DEVICE FOR INPUTTING FINGERPRINT USING DOUBLE PRISMS STRUCTURE

摘要

PURPOSE: A device for inputting a fingerprint by using a double prisms structure is provided to obtain a correct fingerprint image with the reduced distortion by reducing a refraction angle of the light reflected on the fingerprint on a seat prism of the double prisms. CONSTITUTION: A seat prism(33) having a fingerprint contact surface(32) refracts an incident angle light in the first angle. A rectangular prism(34) integrated with a lower portion of the seat prism refracts a reflected angle refracted from the seat prism in the second angle. An illuminator(36) attached to one incidence surface(35) of the rectangular prism irradiates the light to the seat prism and the rectangular prism. A mirror(38) refracts the reflected light refracted through the shift prism and the rectangular prism in a specific angle. A CCD(Charge Coupled Device) camera(39) picks up the reflected light refracted through the mirror and outputs an electrical signal corresponding to the fingerprint image.