Voice coil based robust and miniature optical delay for multiple reference optical coherence tomography

Multiple reference optical coherence tomography (MR-OCT) is a recently developed time-domain interferometeric imaging platform, which promises to fit into robust, cost-effective designs that are virtually solid state. An optical delay is created by the reference mirror which is mounted on a piezo-electric transducer (PZT) and the key element of MR-OCT technology is the presence of a partial mirror in front of the reference mirror. However, the limited axial displacement range at higher scanning-frequencies are a limitation of a PZT-based optical delay. Moreover, PZT-based actuators require a relatively high operational voltage and are expensive. In this paper we present a voice coil actuator as an alternative to a PZT-based optical delay. Voice coil actuators are light in weight, inexpensive and offer other advantages such as zero hysteresis, low operational voltage and a long life. We demonstrate a voice coil actuator as a feasible alternative to PZT-based actuators for the purpose of creating an optical delay, which can provide fast and precise axial displacements at high scanning rates.