Transport of coherent light through randomizing multimode fibers can be thoroughly controlled through the use of holography. Since multimode fibers make for the narrowest channels for image transmission, constructing ultra-narrow endoscopes based on this principle has been tempting since the 1960s. Due to the availability of computer-controlled holographic modulators of light, the last decade has seen great progress in this domain, allowing for high-quality images to be taken deep inside living  tissues.

While most of the achievements have been accomplished with single-frequency sources, some of the most exciting possibilities require broadband, picosecond or even femtosecond pulses, bringing about the need to deal with material and modal dispersion. The EPFL group of Moser and Psaltis has been pioneering this direction since 2015, introducing, among other achievements, a laser-scanning multiphoton micro-endoscope utilizing ~120 fs pulses.

The newest contribution from the group by Kakkava et al. represents yet another technological breakthrough, which combines the multiphoton endoscopy with targeted photoablation of cells, thus manifesting a new means of interaction with living tissues. This may facilitate, for example, deep tissue observations and photolysis of metastatic cells migrating from a tumor body.

---

---

 Add Comment

You must log in to add comments.