Patent ID: 7915564

Claim:
A gemstone marking system, comprising: (a) a laser, said laser generating a laser beam having a focal plane having a positional relationship with respect to a marking surface of a gemstone; (b) a mechanism adapted to reposition the gemstone relative to said focal plane of said laser beam; (c) a sensor adapted to optically sense a relative position between said marking surface of the gemstone and said focal plane of said laser beam, comprising a side camera that is both substantially horizontal with respect to the center of the gemstone when in the desired position and substantially perpendicular to the laser beam passing through a focusing lens, for measuring an illumination of said marking surface, said illumination being dependent on a relative position between said marking surface of the gemstone and said focal plane of said laser beam, and producing an output in dependence upon said illumination; and (d) a signal processing unit operationally coupled to said camera for receiving said output and producing data corresponding to the relative position of said marking surface of the gemstone and said focal plane of said laser beam; wherein said mechanism comprises means, operationally coupled to said signal processing unit, for translating the gemstone relative to said focal plane of said laser beam to automatically control the position of the marking surface of the gemstone relative to the focal plane in response to said data received from said signal processing unit.