Systems and methods for endoscopic angle-resolved low coherence interferometry

Abstract

Fourier domain a/LCI (faLCI) system and method which enables in vivo data acquisition at rapid rates using a single scan. Angle-resolved and depth resolved spectra information is obtained with one scan. The reference arm can remain fixed with respect to the sample due to only one scan required. A reference signal and a reflected sample signal are cross-correlated and dispersed at a multitude of reflected angles off of the sample, thereby representing reflections from a multitude of points on the sample at the same time in parallel. Information about all depths of the sample at each of the multitude of different points on the sample can be obtained with one scan on the order of approximately 40 milliseconds. From the spatial, cross-correlated reference signal, structural (size) information can also be obtained using techniques that allow size information of scatterers to be obtained from angle-resolved data.

1 . An apparatus comprising:
 a first arrangement configured to receive at least one first electro-magnetic radiation, and forward at least one second electro-magnetic radiation within a solid angle to a sample, wherein the at least one second electro-magnetic radiation is associated with the at least one first electro-magnetic radiation, wherein the first arrangement is configured to receive a plurality of third electro-magnetic radiations from the sample which is associated with the at least one second electro-magnetic radiation, and wherein at least one portion of the third electro-magnetic radiations is provided outside a periphery of the solid angle; and   a second arrangement configured to simultaneously detect signals which are (i) provided along optical axes associated therewith that are different from one another, and (ii) associated with each of the third electro-magnetic radiations, wherein the signals are associated with information for the at least one sample at a plurality of depths thereof, and wherein the second arrangement is configured to determine the depths using the at least one portion of the third electro-magnetic radiations.   
     
     
         2 . The apparatus according to  claim 1 , further comprising a third arrangement configured to detect an interference between the at least one portion of the third electro-magnetic radiation and at least one fourth electro-magnetic radiation associated with the at least one first electro-magnetic radiation, and to obtain information associated with the sample as a function of the depths within the sample based on the interference. 
     
     
         3 . The apparatus according to  claim 1 , further comprising a third arrangement configured to provide data associated with at least one of spectroscopic properties, angular back-scattering properties or elastic properties of at least one portion of the sample as a function of the signals. 
     
     
         4 . The apparatus according to  claim 1 , further comprising a third arrangement configured to provide data associated with scattering characteristics of at least one portion of the sample as a function of a combination of the signals. 
     
     
         5 . The apparatus according to  claim 1 , wherein the second arrangement is configured to determine the depths using a single one of the third electro-magnetic radiations. 
     
     
         6 . The apparatus according to  claim 1 , wherein the second arrangement is further configured to combine the signals. 
     
     
         7 . A method for detecting signals, comprising:
 receiving at least one first electro-magnetic radiation;   forwarding at least one second electro-magnetic radiation within a solid angle to a sample,
 wherein the at least one second electro-magnetic radiation is associated with the at least one first electro-magnetic radiation; 
   receiving a plurality of third electro-magnetic radiations from the sample which is associated with
 the at least one second electro-magnetic radiation, wherein at least one portion of the third electro-magnetic radiations is provided outside a periphery of the solid angle; 
   simultaneously detecting the signals which are (i) provided along optical axes associated
 therewith that are different from one another, and (ii) associated with each of the third 
 electro-magnetic radiations, wherein the signals are associated with information for the at least one sample at a plurality of depths thereof, and 
   using a computer arrangement, determining the depths using the at least one portion of the third electro-magnetic radiations.   
     
     
         8 . The method according to  claim 7 , further comprising, after the simultaneous detection, combining the signals. 
     
     
         9 . An apparatus comprising:
 a first arrangement configured to receive at least one first electro-magnetic radiation, and forward
 at least one second electro-magnetic radiation within a solid angle to a sample, wherein the at least one second electro-magnetic radiation is associated with the at least one first electro-magnetic radiation, wherein the first arrangement is configured to simultaneously receive at least two of a plurality of third electro-magnetic radiations from the sample which is associated with the at least one second electro-magnetic radiation, and wherein at least one portion of the third electro-magnetic radiations is provided outside a periphery of the solid angle; and 
   a second arrangement configured to simultaneously detect an interference between the at least
 two of the third radiations which are provided along optical axes associated therewith that are different from one another and at least one fourth radiation associated with the at least one first radiation, and configured to obtain information associated with the sample as a function of at least one depth within the sample based on the interference. 
   
     
     
         10 . The apparatus according to  claim 9 , wherein the second arrangement is configured to determine the at least one depth based on the interference. 
     
     
         11 . The apparatus according to  claim 9 , wherein the one second arrangement is configured to simultaneously detect signals associated with each of the third electro-magnetic radiations. 
     
     
         12 . The apparatus according to  claim 11 , further comprising a third arrangement configured to provide data associated with at least one of spectroscopic properties, angular back-scattering properties or elastic properties of at least one portion of the sample as a function of the signals. 
     
     
         13 . The apparatus according to  claim 11 , further comprising a third arrangement configured to provide data associated with scattering characteristics of at least one portion of the sample as a function of a combination of the signals. 
     
     
         14 . The apparatus according to  claim 10 , wherein the second arrangement is configured to determine the depths using a single one of the third electro-magnetic radiations. 
     
     
         15 . A method for detecting signals, comprising:
 receiving at least one first electro-magnetic radiation;   forwarding at least one second electro-magnetic radiation within a solid angle to a sample,
 wherein the at least one second electro-magnetic radiation is associated with the at least one first electro-magnetic radiation; 
   simultaneously receiving at least two of a plurality of third electro-magnetic radiations from the
 sample which is associated with the at least one second electro-magnetic radiation, wherein at least one portion of the third electro-magnetic radiations is provided outside a periphery of the solid angle; 
   simultaneously detecting an interference between the at least two of the third radiations and at
 least one fourth radiation associated with the at least one first radiation wherein the third radiations are provided along optical axes associated therewith that are different from one another; and 
   using a computer arrangement, obtaining information associated with the sample as a function of at least one depth within the sample based on the interference.   
     
     
         16 . The method according to  claim 15 , further comprising simultaneously detecting signals associated with each of the third electro-magnetic radiations which are provided along optical axes associated therewith that are different from one another.