1. A method for acquiring a person's signature, comprising: concurrently acquiring signature information with respect to light movements projected in a signature motion sequence with an image-processing device; and wherein the step of concurrently acquiring signature information with respect to the projected light movements comprises (i) capturing substantially all of the projected light movements in an overexposed signature-information image at selected time intervals, and (ii) compiling the overexposed signature-information images into a signature image that shows the position of the light movements at substantially every interval of time in the signature motion sequence.