Optical computing optical coherence tomography with conjugate suppression by dispersion.

For all imaging techniques, such as optical coherence tomography (OCT), fast imaging speed is always of high demand. Optical computing OCT (OC2T) has achieved ultrahigh speed for real time 3D imaging without post data processing, but its spatial resolution is lowered down due to an imperfect Fourier transformation in the optical computing process. In this Letter, we illustrate the theory of OC2T and prove that the dispersion imbalance between reference arm and sample arm may be introduced to improve the resolution. Furthermore, this novel OC2T technique can also enable a conjugate restrained OCT imaging without any data processing, achieving ∼2 times higher resolution than typical OC2T. At an imaging speed of 5M-A-scans per second, the dispersion imbalance OC2T has strong ability of restraining the conjugate signal with a conjugate signal rejection ratio of 2.6.