Optical coherence tomography based 1D to 6D eye-in-hand calibration

Optical coherence tomography (OCT) is an interferometric imaging modality with spatial resolution in the micrometer range. The OCT signal can be used to detect small structures to measure deformation or to characterize tissue. Moreover, OCT can be realized through a single optical fiber, i.e., it can be easily integrated with instruments. However, to use OCT for intra-operative guidance its spatial alignment needs to be established. Hence, we consider eye-in-hand calibration between the 1D OCT imaging and a 6D robotic position system. We present a method to perform pivot calibration for OCT and based on this introduce pivot
⁺
d, a new 1D to 6D eye-in-hand calibration. We provide detailed results on the convergence and accuracy of our method and use translational and rotational ground truth to show that our methods allow for submillimeter positioning accuracy of an OCT beam with a robot. For pivot calibration we observe a mean translational error of 0.5161 ± 0.4549 mm while pivot
⁺
d shows 0.3772 ± 0.2383 mm. Additionally, pivot
⁺
d improves rotation detection by about 8° when compared to pivot calibration.