An optical fibre with 3D printed doublet Fresnel lenses is inserted into a water droplet to image the beam profile by an inverse microscope. A white light laser passed through the objective is used to align the fibre in respect to the objective and causes the blue colour of the lenses in the refracted image on the surface of the droplet. The image is taken by a 100mm f/2.8 micro lens on a DSLR (Canon 60D). The image is cropped, and gone under noise reduction and contrast enhancement.
This photo involves equal contribution of two colleagues: measurement setup and fabrication by Dr Asa Asadollahbaik, photography by Mr Moritz Floess. The fabrication and design also includes the collaboration of Mr Simon Thiele and Ms Ksenia Weber. The image is taken at Optics Lab in 4th Physics Institute (Head of the Institute: Professor Harald Giessen), University of Stuttgart, Stuttgart.
—Asa Asadollahbaik, 4th Physics Institute, University of Stuttgart