Abstract: A high-resolution single-chip spectrometer is disclosed. Embodiments of the present invention are analogous to Fourier-transform spectrometers; however, embodiments of the present invention have no moving parts. An illustrative embodiment is a spectrometer having a nested plurality of Mach-Zehnder interferometers (MZIs), where all MZIs share at least one surface-waveguide section in each of its sample and reference arms. The light signals in the sample and reference arms are tapped at a series of discrete locations along their length via electro-optically-controlled directional couplers, which are separated by uniform-length waveguide portions in each arm, but where the uniform lengths are different in the sample and reference arms providing a different path-length difference for the arms of each MZI. The tapped light from the sample and reference arms is recombined at a low-loss beam combiner to generate a distribution of optical power as a function of time-delay difference in the arms.

Abstract: 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.

Abstract: A high-resolution single-chip spectrometer is disclosed. Embodiments of the present invention are analogous to Fourier-transform spectrometers; however, embodiments of the present invention have no moving parts. An illustrative embodiment is a spectrometer having a nested plurality of Mach-Zehnder interferometers (MZIs), where all MZIs share at least one surface-waveguide section in each of its sample and reference arms. The light signals in the sample and reference arms are tapped at a series of discrete locations along their length via electro-optically-controlled directional couplers, which are separated by uniform-length waveguide portions in each arm, but where the uniform lengths are different in the sample and reference arms providing a different path-length difference for the arms of each MZI. The tapped light from the sample and reference arms is recombined at a low-loss beam combiner to generate a distribution of optical power as a function of time-delay difference in the arms.

Abstract: 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.