Correction of non-uniform angular velocity and sub-pixel jitter in optical scanning

Optical scanners are widely used in high-resolution scientific, medical, and industrial devices. The accuracy and precision of these instruments are often limited by angular speed fluctuations due to rotational inertia and by poor synchronization between scanning and light detection, respectively. Here we demonstrate that both problems can be mitigated by recording scanner orientation in synchrony with light detection, followed by data resampling. This approach is illustrated with synthetic and experimental data from a point-scanning microscope with a resonant scanner and a non-resonant scanner. Fitting of the resonant scanner orientation data to a cosine model was used to correct image warping and sampling jitter, as well as to precisely interleave image lines collected during the clockwise and counterclockwise resonant scanner portions of the rotation cycle. Vertical scanner orientation data interpolation was used to correct image distortion due to angular speed fluctuations following abrupt control signal changes. (c) 2021 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement

Automated summary

The accuracy and precision of optical scanners can be improved by recording scanner orientation in synchrony with light detection, followed by data resampling. This approach effectively corrects image warping, sampling jitter, and image distortion caused by angular speed fluctuations. It is applicable to both resonant and non-resonant scanners and has been demonstrated using synthetic and experimental data.