Spectral domain optical imaging with wavelength comb illumination

An optical imaging method comprising the steps of:

• illuminating a contiguous volume of an object with an extended illumination field comprising a plurality of linearly displaced combs of wavelengths selected from across a bandwidth of a multi-wavelength light source;
• splitting light in the extended illumination field into a reference beam and a sample beam, and combining the reference beam with light from the sample beam reflected or scattered from the illuminated volume of the object;
• and
• simultaneously capturing, with a measurement system comprising a spatial sampling element and a two-dimensional sensor array, phase and amplitude information over a range of wavelengths in the linearly displaced plurality of combs of wavelengths, of the reflected or scattered light,
• wherein:
• the spatial sampling element comprises a cylindrical lenslet array,
• the reflected or scattered light is sampled in the far field in a first dimension by the cylindrical lenslet array,
• the two-dimensional sensor array comprises pixels, and
• the reflected or scattered light is sampled in the near field in a second dimension by the pixels.

An optical imaging apparatus comprising:

• an illumination system comprising a multi-wavelength light source and a wavelength comb generator for illuminating a contiguous volume of an object with an extended illumination field comprising a plurality of linearly displaced combs of wavelengths selected from across a bandwidth of the light source, the volume to be imaged in three spatial dimensions;
• one or more beam splitters for splitting light in the extended illumination field into a reference beam and a sample beam, and for combining the reference beam with light from the sample beam reflected or scattered from the illuminated volume of the object;
• and
• a measurement system comprising a spatial sampling element and a two-dimensional sensor array for simultaneous capture of phase and amplitude information, over a range of wavelengths in the linearly displaced plurality of combs of wavelengths, of the reflected or scattered light,
• wherein:
• the extended illumination field has a short axis and a long axis,
• the extended illumination field is spatially coherent over the short axis, and
• a spatial coherence distance of the long axis is less than a length of the long axis.

An optical imaging method comprising the steps of:

• illuminating a contiguous volume of an object with an extended illumination field comprising a plurality of linearly displaced combs of wavelengths selected from across a bandwidth of a multi-wavelength light source;
• splitting light in the extended illumination field into a reference beam and a sample beam, and combining the reference beam with light from the sample beam reflected or scattered from the illuminated volume of the object;
• and
• simultaneously capturing, with a measurement system comprising a spatial sampling element and a two-dimensional sensor array, phase and amplitude information over a range of wavelengths in the linearly displaced plurality of combs of wavelengths, of the reflected or scattered light,
• wherein:
• the extended illumination field has a short axis and a long axis,
• the extended illumination field is spatially coherent over the short axis, and
• a spatial coherence distance of the long axis is less than a length of the long axis.