Optical probe using multimode optical waveguide and proximal processing

A method of optical probing with an optical fiber transmitting multiple spatial modes from a proximal end to a distal end of the optical fiber, the method comprising:

• a) generating an optical beam with an optical source;
• b) coupling the optical beam to a proximal end of the optical fiber transmitting multiple spatial modes so that the optical beam propagates from the proximal end to a distal end of the optical fiber thereby producing a spatial transformation of the optical beam;
• c) imparting a compensating spatial profile on the optical beam that at least partially compensates for the spatial transformation produced by the optical fiber;
• d) generating a calibration light with a distal source having an output positioned proximate to the distal end of the optical fiber;
• e) detecting at least a portion of the calibration light with an optical detector;
• and
• f) processing the detected calibration light to generate a calibration signal that determines the imparted compensating spatial profile on the optical beam that at least partially compensates for the spatial transformation produced by the optical fiber.

A method of optical probing with an optical fiber propagating multiple spatial modes from a distal end to a proximal end of the optical fiber, the method comprising:

• a) collecting an optical beam comprising a spatial profile from a sample proximate to the distal end of the optical fiber propagating multiple spatial modes;
• b) propagating the collected optical beam from the distal end to the proximal end of the optical fiber propagating multiple spatial modes, the optical fiber imparting a spatial transformation of the collected optical beam as it propagates from the distal end to the proximal end;
• c) detecting at least a portion of the propagated optical beam at an output of the proximal end of the optical fiber and generating an electrical signal in response to the detection;
• and
• d) processing the electrical signal to generate a mathematical transformation of the electrical signal that at least partially compensates for the spatial transformation imparted by the optical fiber.

An optical system comprising:

• a) an optical source;
• b) a wavefront control device having an input that is optically coupled to an output of the optical source;
• and
• c) an optical fiber having an input that is optically coupled to an output of the wavefront control device, the optical fiber propagating multiple spatial modes from a proximal end to a distal end, wherein the optical source is configured to illuminate a sample positioned near the distal end of the optical fiber, the optical fiber comprising at least one proximally control distal source positioned near the distal end of the optical fiber, wherein the distal source is configured to provide information about a transformation performed by the optical fiber to determine one or more optical properties of the sample.

A method of determining information about optical properties of a sample, the method comprising:

• a) generating an optical beam with an optical source;
• b) propagating the optical beam from a proximal end to a distal end of an optical fiber that propagates multiple spatial modes;
• c) illuminating a sample positioned after the distal end of the optical fiber with the propagated optical beam;
• d) generating calibration light using a distal optical source;
• e) propagating at least a portion of the calibration light through at least a portion of the optical fiber;
• and
• f) determining information about an optical property of the sample using a portion of the propagated calibration light.

An optical fiber measurement system comprising:

• a) an optical source that generates an optical beam at an output;
• b) an optical control device optically connected to the output of the optical source;
• c) an optical fiber comprising an optical waveguide that propagates multiple spatial modes, a proximal end of the optical fiber being optically connected to an output of the optical control device;
• d) a distal optical source that generates a calibration light, an output of the distal optical source optically connected near the distal end of the optical fiber such that at least a portion of the calibration light propagates through at least a portion of the optical fiber;
• and
• e) a sample positioned to receive illumination from the distal end of the optical fiber, wherein the optical measurement system determines an optical property of the sample using a portion of the calibration light.