Method and apparatus for imaging three-dimensional structure

Abstract

An apparatus for determining surface topology of a portion of a three-dimensional structure is provided, that includes a probe, a light emitter, focusing optics, a detector, and a processor.

What is claimed is: 
     
         1 . An apparatus for determining surface topology of a portion of a three-dimensional structure, the apparatus comprising:
 a probe;   a light emitter configured to emit a plurality of emitted light beams;   focusing optics configured to focus the plurality of emitted light beams to a focal plane external to the probe;   a detector configured to measure a characteristic of a plurality of returned light beams, the returned light beams being a portion of the plurality of emitted light beams reflected from a portion of the three-dimensional structure; and   a processor coupled to the detector and configured to determine a surface topology of the portion of the three-dimensional structure based at least in part on the measured characteristic of the plurality of returned light beams.   
     
     
         2 . The apparatus of  claim 1 , wherein the detector comprises a plurality of sensor elements each configured to measure the characteristic of a corresponding returned light beam in the plurality of returned light beams. 
     
     
         3 . The apparatus of  claim 1 , wherein the focusing optics comprises a translation mechanism configured to change a position of the focal plane over a range of focal plane positions relative to the probe. 
     
     
         4 . The apparatus of  claim 3 , wherein the detector is configured to measure the characteristic of the plurality of returned light beams over the range of focal plane positions. 
     
     
         5 . The apparatus of  claim 4 , wherein the processor is configured to determine the surface topology based on the characteristic of the plurality of returned light beams measured by the detector over the range of focal plane positions. 
     
     
         6 . The apparatus of  claim 3 , wherein the translation mechanism is configured to change the position of the focal plane along a direction of propagation of the plurality of emitted light beams. 
     
     
         7 . The apparatus of  claim 1 , wherein the probe comprises a probe face, and wherein the focal plane is positioned beyond of the probe face. 
     
     
         8 . A method for imaging a portion of a three-dimensional structure, the method comprising:
 providing an apparatus comprising:
 a probe; 
 a light emitter configured to emit a plurality of incident light beams; 
 focusing optics configured to focus the plurality of emitted light beams to a focal plane external to the probe; 
 a detector configured to measure a characteristic of a plurality of returned light beams, the returned light beams being a portion of the plurality of emitted light beams reflected from a portion of the three-dimensional structure; and 
   a processor coupled to the detector and configured to determine a surface topology of the portion of the three-dimensional structure based at least in part on the measured characteristic of the plurality of returned light beams.   
     
     
         9 . The method of  claim 8 , wherein the detector comprises a plurality of sensor elements each configured to measure a characteristic of a corresponding returned light beam in the plurality of returned light beams. 
     
     
         10 . The method of  claim 8 , wherein the optical system comprises a translation mechanism configured to change a position of the focal plane over a range of focal plane positions relative to the probe. 
     
     
         11 . The method of  claim 10 , wherein the detector is configured to measure the characteristic of the plurality of returned light beams over the range of focal plane positions. 
     
     
         12 . The method of  claim 11 , wherein the processor is configured to determine the surface topology based on the characteristic of the plurality of returned light beams measured by the detector over the range of focal plane positions. 
     
     
         13 . The method of  claim 10 , wherein the translation mechanism is configured to change the position of the focal plane along a direction of propagation of the plurality of incident light beams. 
     
     
         14 . The method of  claim 8 , wherein the probe comprises a probe face, and wherein the focal plane is positioned forward of the probe face. 
     
     
         15 . A method for imaging a portion of a three-dimensional structure, the method comprising:
 providing a probe;   emitting a plurality of light beams;   focusing the plurality of light beams to a focal plane external to the probe;   measuring a characteristic of a plurality of returned light beams, the returned light beams being a portion of the plurality of emitted light beams reflected from a portion of the three-dimensional structure; and   determining a surface topology of the portion of three-dimensional structure based at least in part on the measured characteristic of the plurality of returned light beams.   
     
     
         16 . The method of  claim 15 , further comprising changing a position of the focal plane over a range of focal plane positions relative to the probe. 
     
     
         17 . The method of  claim 16 , wherein the position of the focal plane of the plurality of incident light beams is changed along a direction of propagation of the plurality of light beams. 
     
     
         18 . The method of  claim 16 , wherein the characteristic of the plurality of returned light beams is measured over the range of focal plane positions. 
     
     
         19 . The method of  claim 17 , wherein the surface topology is determined based on the characteristic of the plurality of returned light beams measured over the range of focal plane positions. 
     
     
         20 . The method of  claim 15 , wherein the probe comprises a probe face, and wherein the focal plane is positioned forward of the probe face.