Stylus/digitizer combination with elongate reflectors and linear CCD

Claim 1

A digitizer/stylus combination comprises a digitizer board and a stylus, thereby the stylus operating on the digitizer board and generating a corresponding image on a screen of a personal computer, characterized in said stylus having an LED (light emitting diode) disposed thereon and emitting infrared light which includes a series of light spots when said stylus is actuated and moved by a user, and said digitizer board comprising: a rectangular casing with a first protruding portion and a second protruding portion formed on two adjacent sides thereof; a first bar-like window and a second bar-like window being formed under said first protruding portion and said second protruding portion respectively for constituting two light channels for receiving an X beam and Y beam emitted from a light spot which is provided by said stylus, thereby obtaining a real position of said light spot, a series of said light spots constituting a light curve which also passes through said bar-like windows; an interior plate being disposed under the rectangular casing for providing a writing area thereon; a first reflector means being disposed in one side of said interior plate, in a position corresponding to said first protruding portion, and a second reflector means being disposed in adjacent to said first reflector means in a position corresponding to said second protruding portion, each of said reflector means being composed of two bar-like reflectors, first upper reflector, first lower reflector, second upper reflector, and second lower reflector, wherein said first upper reflector engaged to s id first lower reflector with a right angle therebetween, said second upper reflector engaged to said second lower reflector with a right angle therebetween; a first focus lens being disposed opposite to said first reflector means on said interior plate for focusing the light from said first reflector means, and a second focus lens being disposed opposite to said second reflector means on said interior plate for focusing the light from the second reflector means; and a first linear CCD image receiver being disposed opposite to said first reflector means and disposed under one side of said interior plate right behind said first focusing lens for receiving the light therefrom and converting the light to first electrical signal which represents an X component of a specific light spot, and a second linear CCD image receiver being disposed opposite to said second reflector means, disposed under one side of said interior plate behind said second focusing lens for receiving the light therefrom and converting the light to a second electrical signal which represents a Y component of said specific light spot, said first electrical signal and said second electrical signal being coupled to an image processing circuit which utilizes a ROM mapping technique to process said electric signal to a corresponding X, Y coordinates which together represent said specific light spot and shows a corresponding cursor point in a screen of a personal computer.