The present invention provides methods, systems and equipment for acquiring and extracting information using a biological feature. The method for acquiring information using a biological feature—includes: acquiring first data by a terminal； controlling, by the terminal, a light source to generate an intensity-variable light signal according to the first data, and projecting the intensity-variable light signal on an iris； acquiring, by the terminal, first iris information at least comprising first iris contraction information, in which the first iris contraction information is generated by the iris according to the intensity-variable light signal and comprises a first iris contraction activity； acquiring, by the terminal, second iris information at least comprising second iris contraction information； and extracting, by the terminal, second data from the second iris contraction information according to a preset rule.
