German Partnership Brings OCT, Laser Transfer Printing to Hearing Aid Manufacturing

Seven businesses and a nonprofit research institute have partnered to improve the functionality and comfort of hearing aids through light-based imaging and manufacturing technologies.

The 3D-PolySPRINT project started in June and is coordinated by Sennheiser electronic GmbH & Co. KG.

Parnters include Kind Hörgeräte GmbH & Co. KG, OptoMedical Technologies GmbH, Materialise GmbH, Dreve ProDiMed GmbH, microTec Gesellschaft für Mikrotechnologie mbH, LPKF Laser & Electronics AG and Lazer Zentrum Hannover eV (LZH). Sennheiser and Kind will be the end users.

Participants at the 3D-PolySPRINT project kickoff meeting in July. Courtesy of Sennheiser.

The collaboration will develop noncontact imaging and combined multimaterial 3D printing processes to manufacture otoplastics optimally adapted to the auditory canal.

Today, hearing aids and individualized in-ear headsets are created by taking a mold of the ear, which is digitized and used to manufacture the otoplastic.

The 3D-PolySPRINT project will explore ways to use optical coherence tomography (OCT) to make a digital image of the auditory canal without having to create a mold. LZH's Image-Guided Laser Surgery group is developing software to convert raw image data into a construction file.

Otoplastics will be created using two additive manufacturing processes: spray coating and laser transfer printing (LTP). LZH's Laser Micromachining Group is developing the necessary process and examining new materials for suitability.

Combining these technologies could speed up the manufacturing process and provide customers with hearing aids that are more comfortable and durable, and that provide better sound quality, according to LZH.

The project is funded by the German Federal Ministry of Education and Research.