Long-working-distance microscopic imaging in a turbid medium by use of an ultrafast optical Kerr gate.

Abstract

We demonstrate a long-working-distance microscopic imaging of hidden objects in a turbid medium by use of an ultrafast optical Kerr gate (OKG). The results show that the working distance and the spatial resolution of the long-working-distance microscopic imaging system have been increased simultaneously compared with those of the conventional 4f OKG imaging systems. A compound lens consisting of a long-focus achromatic doublet and a microscope objective is used to increase the long working distance and ensure the sufficient spatial resolution. The microscopic OKG imaging system with a working distance of 245 mm and a maximal spatial resolution of approximately 7 μm has been performed.