Scan pattern and signal processing for optical coherence tomography

An optical coherence tomography (OCT) system to measure a tissue layer of an eye, comprising:

• an OCT interferometer comprising a light source to generate a measurement beam, a scanner for moving the measurement beam on the tissue layer in a scan pattern, a plurality of optical elements, and a detector;
• and
• a processor operatively coupled to the scanner and configured to execute instructions to cause the scanner to move the measurement beam on the tissue layer in the scan pattern, wherein the scan pattern comprises a plurality of lobes;
• wherein the scanner comprises a mirror configured to pivot about a first pivot axis and a second pivot axis transverse to the first pivot axis to move the measurement beam along the scan pattern;
• wherein the scanner comprises a first resonance frequency for rotation of the mirror about the first pivot axis and a second resonance frequency for rotation of the mirror about the second pivot axis, the first resonance frequency different from the second resonance frequency by at least about 25%.