Computational Optics

Computational dispersion correction and k-space resampling in OCT  

Dispersion compensation

k-space resampling

Beam-divergence, scattering, and aberrations

Figure 2.2.  Illustration for the effect of OCT system’s NA on the expected OCT images. Each row corresponds to a specific numerical aperture of the system from very low NA (≈0), low NA (≈0-0.2), and high NA (> 0.5). The OCT images shown in the right column are not actual images but are cartoon illustrations. The axes are as indicated in the image. 

Figure 2.3. Zernike Polynomials from orders N =0 to 6. Polynomials in a row have the same order N. Commonly observed aberrations such as defocus, astigmatism, and spherical are indicated. 

Wavefront sampling and forward problem

Wavefront sampling

Image formation in OCT

Description in space domain

Description in spatial-frequency domain

Approximations for a practical system

Adding aberrations to the model

Summary of the forward problem

Inverse problem

Solving the scattering problem the traditional way

Solving the inverse scattering problem with resampling

Practical considerations

Algorithm for ISAM and CAO

Results from just wavefront resampling and aberration correction

References