German engineers have created a camera no bigger than a grain of salt that could change the future of health imaging—and clandestine surveillance.
Using 3-D printing, researchers from the University of Stuttgart built a three-lens camera, and fit it onto the end of an optical fibre the width of two hairs.
Such technology could be used as minimally-intrusive endoscopes for exploring inside the human body, the engineers reported in the journal Nature Photonics.
Ref: Two-photon direct laser writing of ultracompact multi-lens objectives. Nature Photonics (27 June 2016) | DOI: 10.1038/nphoton.2016.121
Current lens systems are restricted in size, shape and dimensions by limitations of manufacturing. Multi-lens elements with non-spherical shapes are required for high optical performance and to correct for aberrations when imaging at wide angles and large fields. Here we present a novel concept in optics that overcomes all of the aforementioned difficulties and opens the new field of 3D printed micro- and nano-optics with complex lens designs. We demonstrate the complete process chain, from optical design, manufacturing by femtosecond two-photon direct laser writing and testing to the application of multi-lens objectives with sizes around 100 µm, and validate their high performance and functionality by quantitative measurements of the modulation transfer function and aberrations. The unprecedented flexibility of our method paves the way towards printed optical miniature instruments such as endoscopes, fibre-imaging systems for cell biology, new illumination systems, miniature optical fibre traps, integrated quantum emitters and detectors, and miniature drones and robots with autonomous vision.