Apparatus and method for selective data collection and signal to noise ratio enhancement using optical coherence tomography

A method for performing optical imaging on a sample using an optical imaging device comprising an optical radiation source;

• a sample arm terminating in a probe assembly, the probe assembly comprising a first scanning mechanism that controls the transverse or angular position on a sample at which imaging is performed, the sample position being selectively varied by the first scanning mechanism to scan a sample in at least one transverse or angular dimension;
• a reference arm comprising a reference optical reflector;
• a first optical path optically coupling the optical radiation source to the probe assembly and a second optical path optically coupling the optical radiation source to the reflector, the optical source applying optical radiation through the first optical path and the probe assembly to a sample and through the second optical path to the reflector;
• a second scanning mechanism that determines a longitudinal range with respect to a sample from which imaging information is obtained;
• an optical combiner that combines reflections from the sample received through the first optical path and reflections from the reflector received through the second optical path, the resulting combined optical output having optical interference fringes;
• a detector that detects the output;
• and a processor that processes the detected output to obtain a selected image of the sample, the method comprising:
• determining a longitudinal range containing a selective portion of a sample from which it is desired that imaging information be obtained;
• and
• controlling the second scanning mechanism to obtain imaging information only from the determined longitudinal range.

A system for performing optical imaging on a sample, comprising:

• an optical radiation source;
• a sample arm terminating in a probe assembly, the probe assembly comprising a first scanning mechanism that controls the transverse or angular position on a sample at which imaging is performed, the sample position being selectively varied by the first scanning mechanism to scan a sample in at least one transverse or angular dimension;
• a first optical path optically coupling the optical radiation source to the probe and a second optical path optically coupling the optical radiation source to a reflector, the optical source applying optical radiation through the first optical path and the probe assembly to a sample and through the second optical path to the reflector;
• a second scanning mechanism that determines a longitudinal range relative to the probe assembly from which imaging information is obtained;
• a controller that controls the second scanning mechanism to obtain imaging information from a longitudinal range from which it is desired that imaging information be obtained;
• a start point adjustment device that determines a point with respect to a sample at which collected imaging information will be utilized;
• an optical combiner that combines reflections from the sample received through the first optical path and reflections from the reflector received through the second optical path, the resulting combined optical output having optical interference fringes;
• a detector that detects the output;
• and
• a processor that processes the detected output to obtain a selected image of the sample.

A system for collecting position data of a sample, comprising:

• an interferometer that receives optical radiation and having a first optical path and a second optical path, whereby a first portion of said optical radiation travels along the first optical path and a second portion of said optical radiation travels along the second optical path;
• an optical path length varying mechanism that varies a length of one of said first and second optical paths;
• a detector optically coupled to said interferometer for outputting position data by detecting said first and second portions of said optical radiation after traveling along said first and second optical paths, respectively;
• a controller coupled to said optical path length varying mechanism for controlling the optical path length varying mechanism;
• and
• a starting point adjustment device coupled to said controller that determines a point with respect to the sample to start collecting the position data.