Patent ID: 6864970

Claim:
An apparatus for detecting irregular or foreign objects in products moving through a scanning zone, said apparatus comprising: a light source, said light source directing a concentrated light beam having a given cross sectional area in a scanning pattern towards a scanning zone wherein said products move through said scanning zone and are impinged upon by said light beam moving in said scanning pattern, said light being directly reflected from generally the impingement point of said light beam on said products and diffusely reflected from an area around said impingement point due to diffusion of said light beam into said products; a first detector disposed to receive reflected light back from said products, said first detector having a first field of view larger than said light beam cross sectional area wherein said first detector is sensitive to substantially all of said direct and diffused reflected light from said products and generates a first signal corresponding thereto; a second detector disposed to receive reflected light back from said products, said second detector having a second field of view generally equal to said cross sectional area of said light beam wherein said second detector is sensitive to substantially only said direct reflected light from said products and generates a second signal corresponding thereto; and control circuitry in operable communication with said first and second detectors to receive said first and second signals and generate control signals based on either of said signals individually or a difference of said signals.