Three-dimensional microfabrication through a multimode optical fiber

TL;DR

This paper introduces a novel 3D microfabrication technique using two-photon polymerization through a tiny multimode optical fiber, enabling high-resolution structures in hard-to-access areas.

Contribution

It demonstrates the first microfabrication process through a multimode optical fiber, expanding the possibilities of endoscopic additive manufacturing.

Findings

Achieved 500 nm resolution in 3D structures.

Successfully focused femtosecond pulses through a 560 μm fiber.

First demonstration of microfabrication via a multimode optical fiber.

Abstract

Additive manufacturing, also known as 3D printing, is an advanced manufacturing technique that allows the fabrication of arbitrary macroscopic and microscopic objects. All 3D printing systems require large optical elements or nozzles in proximity to the built structure. This prevents their use in applications in which there is no direct access to the area where the objects have to be printed. Here, we demonstrate three-dimensional microfabrication based on two-photon polymerization (TPP) with sub diffraction-limited resolution through an ultra-thin, 50 mm long printing nozzle of 560 micrometers in diameter. Using wavefront shaping, femtosecond infrared pulses are focused and scanned through a multimode optical fiber (MMF) inside a photoresist that polymerizes via two-photon absorption. We show the construction of arbitrary 3D structures of 500 nm resolution on the other side of the fiber. To our knowledge, this is the first demonstration of microfabrication through a multimode optical fiber. Our work represents a new area which we refer to as endofabrication.