Abstract: Systems, methods, and apparatus for frequency domain diffuse correlation spectroscopy are provided. In some embodiments, the system comprises: an intensity modulated coherent light source; a photon counting detector; at least one hardware processor that is programmed to: cause the light source to emit light at a plurality of different intensity modulation frequencies toward a tissue sample; detect, for each of the plurality of different modulation frequencies, photon counts over a predetermined period of time; determine, for each of the plurality of modulation frequencies, a normalized intensity auto-correlation function; estimate a plurality of properties of the tissue sample using the plurality of intensity auto-correlation functions; and output at least one of the plurality of properties.

Abstract: A SyntheticMulti-Exposure Speckle Imaging (syMESI) methodology necessarily utilizing an optical interferometer apparatus as part of the speckle imaging system to overcome the optical detector noise that conventionally limits the reliable and accurate determination of a speckle contrast characteristic at low exposure times. The use of such methodology enabled a quantitative determination of absolute value(s) of changes of motion at the target object (such as blood flow changes in tissue) at low photon budget of less than 40 counts of average detection intensity and/or quantitative imaging of the blood flow at the object in interoperative setting with a low-cost camera sensor.

Abstract: A partitioned aperture wavefront imaging system includes an imaging system comprising a partitioned aperture lens array positioned at the aperture plane or Fourier plane between the entrance plane and camera plane of an imaging system. The partitioned aperture lens array can include 2 or more off-axis lenses symmetrically distributed about an optical axis, and adapted to produce simultaneously at the camera plane at least two images of an object, or intermediate image of an object, presented at the entrance plane. Preferably, the partitioned aperture lens array includes from 3 to 5 off-axis lenses and produces 3 to 5 images at the camera plane from which phase and amplitude information about the light field can be determined. The partitioned aperture wavefront imaging system provides enough information about the light field presented at the entrance plane to enable reconstruction of the light field at other planes relative to the entrance plane.

Abstract: A partitioned aperture wavefront imaging system includes an imaging system comprising a partitioned aperture lens array positioned at the aperture plane or Fourier plane between the entrance plane and camera plane of an imaging system. The partitioned aperture lens array can include 2 or more off-axis lenses symmetrically distributed about an optical axis, and adapted to produce simultaneously at the camera plane at least two images of an object, or intermediate image of an object, presented at the entrance plane. Preferably, the partitioned aperture lens array includes from 3 to 5 off-axis lenses and produces 3 to 5 images at the camera plane from which phase and amplitude information about the light field can be determined. The partitioned aperture wavefront imaging system provides enough information about the light field presented at the entrance plane to enable reconstruction of the light field at other planes relative to the entrance plane.