An easy-to-build long working distance microscope

In order to obtain sharp images of objects inside an optical cryostat, we h ave designed a microscope with all optical elements outside the cryostat. T his microscope resolves 2 mu m at a working distance of 20 cm. It is easy t o build and not expensive, as only standard components are used except for one single lens. (C) 2000 Elsevier Science B.V. All rights reserved.