Patent ID: 6160543
Filing Date: 2000-12-12
Classification: G09G

Abstract:
A transmission device for computer video signals having a converter and a receiver, said converter receiving and processing computer video signals, and transmitting said computer video signals by only three pairs of transmission line to said receiver at a remote terminal, wherein said converter comprising:a synchronous signal polarity separating circuit having inputs to be linked with a horizontal synchronous signal (Hsync) and a vertical synchronous signal (Vsync) outputted from a computer video signal interface, and having outputs to be linked with a polarity mode generating circuit and a differential output circuit stated as below, such that said horizontal synchronous signal (Hsync) and said vertical synchronous signal (Vsync) being processed to get an inverted polarity level of the horizontal synchronous signal (CTRLH), an inverted polarity level of the vertical synchronous signal (CTRLV), a negative pulse for vertical synchronous signal (V), a negative pulse for horizontal synchronous signal (H);a polarity mode generating circuit for receiving said CTRLH, CTRLV, and V signals, and outputting a state pulse (STATE) to be inputed into a differential output circuit stated as below;a differential output circuit having inputs to be linked with said V and H signals, said STATE signal, as well as a red (R), a green (G), and a blue (B) video signals of said computer video signals, and having outputs linked with said three pairs of transmission line to be transmitted to said receiver in said remote terminal;said receiver comprising:a differential receiving circuit having inputs to be linked with said transmission lines, and having outputs to be outputted to a color signal recovering circuit and a polarity mode recovering circuit stated as below;a color signal recovering circuit having inputs to be linked with said differential receiving circuit, and outputting a red video signal (R), a green video signal (G), and a blue video signal (B);a polarity mode recovering circuit having inputs to be linked with said differential receiving circuit, and having outputs to be linked with a synchronous signal recovering circuit state as below, for removing said red, green, and blue video signals to output said negative pulse for vertical synchronous signal (V), said state pulse (STATE),and said negative pulse for horizontal synchronous signal (H).a synchronous signal recovering circuit having inputs to be linked with said outputs from said polarity mode recovering circuit, and outputting said horizontal synchronous signal (Hsync) and said vertical synchronous signal (Vsync).