Abstract

The absence of confocal gating in full-field optical coherence tomography (OCT) worsens its dynamic range and thereby the sensitivity and signal to background noise ratio because of the inability to reject the out-of-focus and other incoherent light. Here, we present a simple and affordable confocal line scanning implementation that significantly reduces the incoherent light. We realize a fully digital line scanning that contains no moving parts, by exploiting a digital mirror device (DMD) in combination with a CMOS camera running in the rolling shutter mode. An improvement of the signal to noise ratio due to the confocal line-scanning by at least an order of magnitude was demonstrated on a sample composed of the USAF target mounted behind a scattering layer. We also imaged a sample of onion epidermis with an incoherent reflector.

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