Optical probe design with extended depth-of-focus for optical coherence microscopy and optical coherence tomography

In this report, Optical probe system for modality, optical coherence tomography (OCT) and optical coherence microscope (OCM), is presented. In order to control the back focal length from 2.2 mm to 27 mm, optical probe is designed using two liquid lenses and several lenses. The narrow depth of focus (DOF) in microscope is extended by phase filter such as cubic filter. The filter is modified so that DOF is extended only In the OCM mode. The section for the extended DOF of probe is controlled by iris. Therefore in OCT mode, the phase filter does not affect on the DOF of lens. In OCM mode, the Gaussian light and modified light will affect the DOF. The probe dimension is less than 4 mm diameter and less than 60 mm long. The scan range of system is 0.88 mm wide, 1 mm deep in the OCT and 510 mu m wide, 1 mm deep in the OCM mode. The lens curvature and iris aperture are operated by digital microelectrofluidic lens and iris.