Patent ID: 8730536

Claim:
A scanning apparatus for scanning an image of at least one paper sheet, said scanning apparatus comprising: a sheet input tray for placing the at least one paper sheet thereon; a scanning module comprising an optical sensing element for reading said image of said at least one paper sheet at a scanning position; a transfer channel; a sheet pick-up module located near said sheet input tray for feeding said at least one paper sheet on said sheet input tray into said transfer channel; and a sheet size detecting mechanism comprising: a first sheet guide part disposed on said sheet input tray; a second sheet guide part disposed on said sheet input tray, wherein said second sheet guide part is movable relative to said sheet input tray, so that said first sheet guide part and said second sheet guide part are contactable with two parallel edges of said at least one paper sheet, respectively, wherein at least one light-emitting unit is disposed on at least one of said first sheet guide part and said second sheet guide part for projecting a light beam onto said optical sensing element, wherein according to said light beam, said optical sensing element generates a sensing signal; and a controlling unit electrically connected with said optical sensing element for receiving said sensing signal and acquiring a distance between said two parallel edges of said at least one paper sheet according to said sensing signal.