refresh rate of 120Hz or even 240Hz using this interpolation technique. Of course, this also led rise to the infamous 'soap-opera' effect.
Now, this number can be multiplied further if backlight scanning is involved. Essentially, backlights on an LCD display are 'blinked' in between the recreated frames to create blank 'black frames' to extrapolate a TV's refresh rate specification. As such, it's not hard to find major TV brands sporting field rates close to the 1000Hz mark. For instance, Sony's MotionFlow XR and Samsung's Clear Motion Rate are known to tout figures in multiples of 240, 480, or 960; although they are careful not to associate the frequency unit (Hz) with their marketing terms. According to HD Guru, HDTV manufacturers like Sony has been replacing their televisions' true refresh rates with their proprietary Motionflow XR rating. Our advice? Ignore the fluff when shopping for a swanky new TV, and let your eyes judge for themselves.
To find out more about HD Guru's thoughts on LCD TVs and their fantastical refresh rates, click here.