A Coupled Triplft Configuration of the Oxford Microprobe

Ream optics calculations have been carried out on three probe forminq quadrupole configurations. The Oxford coupled triplet confiquration (CDC) is shown to have relatively high demagnification in both focussing planes, although at the expense of high chromatic and spherical aberration coefficients. A 2000 lines/inch copper electron microscope mesh has been scanned by a 4 MeV proton beam focussed to a spot using the CDC configuration. Deconvolution of the beam profile from proton induced X-ray profiles of the mesh has yielded dimensions of around 1¿m in both planes.