Bacteriorhodopsin film has a special property of complementary suppression modulated transmission of yellow and blue beams. Resolving the transmission rate equ ations of the yellow and blue beams, the analytical formulae are obtained and gr aphic results are shown. We put forward a multilateralsystem computational mod el of digital optical matrix addition and subtraction operations without carry a nd abdication respectively. The novel model and frame of basic optical computati on are constructed, and the optimized project of digital optical matrix addition and subtraction operations are designed.