The present invention discloses methods and devices for transmitting/obtaining information by visible light signals. The method for transmitting information by visible light signals of two or more wavelengths from light sources comprises: modulating, on the basis of the information to be transmitted, two or more driving signals of the light sources to obtain two or more modulated driving signals for driving the light sources to emit the visible light signals of two or more wavelengths having their levels changed between peak levels and bottom levels with different frequencies and/or different phases and/or different amplitudes; and emitting the visible light signals of two or more wavelengths having their levels changed between peak levels and bottom levels with different frequencies and/or different phases and/or different amplitudes on the basis of the two or more modulated driving signals, so as to transmit information corresponding to a pattern of color stripes shown in an image obtained from the visible light signals.