Ultrathin endoscopes: nonlinear lensless imaging at the tip of a multimode fiber
(Conference Presentation)

Siddharth Sivankutty; Esben R. Andresen; Géraud Bouwmans; Serge Monneret; Hervé Rigneault

doi:10.1117/12.2209266

27 April 2016 Ultrathin endoscopes: nonlinear lensless imaging at the tip of a multimode fiber (Conference Presentation)

Siddharth Sivankutty, Esben R. Andresen, Géraud Bouwmans, Serge Monneret, Hervé Rigneault

Author Affiliations +

Proceedings Volume 9717, Adaptive Optics and Wavefront Control for Biological Systems II; 97171D (2016) https://doi.org/10.1117/12.2209266
Event: SPIE BiOS, 2016, San Francisco, California, United States

Abstract

Recent advances in wavefront shaping techniques have enabled so-called lensless endoscopes using fiber probes. Unlocking the full potential of such endoscopes call for the capability of optically sectioned and/or label free imaging. Or in other words, imaging through fibers must retain the functionality of a nonlinear microscope. This is a key challenge due to the temporal broadening of ultrashort pulses in fibers owing to modal dispersion. Here, we detail the first ever demonstration of two photon fluorescence imaging at the distal tip of a conventional graded index (GRIN) multimode fiber. GRIN fibers possess a high mode density, excellent throughput and limited temporal broadening. These features, in addition to its ready availability, make them attractive candidates for ultrathin endoscopes. In our approach, we apply the transmission matrix formalism and treat these fibers akin to highly scattering media. This lets us retrieve combinations of input modes that would generate intense focal spots throughout the field of view. Furthermore, we identify a regime where the modal dispersion in the fiber is minimal and two-photon excitation with femtosecond light pulses is possible. This allows us to perform two-photon imaging with ultrashort pulses in an epi-detection configuration analogous to conventional nonlinear microscopes. Finally, these concepts are validated by acquiring optically sectioned two photon fluorescence images of 3D samples with cellular resolution. We believe this first report of an ultrathin rigid endoscope of only 125 µm thickness would further accelerate the development of novel tools for demanding applications in biological imaging and opto-genetics.

Conference Presentation

Citation Download Citation

Siddharth Sivankutty, Esben R. Andresen, Géraud Bouwmans, Serge Monneret, and Hervé Rigneault "Ultrathin endoscopes: nonlinear lensless imaging at the tip of a multimode fiber (Conference Presentation)", Proc. SPIE 9717, Adaptive Optics and Wavefront Control for Biological Systems II, 97171D (27 April 2016); https://doi.org/10.1117/12.2209266

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members: $17.00

Non-members: $21.00 ADD TO CART

PROCEEDINGS
PRESENTATION

WATCH
PRESENTATION SAVE TO MY LIBRARY

GET CITATION

KEYWORDS

Endoscopes

Two photon imaging

Multimode fibers

Dispersion

GRIN lenses

Luminescence

Microscopes

Show All Keywords

Keywords/Phrases

Search In:

Publication Years