Embedded Printing of Integrated Quantum Dot Waveguide Deformation Sensors

Authored by

Tobias Biermann, Lennart Mesecke, Simon Teves, Gerrit Eckert, Ole Hill, Ivo Ziesche, Alexander Wolf, Roland Lachmayer

Abstract

We present an optical deformation sensor additively manufactured via an embedded printing process that enables the direct integration of colloidal quantum dots into multimode silicone (PDMS) waveguides. The sensor consists of two parallel waveguide strands, one of which is locally functionalized with CdSe/CdS quantum dots serving as fluorescent emitters. When narrow-band UV light at 405 nm is coupled into the non-functionalized strand, structural deformation alters the conditions of total internal reflection, thereby changing the optical interaction between both strands. This leads to a deformation-dependent variation in the fluorescence shift-affected intensity ratio, which serves as a self-referenced signal for angle determination. Using ratiometric evaluation, angular deflections of up to 9.5° are detected with a resolution below 1° ((Formula presented.) confidence), representing the performance of an initial functional prototype. The embedded printing process allows the voxel-wise adjustment of the material composition within a viscoplastic support medium and thus the spatially resolved integration of quantum dot-functionalized silicone. Attenuation losses of (Formula presented.) at 625 nm confirm the optical suitability of the printed waveguides. This approach combines optical sensing and structural flexibility within a single manufacturing step and establishes a pathway toward fully integratable deformation-sensing elements for soft robotic and wearable systems.

Details

Organisation(s): Institute of Motion Engineering and Mechanism Design
PhoenixD: Photonics, Optics, and Engineering - Innovation Across Disciplines
Institute of Physical Chemistry and Electrochemistry
External Organisation(s): Laser Zentrum Hannover e.V. (LZH)
Deutsches Elektronen-Synchrotron (DESY)
Deutsches Zentrum für Astrophysik
Type: Article
Journal: Sensors
Volume: 26
ISSN: 1424-3210
Publication date: 11.02.2026
Publication status: Published
Peer reviewed: Yes
ASJC Scopus subject areas: Analytical Chemistry, Information Systems, Atomic and Molecular Physics, and Optics, Biochemistry, Instrumentation, Electrical and Electronic Engineering
Electronic version(s): https://doi.org/10.3390/s26041160 (Access: Open )