An integrated-optics-based optical coherence tomography system having a sample arm and a reference arm, the OCT system comprising: a photonic lightwave circuit 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 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 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 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 to the delay controller for compensating a dispersion mismatch between the reference arm and sample arm based on the dispersion signal.