Latest publication : Direct imaging of photonic nanojets

29 Mai 2008 , Rédigé par JW Publié dans #Recent research work

Published recently in Optics Express, it’s freely available at :
http://www.opticsinfobase.org/abstract.cfm?URI=oe-16-10-6930

We investigate the focusing of light by single latex microspheres illuminated by a collimated beam. Measurements are performed with a fast scanning confocal microscope in detection mode, where the detection pinhole defines a diffraction-limited observation volume that is scanned in three dimensions over the microsphere vicinity. From the collected stack of images, we reconstruct the full 3 dimensional photonic nanojet beam created by the microsphere.

Remarkably, we measure spot sizes as small as 270 nm FWHM for a wavelength of 520 nm. The beam keeps a subwavelength FWHM over a propagation distance of more than 3 micrometers, displaying all the specificities of a photonic nanojet. 

Click on the video below to visualize the photonic nanojet :