Giessen

The scientists have used an ultrashort laser pulses in combination with optical photoresist to create optical lenses, which are just larger than a human hair.

By deploying 3D printing method, the optical free form surfaces can be created with sub-micrometer accuracy.

The precision of the 3D laser enables to construct common spherical lenses, as well as ideal surfaces such as paraboloids or aspheres of higher order.

Specifically, the optical lens systems with two or more lenses can be made with the help of 3D printing method.

The university’s professor Harald Giessen’s student Timo Gissibl printed microobjectives with a diameter and height of 125┬Ám even on optical fibers.

He also printed optical free form surfaces and miniature objectives directly onto CMOS image chips, helping to create an extremely compact sensor.

In addition, illumination of ring-shaped areas, triangles, or elongated rectangles can be made with miniature free-form optics.

Giessen said: "The time from the idea, the optics design, a CAD model, to the finished, 3D printed micro-objectives is going to be less than a day.

"We are going to open potentials just like computer-aided design and computer-integrated manufacturing did in mechanical engineering a few years ago".


Image: Complex triplet lens by femtosecond 3D printing on a single mode optical fiber. Photo: courtesy of University of Stuttgart.