Spectral domain optical coherence tomography system

Abstract

An optical coherence tomography device is disclosed for improved imaging. Reduced levels of speckle in the images generated by the device are obtained by forming a B-scan from a plurality of A-scans, wherein each resolution cell of the B-scan is generated through compounding of a subset of the A-scans and wherein at least some of the subset of A-scans are separated by at least half the diameter of a speckle cell both tangent to and orthogonal to the B-scan at that cell.

1 . (canceled) 
     
     
         2 . An optical coherence tomography (OCT) system for imaging a sample, the OCT system including a light source generating a light beam, a sample arm, a reference arm and a detection arm, said OCT system comprising:
 optics for scanning the light beam to a plurality of positions in an X/Y plane on the sample;   a detector coupled to the detection arm for generating output signals in response to light collected from the sample arm and the reference arm;   a rapid-scan optical delay (RSOD) device for adjusting the pathlength difference between the sample and reference arm; and   a controller for adjusting the pathlength difference at different positions in the X/Y plane during the scanning the light beam.   
     
     
         3 . The OCT system as recited in  claim 2 , wherein the pathlength difference at each X/Y position is selected based on a predetermined delay profile. 
     
     
         4 . The OCT system as recited in  claim 3 , wherein the sample is a human retina. 
     
     
         5 . The OCT system as recited in  claim 4 , wherein the predetermined delay profile is determined using OCT data from an initial scan of the retina to determine a fit to a surface of the retina. 
     
     
         6 . The OCT systems as recited in  claim 2 , wherein the pathlength difference adjustment is used to flatten the image of a curved surface. 
     
     
         7 . The OCT systems as recited in  claim 2 , wherein the sample is a human retina. 
     
     
         8 . The OCT system as recited in  claim 2 , wherein the amount of the pathlength difference adjustments are determined on-the-fly between the collection of output signals by the detector at two different X/Y positions. 
     
     
         9 . The OCT system as recited in  claim 2 , wherein the OCT system is a spectral domain OCT system. 
     
     
         10 . The OCT system as recited in  claim 2 , wherein the light source is a super luminescent diode. 
     
     
         11 . The OCT system as recited in  claim 2 , wherein the RSOD device provides a change in group-delay with relatively small phase delay. 
     
     
         12 . The OCT system as recited in  claim 2 , wherein the reference arm is transmissive.