US Patent 7920728 Apparatus and method for fingerprint recognition

An apparatus and method for fingerprint recognition comprises a light source, an optical component, an imaging device and a processor. The light source directs a monochromatic light through the optical component and then forms a plurality of interference fringes on a fingerprint desired to be recognized; the imaging device receives an optical image signal of the interference fringes reflected from the fingerprint and transfers it to an electrical image signal; the processor creates a contour image of the fingerprint according to the electrical image signal for post-recognition.