Laser Optics Enable View Inside a Fly’s Eye

New laser optics technology that supports high-resolution 3-D microscopy is providing a view into the interior of flies, mice and even medical tissue samples.

The technology and the optics in the ultramicroscope device were developed by Saideh Saghafi of the Technical University of Vienna. She turned a laser beam into an extremely thin two-dimensional laser surface, penetrating each layer and capturing a 3-D image of the inside of a fly’s head.

Dr. Saghafi Saideh of the Technical University of Vienna has developed laser optics technology that supports high-resolution 3-D microscopy. The technique can be used to provide a view inside flies, mice and even medical tissue samples. Images courtesy of TU Vienna.

Biological tissues are opaque because the light is scattered at the interfaces between different materials. But for the laser beams in this technology to work, the tissue must be made transparent. The sample is treated first, and any water it contains is replaced with a fluid with different optical properties. This enables laser beams to penetrate deep into the sample.

Optical tricks are used to convert a conventional round laser beam into an optical beam, which is transformed into a layer of light about 1.5 µm thick. Excited by the laser light, an extremely thin layer of the sample begins to fluoresce, enabling the light to be picked up with a camera. Laser light is shone through the sample layer by layer, with an image being taken each time, to create a detailed 3-D image.

Saghafi’s team used the technology to create detailed images of tiny fruit flies and the complex neuronal network in mouse brains.

Interior view of the fly’s head in 3-D.

Without the ability to have the laser penetrate the sample, scientists would have to cut the sample into thin layers and image each segment individually — a more time-consuming and less accurate process than could be achieve with the ultramicroscope, Saghafi said.

Saghafi received $5000 in optical products from Edmund Optics for this work. See: Biomedical Researchers Win Edmund Optics Grants

For more information, visit: www.tuwien.ac.at/en