Two-oscillator scan stability
Horace M Joseph · Transactions of the American Institute of Electrical Engineers Part I Communication and Electronics · 1960
The usual regularly repeated raster scan, such as used for television picture presentation, is the result of two perpendicular deflection waves which produce a complex Lissajous figure in the form of a set of closely interwoven lines. The number of lines that appear in this raster during each repetition is an important factor in determining the amount of video information that can be presented.