| abstract |
Optical methods and systems for in vivo, non-invasive examination of biological tissue include at least one light source constructed to emit light of a visible or infra-red wavelength for introduction into an examined tissue volume from at least one input port, and at least one detector constructed to detect light of the visible or infra-red wavelength that has migrated in the examined tissue volume from at least one input port to at least one detection port. The optical systems also include an optical array, a radiation controller, and a processor. The optical array includes the input and detection ports located in a selected geometrical pattern providing several average photon migration pathlengths in the examined tissue volume. Each arrangement of least one input port and at least one detection port provides one of the average pathlengths, wherein the average pathlength is characteristic of the tissue between one input port and one detection port. The radiation controller is constructed to sequentially control light emitted from the at least one input port and constructed to control detection of light of the introduced wavelength to define a null plane in the tissue volume for two of the arrangements of the input and detection ports. The processor is operatively connected to the radiation controller and is constructed to examine the biological tissue based on data corresponding to the introduced and detected light for at least two of the average pathlengths and the defined location of the null plane. |