Patent ID: 6494586
Filing Date: 2002-12-17
Classification: H04N

Abstract:
A back-light module for projecting a light source to an image scanning device provided with an optical scanning module, comprising:a casing; a bottom plate mounted on the casing, the bottom plate having a central opening with symmetric opposite sides; a light projecting window having two symmetric opposite edges corresponding to the opposite sides of the central opening of the bottom plate; a light guide plate mounted in the casing and having two symmetric opposite edges corresponding to that of the light projecting window, the light guide plate having two outward wing portions respectively formed on a middle section of the opposite edges of the light guide plate; and a pair of tubular lamps respectively arranged adjacent the two opposite edges of the light guide plate, each of the tubular lamps having a shape corresponding to the symmetric opposite edges of the light guide plate; wherein the light source generated by the tubular lamps is guided by the light guide plate and then projected to the optical scanning module of the scanner via the light projecting window.