Imaging a three-dimensional structure by confocal focussing an array of light beams

An apparatus for determining surface topology of a teeth portion, comprising:

• a probing member with a sensing end face for placing proximal to the teeth portion;
• an illumination unit comprising at least two light sources emitting light of different wavelength for providing an array of incident light beams each composed of light components from said at least two light sources, for transmitting said beams towards the teeth portion along an optical path through said probing member to generate illuminated spots on said portion;
• a light focusing optics defining a focal plane for each of said light components of each light beam forward said sensing end face at a position changeable by said optics;
• a translation mechanism for displacing said focal plane relative to the teeth portion along said optical path;
• a detector having an array of sensing elements for measuring intensity of each light component of each of a plurality of imaging light beams returning from said spots propagating through an optical path opposite to that of the incident light beams;
• a processor coupled to said detector for determining, for each light component of each light beam, a spot-specific position being the position of the respective focal plane of yielding maximum measured intensity of the imaging light beam, and based on a plurality of determined spot-specific positions, generating data representative of the topology of teeth portion.

An apparatus for determining surface topology of a teeth portion, comprising:

• a probing member with a sensing end face for placing proximal to the teeth portion;
• an illumination unit for providing an array of incident light beams transmitted towards the teeth portion along an optical path through said probing unit to generate illuminated spots on said portion;
• a light focusing optics defining one or more focal planes forward said end face at a position changeable by said optics, each light beam having its focus on one of said focal planes;
• a translation mechanism for displacing said focal planes relative to the teeth portion along an axis defined by the propagation of the incident light beams;
• a detector having an array of sensing elements for measuring intensity of each of a plurality of imaging light beams returning from said spots propagating along an optical path opposite to that of the incident light beams;
• 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 said portion;
• said probing member being in the form of an elongated transparent body having a front face, an end mirror, and top, bottom and side walls extending therebetween, said sensing end face being associated with said bottom wall's outer surface adjacent said end mirror, said bottom wall having a front section extending inwardly from said front face transversely to said top wall and a rear section substantially co-directional with said top wall, said front face being inclined relative to said top wall so as to ensure that light beams incident on the front face perpendicularly thereto impinge said top wall at an angle providing their total internal reflection therefrom and further bouncing, by means of total internal reflection, between the top wall and said rear section of the bottom wall towards said end mirror to be redirected thereby towards said sensing end face.

An apparatus for determining surface topology of a teeth portion, comprising:

• a probing member with a sensing end face for placing proximal to the teeth portion;
• an illumination unit for providing an array of incident light beams transmitted towards the teeth portion along an optical path through said probing unit to generate illuminated spots on said portion;
• a light focusing optics defining one or more focal planes forward said end face at a position changeable by said optics, each light beam having its focus on one of said focal planes;
• a translation mechanism for displacing the focal planes relative to the teeth portion along an axis defined by the propagation of the incident light beams;
• a detector having an array of sensing elements for measuring intensity of each of a plurality of imaging light beams returning from said spots propagating along an optical path opposite to that of the incident light beams;
• 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 said portion;
• said probing member being in the form of an elongated transparent body having a front face, an end mirror, and top, bottom and side walls extending therebetween, said sensing end face being in the form of a transparent plate fixed to said bottom wall's outer surface and spaced therefrom by an air gap.