We propose optical spectral encoding of an object's spatial frequencies as a means of transmitting, through a low-numerical-aperture optical system, spatial information with an instantaneous spatial frequency bandwidth wider than the optical system's diffraction-limited bandwidth. We validate this new superresolution approach experimentally and demonstrate one of its possible practical implementations—wide-field spectrally encoded imaging that is sensitive to nanometre-scale local variations in the microstructure of centimetre-scale samples.
Alexandrov, S., & Sampson, D. (2008). Spatial information transmission beyong a system's diffraction limit using optical spectral encoding of the spatial frequency. Journal of Optics. A, Pure and Applied Optics, 10(2), 1-5. https://doi.org/10.1088/1464-4258/10/2/025304