New Microscope is Handy, Quick ... and Flat

A very thin and fast microscope promises to change the way skin cancer is detected. Developed at Fraunhofer Institute for Applied Optics and Precision Engineering (IOF), it provides a high-resolution image of skin areas of any size — and does so quickly enough that one can hold it without blurring the resulting picture.

The microscope has a resolution of 5 μm. For comparable results, a conventional microscope would either be restricted to a tiny field or forced to scan the surface slowly across the skin’s surface point by point before combining the images to create a complete picture. The new microscope makes a single image over a broad area.

In a single pass, the ultrathin microscope can deliver high-resolution images of objects the size of a matchbox. (Image: Fraunhofer IOF)

“Essentially, we can examine a field as large as we want,” said IOF group manager Frank Wippermann. “At 5 μm, the resolution is similar to that of a scanner.” There is also another benefit to the new system: With an optical length of just 5.3 millimeters, the microscope is extremely flat.

But how did researchers accomplish this feat? “Our ultrathin microscope consists of not just one but a multitude of tiny imaging channels, with lots of tiny lenses arrayed alongside one another. Each channel records a tiny segment of the object at the same size for a 1:1 image,” Wippermann said. Each slice is roughly 300 × 300 µm and fits seamlessly alongside the neighboring slice; a computer program then assembles these to generate the overall picture. The difference between this technology and a scanner microscope: All of the image slices are recorded simultaneously.

The researchers will display their first prototype of the microscope at the Laser World of Photonics trade fair in Munich through May 26. It will be at least another one to two years before the device can go into series production, according to the researchers. The spectrum of applications is diverse: With this technology, even documents can be examined for authenticity.

For more information, visit: www.fraunhofer.de