Donate to Science & Enterprise

S&E on Mastodon

S&E on LinkedIn

S&E on Flipboard

Please share Science & Enterprise

University Engineers Develop Single Lens for 3D Microscope

3D lens (Kevin Fitzsimons, Ohio State University)

3D lens (Kevin Fitzsimons, Ohio State University)

Engineers at Ohio State University in Columbus have invented a lens that enables microscopic objects to be seen from nine different angles at once to create a 3D image. Engineering professor Allen Yi, and postdoctoral researcher Lei Li discuss the lens in the November 2010 issue of the Journal of the Optical Society of America A (paid subscription required).

Yi calls the lens (pictured left) a proof of concept for manufacturers of microelectronics and medical devices, who now use more complex devices that the lens developed at Ohio State. While other microscopes can display 3D images, they use multiple lenses or cameras that move around an object. The new lens is the first single, stationary lens to create microscopic 3D images by itself.

The prototype lens is about the size of a fingernail, and looks at first glance like a gem cut for a ring, with a flat top surrounded by eight facets. Unlike gemstones, however, this lens is not symmetric. The sizes and angles of the facets vary in minute ways. This is called a freeform lens that exposes different shapes from various angles.

While freeform optics have been in use for more than a decade, postdoc Lei Li wrote a computer program to design a freeform lens for imaging microscopic objects. The engineers then used that program to drive a commercially available milling tool with a diamond blade to cut the shape from polymethyl methacrylate, a common transparent plastic sometimes called acrylic glass. The machine shaved bits of plastic from the lens in increments of 10 nanometers, or 10 billionths of a meter.

Each facet on the lens captures an image of the objects from a different angle, which can be assembled via computer into a 3D image. The engineers tested the lens by recording 3D images of the tip of a ballpoint pen — about 1 millimeter in diameter — and a mini drill bit with a diameter of 0.2 millimeters.

Yi would like to develop the technology for manufacturers. He points out that the medical testing industry is a candidate for using a 3D microscope with this lens. Medical testing labs are interested in shrinking devices that analyze fluid samples. Cutting tiny reservoirs and channels in plastic requires a clear view, and the depths must be carved with precision.

Read more:

*     *     *

1 comment to University Engineers Develop Single Lens for 3D Microscope