UZH researchers develop innovative light microscope

Under the leadership of the neuroscientist Fabian Voigt, UZH researchers have developed an innovative objective for light microscopy. An astronomical telescope built by Bernhard Schmidt back in the 1930s and the eyes of scallops served as reference points around which the invention, which is known as the “Schmidt objective”, is based, further details of which can be found in a press release issued by UZH.  In each case, a combination of spherical mirrors and a single correction lens is used instead of a large number of lenses.

The objective developed by the UZH researchers can be described as a Schmidt telescope that has been shrunk to the size of a microscope and filled with a liquid immersion medium. This boasts a wide range of advantages compared with conventional microscopes. The Schmidt objective can be manufactured much more cost-effectively than a conventional microscope lens for research purposes, with commercial lenses tending to usually be exclusively designed for a specific immersion medium, such as oil or water. In contrast, it is possible to design the objective developed at UZH “in a way that it provides excellent image quality in any homogeneous fluid as well as in air”, Voigt explains. 

This also makes the innovative objective of interest for applications in what are known as clearing techniques. In this context, rather than laboriously cutting tissue samples into the thinnest possible slices, these techniques can make the whole sample transparent. According to UZH, the immersion media used for such procedures are compatible with the Schmidt objective, while conventional microscope lenses are usually unable to cope with them. hs