a method and apparatus for providing information associated with at least one portion of a sample can be provided . for example , at least one wavelength of electro - magnetic radiation provided on a sample can be encoded to determine at least one transverse location of the portion . a relative phase between at least one first electro - magnetic radiation electro - magnetic radiation being returned from a sample and at least one second electro - magnetic radiation returned from a reference can be obtained to determine at least one relative depth location of the portion . further , the information of the portion can be provided based on the transverse location and the relative depth location . for example , the information can be depth information and / or three - dimensional information associated with the portion of the sample .