Balanced detection spectral domain optical coherence tomography with a multiline single camera for signal-to-noise ratio enhancement.

In this study, the use and advantages of balanced detection (BD) in spectral domain optical coherence tomography (SD-OCT) are demonstrated. A-scans are calculated as a combination of two phase-opposed interferometric spectra acquired simultaneously by using a multiline single camera spectrometer. Not only does this system suppress artifacts due to autocorrelation, but also the signal of interest is increased by a factor of 2 as experimentally verified. Our BD-based SD-OCT gives a signal-to-noise ratio improvement of 8-14 dB for the peak within 1 mm compared to standard SD-OCT using a single detection scheme. This method is validated by experimental measurement of a glass plate.