Electron Microscopy Sciences G22 Walton & Beckett Graticule, 25 mm

Electron Microscopy Sciences The walton and beckett graticule is for counting fibrous dust (asbestos or glass fibers) and particularly where the majority of fibers to be counted are shorter than 5 microns. The circle is divided into four by two diametrical lines scaled in units of 5 and 3 microns respectively. 3 And 5 microns are the critical measurements of fiber lengths and diameters used in fiber counting. Walton and beckett include shapes with an aspect ratio of 3:1 or 5:1 for comparing to fibers. Important note: the circle on these walton & beckett graticules must represent 100 microns at the stage and each one must be manufactured to the individual instrument. - EMS