Method and apparatus for contact image scanning

A contact image scanner comprises a light source, pixel sensors generating a signal, a lens focusing reflected light onto the pixel sensors, a color matrix filter filtering the reflected light, and a signal processing circuit generating a digital image. The method provides pixel sensors for generating a signal in response to incident light, projects light from a light source onto a document in a sequential fashion, reflects the light onto the pixel sensors, filters the reflected light with a color matrix filter, and processes the signal to generate the digital image. With the method and apparatus, each scan line of the document is illuminated with white light only once. The pixel sensors corresponding to red, green, and blue colors of each pixel of the scan line read the pixel of the scan line substantially at the same time in a substantially overlapping manner in a scan line direction without overlapping in an orthogonal direction.