Patent ID: 7124950

Claim:
A system capable of producing a raster-type laser scanning pattern for scanning 2-D bar code symbols along x and y axis scanning directions, said system comprising: a housing; a light source disposed in said housing, for producing a light beam having cross-sectional characteristics suitable for scanning a 2-D bar code symbol bar code symbol along x and y axis scanning directions; a first light beam scanning mechanism, disposed in said housing and responsive to a first control signal, for scanning said light beam along said x axis scanning direction using a first scanning element, wherein said first light beam scanning mechanism includes a first electromagnetically driven coil for driving said first scanning element; a second light beam scanning mechanism, disposed in said housing and responsive to a second control signal, for scanning said light beam along said y axis scanning direction orthogonal to said x axis scanning direction using a second scanning element, wherein said second light beam scanning mechanism includes a second electromagnetically driven coil for driving said second scanning element; light collecting means disposed in said housing, for collecting light reflected off a bar code symbol scanned by said scanning pattern; light detecting means disposed in said housing, for detecting said collected light and producing scan data indicative of the intensity of said detected light; and electronic scanning mechanism control circuitry, disposed in said housing, for electrically controlling the operation of said first and second scanning elements so as to produce a raster-type scanning pattern for scanning said 2-D bar code symbol along x and y axis scanning directions; wherein said electronic scanning mechanism control circuitry includes (i) a push-pull type drive circuit for producing an x-axis drive voltage signal having periodic characteristics, for driving said first scanning element along said x axis direction, and (ii) an electronically-controlled potentiometer for producing a y-axis drive voltage signal periodically incrementing and decrementing in small quantized voltage level steps, in response to a control signal generated independently from said x-axis drive voltage signal, for driving said second scanning element along said y axis direction.