Dynamic distortion in resonant galvanometric optical scanners.

Alfredo Dubra // Publications // Nov 01 2020

PubMed ID: 34368405

Author(s): Akondi V, Kowalski B, Burns SA, Dubra A. Dynamic distortion in resonant galvanometric optical scanners. Optica. 2020 Nov;7(11):1506-1513. doi: 10.1364/optica.405187. Epub 2020 Oct 27. PMID 34368405

Journal: Optica, Volume 7, Issue 11, Nov 2020

High-speed optical systems are revolutionizing biomedical imaging in microscopy, DNA sequencing, and flow cytometry, as well as numerous other applications, including data storage, display technologies, printing, and autonomous vehicles. These systems often achieve the necessary imaging or sensing speed through the use of resonant galvanometric optical scanners. Here, we show that the optical performance of these devices suffers due to the dynamic mirror distortion that arises from the variation in torque with angular displacement. In one of two scanners tested, these distortions result in a variation of signal-to-noise (Strehl) ratio by an order of magnitude across the field of view, degrading transverse resolution by more than a factor of 2. This mirror distortion could be mitigated through the use of stiffer materials, such as beryllium or silicon carbide, at the expense of surface roughness, as these cannot be polished to the same degree of smoothness as common optical glasses. The repeatability of the dynamic distortion indicates that computational and optical corrective methods are also possible.