Peach pit detection apparatus and method

摘要

A peach sorting system (110) conveys peaches (114) on a conveyor belt (112) past an inspection zone (126) that is lighted by an illumination source (90) radiating a number of emission peaks over visible and infrared portions of the spectrum. The illumination source generates the radiation from an Indium Iodide lamp (92) that is reflected off a parabolic reflector (94) and through a "soda straw" collimator (100) to illuminated the peaches. A detector system (118) employs line scanning visible and infrared cameras (142, 140) to sense visible and IR wavelength reflectance value differences existing between peach meat (124) and peach pit or pit fragments (126). Because there is a reversal in the reflectance values between the visible and infrared wavelengths, a data subtraction technique (150) is employed to enhance the detection contrast ratio. The data subtraction technique also cancels "glint" caused by specular reflections of the illumination source off the peaches and into the cameras.