Scanning White Light Interferometry
The short coherence length of the white light can be used to find the surface profile of various objects: silicon wafers, micromechanical components, ceramics, biological samples, thin films etc. The optical system can be scaled to meet the needs of the particular application by adjusting the magnification, the light source wavelength etc. The resolution is in nanometer range (1-2 nm) and with phase-shifting (and smaller measurement range) the resolution in the range of 0.1 nm is achieved.
Contact:
Dr. Ivan Kassamakov
ivan.kassamakov[at]helsinki.fi
Photonic nanojet super-resolution imaging
Combining SWLI with photonic nanojets, a microsphere/object assisted optical focusing, we are able to push resolution limits of white light below the conventional diffraction limitation. This allows to boost the performance of our SWLI device to achieve resolutions of 50x50x1 nm (xyz). All this without sample preparation and maintaining working distances similar to high magnification conventional optics.
Contact:
Dr. Ivan Kassamakov
ivan.kassamakov[at]helsinki.fi
Schlieren imaging
Seeing sound & pressure with Schlieren imaging. We have developed Schlieren instrument in our laboratory for measuring pressure wave propagation from shock waves to acoustic fields.