Patent ID: 7796277

Claim:
A hand held apparatus for determining surface topology of a portion of a three-dimensional dental structure, comprising: (A) a probing member having a front face and a sensing face; (B) an illumination unit for providing an array of incident light beams transmitted towards the structure each along a respective optical path through said probing member via said front face, the probing member being configured for directing said incident light beams towards the dental structure via said sensing face to generate respective illuminated spots on said portion; (C) a light focusing optics defining one or more focal planes forward said sensing face at a position changeable by said optics, each light beam having its focus on one of said one or more focal plane; (D) a translation mechanism for displacing said focal plane relative to the structure along an axis defined by the propagation of the incident light beams; (E) a detector having an array of sensing elements for measuring intensity of each of a plurality of light beams returning from said spots propagating through an optical path opposite to that of the incident light beams; and (F) a processor coupled to said detector for determining for each light beam a spot-specific position, being the position of the respective focal plane of said one or more focal planes yielding maximum measured intensity of the returned light beam, and based on the determined spot-specific positions, generating data representative of the topology of portion.