US Patent 10907951 Single-chip optical coherence tomography device

A high-performance single-chip, integrated-optics-based OCT system is disclosed, where the length of the reference arm is digitally variable. The reference arm includes a plurality of switch stages comprising a 2×2 tunable wavelength-independent waveguide switch that can direct an input light signal onto either of two different-length output waveguides. In some embodiments, the directional couplers are thermo-optic based. Some embodiments include a solid-state scanning system for scanning a sample signal along a line of object points on the sample under test.