An integrated-optics-based optical coherence tomography (OCT) system having a sample arm and a reference arm , the OCT system comprising: a photonic lightwave circuit (PLC) that is monolithically integrated on a substrate , wherein the PLC includes: (i) a coupler for distributing an input light signal into a sample signal on the sample arm and a reference signal on the reference arm ; (ii) a beam combiner for combining the reference signal and a reflected signal from a sample to generate an interference signal , the reflected signal being based on the sample signal and the sample ; and (iii) the reference arm , wherein the reference arm is operative for conveying the reference signal from the coupler to the beam combiner , and wherein the reference arm includes a delay controller that is operative for digitally controlling the length of the reference arm within a range from a minimum length to a maximum length; a first photodetector configured to provide an output signal based on the interference signal ; characterised in that the system further comprises: a second photodetector configured to provide a dispersion signal that is based on a first signal received from the delay controller , wherein the first signal includes at least a portion of the reference signal ; and a processor that is operative for providing a control signal (CV) to the delay controller for compensating a dispersion mismatch between the reference arm and sample arm based on the dispersion signal . a photonic lightwave circuit (PLC) that is monolithically integrated on a substrate , wherein the PLC includes: (i) a coupler for distributing an input light signal into a sample signal on the sample arm and a reference signal on the reference arm ; (ii) a beam combiner for combining the reference signal and a reflected signal from a sample to generate an interference signal , the reflected signal being based on the sample signal and the sample ; and (iii) the reference arm , wherein the reference arm is operative for conveying the reference signal from the coupler to the beam combiner , and wherein the reference arm includes a delay controller that is operative for digitally controlling the length of the reference arm within a range from a minimum length to a maximum length; (i) a coupler for distributing an input light signal into a sample signal on the sample arm and a reference signal on the reference arm ; (ii) a beam combiner for combining the reference signal and a reflected signal from a sample to generate an interference signal , the reflected signal being based on the sample signal and the sample ; and (iii) the reference arm , wherein the reference arm is operative for conveying the reference signal from the coupler to the beam combiner , and wherein the reference arm includes a delay controller that is operative for digitally controlling the length of the reference arm within a range from a minimum length to a maximum length; a first photodetector configured to provide an output signal based on the interference signal ; characterised in that the system further comprises: a second photodetector configured to provide a dispersion signal that is based on a first signal received from the delay controller , wherein the first signal includes at least a portion of the reference signal ; and a processor that is operative for providing a control signal (CV) to the delay controller for compensating a dispersion mismatch between the reference arm and sample arm based on the dispersion signal . a second photodetector configured to provide a dispersion signal that is based on a first signal received from the delay controller , wherein the first signal includes at least a portion of the reference signal ; and a processor that is operative for providing a control signal (CV) to the delay controller for compensating a dispersion mismatch between the reference arm and sample arm based on the dispersion signal . <EOS>