The PAL television standard prescribes a frame rate of 50 Hz, using interlaced scanning. This means that 25 full frames or 50 fields are built up every second. This relatively low frame rate, derived from the inertia of the human eye and bandwidth optimization, has a motion blur and shows an annoying flicker effect that increases with larger screens and insufficient distance of the viewer. This is referred to as large-screen flicker. To avoid this, the frame rate of televisions and projectors is increased to 100 Hz.
There are several technical approaches to 100 Hz technology. The simplest approach simply doubles the refresh rate by displaying each frame twice in succession. More modern methods increase their repetition rate by calculating additional pictures and inserting them between two TV pictures. This is motion-adaptive image processing, since the flicker effect is particularly pronounced in dynamic displays. This makes the TV picture smoother and sharper, especially in moving presentations.
A further improvement is achieved by the 200 Hz technology, in which not only one intermediate image is calculated, but three at once, which are then included between two TV images.