Patent ID: 6879403

Claim:
A system for measuring the spatial dimensions of a three-dimensional object positioned on an object plane, comprising: a light source for emitting wavelengths of light, said light source being positioned so as to direct said wavelengths of light at said object without any intermediate structures therebetween and so as to direct said wavelengths of light over an area of said object; a lens positioned to receive reflections of said wavelengths of light from said object, wherein said lens has a high degree of chromatic aberration; an optical axis normal to said object plane and passing through a focal point of said lens; a sensor a plurality of photodetectors, each of said plurality of photodetectors having electrical outputs, said sensor being positioned to receive said reflections of said wavelengths of light after said reflection pass through said lens, said sensor in optical alignment with said object along said optical axis; a diffraction grating disposed between said lens and said sensor for directing each of said wavelengths of light to a different one of said plurality of photodetectors, said diffraction grating in optical alignment with said sensor along said optical axis; a processor for receiving said electrical outputs from each of said plurality of photodetectors, said processor determining a distance of said object from said lens and thereby a height of said object.