The Walton and Beckett graticule is used for counting fibrous dust (e.g. asbestos or glass fibers) and is particularly useful where the majority of fibers to be counted are shorter than 5 micron.
The circle on the Walton & Beckett graticule represent 100 microns at the stage.
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 used in fiber counting.
Click the 'Walton + Beckett' to insert. This can be done on live or still images.
The graticule will use the system calibration, an re-size accordingly.
Example of a 'Walton + Beckett'.